JPH08278673A - Image forming method and image forming device - Google Patents

Abstract

PURPOSE: To provide a small-sized image forming device capable of forming an image at high speed and also forming an excellent color image even in a high humidity environment. CONSTITUTION: The device is constituted of a 1st image forming unit Pa with a 1st image forming means and a 1st transfer means and for forming a 1st toner image, and a 2nd image forming unit Pb with a 2nd image forming means and a 2nd transfer means and for forming a 2nd toner image. Besides, the device is provided with a fixing means 7 for fixing the 1st toner image and the 2nd toner image which are transferred to a transfer material 6 and a carrying means for carrying the transfer material 6 to the 1st image forming unit Pa, the 2nd image forming unit Pb and the fixing means 7. The length of the transfer material 6 in the carrying direction is made longer than a distance between a 1st transfer part and a 2nd transfer part, a 1st transfer bias is different from a 2nd transfer bias in size, and both the 1st toner and the 2nd toner are provided with shape factor; SF-1 of 100 to 180 and SF-2 of 100 to 140.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method and an image forming apparatus, and in particular, it forms toner images of different colors on a latent image carrier such as a plurality of electrophotographic photoconductors. An image forming method and an image forming method applicable to a color electrophotographic apparatus such as a color printer and a color copying machine, in which the formed toner images are sequentially transferred onto the same transfer material and the toner images transferred onto the transfer material are fixed. Regarding the device.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus is provided with a plurality of image forming units, each image forming unit forms a toner image of a different color, and the toner images are sequentially transferred to the same transfer material, a so-called color image. Although various forming apparatuses have been proposed, a color recording apparatus using a multicolor electrophotographic system is widely used.

The apparatus main body of a color electrophotographic recording apparatus which has been generally used in the past is an apparatus having one image forming section provided in the apparatus main body, for example, as shown in FIG.
The image forming unit in the apparatus main body has one latent image carrier (photosensitive drum) 501, and the outer periphery thereof is a polygon for scanning light emitted from the exposure lamp 521, the drum charger 502, and a light source device (not shown). A mirror 517 is provided. A laser beam emitted from a light source device (not shown) is scanned by rotating a polygon mirror 517, and an image signal is passed through an fθ lens that condenses the scanning light whose light flux is deflected by the reflection mirror on the generatrix of the photosensitive drum 501. To form an electrostatic latent image.

Further, reference numeral 503 is a rotary developing device, and a yellow developing device 503a and a magenta developing device 5 are provided in the rotating body.
03b, cyan developing device 503c, black developing device 503
It is equipped with d. This developing device 503a, 503b, 5
03c and 503d are cyan (hereinafter abbreviated as C),
Magenta (hereinafter abbreviated as M), yellow (hereinafter abbreviated as Y), and black (hereinafter abbreviated as K) color developers are filled in predetermined amounts by a supply device (not shown).

When forming a color image, first, an electrostatic latent image corresponding to each color toner is formed by the scanning light on a photosensitive drum through a color separation filter having a complementary color relationship with light from a document. . Then, a developing device corresponding to each color forms a visible image on the photosensitive drum 501 according to the latent image. Further, the recording material 506 as a transfer material in the recording material cassette 560 is electrostatically carried on the transfer material carrying body 508, and the transfer material carrying body 508 and the photosensitive drum 501 which is a latent image carrying body. The image is transferred by the transfer charger 504 in the visible image transfer portion which is rotated in synchronization and developed by the developing device. This step is sequentially performed a plurality of times, the toners are overlaid on the same recording material while the registration is adjusted, and when this step is completed, the recording material 506 is separated from the recording material carrier 508 by a separating claw or the like, and the conveying belt is conveyed. Is sent to the fixing device 507 by the fixing roller 57.
The recording material 506 is passed between the pressure roller 572 and the pressure roller 572, so that the recording material 506 is heated and pressed, and the final full-color image is obtained by only one fixing. The toner particles remaining on the photosensitive body of the photosensitive drum 501 without being transferred onto the transfer material are removed from the photosensitive body by the cleaning device 505.

The image forming apparatus having one image forming section in the main body of the apparatus as described above has an advantage that the size of the apparatus is compact, but it is possible to perform static operation three or four times on one latent image carrier. There is a drawback in that the printing speed becomes slower because the latent image formation must be performed.

Therefore, recently, for example, Japanese Patent Laid-Open No. 53-74.
No. 037 (corresponding U.S. Pat. No. 4,162,843) discloses that a plurality of photoconductors are stacked for speeding up color image output, and a transfer material is conveyed by a belt-shaped conveying means. There has been proposed an image forming apparatus that sequentially multiple-transfers toner images.

According to this method, a full-color image can be formed on a recording material by a single movement of the transfer material, so that the printing speed is significantly increased, but the apparatus becomes large in size, and the recent apparatus body is compact. It was difficult to deal with this.

In an image forming apparatus in which a plurality of the photoconductors are stacked and a transfer material is conveyed by a belt-shaped conveying means, the toner images are sequentially transferred in a multiple manner, in order to achieve compactness, for example, It is conceivable to reduce the diameter of the photosensitive drums and reduce the distance between the photosensitive drums.

However, when the distance between the photosensitive drums is narrowed by a certain distance or more, the following new problems occur.

That is, when the color toner images of different tones are sequentially transferred onto the transfer material to form a full-color image, the transfer bias output applied to the first transfer portion is applied to the second transfer portion. The transfer bias output is set high, the first toner image is present on the transfer material, and the transfer bias is applied from the back surface of the transfer material at the first transfer portion to apply the transfer bias to the front surface side of the transfer material. To solve the problem that the transfer bias, which substantially acts on the second toner image in the second transfer portion, decreases due to the charge having the opposite polarity to the charge, and the transfer efficiency is reduced. This is conventionally done.

When the transfer bias output applied to the second transfer section is set to be larger than the transfer bias output applied to the first transfer section, for example, in order to make the image forming apparatus main body compact, When the first transfer portion and the second transfer portion are brought close to each other and the distance between the first transfer portion and the second transfer portion is set to be shorter than the length of the transfer material in the transport direction, the first transfer portion is set. Of the second transfer portion before the completion of the transfer of the first toner image at the first transfer portion due to the difference in the transfer bias output applied to the first transfer portion and the second transfer portion. Since the transfer of the first toner image in the first transfer portion is completed before the transfer of the image is started and the transfer of the second toner image is completed, the transfer material is first transferred in a high temperature and high humidity environment.
The problem that the transfer state of the second toner image at the second transfer portion fluctuates before and after passing through the transfer portion is likely to occur.

This is because the paper as the transfer material absorbs moisture under high temperature and high humidity, and the electric resistance of the transfer material decreases, so that the second toner image is transferred at the second transfer portion. When the transfer material does not pass through the first transfer portion, the transfer bias applied to the second transfer portion is transferred to the first transfer portion side where the transfer bias applied through the transfer material having a low electric resistance and the transfer bias output is low. Since the leakage occurs, the transfer bias that substantially acts on the second toner image at the second transfer portion becomes lower than the setting, and when the transfer material next passes through the first transfer portion, Since the leakage of the transfer bias applied to the second transfer portion does not occur along the transfer material, the transfer bias that substantially acts on the second toner image at the second transfer portion approaches the setting, so that the transfer material Applied to the second transfer part before and after passing through the first transfer part of Substantial effect on the second toner image of the transfer bias is believed to be because varied.

This problem tends to occur particularly when the distance between the first transfer portion and the second transfer portion is narrowed, and is particularly remarkable when the distance is 110 mm or less.

Therefore, conventionally, the distance between the respective photosensitive drums is set so that the above-mentioned problems are not substantially caused, so that both the compactness of the image forming apparatus body and the high image quality are satisfied. I couldn't.

[0016]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming method and an image forming apparatus which solve the above problems.

An object of the present invention is to provide an image forming method and an image forming apparatus capable of forming a full-color image having a small size and high-speed printing performance.

It is an object of the present invention to provide an image forming method and an image forming apparatus capable of obtaining high image quality with little or no change in color tone under each environment of normal humidity and high humidity.

[0019]

According to the present invention, a transfer material is firstly provided.
The image forming unit, the step of forming the first toner image by the first image forming means of the first image forming unit, and the first transfer bias applied to the formed first toner image. The first image forming unit
The first transfer is performed on the transfer material at the transfer section, the step of transporting the transfer material to the second image forming unit,
Forming a second toner image by the second image forming means of the second image forming unit, applying a second transfer bias to the formed second toner image, and applying a second transfer bias to the second image forming unit. A second transfer portion, a step of performing a second transfer on the transfer material on which the first toner image is transferred, and the first toner image and the second toner transferred on the transfer material. In an image forming method including a step of fixing an image on the transfer material by a fixing unit, a length of the transfer material in a transport direction is longer than a distance between the first transfer portion and the second transfer portion. , The first transfer bias and the second transfer bias are different in size, and the first toner forming the first toner image and the second toner forming the second toner image are different from each other. All the toners have SF-1 of 100 to 180 and SF.
-2 has a shape factor of 100 to 140. The present invention relates to an image forming method.

The present invention also provides (i) first toner image forming means for forming a first toner image and the first toner image forming means.
The first toner image formed by the image forming means of
Image forming unit having a first transfer unit for applying a transfer bias of No. 1 to transfer to the transfer material at the first transfer unit, and (ii) a second image forming unit for forming a second toner image.
A second transfer bias is applied to the second toner image formed by the toner image forming unit and the second image forming unit, and the first toner image is transferred by the second transfer unit. Second image forming means having a second transfer means for transferring to the transfer material, (iii) the first toner image and the second toner image transferred to the transfer material to the transfer material An image forming apparatus comprising at least a fixing unit for fixing, and (iv) a transfer unit for sequentially transferring the transfer material to the first image forming unit, the second image forming unit, and the fixing unit. , The length of the transfer material in the transport direction is longer than the distance between the first transfer portion and the second transfer portion, and the magnitudes of the first transfer bias and the second transfer bias are large. Are different from each other, and the first toner forming the first toner image And the second toner forming the second toner image has a shape factor of 100 to 180 for SF-1 and 100 to 140 for SF-2. .

[0021]

DETAILED DESCRIPTION OF THE INVENTION As a result of earnest studies, the present inventors
A step of transporting the transfer material to the first image forming unit and forming a first toner image by the first image forming means of the first image forming unit, and forming the first toner image into the first image.
Is applied to the first transfer portion of the first image forming unit to perform the first transfer on the transfer material, and the transfer material is conveyed to the second image forming unit. A step of forming a second toner image by the second image forming means of the second image forming unit;
Is applied to the second transfer portion of the second image forming unit to perform second transfer on the transfer material on which the first toner image is transferred, and In the image forming method, the first toner image and the second toner image transferred onto the transfer material are fixed to the transfer material by fixing means,
The length of the transfer material in the conveying direction is longer than the distance between the first transfer portion and the second transfer portion, and the magnitude of the first transfer bias and the second transfer bias is large. If the toners have a shape factor of SF-1 of 100 to 180 and SF-2 of 100 to 140, it is found that there is a great effect on the above problems. .

That is, the toner having a shape factor of SF-1 of 100 to 180 and SF-2 of 100 to 140 used in the present invention is excellent in transfer efficiency, and therefore, a transfer bias of a good transfer state can be obtained. It is possible to widen the setting latitude, and for example, (i) the interval between the transfer parts is narrowed so that the interval between the first transfer part and the second transfer part is shorter than the length of the transfer material in the transport direction, which is preferable. Is 11
Even when the entire image forming apparatus is made compact by setting it to 0 mm or less, more preferably 100 mm or less, the transfer material is transferred at the second transfer portion before and after passing through the first transfer portion, especially under high temperature and high humidity. Even if the transfer bias that substantially acts on the toner fluctuates, the change in the transfer efficiency of the toner in the second transfer portion is small; or (ii) the transfer bias output applied to the second transfer portion is the most preferable transfer efficiency. By setting the temperature lower than the condition obtained, it is difficult for the transfer bias to substantially change on the toner transferred at the second transfer portion before and after the transfer material passes through the first transfer portion under high temperature and high humidity. To the extent
The first transfer bias output applied to the first transfer portion and the second transfer bias output
Even if the difference from the second transfer bias output applied to the second transfer portion is reduced, the transfer efficiency of the toner at the second transfer portion is less reduced; therefore, before and after the transfer material passes through the first transfer portion. There is little change in the transfer state at the second transfer portion, the image uniformity on the same transfer material is excellent, and the change in color tone of the color image obtained under each environment of normal temperature and normal humidity and high temperature and high humidity It is possible to reduce the size of the image forming apparatus main body and reduce the size thereof.

Further, since the toner having a specific shape factor used in the present invention is excellent in lubricity, when it is used in an image forming process in which a cleaning member is brought into contact with the surface of the photoconductor, it is exposed to light. The frictional force between the body and the cleaning member can be reduced, wear on the surface of the photoconductor can be suppressed, and a smaller-diameter photoconductor drum can be used.

Further, the toner having a specific shape factor used in the present invention is the first toner which has already been transferred onto the transfer material when the second toner image is transferred at the second transfer portion. It is possible to suppress the occurrence of so-called retransfer in which an image is transferred to the photoconductor as the latent image carrier of the second image forming unit.

In particular, as described above, when the setting of the second transfer bias applied to the second transfer portion is lowered, the second transfer portion of the first toner image transferred onto the transfer material is transferred to the second transfer portion. Occurrence of retransfer can be suppressed, and therefore, the retransfer suppressing effect due to the shape of the toner and the retransfer suppressing effect due to the transfer bias applied to the second transfer portion are combined, so that the retransfer suppressing effect is more excellent. .

Further, as described above, the toner having a specific shape factor of the present invention is excellent in transfer efficiency,
(I) It becomes possible to downsize the cleaner that collects the toner remaining on the photoconductor after transfer, or (i
i) It can be adopted in an image forming method of a so-called simultaneous development cleaning system in which the developing unit also has a function as a cleaning unit for collecting and cleaning the toner remaining on the photoconductor after transfer, which will be described later, during development. However, since it is not necessary to separately provide a cleaner for collecting the toner remaining on the photoconductor after the transfer, the image forming apparatus can be made more compact in any case.

In the present invention, the shape factor of the toner is S
F-1 is 100 to 180, preferably 100 to 160,
More preferably in the range of 100 to 140, SF-
2 is preferably in the range of 100 to 140, preferably 100 to 135, and more preferably 100 to 120.

When the toner shape factor SF-1 exceeds 180 or SF-2 exceeds 140, the toner transfer efficiency decreases, the toner retransfer rate increases, and the latent image carrier surface is worn. This is not preferable because the amount tends to increase.

SF-1 and SF-2 indicating the shape factor of the toner used in the present invention are FE-SEM (S
-800), 100 toner images of 1000 to 3000 magnification are randomly sampled, and the image information is introduced into the image analysis device (Luzex3) manufactured by Nikole Co. through the interface and analyzed to calculate from the following formula. The value obtained was defined.

[0030]

[Outside 1] (AREA: toner projected area, MXLNG: absolute maximum length, PERI: circumference)

The reason why the toner having a specific shape factor used in the present invention has lubricity and can suppress abrasion of the surface of the photoconductor, is excellent in transfer efficiency, and is excellent in suppressing retransfer rate will be described below.

The shape factor SF-1 of the toner shows the degree of sphere, and as it increases from 100, it gradually changes from a spherical shape to an irregular shape. SF-2 indicates the degree of unevenness, and as the number increases from 100, the unevenness of the toner surface becomes remarkable.

In the present invention, the shape factor is set to 100 to 180 for SF-1 and 100 to 140 for SF-2 to make the shape of the toner spherical and to make the surface smooth.
The frictional force between the photoconductor drum and the cleaning member can be reduced, and the photoconductor drum can be prevented from being worn.

FIG. 2 shows the correlation between the shape factor and lubricity. For the measurement, apply the toner on the glass and
Urethane rubber with a weight of 00 g was put on it, and the load that started to move when pulled from the lateral direction was measured. From this figure, it is clear that the smaller the shape factor, the higher the lubricity.
Even when the test was actually carried out on the apparatus, abrasion of the photosensitive drum was extremely small, and it was possible to achieve a long life.

Further, the toner having a small shape factor is advantageous in terms of transferability. That is, since the contact area with the photosensitive drum is reduced, the adhesive force is reduced, and the transfer can be performed with high efficiency.

FIG. 3 shows the correlation between transfer efficiency and shape factor. From this figure, the smaller the shape factor, the higher the transfer efficiency, and as a result, the transfer residual toner collected in the cleaner becomes extremely small, and the cleaner device can be downsized.

Further, in the case of the toner used in the image forming apparatus using the simultaneous cleaning system for development, it is necessary to reduce the toner remaining on the photosensitive member after transfer to an extremely small amount. In this case, SF-1 is 100 to 140 and SF-2 is 100.
It is especially preferable that it is 120.

Further, by using a spherical and smooth surface toner, (i) the charge of the toner after being transferred to the transfer material is constant, and (ii) the toner is excessively contacted with the photoreceptor. Since the toner surface is evenly charged, the toner surface has many irregularities.
-2 has a smaller mirroring force than the toner having a large size and has a small contact area with the surface of the photoconductor. Since the toner is small, the adhesive force to the photosensitive member is small, and due to the effects of (i) and (ii), the toner transferred to the transfer material transferred from the previous (first) by the image forming unit is In the (second) image forming unit, it is possible to suppress development of retransfer electrostatically transferred to the photosensitive drum. As a result, the toner on the transfer material is not disturbed, a high-quality image is obtained, and it is possible to reduce the change in the color tone of the color image in the high humidity environment as compared with the normal temperature environment.

As a transfer means for transferring the toner image to the transfer material at the transfer portion, a non-contact transfer means using corona discharge or a contact transfer member such as a blade or a roller is contacted with the back surface of the transfer material. It is possible to use any of the contact transfer means for transferring the toner image by doing so, but in the present invention, since the interval between the transfer parts is narrowed,
The contact transfer means, in which the transfer bias applied to the transfer portion is more likely to be concentrated in the transfer portion, is more preferable than the non-contact transfer means in which the transfer bias applied to the transfer portion is likely to diffuse, because the transferability and the amount of ozone generated can be suppressed.

Further, in the present invention, a plurality of image forming units are provided and a plurality of transfer parts are also present, and the transfer material is successively conveyed to the plurality of transfer parts and transferred at each transfer part. Since multiple transfer is performed on the material, it is preferable to set the transfer bias output to be higher at the transfer portion located on the downstream side in the transport direction of the transfer material.

In the present invention, the transfer bias output means a value obtained by multiplying the voltage value (v) applied during transfer by the current value (μA).

As a method of increasing the transfer bias output, it is possible to suppress the voltage value (v) and the current value (μA) applied during transfer, or both.

Therefore, by changing the magnitudes of the transfer bias output at the first transfer portion and the transfer bias output at the second transfer portion, the transfer at the first transfer portion causes the second bias as described above. The problem that the transfer bias that substantially acts on the second toner at the transfer portion of the first toner is reduced is suppressed.
It is possible to reduce the difference between the transfer bias that substantially acts on the first toner at the transfer portion and the transfer bias that substantially acts on the second toner at the second transfer portion.

In the present invention, either a non-contact charging means such as corona discharge or a contact charging means such as a roller or a blade may be used as the charging means for the primary charging of the photoreceptor which is the latent image carrier. It is possible.

In the present invention, it is particularly preferable to use the contact charging means in terms of the effect of suppressing the ozone generation amount.

In the image forming method of the simultaneous development cleaning system, the contact charging means is used as the transfer means because a cleaner having a cleaning means for bringing the toner existing on the photoreceptor after the transfer into contact with the photoreceptor is not separately provided. In this case, since the toner existing on the photoconductor after the transfer is brought into pressure contact with the photoconductor by the contact charging means, the toner is fused on the surface of the photoconductor, and the surface of the photoconductor is further cleaned by the cleaning means. Since the toner is not ground, fusion of the toner is accumulated, and filming is likely to occur on the surface of the photoconductor.

However, since the toner used in the present invention is a toner having a spherical shape and a smooth surface having a specific shape factor, the contact charging means is used in the image forming method of the above simultaneous development cleaning system. It is particularly effective when used in an image forming method in which the above are combined.

That is, the toner used in the present invention is
Since the transfer efficiency is high and the re-transfer rate is low, the amount of toner existing on the photoconductor after transfer is small, the surface of the photoconductor is not easily damaged, and the contact area between the photoconductor and toner is small. It is possible to suppress the occurrence of fusion and filming on the photoconductor.

This effect is particularly effective when a small-diameter photosensitive drum used for downsizing the entire image forming apparatus is used.

This is because when the photosensitive drum has a small diameter, the contact area between the photosensitive drum and the contact charging means decreases, so that stress concentrates at this contact portion, so that toner fusion or filming on the surface of the photosensitive member occurs. Is likely to occur.

The toner having a specific shape coefficient used in the present invention can form an excellent image even under such a condition that toner fusion or filming on the surface of the photoconductor is likely to occur. .

The diameter of the photosensitive drum used in the present invention is preferably 20 to 40 mm in order to make the entire apparatus compact. If it exceeds 40 mm, the size of the device cannot be reduced so much, and if it is less than 20 mm, matching with other devices such as development and cleaning becomes difficult.

The photoconductor drum used in the present invention has a substance having fluorine atoms and / or silicon atoms on the surface thereof, and has an X-ray photoelectron spectrometer (XPS).
It is particularly preferable that the ratio according to the above condition satisfies the following condition F / C = 0.03 to 1.00 Si / C = 0.03 to 1.00.

The fluorine-containing photoconductor has the effect of lowering the surface energy, so that the frictional force between the photoconductor drum and other members can be reduced, which is particularly preferable for the image forming method of the present invention. The effect of fluorine can be expected even for a photoreceptor containing silicon.

Specifically, at least a binder resin,
Further, the surface layer is formed by containing a fluorine-substituted compound and / or a silicone-containing compound. The fluorine-substituted compound and / or the silicone-containing compound is at least 2
Seeds, one of which is incompatible with the binder,
The other type is compatible or emulsifiable with the binder. The two kinds of fluorine-substituted compounds and / or silicone-containing compounds coexist and are uniformly contained on the surface of the photoreceptor. As a result, the electrophotographic photosensitive member used in the present invention has a reduced surface energy, which makes it possible to solve the above-mentioned problems.

If the F / C ratio or Si / C ratio is less than 0.03, the effect of lowering the surface energy is small, and if it exceeds 1.00, the film strength and the adhesion to the lower layer are lowered.

The structure of the photosensitive drum is an electrophotographic photosensitive member having at least a photosensitive layer on a conductive substrate,
The surface layer of the photosensitive layer contains at least a binder resin and a fluorine-substituted compound and / or a silicone-containing compound to form a surface layer.

Specific examples of the fluorine-substituted compound include carbon tetrafluoride, hexafluoropropylene, trifluoroethylene, chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride, perfluoroalkyl vinyl ether and the like. Coalesce, copolymer, and graft polymer containing them in the molecule,
Block polymers and surfactants are used. In the case of incompatible and powdery fluorine-substituted compounds, the particle size is 0.0
It can be used in the range of 1 to 5 μm, and its molecular weight is 30.
It can be used in the range of 00 to 5,000,000.

Specific examples of the silicone-containing compound include a monomethylsiloxane three-dimensional crosslinked product, a dimethylsiloxane-monomethylsiloxane three-dimensional crosslinked product, an ultrahigh molecular weight polydimethylsiloxane, a block polymer containing a polydimethylsiloxane segment, a graft polymer, and an interface. Activators, macromonomers and end-modified polydimethylsiloxanes are used. In the case of a three-dimensional crosslinked product, it is used in the form of fine particles and the like, and the particle size can be used in the range of 0.01 to 5 μm. In the case of a polydimethylsiloxane compound, its molecular weight can be used in the range of 3000-5,000,000. In the case of fine particles, it is dispersed as a photosensitive layer composition together with a binder resin. As a dispersing method, a sand mill, a ball mill, a roll mill, a homogenizer, a nanomizer, a paint shaker, or an ultrasonic wave is used.
The content of the fluorine-substituted compound and / or the silicone-containing compound in the outermost surface layer of the photoreceptor is preferably 1 to 70% by weight, more preferably 2 to 55% by weight. If it is less than 1% by weight, the reduction of the surface energy is insufficient, and 7
If it exceeds 0% by weight, the film strength of the surface layer is lowered.

As the binder resin for dispersing the fluorine-substituted compound and / or the silicone-containing compound, polyester, polyurethane, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone, polyallyl ether, Examples thereof include polyacetal, nylon, phenol resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin, alkyd resin and butyral resin. Furthermore, reactive epoxy and (meth) acrylate monomers and oligomers can also be mixed and used after curing.

The photosensitive layer of the present invention contains a single layer or a laminated structure. In the case of a single layer structure, generation and transfer of photocarriers are carried out in the same layer, and the fluorine-substituted compound and / or the silicone-containing compound of the present invention are contained in this layer which is the outermost layer. In the case of a laminated structure, a charge generation layer that generates photocarriers and a charge transport layer that moves carriers are laminated. The surface layer may be formed by either the charge generation layer or the charge transport layer. In any case, the fluorine-substituted compound and / or the silicone-containing compound of the present invention is contained in the layer forming the outermost surface layer. Single layer is 5 to 1
A thickness of 00 μm is possible, more preferably 10-6.
0 μm. 20 to 8 charge generation materials and charge transport materials
The content is 0% by weight, more preferably 30 to 70% by weight. In the laminated photoreceptor, the charge generation layer has a thickness of 0.0
It is from 01 to 6 μm, more preferably from 0.01 to 2 μm. The amount of the charge generating material is 10 to 100% by weight, more preferably 40 to 100% by weight. The thickness of the charge transport layer is 5 to 100 μm, more preferably 10 to 60 μm. The amount of charge transport material is 20-80% by weight, more preferably 30-70% by weight.

The charge generating material used in the present invention includes phthalocyanine pigments, polycyclic quinone pigments, azo pigments,
Perylene pigment, isodigo pigment, quinacridone pigment, azurenium salt dye, squarylium dye, cyanine dye,
Examples thereof include pyrylium dye, thiopyrylium dye, xanthene dye, quinoneimine dye, triphenylmethane dye, styryl dye, selenium, selenium-tellurium, amorphous silicon, and cadmium sulfide.

Examples of the charge transport material used in the present invention include pyrene compounds, carbazole compounds, hydrazone compounds, N, N-dialkylaniline compounds, diphenylamine compounds, triphenylamine compounds, triphenylmethane compounds, pyrazoline compounds, styrene compounds,
Examples thereof include stilbene compounds.

In the photosensitive drum of the present invention, a protective layer may be laminated on the photosensitive layer. The thickness of the protective layer is 0.01 to 20 μm
m is possible, and more preferably 0.1 to 10 μm. The protective layer may contain the above-mentioned charge generating material or charge transporting material, metal and its oxide, nitride, salt, alloy, and conductive material such as carbon. Further, in this case, the fluorine-substituted compound and / or the silicone-containing compound of the present invention is also included in the protective layer which is the outermost surface layer.

As the binder resin used for the protective layer,
Polyester, polyurethane, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone, polyallyl ether,
Examples thereof include polyacetal, nylon, phenol resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin, alkyd resin and butyral resin. Furthermore, reactive epoxy and (meth) acrylic monomers and oligomers can be mixed and used after curing.

The conductive substrate used in the electrophotographic photosensitive member of the present invention is iron, copper, nickel, aluminum, titanium,
Metals or alloys such as tin, antimony, indium, lead, zinc, gold and silver, oxides or carbons thereof, conductive resins and the like can be used. In addition, the conductive material,
Sometimes it is molded, but it can be applied as paint,
You may vapor-deposit. An undercoat layer may be provided between the conductive substrate and the photosensitive layer. The undercoat layer is mainly composed of a binder resin, but may contain the above-mentioned conductive material or acceptor.
As the binder resin forming the undercoat layer, polyester, polyurethane, polyacrylate, polyethylene,
Polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone, polyallyl ether, polyacetal, nylon, phenol resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin,
Examples thereof include alkyd resin and butyral resin.

As the method for producing the electrophotographic photosensitive member of the present invention, methods such as vapor deposition and coating are used. For coating, bar coater, knife coater, roll coater, attritor,
Spraying, dip coating, electrostatic coating, powder coating are used.

In the present invention, when a conductive magnetic brush charger as a charging means is brought into contact with the surface of the photoconductor to directly inject charges into the photoconductor, the surface of the photoconductor contains conductive fine particles. It is preferable to form a charge injection layer.

The charge injection layer 16 is preferably made of a resin such as a photocurable acrylic resin in which conductive fine particles are dispersed in an amount of 20 to 200 parts by weight based on 100 parts by weight of the resin. As the conductive fine particles, materials such as SnO ₂ , TiO ₂ and ITO can be used. The average particle diameter of the conductive fine particles is preferably 1 μm or less, more preferably 0.5 to
The range of 50 nm is good for uniform charging.

In the present invention, the average particle size of the conductive fine particles is randomly extracted by 100 or more by a scanning electron microscope, the volume particle size distribution is calculated with the maximum chord length in the horizontal direction, and the average particle size is obtained with 50% of the average particle size. The diameter.

As a method for producing a toner having a specific shape factor used in the present invention, (i) a method of spheroidizing the toner particles obtained by the pulverization method, and (ii) a part or all of the toner Examples thereof include a method of forming by a polymerization method, and (iii) a method described in Japanese Patent Publication No. 56-13945 and the like, in which a molten mixture is atomized in air using a disk or a multi-fluid nozzle to obtain spherical toner.

The method of spheronizing the toner obtained by the pulverization method is, for example, a resin, a release agent made of a substance having a low softening point,
After uniformly dispersing the toner raw materials such as the colorant and the charge control agent using a mixer such as a Henschel mixer or a media disperser, the mixture is melt-kneaded and kneaded using a kneader such as a pressure kneader or an extruder. Toner particles are obtained by a so-called pulverization method in which an object is mechanically or collided with a target under a jet stream to be finely pulverized to a desired toner particle size, and then a particle size distribution is shampooed through a classification step to form a toner. After that, the obtained toner particles are spheronized.

As a method of spheronizing the toner particles, for example, a method of finely pulverizing using a mechanical impact type fine pulverizing apparatus or a jet type pulverizing method is used, in which the pulverizing pressure is made lower than usual and the number of circulation is increased. Examples include a method of finely pulverizing, a hot water bath method of dispersing and heating toner particles in water, a heat treatment method of passing through a hot air stream, and a mechanical impact method of applying mechanical energy for treatment.

Among these, the method of applying treatment by mechanical impact force is particularly preferable.

The treatment for applying a mechanical impact force is, for example, a method of applying a mechanical impact force to the toner by a mechanical impact type pulverizer such as a Klipstron system manufactured by Kawasaki Heavy Industries, Ltd. or a turbo mill manufactured by Turbo Industry Co., Ltd., or , Like Hosokawa Micron's Mechanofusion System and Nara Machinery's Hybridization System, centrifugally force the toner against the inside of the casing by the blades that rotate at high speed, and the toner is mechanically compressed by the action of compression force / friction force. A method of applying an impact force can be mentioned.

As a method for forming a part or all of the toner by a polymerization method, for example, JP-B-36-10231, JP-A-59-53856, and JP-A-59-6.
A method of directly producing a toner by using the suspension polymerization method described in Japanese Patent No. 1842; or a dispersion polymerization in which a toner is directly produced by using an aqueous organic solvent in which a monomer is soluble and the obtained polymer is insoluble. Or an emulsion polymerization method such as a soap-free polymerization method of directly polymerizing in the presence of a water-soluble polar polymerization initiator to produce a toner.

With regard to the toner in which at least the toner surface portion is formed by the polymerization method, since the necessary portion is formed by being present in the dispersion medium as pre-toner (monomer composition) particles by the polymerization reaction, the surface property is extremely low. It is preferable because it is close to a sphere and a smoothed product can be obtained.

Among these polymerization methods, toner shape factor SF-1 is 100 to 180 and SF-2 is 100 to 1 in particular.
The suspension polymerization method is preferred because it can be easily controlled to 40 and the particle size distribution can be relatively easily obtained to obtain a fine particle toner having a particle size of 4 to 8 μm.

In this suspension polymerization method, the polymerization can be carried out either under normal pressure or under pressure.

The particle size distribution, particle size and shape factor of the toner can be controlled by changing the type and amount of the sparingly water-soluble inorganic salt or dispersant having a protective colloid action; mechanical device conditions such as the peripheral speed of the roller. It can be performed by stirring conditions such as the number of passes and the shape of a stirring blade, the shape of a container, or a method of controlling the solid content concentration in an aqueous solution.

In the present invention, as the binder resin used in the toner, generally used styrene- (meth) acrylic copolymers, polyester resins, epoxy resins and styrene-butadiene copolymers can be used. I can. In the method of directly obtaining a toner by a polymerization method, a monomer for synthesizing the polymer is preferably used. Specifically, styrene-based monomers such as styrene, o (m-, p-)-methylstyrene, m (p-)-ethylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, (meth ) Propyl acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ( (Meth) acrylic acid ester-based monomers such as dimethylaminoethyl methacrylate and diethylaminoethyl (meth) acrylate; ene-based monomers such as butadiene, isoprene, cyclohexene, (meth) acrylonitrile, and acrylic acid amide It is preferably used. These can be used alone or in combination.

When the monomers are used in combination,
Polymer Handbook Second Edition III-P139-192
It is preferable to obtain a copolymer having a theoretical glass transition temperature (Tg) of 40 to 75 ° C. described in (John Wiley & Sons).

When the theoretical glass transition temperature is lower than 40 ° C., problems tend to occur from the viewpoint of storage stability of toner and durability stability of developer, and when it exceeds 75 ° C., the fixing point rises. In the case of full color toner, the color mixing of each color toner is insufficient, resulting in poor color reproducibility.
It is not preferable from the viewpoint of high image quality because it significantly reduces the transparency of the HP image.

The molecular weight of the resin component of the toner is measured by GPC (gel permeation chromatography). As a specific method for measuring GPC, the toner was previously extracted with a Soxhlet extractor for 20 hours using a toluene solvent, and then the toluene was distilled off with a rotary evaporator, and the ester wax was dissolved but the binder resin was Thoroughly wash by adding an insoluble organic solvent such as chloroform, and then THF (tetrahydrofuran)
The sample obtained by filtering the solution soluble in the above with a solvent-resistant membrane filter having a pore size of 0.3 μm was used as Waters 150C, and the column configuration was Showa Denko A-801.
The molecular weight distribution can be measured by connecting 802, 803, 804, 805, 806, 807 and using a calibration curve of a standard polystyrene resin. Number average molecular weight (Mn) of the obtained resin component
Is in the range of 5000 to 1,000,000, and the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (M
The w / Mn) is preferably in the range of 2 to 100 for the present invention.

As the colorant used in the toner, a yellow colorant, a magenta colorant, a cyan colorant and a black colorant are used.

As the black colorant, carbon black, a magnetic substance, and a yellow colorant, a magenta colorant and a cyan colorant shown below, which are toned black, are used.

Examples of yellow colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
A compound represented by an azo metal complex, a methine compound and an allylamide compound is used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 97, 109, 1
10, 111, 120, 127, 128, 129, 14
7, 168, 174, 176, 180, 181, 191
Is preferably used.

As the magenta colorant, a condensed azo compound, a diketopyrrolopyrrole compound, an anthraquinone, a quinacridone compound, a basic dye lake compound, a naphthol compound, a benzimidazolone compound, a thioindigo compound and a perylene compound are used. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8; 2, 48; 3, 48; 4, 57; 1, 81; 1, 1
44, 146, 166, 169, 177, 184, 18
5, 202, 206, 220, 221, 254 are preferably used.

As the cyan colorant, a copper phthalocyanine compound and its derivative, an anthraquinone compound, and a basic dye lake compound can be used. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 1
5: 3, 15: 4, 60, 62, 66 are preferably used.

These colorants can be used alone or in a mixture, and can be used in the form of a solid solution. The colorant of the present invention is selected in consideration of hue angle, saturation, brightness, weather resistance, OHP transparency, and dispersibility in toner. The amount of colorant added to the toner is 1 to 20 with respect to 100 parts by weight of the resin.
It is better to be within the range of parts by weight.

When a magnetic material is used as the black colorant, unlike other colorants, the amount of the black colorant added to the toner is within the range of 40 to 150 parts by weight with respect to 100 parts by weight of the resin. Good to have.

The charge control agent used in the present invention includes
Known charge agents can be used, but a charge control agent that is colorless and has a high toner charging speed and that can stably maintain a constant charge amount is preferable. Further, when the toner is produced by the direct polymerization method in the present invention, a charge control agent having no polymerization inhibitory property and having no solubilized product in an aqueous system is particularly preferable. As a specific compound, a negative metal compound of salicylic acid,
A metal compound of naphthoic acid, a metal compound of dicarboxylic acid, a polymer type compound having a sulfonic acid or a carboxylic acid in a side chain, a boron compound, a urea compound, a silicon compound, and curlys arene are preferably used, and a quaternary compound is used as a positive system. An ammonium salt, a polymer type compound having a side chain of the quaternary ammonium salt, a guanidine compound, and an imidazole compound are preferably used.

The amount of the charge control agent added to the toner was resin 1
0.5 to 10 parts by weight is preferable with respect to 00 parts by weight. However, the addition of a charge control agent in the present invention is not essential, in the case of using the two-component developing method, utilizing the triboelectric charging with the carrier, even in the case of using the non-magnetic one-component blade coating developing method. By positively utilizing the triboelectric charging with the member or the sleeve member, it is not always necessary to include the charge control agent in the toner.

In the present invention, when the toner is produced by the direct polymerization method, as the polymerization initiator, for example, 2,2'-
Azobis- (2,4-dimethylvaleronitrile), 2,
2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2 '
An azo or diazo polymerization initiator such as azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxy carbonate, cumene hydroperoxide, 2,4-
Peroxide type polymerization initiators such as dichlorobenzoyl peroxide and lauroyl peroxide are used. The amount of the polymerization initiator added varies depending on the intended degree of polymerization, but is generally preferably 0.5 to 20% by weight with respect to the monomer.
Although the type of the polymerization initiator varies slightly depending on the polymerization method, it may be used alone or in combination with reference to the 10-hour half-life temperature.

To control the degree of polymerization, known crosslinking agents, chain transfer agents and polymerization inhibitors may be further added and used.

In the present invention, when suspension polymerization is used as a method for producing a toner, an inorganic oxide or an organic compound can be used as a dispersant dispersed in an aqueous phase. Examples of the inorganic oxides include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide,
Examples thereof include calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina, magnetic materials, and ferrite. Examples of the organic compound include polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, and starch. These dispersants include the polymerizable monomer 10
It is preferable to use 0.2 to 2.0 parts by weight with respect to 0 parts by weight.

As these dispersants, commercially available ones may be used as they are, but in order to obtain dispersed particles having a fine and uniform particle size, the inorganic compound may be formed under high speed stirring in a dispersion medium. I can. For example, in the case of tricalcium phosphate, a dispersant suitable for the suspension polymerization method can be obtained by mixing an aqueous sodium phosphate solution and an aqueous calcium chloride solution under high speed stirring. To make these dispersants finer, 0.001 to 0.1 part by weight of a surfactant may be used in combination. Specifically, commercially available nonionic, anionic, or cationic surfactants can be used, such as sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate,
Potassium stearate and calcium oleate are preferably used.

When the direct polymerization method is used for the toner manufacturing method, the toner can be specifically manufactured by the following manufacturing method. Add a colorant, charge control agent, polymerization initiator, and other additives to the monomer, and homogenize or disperse the monomer composition that has been uniformly dissolved or dispersed by a disperser such as an ultrasonic disperser. It is dispersed in an aqueous phase containing the agent by a usual stirrer or a disperser such as a homomixer and a homogenizer. Granulation is performed by adjusting stirring conditions such as stirring speed and stirring time so that droplets of the monomer composition have a desired toner particle size. After that, stirring may be performed to the extent that the particle state is maintained and the particles are prevented from settling by the action of the dispersion stabilizer. The polymerization temperature is set to 40 ° C. or higher, generally 50 to 90 ° C. to carry out the polymerization. The temperature may be raised in the latter half of the polymerization reaction, and for the purpose of improving durability in the image forming method of the present invention, in the latter half of the reaction for removing unreacted polymerizable monomer or by-product, or in the reaction. After the completion, part of the aqueous medium may be distilled off. After the reaction,
The produced toner particles are collected by washing and filtration and dried. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer system.

The toner used in the present invention preferably has an unreacted residual monomer content of 1000 ppm or less, more preferably 500 ppm or less, and further preferably 300 ppm or less. It is preferable because it is difficult to reduce the effect and cause retransfer.

When the content of residual monomer in the toner is 100
If it exceeds 0 ppm, the residual monomer in the toner will contaminate the surface of the photoconductor and reduce the contact angle on the surface of the photoconductor in the durability of many sheets, and thus the transfer efficiency of the toner will be easily lowered, and the toner Retransfer is easily caused.

The content of the residual monomer in the toner is set to 100.
The following method can be used as the method for reducing the concentration to 0 ppm or less.

When the toner is produced by the suspension polymerization method,
For example, a method of washing with a highly volatile organic solvent which does not dissolve the toner binder resin but dissolves the polymerizable monomer and / or the organic solvent component; a method of washing with an acid or an alkali; a method of dissolving a foaming agent or a polymer. A solvent component that does not exist is added to the polymer system to make the resulting toner porous so as to increase the volatilization area of the polymerizable monomer and / or the organic solvent component inside; and the polymerizable monomer and // under reduced pressure. Alternatively, a method of volatilizing an organic solvent component may be mentioned, but since it is difficult to select a solvent such as elution of a toner constituent component due to deterioration of toner capsule properties and residual property of the solvent, the polymerizable monomer and / or the organic solvent are reduced under reduced pressure. The method of volatilizing the components is most preferable.

When the toner is manufactured by a pulverization method and then spheroidized, for example, when the binder resin of the toner is polymerized by suspension polymerization, the polymerization is carried out while introducing nitrogen gas into the suspension flow. A method in which the binder resin of the toner is synthesized by suspension polymerization, and then water is distilled from the suspension at a temperature not lower than the Tg of the resin and residual monomers are distilled; the polymerization rate is 98% or higher. A method of performing the polymerization for a long time until the temperature reaches a certain level; and a method of drying the resin under reduced pressure with heating after the completion of the polymerization reaction can be mentioned, and it is also possible to appropriately combine them.

A toner having a small residual monomer content is
As described above, it is preferable that the surface of the photoconductor can be prevented from being contaminated during the durability of a large number of sheets, and this effect is particularly effective when the organic photoconductor (OPC) is used as the photoconductor.

That is, since the organic photoconductor is formed of resin, the content of the residual monomer in the toner is particularly small because the resin is deteriorated in the case of a toner containing a large amount of residual monomer in the toner. Is required.

As described above, a toner having a residual monomer content of 1000 ppm or less in the toner is unlikely to cause a decrease in the transfer effect and an increase in the retransfer rate in the durability of a large number of sheets. It is effective when used, and is more effective when used in an image forming method using a contact charging method in which the surface of the photosensitive member is contacted with and primary charging is performed. The effect is more remarkable when it is used in the image forming method in which the residual toner is collected by the developing device at the time of development in combination with the simultaneous development developing method.

That is, in the image forming method using the contact charging method, when a large amount of toner remains on the photosensitive charging after transfer (that is, toner that has not been transferred and toner that has been retransferred), it passes through the cleaning means. As a result, the amount of toner that reaches the contact charging device also increases, so that the toner components are easily fused to the contact charging member, and this is remarkable especially in the case of a toner containing a large amount of residual monomer.

Further, in the case of the image forming method using the simultaneous cleaning system for development, since the cleaning means for removing the toner existing on the photosensitive member is not provided between the transfer portion and the contact charging device, the contact is prevented. The amount of toner reaching the charger becomes larger, so that the fusion of the toner component to the contact charging member is more likely to occur.

However, since the toner used in the present invention is a toner having a specific shape factor, high transfer efficiency, and retransfer suppressed, the amount of the toner remaining on the photosensitive member after the transfer is large. In the case of a toner containing a small amount of residual monomer in the toner, in addition to being able to suppress fusion of the toner component to the contact charging member, The fusion of the components can be further suppressed, and thus the simultaneous development cleaning method can be applied to the image forming method.

In the present invention, the method for measuring the residual monomer of the toner is as follows.

The amount of residual monomer is measured by dissolving 0.2 g of the toner in 4 ml of tetrahydrofuran (THF) and measuring by gas chromatography (GC) by the internal standard method under the following conditions.

G. C. Conditions Measuring device: Shimadzu GC-15A Carrier gas: N ₂ gas, 2 kg / cm ² , 50 ml /
min, split ratio 1:60, linear velocity 30 mm / s
ec column: ULBON HR-1 50 mm × 0.
25 mm temperature rise: 50 ° C., 5 min hold, 5 ° C. m
in, 100 ° C. 10 ° C./min, 200 ° C. hold Sample amount: 2 μl Standard sample: Toluene

The toner particles used in the present invention have a weight average particle diameter of 1 to 9 μm in order to faithfully develop an analog latent image or a minute latent image dot in order to improve the image quality.
(Preferably 2 μm to 8 μm). Further, it is preferable that the toner particles have a variation coefficient (A) in the number distribution of 35% or less. In the case of toner particles having a weight average diameter of less than 1 μm, a large amount of toner particles remain after transfer on an electrostatic image carrier such as a photoconductor due to a decrease in transfer efficiency, and further, unevenness in image due to fog and transfer failure occurs. It is not preferred as the toner used in the present invention because it easily causes the problem. When the weight average diameter of the toner particles exceeds 9 μm, fusion with a member such as the surface of the photoconductor is likely to occur. If the variation coefficient in the number distribution of toner particles exceeds 35%, the tendency becomes stronger.

The particle size distribution of toner particles can be measured by various methods. In the present invention, a Coulter counter is used.

For example, a Coulter Counter TA-II type (manufactured by Coulter) or a Coulter Multisizer (manufactured by Coulter) is used as a measuring device, and an interface (manufactured by Nikkaki Co., Ltd.) for outputting number distribution and volume distribution and CX-1 Personal are used. The computer (manufactured by Canon) is maintained and the electrolyte is approximately 1% Na using primary sodium chloride.
An aqueous Cl solution is prepared. For example, ISOTON II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, the electrolytic aqueous solution is 100 to 150 m.
0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) as a dispersant is added to 1 l, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and, for example, 100 μaperture or 50 μaperture is used as an aperture by the Coulter Counter TA-II type. ~ 40μ (or 1-20
The particle size distribution of the particles of μ) is measured and the value according to the invention is then determined.

Coefficient of variation A in number distribution of toner particles
Is calculated from the following formula.

Coefficient of variation A = [S / D ₁ ] × 100 [wherein, S represents a standard deviation value in the number distribution of toner particles, and D ₁ represents a number average particle diameter (μm) of the toner particles. ]

For the toner used in the present invention, it is preferable to use a fine powder having a function as a fluidity improver for toner particles as an external additive mixed with the toner particles.

The external additive used in the present invention preferably has a particle diameter of 1/10 or less of the weight average particle diameter of the toner particles from the viewpoint of durability when added to the toner. The particle diameter of the external additive has the average particle diameter obtained by observing the surface of the toner particles (50,000 times) with an electron microscope. Examples of the external additive include metal oxides (aluminum oxide, titanium oxide, strontium titanate, cerium oxide, magnesium oxide, chromium oxide, tin oxide, zinc oxide, etc.); nitrides (silicon nitride, etc.); carbides ( Silicon carbide, etc .; metal salts (calcium sulfate, barium sulfate, calcium carbonate, etc.); fatty acid metal salts (zinc stearate, calcium stearate, etc.); carbon black; silica fine powder.

The fine powder used as the external additive preferably has hydrophobicity, and the hydrophobicity is preferably 60% or more, more preferably 80% or more, further preferably 90%.
The above is good.

As the hydrophobicity of the fine powder as an external additive in the present invention, a value measured by the following method is used. It is possible to apply other measuring methods while referring to the measuring method of the present invention.

100 ml of ion-exchanged water and 0.1 g of a sample were placed in a 200 ml separating funnel of a sealed stopper type, and the mixture was shaken (Turbra shaker mixer T2C type) at 90 rpm.
Shake for 10 minutes under the above conditions. After shaking, the mixture was allowed to stand for 10 minutes to separate the inorganic powder layer and the aqueous layer, and then the lower aqueous layer was added to 20
〜30ml is sampled, put in a 10mm cell, and the transmittance is measured at the wavelength of 500nm with reference to the blank ion-exchanged water without the fine powder. The value of the transmittance is used as the hydrophobicity of the inorganic fine powder. is there.

The degree of hydrophobicity of the fine powder as an external additive is 60%
When the amount is less than the above range, the transfer efficiency is lowered due to the decrease in the charge amount of the toner and the decrease in the fluidity of the toner due to the absorption of moisture particularly in a high humidity environment, and the toner scattering and the fogging are likely to occur.

As the method for hydrophobizing the fine powder, it is possible to use the method for hydrophobizing the inorganic fine powder a and the silicon compound b described later.

In the present invention, the external additive is toner particles 1.
It is preferably used by mixing with 0.1 to 5 parts by weight, more preferably from 0.2 to 4 parts by weight of toner particles, relative to 00 parts by weight.

When the amount of the external additive added is less than 0.1 parts by weight, the fluidity imparting ability to the toner particles is insufficient, and when it exceeds 5 parts by weight, the external additive liberated from the toner particles is added. Tend to contaminate the carrier and the developing sleeve, and the chargeability of the toner tends to decrease.

Since the toner used in the present invention is spherical and has a smooth surface, the toner has a contact area when the toner particles contact each other in the developing device or when the toner particles contact the developing sleeve or carrier particles. Since the stress is small and the stress is likely to be concentrated, the problem that the external additive mixed with the toner particles is embedded in the toner particles is likely to occur, and the durability of the toner is apt to be lowered.

Therefore, in the present invention, the hydrophobic inorganic fine powder a and the hydrophobic silicon compound b having a larger particle size than the hydrophobic inorganic fine powder a are used in combination as an external additive. Is particularly preferable.

In the present invention, when a combination of a hydrophobicized inorganic fine powder a and a hydrophobicized silicon compound b having a larger particle size than the inorganic fine powder is used as an external additive,
The hydrophobicized inorganic fine powder a has an average particle diameter of 3 to 90 nm.
The average particle size of the hydrophobized silicon compound b is 30 to 120 nm, and the particle size is 5 to 3
Containing 15 to 45% by number of 0 nm silicon compound particles,
30 to 70% by number of silicon compound particles having a particle size of 30 to 60 nm are contained, and 5 silicon compound particles having a particle size of 60 nm or more are included.
It is preferable to have a wide particle size distribution containing 45% by number.

When a combination of the hydrophobized inorganic fine powder a and the hydrophobized silicon compound b is used as an external additive, the matrix of the hydrophobized inorganic fine powder a is titanium oxide or oxide. Aluminum, strontium titanate,
Metal acid compounds such as cerium oxide and magnesium oxide;
Examples thereof include nitrides such as silicon nitride; carbides such as silicon carbide; metal salts such as calcium sulfate, barium sulfate and calcium carbonate; carbon fluoride. Of these, titanium oxide is more preferable, and a method for producing titanium oxide includes a method of vapor-phase oxidizing a titanium halogen compound or a titanium alkoxide. Titanium oxide may be either crystalline (anatase type, rutin type) or amorphous.

As the method for hydrophobizing the inorganic fine powder a, either a wet method or a dry method may be used.

Examples of the hydrophobizing agent include silane coupling agents, titanium coupling agents, aluminate coupling agents, zircoaluminum coupling agents and silicone oils. Particularly preferably used is a silane coupling agent having a general formula R _m SiY _n [wherein, R represents an alkoxy group, Y represents an alkyl group,
A hydrocarbon group such as a vinyl group, a glycidoxy group, and a methacryl group is shown, m is an integer of 1 to 3, and n is an integer of 1 to 3. ] The thing represented by the integer of n: 1-3 is mentioned. Among the silane coupling agents, monoalkyltoalkoxysilane coupling agents are particularly preferable.

Specific examples of the silane coupling agent include:
Vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyl Triethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, hydroxypropyltrimethoxysilane, phenyltrimethoxysilane, n
-Hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane, n-butyltrimethoxysilane,
Examples include n-octyltrimethoxysilane.

The treatment amount of the hydrophobizing agent is preferably 1 to 50 parts by weight, more preferably 3 to 40 parts by weight, based on 100 parts by weight of the fine powder or the inorganic fine powder a. When the amount of treatment is less than 1 part by weight, the effect of hydrophobization is small, the leakage of charging is quick under high humidity, and the charging stability of the toner is lowered. When the treatment amount exceeds 50 parts by weight, the generation of coarse secondary particles is promoted, and the effect of improving the fluidity is likely to decrease.

The average particle size of the fine powder or the hydrophobized inorganic fine powder a and the hydrophobized silicon compound b was determined by taking a photograph of 50,000 parts of the inorganic fine powder with a scanning electron microscope (manufactured by Hitachi, Ltd.). , LUZEX III (manufactured by Nireco) to measure the diameter of 100 or more particles having a particle diameter of 5 nm or more, and obtain an average value.

The hydrophobicity of the inorganic fine powder a is preferably 60% or more, more preferably 80% or more, still more preferably 90% or more.

When the degree of hydrophobicity of the inorganic fine powder a is less than 60%, the transfer efficiency is lowered due to a decrease in the charge amount of the toner and a decrease in the fluidity of the toner due to moisture absorption especially in a high humidity environment. Toner scattering and fog are likely to occur.

The hydrophobized inorganic fine powder a has an absolute value of triboelectric charge amount of 45 mC / k measured using an iron powder carrier.
It is preferably g or less (more preferably 30 mC / kg or less) from the viewpoint of stability of the charge amount of the small particle size toner.

The triboelectric charge amount of the hydrophobized inorganic fine powder is
Hydrophobicized inorganic fine powder a2 parts by weight and iron powder carrier (for example, iron powder carrier EFV- manufactured by Powder Tech Co., Ltd.
200/300) 98 parts by weight and shaken 300 to 400 times in a polyethylene container, and then measured in the same manner as the measurement of the triboelectric charge amount of the toner described below.

Further, the hydrophobized inorganic fine powder a has a BET specific surface area of 100 to 30 measured using nitrogen gas.
It is preferably 0 m ² / g in order to efficiently improve the fluidity of the toner particles.

Hydrophobicized inorganic fine powder a in the present invention
Is preferably used in an amount of 0.05 to 3.5 parts by weight, more preferably 0.1 to 2.0 parts by weight, based on 100 parts by weight of the toner particles. If the addition amount is less than 0.05 parts by weight, the fluidity imparting property to the toner particles is deteriorated. If the addition amount exceeds 3.5 parts by weight, the particles liberated from the toner particles are likely to contaminate the surface of the carrier and the developing sleeve, and as a result, the charge amount of the toner is likely to decrease.

Next, the hydrophobized silicon compound fine powder used for preventing or suppressing the above-mentioned hydrophobized inorganic fine powder a from being embedded in the toner particle surface will be described.

As the matrix of the hydrophobized silicon compound fine powder b, silica fine powder or silicone resin fine powder is preferable. As the silica fine powder b, a fine powder in which inorganic fine particles other than silica are used as the core and the surface is made of silica may be used.

Examples of the method for producing fine silica powder include vapor phase oxidation of a silicon halogen compound and a sol-gel method.

For hydrophobizing the silicon compound, a silane coupling agent and silicone oil are preferable as the hydrophobizing agent. As the silane coupling agent, hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyl Dimethylchlorosilane,
α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1, Examples thereof include 3-divinyltetramethyldisiloxane and 1,3-diphenyltetramethyldisiloxane.

A nitrogen-containing silane coupling agent may be used to impart a positive triboelectric charging property to the hydrophobized silicon compound fine powder. As the nitrogen-containing silane coupling agent, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane,
Monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl-γ-propylphenylamine, trimethoxysilyl-γ -Propylbenzylamine and the like.

Examples of the silicone oil include those represented by the following formula.

[0148]

[Outside 2] [Wherein R represents a C _1-3 alkyl group, R ′ represents a silicone oil-modified group such as alkyl, halogen-modified alkyl, phenyl, and modified phenyl, and R ″ represents a C _1-3 alkyl group or an alkoxy group. Group is shown.]

Examples thereof include dimethyl silicone oil, alkyl-modified silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil. The silicone oil preferably has a viscosity at 25 ° C. of 50 to 100 centistokes.

A nitrogen-containing silicone oil may be used for imparting hydrophobicity and positive triboelectric charging properties to the hydrophobized silicon compound fine powder.

As the silicone oil having a nitrogen atom in the side chain, a silicone oil having at least a partial structure represented by the following formula can be used.

[0152]

[Outside 3] (In the formula, R ₁ represents hydrogen, an alkyl group, an aryl group or an alkoxy group, R ₂ represents an alkylene group or a phenylene group, R ₃ and R ₄ represent hydrogen, an alkyl group or an aryl group, and R ₅ Represents a nitrogen-containing heterocyclic group.)

The above-mentioned alkyl group, aryl group, alkylene group and phenylene group may have an organo group having a nitrogen atom, or have a substituent such as halogen within a range not impairing the charging property. May be.

The amount of the hydrophobizing agent used in the hydrophobizing treatment is 1 part with respect to 100 parts by weight of the silicon compound fine powder.
˜50 parts by weight, more preferably 2-35 parts by weight. Hydrophobicity is 30 to 80%, more preferably 35 to 7
5% is preferable.

Hydrophobicized silicon compound fine powder b
The hydrophobic fine inorganic powder a used for remarkably improving the fluidity of the toner particles is often buried in the surface of the toner particles, and it is preferable to use particles containing coarse particles.

The hydrophobized silicon compound fine powder b used in the present invention has an average particle size of 30 to 120 nm,
15-45% by number (preferably 20-40% by number) of silicon compound particles having a wide particle size distribution and a particle size of 5-30 nm.
30 containing silicon compound particles having a particle size of 30 to 60 nm
To 70% by number (preferably 45 to 70% by number, more preferably 50 to 70% by number), and 5 to 45% by number (preferably 10) of silicon compound particles having a particle diameter of 60 nm or more.
(About 40% by number) is preferable.

The amount of the hydrophobized silicon compound b used in the present invention is 0.0 based on 100 parts by weight of the toner particles.
The amount is preferably 5 to 3.5 parts by weight, more preferably 0.1 to 2.0 parts by weight.

The hydrophobized silicon compound fine powder b satisfactorily prevents the fluidity-improving agent from being buried in the surface of the toner particles, and further enhances the transfer rate of the toner image in the transfer step, and in the cleaning step. It is possible to satisfactorily remove the residual small-sized toner particles of (3) from the electrostatic image carrier. The above effect is presumed to be because the silicon compound fine powder b contains coarse particles having a large particle diameter, the coarse particles are hard to be buried in the toner particle surface, and the coarse particles function as a spacer. Furthermore, when using a hydrophobized silicon compound fine powder having a larger triboelectric charge absolute value than the fluidity improver, it is more closely adhered to the toner particles than the fluidity improver and It is possible to prevent the embedding of the improver on the surface of the toner particles even better.

The hydrophobized silicon compound fine powder b was measured by using nitrogen gas in order to better prevent the hydrophobized inorganic fine powder which functions as a fluidity improver from being embedded in the toner particle surface. Has a BET specific surface area of 80 m ² / g
Or less (more preferably 70 m ² / g or less), and the absolute value of the triboelectric charge amount with respect to the iron powder carrier is 50 to 300.
mC / kg (more preferably 70 to 250 mC / k
g) is good.

Hydrophobicized inorganic fine powder a in the present invention
The effect of the combined use with the hydrophobized silicon compound fine powder b becomes more remarkable as the values of the shape factors SF-1 and SF-2 of the toner particles approach 100.

The toner of the present invention can be usually used as a one-component developer or a two-component developer.

As the one-component developer, in the case of a magnetic toner in which a magnetic material is contained in toner particles, there is a method of using a magnet incorporated in a developing sleeve to convey and charge the magnetic toner. . When a non-magnetic toner containing no magnetic substance is used, there is a method in which a blade or a roller is used, and the toner is forcibly charged by friction with a developing sleeve so that the toner adheres to the sleeve to carry the toner.

When used as a two-component developer,
A carrier is used with the toner of the present invention. The magnetic carrier is composed of an element consisting of iron, copper, zinc, nickel, cobalt, manganese, and chromium elements alone or in a composite ferrite state. The shape of the magnetic carrier is spherical, flat, or amorphous. Further, it is preferable to control the fine structure (for example, surface irregularity) of the surface state of the magnetic carrier particles. Generally, a method is used in which the above-mentioned inorganic oxide is fired and granulated to generate magnetic carrier core particles in advance and then coated on a resin. From the viewpoint of reducing the load on the toner of the magnetic carrier, after kneading the inorganic oxide and the resin, pulverizing and classifying to obtain a low-density dispersed carrier, and further, directly kneading the inorganic oxide and the monomer It is also possible to use a method of obtaining a spherical spherical magnetic carrier by suspension polymerization in an aqueous medium.

A resin-coated carrier in which the surface of the carrier particles is coated with a resin is particularly preferable. As a coating method, a method in which a resin is dissolved or suspended in a solvent and applied to and adhered to carrier particles, or a method in which a resin powder and carrier particles are simply mixed and adhered can be applied.

The substance adhered to the surface of the carrier particles varies depending on the toner material, and examples thereof include polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, styrene resin, acrylic resin and polyacid. , Polyvinyl butyral, and amino acrylate resin. These are used alone or in plural.

The magnetic properties of the carrier are preferably as follows.
The strength of magnetization (1000) at 1000 Oersted after magnetically saturating is 30 to 300 emu / c.
m ³ is required. To achieve higher image quality, preferably 100 to 250 emu / cm ³
Be good. If it is higher than 300 emu / cm ^3, it becomes difficult to obtain a high-quality toner image. 30
If it is less than nu / cm ³ , carrier adhesion is likely to occur because the magnetic restraining force is also reduced.

The carrier shape is SF1 indicating the degree of roundness.
Is 180 or less, and SF2 indicating the degree of unevenness is preferably 250 or less. In addition, SF-1 and SF-2 are defined by the following formulas, and LVZEX III manufactured by Nireco Co., Ltd.
Is measured at.

[0168]

[Outside 4]

When a two-component developer is prepared by mixing the toner of the present invention with a magnetic carrier, the mixing ratio is 2% by weight to 15% by weight, preferably 4% by weight to the toner concentration in the developer. 13% by weight usually gives good results.

An image forming method and an image forming apparatus using the toner of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic view of an image forming apparatus capable of carrying out the image forming method of the present invention.

The image forming apparatus main body is provided with a first image forming unit Pa, a second image forming unit Pb, a third image forming unit Pc and a fourth image forming unit Pd.
Images of different colors are formed on the transfer material through the processes of latent image, development and transfer.

The structure of each image forming unit provided in the image forming apparatus will be described by taking the first image forming unit Pa shown in FIG. 4 as an example.

The first image forming unit Pa has an electrophotographic photosensitive drum 1a as a latent image carrier, and the photosensitive drum 1a is rotated in the direction of arrow a. Reference numeral 2a is a primary charger as a charging means, which is a photosensitive drum 1a.
A non-contact corona charger is used. 17a is
It is a polygon mirror that scans by rotating a laser beam as a latent image forming means for forming an electrostatic latent image on the photosensitive drum 1a whose surface is uniformly charged by the primary charger 2a. Reference numeral 3a is a developing device as a developing means for developing the electrostatic latent image carried on the photosensitive drum 1a to form a color toner image, and holds the color toner. Reference numeral 4a denotes a bed-shaped transfer material carrier 8 for forming a color toner image formed on the surface of the photosensitive drum 1a.
Is a transfer blade as a transfer means for transferring to the surface of the transfer material 6 conveyed by the transfer material. The transfer blade 4a is in contact with the back surface of the transfer material carrier 8 and can apply a transfer bias. .

Reference numeral 5a is a cleaning means for removing the color toner remaining on the surface of the photosensitive drum 1a after the transfer, and the cleaning means 5a is the photosensitive drum 1a.
It has a cleaning blade for coming into contact with the surface of the above to remove the color toner and a cleaner for collecting and holding the removed color toner. 21a is the photosensitive drum 1
It is an erase exposure device as a charge removing means for removing the charge on the surface of a.

In the first image forming unit 1a, after the primary charger 2a uniformly charges the photosensitive body of the photosensitive drum 1a to form a primary image, the latent image forming means 17a forms an electrostatic latent image on the photosensitive body. A belt shape that develops the electrostatic latent image with the color toner by the developing device 3a, and carries and conveys the developed toner image with the transfer material b at the first transfer portion (contact position between the photoconductor and the transfer material). The transfer material is transferred to the surface of the transfer material 6 by applying a transfer bias from the transfer blade 4a that contacts the back surface side of the transfer material carrier 8.

The color toner existing on the photoconductor is removed from the photoconductor by the cleaning blade of the cleaning means 5 and collected by the cleaner. The photoconductor is discharged by the erase exposure device 21a, and the image forming process is performed again. Done.

As shown in FIG. 1, the image forming apparatus of the present invention has the same structure as that of the first image forming unit Pa as described above, and the second color toner held in the developing device has a different color. Image forming unit Pb, third image forming unit Pc, and fourth image forming unit Pd. For example, the first
The magenta toner is used for the image forming unit Pa, the cyan toner is used for the second image forming unit Pb, the yellow toner is used for the third image forming unit Pc, and the black toner is used for the fourth image forming unit. At the transfer portion, the transfer of each color toner onto the transfer material is sequentially performed. In this step, the color toners are superposed on the same transfer material by one movement of the transfer material while the registration is adjusted, and when completed, the transfer material 6 is separated from the transfer material carrier 8 by the separation charger 14. Then, it is sent to the fixing device 7 by a carrying means such as a carrying belt, and the final full-color image is obtained by only one fixing.

The fixing device 7 has a pair of fixing roller 71 and pressure roller 72, and both the fixing roller 71 and pressure roller 72 have heating means 75 and 76 inside. Reference numerals 73 and 74 are webs for removing dirt on the fixing rollers, and reference numeral 77 is an application roller as an oil application means for applying a releasing oil 78 such as silicone oil to the surface of the fixing roller 71.

The unfixed color toner image transferred onto the transfer material 6 passes through the pressure contact portion between the fixing roller 71 and the pressure roller 72 of the fixing device 7, and the transfer material is subjected to the action of heat and pressure. It is fixed on 6.

Incidentally, in FIG. 1, the transfer material carrier 8 is an endless belt-shaped member, and this belt-shaped member is moved in the direction of arrow e by 10 driving rollers. Reference numeral 9 is a transfer belt cleaning device, 11 is a belt driven roller, and 12 is a belt static eliminator. Reference numeral 13 denotes a pair of registration rollers 13 for conveying the transfer material 6 in the transfer material holder 60 to the transfer material carrier 8. Reference numeral 17 denotes a polygon mirror, and an fθ lens for scanning laser light emitted from a light source device (not shown) by this polygon mirror and converging the scanning light whose light flux is deflected by the reflection mirror on the generatrix of the photosensitive drum. A latent image is formed according to the image signal.

In the present invention, as the charging means for the primary charging of the photosensitive member, a non-contact charging member for charging the photosensitive member in a non-contact manner such as a corona charger and a photosensitive member such as a roller, a blade or a magnetic brush. It is possible to use any contact charging member that comes into contact with and is charged, but it is preferable to use the contact charging member because the amount of ozone generated during charging can be suppressed.

As the transfer means, contact transfer capable of directly applying a transfer bias by contacting the back surface side of the transfer material carrier such as a roller-shaped transfer roller instead of the transfer blade contacting the back surface side of the transfer material carrier. Means can be used.

Further, instead of the above contact transfer means, a contact bias is applied from a corona charger, which is arranged in non-contact on the back side of a transfer material carrier which is generally used, to perform transfer by non-contact. It is also possible to use the above transfer means.

However, it is more preferable to use the contact transfer means because the amount of ozone generated when the transfer bias is applied can be suppressed.

The structure of the contact charging member usable in the present invention will be described in detail with reference to the drawings.

FIG. 5 is a schematic diagram of a charging roller as a contact charging member usable in the present invention. Reference numeral 1 denotes a photosensitive drum as a latent image carrier, which is formed by forming an organic photoconductor (OPC) 102b as a photosensitive layer on the outer peripheral surface of a drum base 101a made of aluminum, and has a predetermined speed in the arrow direction. To rotate.

Reference numeral 102 denotes a charging roller which is a contact charging member which is brought into contact with the photosensitive drum 1 with a predetermined pressure, and a conductive rubber layer 102b is provided on a metal cored bar 102a.
Further, a surface layer 102c, which is a releasable coating, was provided on the peripheral surface. If the releasable coating has too much resistance, the photosensitive drum 1
If 01 is not charged and the resistance is too small, the photosensitive drum 1
01 is applied with too much voltage, and drum damage and pinholes occur.
It is preferably from ⁹ to 10 ¹⁴ Ωm, and the thickness of the releasing film at this time is preferably within 30 μm. Further, the lower limit of the thickness of the coating is considered to be preferably 5 μm, as long as the coating has no peeling and no stain.

As a specific example of the charging roller 102 usable in the present invention, the outer diameter is 12 mmφ, the conductive rubber layer 102b is EPDM, and the surface layer 102c is 10 mm thick.
A nylon resin having a thickness of μm is used, and the hardness of the charging roller 4 is 54.5 ° (ASKER-C). E is this Tiden roller 102
A predetermined voltage is applied to the charging roller 1 by a power supply unit that applies voltage to
No. 02 core metal 102a is supplied.

By using a conductive rubber layer for the charging roller, sufficient contact between the charging roller and the photosensitive member can be maintained and no charging failure will occur.

The charging roller having the above-mentioned structure, in which a releasing resin having a low surface energy such as nylon resin is used for the surface layer 102c as a releasing coating provided on the outer side of the conductive rubber layer 102b, is a photosensitive member. Since it is possible to prevent the softening agent from seeping out from the conductive rubber at the contact portion between the charging roller and the charging roller, image deletion due to the low resistance of the photoconductor caused by the adhesion of the softening agent to the photoconductor, and residual toner to the photoconductor In addition to being able to prevent a decrease in charging ability due to filming, a decrease in charging efficiency to be suppressed, and a decrease in toner releasability from a photoreceptor, a transfer having a specific shape factor used in the present invention can be suppressed. When combined with a toner that has high reproducibility and hardly causes retransfer, good transferability and retransfer prevention properties can be maintained, and a good full-color image can be formed.

In FIG. 5, E indicates a DC voltage, but it may be a DC voltage superposed with an AC voltage.

The charging roller 102 may be driven and rotated by the rotating photosensitive drum 101, or the photosensitive drum 10 may be rotated.
It may be rotationally driven in the same direction as the rotating direction of 1, or in the opposite direction, or may be non-rotating.

FIG. 6 is a schematic diagram of a charging blade as a contact charging member usable in the present invention. The same members as those of the apparatus of FIG. 5 are designated by the same reference numerals, and the repeated description will be omitted.

The contact charging member 103 is the photosensitive drum 101.
Is a blade-shaped member that is abutted in a forward direction with a predetermined pressure, and the blade 103 has a conductive rubber layer 103b supported by a metal supporting member 103a to which a voltage is supplied,
A surface layer 103c, which serves as a releasable coating, is provided at a portion in contact with the photosensitive drum 101. As the surface layer 103c, it is preferable to use a releasable resin such as a nylon resin having a thickness of 10 μm. According to this configuration, there is no problem such as adhesion between the blade and the photosensitive drum. Furthermore, the function and effect obtained by using the surface layer 103C of the releasing resin on the outer side of the conductive rubber layer 103b are the same as in the case of the charging roller described above.

As the contact charging member, a roller-shaped member and a blade-shaped member have been described, but the contact charging member is not limited to this, and other shapes can be used in the present invention.

In the above contact charging member, the one composed of the conductive rubber layer and the releasable coating film has been described. However, the contact charging member is not limited to this, and a leak to the photoconductor occurs between the conductive rubber layer and the surface layer of the releasable coating film. For prevention, it is preferable to form a high resistance layer, for example, a hydrin rubber layer having a small environmental change.

As the releasing resin, PVDF (polyvinylidene fluoride) or PVDC is used instead of the nylon resin.
(Polyvinylidene chloride) may be used. Amorphous silicon, selenium, or ZnO can also be used as the photoconductor. In particular, when amorphous silicon is used for the photoconductor, compared to the case where other materials are used, even if a small amount of the softening agent for the conductive rubber layer adheres to the photoconductor, the image deletion becomes worse. The effect of the insulating coating on the outside is great.

FIG. 7 is a schematic diagram of a magnetic brush as a contact charging member usable in the present invention.

The magnetic brush charger 104 is composed of a non-magnetic sleeve 106, a magnet roll 105 contained in the sleeve 106, and conductive magnetic particles 107 magnetically restrained on the sleeve 106.

As the conductive magnetic particles, various single or mixed crystal materials of conductive metals such as ferrite and magnetite can be used. The resistance is adjusted by reducing or oxidizing the once-sintered conductive magnetic particles. As the configuration of the conductive magnetic particles, fine particles having conductivity and magnetism are kneaded with a binder polymer, particles having conductive and magnetic particles obtained by molding into particles are dispersed in the binder polymer, The conductive magnetic particles may be further coated with a resin. At this time, the resistance of the coated resin layer is adjusted by adjusting the content of a conductive agent such as carbon to adjust the resistance of the entire conductive magnetic particles.

In the present invention, the conductive magnetic particles having an average particle diameter of 1 to 100 μm can be used.
Preferably, the particles having a thickness of 5 to 50 μm are excellent in terms of achieving both chargeability and retention of particles.

In the present invention, the average particle size of the conductive magnetic particles is randomly extracted by an optical microscope or a scanning electron microscope, and 100 or more particles are extracted at random, and the volume particle size distribution is calculated with the maximum chord length in the horizontal direction. Determined by particle size.

The magnetic brush charger 104 is the photosensitive drum 11
The distance between the sleeve 106 and the drum surface is 0.1 to 1 m
The end portion in the longitudinal direction is fixed via a spacer member (not shown) so that the length becomes m, and the magnetic brush of the conductive magnetic particles 107 is brought into contact with the surface of the photoconductor drum.
The photosensitive drum is electrically charged by rotating the sleeve 106 in the same direction as the drum 110 (clockwise in FIG. 7) while fixing 05.

To charge the photoconductor using the magnetic brush charger 104, the photoconductor has a charge injection layer,
It is preferable to directly inject charges from the magnetic brush into this charge injection layer.

The preferred structure of the photosensitive drum for charging using this magnetic brush charger will be described in detail below.

The photosensitive drum 110 is an aluminum base 1.
11 is an organic photoconductor coated with an undercoat layer, a positive charge injection prevention layer, a charge generation layer, and a charge transport layer in this order (OP
C) It has a structure in which a charge injection layer 113 is further applied on the layer 112. The charge injection layer 113 is preferably a resin such as a photo-curable acrylic resin in which conductive particles are dispersed in an amount of 20 to 100 parts by weight based on 100 parts by weight of the resin. As the conductive fine particles, materials such as SnO ₂ , TiO ₂ and ITO can be used. The average particle diameter of the conductive fine particles is preferably 1 μm or less, more preferably 0.5 to 5
The range of 0 nm is preferable for uniform charging.

The average particle size of the conductive fine particles in the present invention is 100 or more randomly extracted by a scanning electron microscope, the volume particle size distribution is calculated with the maximum chord length in the horizontal direction, and the average particle size is calculated with 50% of the average particle size. The diameter.

As the resin binding the conductive fine particles, it is possible to use a transparent resin material such as acrylic resin, polycarbonate, polyester, polyethylene terephthalate and polystyrene. In addition, in order to improve the slipperiness of the surface of the photosensitive drum, a slippery material such as Teflon is added to the charge injection layer 113 in an amount of 10 to 4 with respect to 100 parts by weight of the binder resin.
It is also possible to add 0 part by weight. Crosslinking agent for film formation,
It is also possible to add an appropriate amount of a polymerization initiator. Charge injection layer 1
Reference numeral 13 is a charge injection layer 113 in which charge sites are intentionally produced by directly injecting charges from the magnetic brush charger 104 so as to uniformly charge the surface. The resistance value of 1 must be 1 × 10 ⁸ Ωcm or more.

In the present invention, the resistance value of the charge injection layer 113 is obtained by coating a charge injection layer on an insulating sheet and measuring the surface resistance with a high resistance meter 4329A manufactured by Hewlett-Packard Company at an applied voltage of 100V. is there.

At the time of charging the photoconductor using the magnetic brush charger 104, a desired voltage is applied to the sleeve 106 to inject charges into the charge injection layer 113, and the surface of the photoconductor drum 110 finally becomes a magnetic brush. It is charged (charged) to the same potential.

Next, the structure of the developing device usable in the present invention will be described in detail with reference to the drawings.

In the present invention, a contact developing system in which a developer carried by a developer carrying member is brought into contact with the surface of the photosensitive member in the developing region for development, and a developer carrying member is carried on the surface of the photosensitive member in the developing region. It is possible to use any of the non-contact jumping development methods in which the developing agent is caused to fly from the developer carrying member set at a distance such that the photosensitive member and the developer layer are not in contact with each other for development.

Examples of the contact developing method include a developing method using a two-component developer having a toner and a carrier and a developing method using a one-component developer. In the case of the contact developing method, the developing device as the developing means can also serve as the cleaning means for cleaning and removing the toner existing on the photoconductor after the transfer, so that it exists on the surface of the photoconductor after the transfer. It is not necessary to separately provide a cleaning means such as a cleaning blade for removing toner, which is preferable in terms of simplification and compactness of the apparatus.

As the contact two-component developing method, a two-component developing agent in which toner and magnetic carrier are mixed is used, for example, as shown in FIG.
Development can be performed using the developing device 120 as shown in FIG.

The developing device 120 comprises a two-component developer 128.
And a developing sleeve 121 as a developer carrier for carrying the two-component developer 128 housed in the developing container 126 and carrying it to the developing area.
It has a developing blade 127 as a developer layer thickness regulating means for regulating the layer thickness of the toner layer formed on the developing sleeve 121.

The developing sleeve 121 includes a magnet 123 in a non-magnetic sleeve base 122.

The inside of the developing container 126 is partitioned by a partition wall 130 into a developing chamber (first chamber) R ₁ and a stirring chamber (second chamber) R _2, and toner is stored above the stirring chamber R _{2 with} the partition wall 130 in between. A chamber R ₃ is formed. The developer 128 is contained in the developing chamber R ₁ and the stirring chamber R ₂ , and the toner storage chamber R ₃
Replenishment toner (non-magnetic toner) 129 is contained therein. A replenishment port 131 is provided in the toner storage chamber R _3, and a replenishment toner 129 in an amount commensurate with the toner consumed through the replenishment port 131 is dropped and replenished into the stirring chamber R ₂ .

[0219] A conveying screw 124 in the developing chamber R ₁ provided, the developer 128 in the developing chamber R ₁ by the driving rotation of the conveying screw 124 is conveyed toward the longitudinal direction of the developing sleeve 121 . Similarly, a conveying screw 125 is provided in the storage chamber R ₂ , and the toner dropped from the replenishing port 131 into the stirring chamber R ₂ is conveyed along the longitudinal direction of the developing sleeve 121 by the rotation of the conveying screw 125.

The developer 128 is a two-component developer containing a non-magnetic toner and a magnetic carrier.

An opening is provided at a portion of the developing container 126 close to the photosensitive drum 119, and the developing sleeve 121 projects to the outside through the opening, and a gap is provided between the developing sleeve 121 and the photosensitive drum 119. ing. Bias applying means 132 for applying a bias is disposed on the developing sleeve 121 formed of a non-magnetic material.

As described above, the magnet roller fixed to the sleeve base 122 as the magnetic field generating means, that is, the magnet 123, carries the developing magnetic pole S ₁ , the magnetic pole N ₃ located downstream thereof, and the developer 128. Magnetic poles N ₂ , S ₂ ,
With N ₁ . The magnet 123 is arranged in the sleeve base 122 so that the developing magnetic pole S ₁ faces the photosensitive drum 119. The developing magnetic pole S ₁ forms a magnetic field in the vicinity of the developing section between the developing sleeve 121 and the photosensitive drum 119,
A magnetic brush is formed by the magnetic field.

The regulating blade 127 arranged above the developing sleeve 121 and regulating the layer thickness of the developer 128 on the developing sleeve 121 is made of a non-magnetic material such as aluminum or SUS316. The distance A between the end of the non-magnetic blade 127 and the surface of the developing sleeve 121 is 300 to 10
The thickness is 00 μm, preferably 400 to 900 μm. If this distance is less than 300 μm, the magnetic carrier is clogged between them and unevenness is likely to occur in the developer layer, and the developer necessary for good development cannot be applied, resulting in a thin developed image with a large unevenness. There is a problem that you can only get it. In order to prevent uneven coating (so-called blade clogging) due to unnecessary particles mixed in the developer,
It is preferably 400 μm or more. If it is larger than 1000 μm, the amount of the developer applied onto the developing sleeve 121 increases and the predetermined developer layer thickness cannot be regulated, so that the adhesion of magnetic carrier particles to the photosensitive drum 119 increases and the developer circulates or does not flow. There is a problem that the regulation of development by the magnetic developing blade 127 is weakened, toner tribo is insufficient, and fogging easily occurs.

In the development of the two-component developing device 120, an alternating electric field is applied and the toner and the magnetic carrier are used.
It is preferable that the development is performed in a state of being in contact with the magnetic brush latent image carrier (for example, the photoconductor drum) 119 that is configured. The distance (SD distance) B between the developer bearing member (developing sleeve) 121 and the photosensitive drum 119 is 100 to 100.
A thickness of 0 μm is good for preventing carrier adhesion and improving dot reproducibility. If it is less than 100 μm, the supply of the developer tends to be insufficient and the image density becomes low,
If it exceeds 1000 μm, the magnetic lines of force from the magnet S1 spread and the density of the magnetic brush becomes low, resulting in poor dot reproducibility, weakening of the carrier restraining force, and easy carrier adhesion.

The voltage between the peaks of the alternating electric field is 500 to 50.
00V is preferable, the frequency is 500 to 10000 Hz,
The frequency is preferably 500 to 3000 Hz, and can be appropriately selected and used for each process. In this case, the waveform may be triangular wave, rectangular wave, sine wave, or duty.
It is possible to select and use a waveform with a different ratio. When the applied voltage is lower than 500 V, it is difficult to obtain a sufficient image density, and it may be impossible to satisfactorily collect the fog toner in the non-image area. If it exceeds 50,000 V, the electrostatic image may be disturbed via the magnetic brush, which may lead to deterioration in image quality.

By using a two-component type developer having a well-charged toner, the fog removing voltage (Vback)
Can be lowered, and the primary charging of the photoconductor can be reduced, so that the life of the photoconductor can be extended. Vbac
The value k depends on the developing system, but is preferably 150 V or less, more preferably 100 V or less.

The contrast potential is preferably 200 V to 500 V so that a sufficient image density can be obtained.

When the frequency is lower than 500 Hz, although it is related to the process speed, charge injection into carriers may occur, which may deteriorate the image quality due to carrier adhesion or disturbing the latent image. If it exceeds 10000 Hz, the toner cannot follow the electric field and the image quality is likely to deteriorate.

The contact width (developing nip C) of the magnetic brush on the developing sleeve 121 with the photosensitive drum 119 is preferably in order to obtain sufficient image density, excellent dot reproducibility, and development without carrier adhesion. It is to be 3 to 8 mm. If the developing nip C is narrower than 3 mm, it is difficult to satisfactorily satisfy the sufficient image density and dot reproducibility. It becomes difficult to hold down enough. As a method of adjusting the developing nip, the nip width is appropriately adjusted by adjusting the distance A between the developer regulating member 127 and the developing sleeve 121 or by adjusting the distance B between the developing sleeve 121 and the photosensitive drum 119.

As the contact one-component developing method, it is possible to use both a magnetic toner and a non-magnetic toner. For example, a developing device 140 as shown in FIG. 9 can be used for development. Is.

The developing device 140 includes a developing container 1 for containing a one-component developer 148 having magnetic or non-magnetic toner.
41, one-component developer 1 contained in the developing container 141
A developer carrying member 142 for carrying 48 and carrying it to the developing area, a supply roller 145 for supplying the developer onto the developer carrying member, and a developer layer thickness on the developer carrying member for regulating the developer layer thickness. Elastic blade 14 as a developer layer thickness regulating member
6. It has a stirring member 147 for stirring the developer 149 in the developing container 141.

As the developer carrying member 142, it is preferable to use an elastic roller having an elastic layer 144 formed by an elastic member such as rubber or resin having elasticity such as foamed silicone rubber on the roller base 143.

The elastic roller 142 is brought into pressure contact with the surface of the photosensitive drum 139 serving as a latent image holding member, and electrostatically formed on the photosensitive member by the one-component developer 148 applied to the surface of the elastic roller. While developing the latent image, unnecessary one-component developer 148 existing on the photoconductor after transfer is collected.

In the present invention, the developer carrying member is substantially in contact with the surface of the photosensitive member. This means that the developer carrier is in contact with the photoconductor when the one-component developer is removed from the developer carrier. At this time, an image having no edge effect is obtained by the electric field acting between the photoconductor and the developer carrying member through the developer, and at the same time, cleaning is performed. It is necessary that the surface of the elastic roller as a developer carrying member or the vicinity thereof has an electric potential and an electric field between the surface of the photosensitive member and the surface of the elastic roller. For this reason,
It is also possible to use a method in which the elastic rubber of the elastic roller is resistance-controlled in the medium resistance region to prevent electric conduction with the surface of the photoconductor and maintain an electric field, or a thin dielectric layer is provided on the surface layer of the conductive roller. Further, there is also a configuration in which a conductive resin sleeve having a surface contacting with the surface of the photosensitive member coated with an insulating material on the conductive roller or a conductive layer provided on the surface of the insulating sleeve not contacting the photosensitive member is provided. It is possible.

The elastic roller carrying the one-component developer may rotate in the same direction as the photosensitive drum or may rotate in the opposite direction. When the rotation is in the same direction, the photosensitive roller may be rotated. A peripheral speed ratio with respect to the peripheral speed of the body drum is preferably greater than 100%. When it is 100% or less, a problem is likely to occur in image quality such as poor line sharpness.
The higher the peripheral speed ratio, the greater the amount of developer supplied to the development site, the more frequent the desorption of the developer with respect to the electrostatic latent image, and the unnecessary portion of the developer is scraped off. By repeatedly applying the developer to the portion, an image faithful to the electrostatic latent image can be obtained. More preferably, the peripheral speed ratio is 110% or more. From the perspective of simultaneous cleaning during development, it is also expected that the transfer residual developer adhering to the photoconductor will be physically peeled off by the peripheral speed difference between the photoconductor surface and the part where the developer is attached, and recovered by the electric field. Therefore, the higher the peripheral speed ratio of the elastic roller to the photosensitive drum is, the better the recovery of the transfer residual developer is.

The developer layer thickness regulating member 146 is not limited to the elastic blade as long as it is pressed against the surface of the developer carrying member 142 by elastic force, and an elastic roller can be used.

As the elastic blade and elastic roller, a rubber elastic body such as silicone rubber, urethane rubber or NBR; a synthetic resin elastic body such as polyethylene terephthalate; a metal elastic body such as stainless steel or steel can be used. Further, even a complex thereof can be used.

In the case of an elastic blade, the base which is the upper side of the elastic blade is fixedly held on the developer container side, and the lower side is bent in the forward or reverse direction of the developing sleeve against the elasticity of the blade. In this state, the inner surface of the blade (or the outer surface in the opposite direction) is brought into contact with the sleeve surface with appropriate elastic pressing.

The supply roller 145 is made of a foam material such as polyurethane foam, rotates in a forward or reverse direction relative to the developer carrying member at a non-zero relative speed, and supplies the one-component developer together with the developer. The developer after development (undeveloped developer) on the carrier is also stripped off.

In the developing area, when the electrostatic latent image on the photoconductor is developed by the one-component developer on the developer carrying member,
It is preferable to apply a DC and / or AC developing bias between the developer carrying member and the photoconductor drum for development.

Next, the non-contact jumping developing system will be described.

Examples of the non-contact jumping developing method include a developing method using a one-component magnetic developer having a magnetic toner and a developing method using a one-component non-magnetic developer having a non-magnetic toner.

A developing method using a one-component magnetic developer having a magnetic toner will be described with reference to the schematic configuration diagram shown in FIG.

The developing device 150 includes a developing container 151 containing a one-component magnetic developer 155 having a magnetic toner, and a one-component magnetic developer 15 contained in the developing container 151.
5, a developer carrier 1 for carrying 5 and carrying it to the developing area.
52, a doctor blade 154 as a developer layer thickness regulating member for regulating the developer layer thickness on the developer carrier, and a stirring member 156 for stirring the one-component magnetic developer 155 in the developing container 151. are doing.

In FIG. 10, the substantially right half peripheral surface of the developing sleeve 152 as a developer carrying member is always in contact with the developer pool in the developer container 151, and the magnetic one-component type developer near the developing sleeve surface. Are adhered and held to the surface of the developing sleeve by the magnetic force of the magnetic generation means 153 in the sleeve and / or by the electrostatic force. When the developing sleeve 152 is rotated, the developer layer on the sleeve surface is removed by the doctor blade 154.
In the process of passing through the position (1), each layer is layered as a thin layer T ₁ of the magnetic one-component developer having a substantially uniform thickness. The magnetic one-component developer is charged mainly by frictional contact between the sleeve surface accompanying the rotation of the developing sleeve 152 and the magnetic one-component developer in the developer pool in the vicinity thereof. The thin layer surface of the component-based developer rotates toward the latent image holding member 149 as the developing sleeve rotates,
9 and the developing sleeve portion 152 which is the closest portion to the developing area portion D.
Pass through. In the course of this passage, a thin magnetic one-component developer of the magnetic one-component developer on the surface of the developing sleeve 152 is applied between the latent image carrier 149 and the developing sleeve 152. And fly back and forth between the surface of the latent image carrier 149 in the developing area D and the surface of the developing sleeve 152 (gap α). Finally, the magnetic one-component developer on the developing sleeve 152 side is the electrostatic latent image holding member 1.
The developer image T ₂ is sequentially formed on the surface 49 and the surface thereof by selectively transferring and adhering in accordance with the potential pattern of the electrostatic latent image.

The developing sleeve surface on which the magnetic one-component type developer has been selectively consumed after passing through the developing area D is the developing container 9
By re-rotating to the developer reservoir of No. 1, the magnetic one-component developer is re-supplied, and the developing sleeve 15 is moved to the developing area D.
The surface of the thin layer T ₁ of the magnetic one-component developer of _{No. 2} is transferred and the developing process is repeated.

The doctor blade as the developer image layer thickness regulating member used in the present invention is a metal blade or a magnetic blade (for example, 154 shown in FIG. 10) arranged with a certain gap from the developing sleeve. .

Instead of the doctor blade as the developer layer thickness regulating member, a rigid roller or sleeve made of metal, resin or ceramic may be used, and a magnetism generating means may be provided inside.

In a one-component developing method such as a magnetic one-component developing method and a non-magnetic one-component developing method, an elastic blade which comes into elastic contact with the developing sleeve surface is used as a developer layer thickness regulating member. An elastic roller may be used as the developer layer thickness regulating member instead of the doctor blade.

As the elastic blade and elastic roller, a rubber elastic body such as silicone rubber, urethane rubber, NBR; a synthetic resin elastic body such as polyethylene terephthalate; a metal elastic body such as stainless steel and steel can be used. Even a complex can be used. Preferably,
Rubber elastic body is good.

The material of the elastic blade and the elastic roller has a great influence on the charging of the developer on the developer carrier. Therefore, an organic substance or an inorganic substance may be added, melt-mixed, or dispersed in the elastic body. Examples thereof include metal oxides, metal powders, ceramics, carbon allotropes, whiskers, inorganic fibers, dyes, pigments and surfactants. Further, rubber, synthetic resin, or metal elastic body may be used in which a substance such as resin, rubber, metal oxide, or metal is attached to the sleep contact portion so as to control the chargeability of the toner. When durability is required for the elastic body and the developer carrying body, it is preferable to bond the metal elastic body with resin or rubber so as to contact the sleeve contact portion.

When the developer is negatively charged, urethane rubber, urethane resin, polyamide, nylon or a positively chargeable developer is preferable. When the developer is positively charged, urethane rubber, urethane resin, silicone rubber, silicone resin, polyester resin, fluorine resin (for example, Teflon resin), polyimide resin, or a material which is easily negatively charged is preferable. When the developing sleep contact portion is a molded body such as resin or rubber, a metal oxide such as silica, alumina, titania, tin oxide, zirconia or zinc oxide is used in the molded body to adjust the charging property of the developer. ,
It is also preferable to include carbon black, a charge control agent generally used in toners.

FIG. 11 shows a doctor blade 154 as a developer layer thickness regulating member used in the developing device 150 of FIG.
Is fixed to the developing container 151 at one end and the other end at the developer carrying member 1.
A schematic configuration diagram of a developing device 160 in which a blade 157 that is pressed against an elastic member 52 by pressure is used is shown.

11, the same components as those in FIG. 10 are designated by the same reference numerals.

The elastic blade 157 as a developer layer thickness regulating member has a base portion, which is an upper side portion, fixedly held on the developer container 151 side, and a lower side portion in the order of the developing sleeve 152 against the elasticity of the elastic blade. Elastic blade inner surface side (in the opposite direction, outer surface side) by flexing in the opposite direction
Is brought into contact with the surface of the developing sleeve with an appropriate elastic pressure. According to such a device, a thin and dense toner layer can be obtained more stably against environmental changes. Although the reason is not always clear, the developer is forcibly rubbed against the surface of the developing sleeve 152 by the elastic blade 157 as compared with a device in which a commonly used metal blade is mounted at a certain distance from the developing sleeve. Therefore, it is presumed that the charging is always performed in the same state regardless of the behavior change due to the environmental change of the developer.

On the other hand, it is easy to be excessively charged and the toner on the developing sleeve and the blade is easily fused. However, the toner of the present invention has excellent fluidity, and therefore it is preferably used.

In the case of the magnetic one-component developing method, the contact pressure between the elastic blade and the developing sleeve is 0.1 kg / m or more, preferably 0.3 in terms of the linear pressure in the developing sleeve generatrix direction.
-25 kg / m, more preferably 0.5-12 kg / m
Is valid. If the contact pressure is less than 0.1 kg / m, it becomes difficult to apply the developer uniformly, and the developer is spread due to the distribution of the charge amount of the developer, which causes fog and scattering. When the contact pressure exceeds 25 kg / m, a large pressure is applied to the developer and the developer is deteriorated, which may cause aggregation of the developer, which is not preferable. Further, a large torque is required to drive the developer carrier, which is not preferable.

In the present invention, the gap α between the latent image holding member and the developer carrying member is set to, for example, 50 to 500 μm. When a magnetic blade is used as the developer layer thickness regulating member, the magnetic blade and the developing member are used. The gap with the agent carrier is 50
It is preferably set to 400 μm.

The layer thickness of the magnetic one-component developer on the developer carrier is most preferably thinner than the gap α between the latent image carrier and the developer carrier, but in some cases, the magnetic one-component developer is used. The layer thickness of the magnetic one-component type developer may be regulated so that a part of a large number of magnetic one-component type developer constituting the agent layer contacts the electrostatic latent image holding member.

The developing sleeve is 100 times larger than the latent image carrier.
It is rotated at a peripheral speed of ~ 200%. The alternating bias voltage is
Peak-to-peak is 0.1 kV or more, preferably 0.
It is preferable to use at 2 to 3.0 kV, and more preferably 0.3 to 2.0 kV. The alternating bias frequency is 1.0 to 5.
It is used at 0 kHz, preferably 1.0 to 3.0 kHz, and more preferably 1.5 to 3.0 kHz. A waveform such as a rectangular wave, a sine wave, a sawtooth wave, or a triangular wave can be applied to the alternating bias waveform. Furthermore, asymmetrical AC bias with different positive and reverse voltages and different time can be used. It is also preferable to superimpose a DC bias.

In the present invention, the developing sleeve is made of a material such as metal or ceramics, but aluminum and SUS are preferable from the viewpoint of charging the developer. The developing sleeve can be used as it is pulled out or cut, but in order to control the developer transporting property and the triboelectric charging property, polishing, roughening in the circumferential direction or longitudinal direction, and blasting treatment are performed. It is applied and coated. In the present invention, a blast treatment may be performed, and the regular particles and the irregular particles are used as the blasting agent, and they may be used alone or in combination, and may be overlaid.

Any abrasive grains can be used as the irregular particles.

As the regular particles, for example, various hard spheres or ceramics made of metal such as stainless steel, aluminum, steel, nickel and brass having a specific particle diameter,
Various hard spheres such as plastic and glass beads can be used. The regular particles have a substantially curved surface and have a major axis / minor axis ratio of 1 to 2 (preferably 1).
~ 1.5, more preferably 1-1.2) spherical or spheroidal particles are preferred. Therefore, the fixed particles used for the blast treatment on the surface of the developing sleeve preferably have a diameter (or major axis) of 20 to 250 μm. In the case of repeated hitting, the size of the regular blast particles is preferably larger than that of the irregular blast particles, particularly preferably 1 to 20 times, more preferably 1.5 to 9 times.

[0264] When performing the over-strike treatment with the regular particles, it is preferable that at least one of the treatment time and the collision force of the treated particles be smaller than that of the irregular particle blast.

As a developing sleeve, on the sleeve surface,
Those having a coating layer containing conductive fine particles are also preferable. The conductive fine particles are preferably carbon fine particles, carbon fine particles and crystalline graphite, or crystalline graphite.

The crystalline graphite used in the present invention is roughly classified into natural graphite and artificial graphite. Artificial graphite is made by solidifying pitch coke with tar pitch, firing it once at about 1,200 ° C, and then putting it in a graphitization furnace.
By treating at a high temperature of about 2,300 ° C., carbon crystals grow and change into graphite. Natural graphite is completely graphitized from the ground by natural geothermal heat and underground high pressure for a long time. These graphites are dark gray or black luster and are very soft and slippery crystalline minerals. They are used for pencils and have heat resistance and chemical stability, so they are suitable for lubricants, fire resistant materials, electrical materials, etc. It is used in the form of powder, solid and paint. The crystal structure includes 60,000 crystals and others belonging to the rhombohedral system, and has a completely layered structure. Regarding the electrical characteristics, free electrons are present between carbon-carbon bonds, making it a good conductor of electricity. The graphite used in the present invention may be natural or artificial.

The graphite used in the present invention has a grain size of 0.
It is preferably 5 μm to 20 μm.

The polymer material forming the coating layer is, for example,
Styrene resin, vinyl resin, polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, fiber resin,
Thermoplastic resin such as acrylic resin; use of thermosetting resin or photocurable resin such as epoxy resin, polyester resin, alkyd resin, phenol resin, melamine resin, polyurethane resin, urea resin, silicone resin, polyimide resin You can Among them, those having releasability such as silicone resin and fluororesin, or those having excellent mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol resin, polyester, polyurethane and styrene resin are more preferable. .

Conductive amorphous carbon is generally defined as "an aggregate of crystallites formed by burning or pyrolyzing a hydrocarbon or a compound containing carbon in a state where the supply of air is insufficient". . In particular, it is widely used because it has excellent electric conductivity, and it can be filled with a polymer material to give conductivity, or it can obtain an arbitrary conductivity to some extent by controlling the amount added. The particle diameter of the conductive amorphous carbon used in the present invention is preferably 10 nm to 80 nm, more preferably 15 nm to 40 nm.

Next, a developing method using a one-component non-magnetic developer having a non-magnetic toner will be described with reference to the schematic configuration diagram shown in FIG.

The developing device 170 includes a developing container 17 containing a non-magnetic one-component developer 176 having a non-magnetic toner.
1. A developer carrier 172 for carrying the one-component non-magnetic developer 176 contained in the developing container 171 and transporting it to the developing area, and supplying the one-component non-magnetic developer onto the developer carrier. For stirring the supply roller 173, the elastic blade 174 as a developer layer thickness regulating member for regulating the developer layer thickness on the developer carrier, and the one-component non-magnetic developer 176 in the developing container 171. It has a stirring member 175.

Reference numeral 169 is an electrostatic latent image holder, and the latent image is formed by electrophotographic process means or electrostatic recording means (not shown). Reference numeral 172 denotes a developing sleeve as a developer carrying member, which is a non-magnetic sleeve made of aluminum or stainless.

As the developing sleeve, a rough tube made of aluminum or stainless steel may be used as it is, but it is preferable that the surface thereof is uniformly roughened by spraying glass beads.
A mirror-finished one or a resin-coated one is preferable, and it conforms to the one used in the non-contact one-component magnetic developing method used in FIG.

The one-component non-magnetic developer 176 is used in the developing container 1.
It is stored in 71 and is supplied onto the developer carrier 172 by the supply roller 173. Supply roller 173
Is made of a foam material such as polyurethane foam,
The developer is rotated in a forward or reverse direction at a relative speed that is not 0 with respect to the developer carrying member, and the developer is supplied and the developer (undeveloped developer) after development on the developer carrying member 172 is stripped off. There is. The one-component non-magnetic developer supplied onto the developer carrier 172 is uniformly and thinly applied by the elastic blade 174 as a developer layer thickness regulating member.

The contact pressure between the elastic coating blade and the developer carrying member is 0.3 to 25 as the linear pressure in the developing sleeve generatrix direction.
kg / m, preferably 0.5 to 12 kg / m is effective. If the contact pressure is less than 0.3 kg / m, it becomes difficult to uniformly apply the one-component non-magnetic developer, and the charge distribution of the one-component non-magnetic developer becomes broad, causing fog and scattering. When the contact pressure exceeds 25 kg / m, a large pressure is applied to the one-component non-magnetic developer, and the one-component non-magnetic developer is deteriorated, so that aggregation of the one-component non-magnetic developer occurs, which is preferable. Absent. A large torque is required to drive the developer carrier, which is not preferable. That is, by adjusting the contact pressure to 0.3 to 25 kg / m, it becomes possible to effectively loosen the agglomeration of the one-component non-magnetic developer using the toner of the present invention. It is possible to instantly raise the charge amount of the non-magnetic developer.

The developer layer thickness regulating member is based on that used in the non-contact one-component magnetic developing method used in FIG.
For the elastic blade and elastic roller, it is preferable to use a material of triboelectrification series suitable for charging the developer to a desired polarity, and the one used in the non-contact one-component magnetic developing method used in FIG. According to In the present invention, silicone rubber, urethane rubber, and styrene-butadiene rubber are suitable. Further, an organic resin layer such as polyamide, polyimide, nylon, melamine, melamine cross-linked nylon, phenol resin, fluorine resin, silicone resin, polyester resin, urethane resin, styrene resin may be provided. A conductive rubber or conductive resin is used, and a filler or charge such as metal oxide, carbon black, inorganic whiskers, or inorganic fibers is used in accordance with the one used in the non-contact one-component magnetic development method used in FIG. It is preferable to disperse the control agent in the rubber of the blade or the resin so as to impart appropriate conductivity and charge imparting property and to appropriately charge the one-component non-magnetic developer.

In this non-magnetic component developing method, in a system in which a thin layer of a one-component non-magnetic developer is coated on the developing sleeve by a blade, in order to obtain a sufficient image density, the one-component non-magnetic developer on the developing sleeve is not used. It is preferable to make the thickness of the magnetic developer layer smaller than the opposing gap length β between the developing sleeve and the latent image carrier, and apply an alternating electric field to this gap.
That is, by applying a developing bias in which a DC electric field is superimposed on the alternating electric field or the alternating electric field between the developing sleeve 172 and the latent image holding member 169 by the bias power source shown in FIG. It is possible to facilitate the transfer of the one-component non-magnetic developer to the toner, and to obtain a high quality image. These conditions are also in accordance with the non-contact one-component non-magnetic developing method used in FIG.

[0278]

EXAMPLES The present invention will be described in more detail with reference to specific methods for producing toner and photosensitive drums, examples, and comparative examples.

(Cyan Toner Production Example 1) 450 g of 0.1 M Na ₃ PO ₄ aqueous solution was added to 710 g of ion-exchanged water, and the mixture was heated to 60 ° C. and then TK type homomixer (made by Tokushu Kika Kogyo). Was stirred at 12000 rpm. 68 g of 1.0 M-CaCl ₂ aqueous solution was gradually added to this to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

On the other hand, (monomer) styrene 170 g n-butyl acrylate 40 g (colorant) C.I. I. Pigment Blue 15: 3 15g- (Charge control agent) Metal salicylate compound 3g- (Polar resin) Saturated polyester 10g

The above formulation was heated to 60 ° C., and 12,000 rpm was obtained using a TK homomixer (made by Tokushu Kika Kogyo).
Were uniformly dissolved and dispersed. In addition to this, the polymerization initiator 2,
2'-azobis (2,4-dimethylvaleronitrile) 1
0 g was dissolved to prepare a polymerizable monomer composition.

The above polymerizable monomer composition was put into the above aqueous medium and stirred at 60 ° C. under N ₂ atmosphere with a TK type homomixer at 10,000 rpm for 10 minutes to give the polymerizable monomer composition. Granulated. Then, while stirring with a paddle stirring blade, the temperature was raised to 80 ° C. and the reaction was performed for 10 hours. After the completion of the polymerization reaction, the residual monomer was distilled off under reduced pressure for 3 hours,
After cooling, add hydrochloric acid to dissolve the calcium phosphate,
After filtering, washing with water and drying, the weight average particle size is about 7.5μ.
m, sharp cyan suspension particles (toner particles) 1 having a coefficient of variation in particle size distribution of 27% were obtained. The content of residual monomer in the obtained toner particles 1 was 140 ppm.

Hydrophobicity of the obtained toner particles 1 treated with a silane coupling agent and dimethyl silicone oil is 95% with respect to 98.5 parts by weight, and the average particle size is 15 nm. 1.5 wt% of silica A was externally added to obtain a suspension-polymerized cyan toner A. 95 parts by weight of an acrylic-coated ferrite carrier was mixed with 5 parts by weight of this toner to prepare a two-component developer.

The toner shape factor was measured to find that SF-
It was 1 = 110 and SF-2 = 108.

(Production Example 2 of cyan toner) In Production Example 1 of cyan toner, except that the distillation of the monomer after completion of the polymerization reaction is carried out under reduced pressure for 30 minutes,
Cyan suspension particles (toner particles) having a residual monomer content of 2000 ppm in the same manner as in Cyan Toner Production Example 1.
2 was prepared, and hydrophobic silica A was externally added in the same manner to prepare suspension-polymerized cyan toner 2, which was mixed with a carrier to obtain a two-component developer.

Production Example 3 of Cyan Toner In Production Example 1 of cyan toner, 98.5 toner particles 1 after classification are used.
Except for externally adding 1.5 parts by weight of hydrophobic silica B having a hydrophobicity of 87% treated with a silane coupling agent and an average particle diameter of 20 nm, based on parts by weight,
Similarly, a suspension-polymerized cyan toner 3 was prepared and mixed with a carrier to obtain a two-component developer.

(Production Example 4 of cyan toner) In Production Example 1 of cyan toner, 98.5 toner particles 1 after classification are used.
With the exception of adding externally 1.5 parts by weight of treated silica C having a hydrophobicity of 55% surface-treated with dimethyldichlorosilane and an average particle size of 16 nm, based on parts by weight. A suspension-polymerized cyan toner 4 was prepared and mixed with a carrier to obtain a two-component developer.

(Production Example 5 of cyan toner) In Production Example 1 of cyan toner, 98.0 toner particles 1 after classification are used.
A hydrophobic silica A surface-treated with 1.0 part by weight of hydrophobic silica A, a silane coupling agent and dimethyl silicone oil has a hydrophobicity of 94% and an average particle size of 70% by weight.
A suspension-polymerized cyan toner 5 was prepared and mixed with a carrier in the same manner except that 1.0 part by weight of hydrophobic silica D having a particle size of 1.0 nm was externally added, and a two-component developer was obtained.

(Production Example 6 of cyan toner) In Production Example 1 of cyan toner, 98.0 toner particles 1 after classification are used.
1.0 part by weight of hydrophobic silica E having a hydrophobicity of 91% surface-treated with a silane coupling agent and an average particle diameter of 100 nm, and hydrophobically treated with a silane coupling agent, relative to parts by weight. A suspension-polymerized cyan toner 6 was prepared in the same manner except that 1.0 part by weight of hydrophobic silica F having a degree of conversion of 90% and an average particle size of 110 nm was externally added, and was used as a carrier. A two-component developer was obtained by mixing.

(Production Example 7 of cyan toner) In Production Example 1 of cyan toner, 98.0 toner particles 1 after classification are used.
1.0 part by weight of hydrophobic silica A and 1.0 part by weight of hydrophobic silica G having a degree of hydrophobicity of 90% surface-treated with a silane coupling agent and an average particle size of 140 nm, based on parts by weight. A suspension-polymerized cyan toner 7 was prepared in the same manner except that it was externally added and mixed with a carrier to obtain a two-component developer.

(Production Example 8 of cyan toner) In Production Example 1 of cyan toner, 98.0 toner particles 1 after classification are used.
1.0 part by weight of hydrophobic silica A surface-treated with a silane coupling agent and having a hydrophobicity of 93% and an average particle diameter of 26 nm, relative to 1.0 part by weight. A suspension-polymerized cyan toner 8 was prepared in the same manner except that it was externally added, and was mixed with a carrier to obtain a two-component developer.

(Production Example 9 of cyan toner) In Production Example 1 of cyan toner, 98% by weight of toner particles 1 after classification, 1.0 part by weight of treated silica C and 1. Suspension-polymerized cyan toner 9 was prepared in the same manner except that 0 part by weight of external addition was added, and mixed with a carrier to obtain a two-component developer.

(Cyan Toner Production Example 10) 180 parts by weight of water purged with nitrogen and 20 parts by weight of a 0.20 wt% aqueous solution of polyvinyl alcohol were charged into a four-necked flask, followed by 77 parts by weight of styrene and acrylic acid-n. -Butyl 22
By weight, 1.4 parts by weight of benzoyl peroxide and 0.2 part by weight of divinylbenzene were added and stirred to give a suspension. Then, the inside of the flask was replaced with nitrogen, and then the temperature was raised to 80 ° C. and the temperature was maintained for 10 hours to carry out a polymerization reaction.

After washing the polymer with water, it was dried in a reduced pressure environment while maintaining the temperature at 65 ° C. to obtain a resin. 88 the resin
wt%, 2 wt% metal-containing azo dye, C.I. I. Pigment Blue 15:35 5 wt% and low-molecular-weight polypropylene 3 wt% were mixed by a fixed-tank type dry mixer, and the melt was kneaded by a twin-screw extruder while suctioning by connecting a vent port to a suction pump.

The melt-kneaded product was crushed with a hammer mill to obtain a crushed product of the toner composition having a 1 mm mesh pass.
Furthermore, this coarsely crushed product is subjected to a volume average diameter of 2 by a mechanical crusher.
After pulverizing to 0 to 30 μm, pulverizing with a jet mill utilizing collision between particles in a swirling flow, and modifying the toner composition by thermal and mechanical shearing force in a surface reformer. Then, classification was carried out by a multistage classifier to obtain cyan toner particles 10 having an average particle size of 7.9 μm and a coefficient of variation in particle size distribution of 32%.

98.5 wt% of the cyan toner particles 10
% Of hydrophobic silica A was externally added to obtain pulverized cyan toner 10. 95 parts by weight of an acrylic-coated ferrite carrier was mixed with 5 parts by weight of this toner to prepare a two-component developer.

When the toner shape factor was measured, SF-
1 = 175 and SF-2 = 136.

(Cyan Toner Production Example 11) Into a four-necked flask were charged 180 parts by weight of nitrogen-substituted water and 20 parts by weight of a 0.2 wt% aqueous solution of polyvinyl alcohol, and then 77 parts by weight of styrene and acrylic acid-n were added. -Butyl 22
By weight, benzoyl peroxide (1.5 parts by weight) and divinylbenzene (0.3 parts by weight) were added and stirred to give a suspension. Then, after replacing the inside of the flask with nitrogen,
The temperature was raised to 10 ° C. and the temperature was maintained for 10 hours to carry out a polymerization reaction. The polymer was washed with water and dried under reduced pressure while maintaining the temperature at 65 ° C to obtain a resin.

88% by weight of the resin and 2% of metal-containing azo dye
wt%, C.I. I. Pigment Blue 15:37 wt%,
3 wt% of low molecular weight polypropylene was mixed by a fixed tank dry mixer and melt-kneaded by a twin-screw extruder.

The melt-kneaded product was crushed with a hammer mill to obtain a crushed product of the toner composition having a 1 mm mesh pass.
Further, this coarsely pulverized product was finely pulverized using an air pulverizer equipped with a collision plate. The finely pulverized product was classified by a multistage classifier to obtain cyan toner particles 11 having an average particle size of 7.5 μm and a variation coefficient of 28% in the particle size distribution. The content of the residual monomer in the obtained toner particles 11 is 300.
It was ppm.

Hydrophobic silica A was externally added to this cyan toner 11 in the same manner as in Production Example 10 of cyan toner to prepare a crushed cyan toner 11, which was mixed with a carrier to obtain a two-component developer.

The toner shape factor was measured to find that SF-
1 = 191 and SF-2 = 161.

(Production Example 12 of cyan toner) In Production Example 1 of cyan toner, a spheroidizing treatment was carried out by a thermal and mechanical shearing force in a surface modifier before classifying the cyan toner particles 11. The particles were classified by a classifier to obtain cyan toner particles 12 having a weight average particle diameter of 7.4 μm. Hydrophobic silica A was externally added to the cyan toner particles 12 in the same manner as in Cyan Toner Production Example 10 to prepare ground cyan toner 12 and mixed with a carrier to obtain a two-component developer.

When the toner shape factor was measured, SF-
It was 1 = 170 and SF-2 = 130.

Cyan Toner Production Example 13 A four-necked flask was charged with 180 parts by weight of nitrogen-substituted water and 20 parts by weight of a 0.2 wt% aqueous solution of polyvinyl alcohol, and then 77 parts by weight of styrene and acrylic acid were added. n-butyl 22
By weight, benzoyl peroxide (1.5 parts by weight) and divinylbenzene (0.3 parts by weight) were added and stirred to give a suspension. Then, after replacing the inside of the flask with nitrogen,
The temperature was raised to 10 ° C. and the temperature was maintained for 10 hours to carry out a polymerization reaction.

After washing the polymer with water, it was dried in a reduced pressure environment while maintaining the temperature at 65 ° C. to obtain a resin. 50 of the resin
wt%, 1 wt% metal-containing azo dye, C.I. I. Pigment Blue 15:35 5 wt% and low-molecular-weight polypropylene 1 wt% were mixed by a fixed tank type mixer, and melt-kneading was performed by a twin-screw extruder while suctioning by connecting a vent port to a suction pump.

The melt-kneaded product was crushed with a hammer mill to obtain a crushed product of the toner composition having a 1 mm mesh pass.
Further, this coarsely crushed product was subjected to a mechanical crusher to obtain a volume average diameter of 2
After crushing to 0 to 30 μm, crushing is performed with a jet mill that utilizes collision between particles in a swirling flow, and classification is performed using a multi-stage classifier, and the average particle size is 7.0 μm. 38% of cyan toner particles 13 were obtained. The content of residual monomer in the obtained toner particles 13 was 200 ppm.

Hydrophobic silica A was externally added to this cyan toner 13 in the same manner as in Production Example 10 of cyan toner to prepare a pulverized cyan toner 13, which was mixed with a carrier to obtain a two-component developer.

When the toner shape factor was measured, SF-
It was 1 = 171 and SF-2 = 160.

(Production Example 14 of cyan toner) In Production Example 10 of cyan toner, except that the classification conditions were changed, the weight average diameter was about 7.9 μm and the variation coefficient in particle size distribution was 38%. Cyan suspension particles (toner particles) 14 were prepared in the same manner as above, and hydrophobic silica A was externally added in the same manner to prepare suspension polymerization toner 14, which was mixed with a carrier to obtain a two-component developer.

Production Example 15 of Cyan Toner In Production Example 10 of cyan toner, the resin was dried at a temperature of 45 ° C.
Cyan toner particles 15 having a residual monomer content of 1800 ppm are prepared in the same manner, except that the drying is performed under normal pressure in the same manner.
Was externally added to prepare a cyan toner 15, which was mixed with a carrier to obtain a two-component developer.

Table 1 shows the constitution and physical properties of the obtained cyan toner 1-15.

[0313]

[Table 1]

(Production Example 1-15 of Magenta Toner) C.I. I. Pigment Blue 15: 3 is C.I. I. Magenta Toner 1-15 was prepared in the same manner except that Pigment Red 122 was used to obtain a two-component developer.

(Production Example 1-15 of Yellow Toner) C.I. I. Pigment Blue 15: 3 is C.I. I. Pigment Yellow 17, except that Yellow Toner 1-15 was prepared in the same manner to obtain a two-component developer.

(Production Example 1-15 of Black Toner) C.I. I. Pigment Blue 15: 3 was replaced with furnace carbon black, and Black Toner 1-15 was prepared in the same manner to obtain a two-component developer.

(Production Example 16 of Black Toner)-(Monomer) Styrene 165 g n-Butyl acrylate 35 g- (Coloring agent) Carbon black 15 g- (Charge controlling agent) Salicylic acid metal compound 5 g- (Polar resin) Saturated polyester 10 g

The above formulation was heated to 60 ° C. and uniformly dissolved and dispersed at 12000 rpm using a TK homomixer (made by Tokushu Kika Kogyo). In addition to this, the polymerization initiator 2,2 '
-Azobis (2,4-dimethylvaleronitrile) 10g
Was dissolved to prepare a polymerizable monomer composition.

The above polymerizable monomer composition was charged into the aqueous medium of Production Example 1, and the mixture was added to a TK homomixer at 10000 rpm at 20 ° C. in an N ₂ atmosphere at 60 ° C.
After stirring for a minute, the polymerizable monomer composition was granulated. afterwards,
While stirring with a paddle stirring blade, the temperature was raised to 80 ° C. and the reaction was performed for 10 hours. After completion of the polymerization reaction, residual monomers were distilled off under reduced pressure and distillation time under the same conditions as in Production Example 1, and after cooling, hydrochloric acid was added to dissolve calcium phosphate, followed by filtration, washing with water and drying, and weight average Sharp black suspended particles (toner particles) 16 having a diameter of about 7.2 μm and a coefficient of variation in particle size distribution of 28% were obtained. The content of the residual monomer in the obtained toner particles 16 was 110 ppm.

Hydrophobic silica A was externally added to this black toner 16 in the same manner as in Production Example 1 for cyan toner to prepare a suspension-polymerized black toner 16, which was mixed with a carrier to obtain a two-component developer. It was

The toner shape factor was measured and found to be SF-
It was 1 = 112 and SF-2 = 110.

(Cyan Toner Production Example 21-35) Cyan Toner 21-35 was prepared in the same manner as in Cyan Toner Production Example 1-15 except that the amounts of the external additives were changed as shown in Table 2. Each prepared cyan toner was used as a one-component developer.

[0323]

[Table 2]

(Production of Magenta Toner 21-35) Production of magenta toner except that the amount of the external additive in the production 1-15 of magenta toner was changed in the same manner as the cyan toner 21-35 shown in Table 2. Magenta toners 21-35 were prepared in the same manner as 1-15, and the obtained magenta toners were used as a one-component developer.

(Production of yellow toner 21-35) Production of yellow toner except that the amount of the external additive in the production 1-15 of yellow toner was changed in the same manner as the cyan toner 21-35 shown in Table 2. Yellow toners 21-35 were prepared in the same manner as 1-15, and the obtained yellow toners were used as a one-component developer.

(Production of Black Toner 21-35) Production of Black Toner except that the amount of the external additive in Production 1-15 of Black Toner was changed in the same manner as the cyan toner 21-35 shown in Table 2. Black toners 21-35 were prepared in the same manner as 1-15, and the obtained black toners were used as a one-component developer.

(Brackner Production Example 36) 180 parts by weight of nitrogen-substituted water and 20 parts by weight of a 0.2 wt% aqueous solution of polyvinyl alcohol were placed in a four-necked flask, and then 77 parts by weight of styrene and acrylic acid were added. n-butyl 22
By weight, 1.2 parts by weight of benzoyl peroxide and 0.2 part by weight of divinylbenzene were added and stirred to obtain a suspension. Then, after replacing the inside of the flask with nitrogen,
The temperature was raised to 10 ° C. and the temperature was maintained for 10 hours to carry out a polymerization reaction. The polymer was washed with water and dried under reduced pressure while maintaining the temperature at 65 ° C to obtain a resin.

55 wt% of the resin, 40 wt% of the magnetic substance of 0.1 μm, 1 wt% of the metal-containing azo dye, 3 wt% of carbon black, and 1 wt% of low molecular weight polypropylene were mixed by a fixed tank type dry mixer, and biaxially extruded. Melt kneading was performed in a machine.

The melt-kneaded product was crushed with a hammer mill to obtain a crushed product of the toner composition having a 1 mm mesh pass.
Further, this coarsely crushed product was subjected to a mechanical crusher to obtain a volume average diameter of 2
After pulverizing to 0 to 30 μm, the coarsely pulverized product is finely pulverized using an air pulverizer equipped with a collision plate, and the toner composition is subjected to thermal and mechanical shearing forces in a surface reformer. After being modified, black toner particles 36 having an average particle diameter of 6.8 μm and a coefficient of variation of 31% were obtained by performing classification with a multistage classifier. The residual monomer content of the obtained toner particles 36 was 180 ppm.

To 98 parts by weight of this black toner 17, hydrophobic silica A was prepared in the same manner as in Production Example 12 for cyan toner.
Was added externally to prepare a pulverized black toner 36, and the black toner 36 was used as a one-component development.

The toner shape factor was measured to find that SF-
It was 1 = 148 and SF-2 = 135.

(Production Example A of Photosensitive Drum) 10 parts by weight of conductive titanium oxide (tin oxide coat, average primary particle size 0.4 μm), 10 parts by weight of phenol resin precursor (resole type), 10 parts by weight of methanol, and butanol. After dispersing 10 parts by weight in a sand mill, dip coating on an aluminum cylinder and curing at 140 ° C., then volume resistance 5 × 10
A conductive layer having a thickness of ⁹ Ωcm and a thickness of 20 μm was provided.

Next, 10 parts by weight of the following methoxymethylated nylon (the degree of methoxymethylation is about 30%)

[0334]

[Outside 5] And 150 parts by weight of isopropanol were mixed and dissolved, and then dip-coated on the conductive layer to form an undercoat layer of 1 μm.

Next, 10 parts by weight of the following azo pigments

[0336]

[Outside 6] 5 parts by weight of the following polycarbonate resin (bisphenol A molecular weight 30,000)

[0337]

[Outside 7] And 700 parts by weight of cyclohexanone are dispersed by a sand mill, and the dispersion is dip-coated on the undercoat layer,
A charge generation layer having a thickness of 0.05 μm was obtained.

Next, 3 parts by weight of the following triphenylamine

[0339]

[Outside 8] 7 parts by weight of the following triphenylamine

[0340]

[Outside 9] 10 parts by weight of a polycarbonate resin having the following structure (bisphenol Z type, molecular weight 20000)

[0341]

[Outside 10] 50 parts by weight of monochlorobenzene and 15 parts by weight of dichloromethane were stirred and mixed, and then dip-coated on the charge generation layer. 20μ after drying the coated cylinder with hot air
m charge transport layer.

Next, 3 parts by weight of carbon fluoride fine powder (average particle size 0.27 μm, manufactured by Central Glass Co., Ltd.) 5.
5 parts by weight of the following polycarbonate resin (bisphenol Z molecular weight 80,000)

[0343]

[Outside 11] 0.3 parts by weight of the following fluorine-substituted graft polymer (F content 24% by weight, molecular weight 25000)

[0344]

[Outside 12] 120 parts by weight of monochlorobenzene and 80 parts by weight of dichloromethane were dispersed and mixed in a sand mill. to this,
2.5 parts by weight of the following triphenylamine

[0345]

[Outside 13] Then, the coating solution obtained by mixing and dissolving was applied onto the charge transport layer by spray coating to form a protective layer of 4 μm to obtain a photosensitive drum A.

After peeling off the surface of the photoreceptor, E produced by VG
The surface elements were quantified using an SCALAB200-X type X-ray photoelectron spectrometer. MgKα (300 as X-ray source
W) was used to measure a region of 2 × 3 mm at a depth of several angstroms. F existing on the surface of this photoconductor
Atoms are 11.3%, C atoms are 75.5%,
F / C was 0.150.

(Manufacturing Example B of Photosensitive Drum) In the photosensitive drum A of Manufacturing Example A, a photosensitive drum B was manufactured by replacing the protective layer with the following formulation.

1 part by weight of spherical three-dimensional crosslinked polysiloxane fine particles (average particle size 0.29 μm, manufactured by Toshiba Silicone Co., Ltd.), 6 parts by weight of the following polycarbonate resin (bisphenol Z molecular weight 80,000)

[0349]

[Outside 14] 0.1 parts by weight of the following polydimethylsiloxane methacrylate-methyl methacrylate block copolymer (molecular weight: 50,000, Si content: 12% by weight)

[0350]

[Outside 15] 120 parts by weight of monochlorobenzene and 80 parts by weight of dichloromethane were dispersed and mixed in a sand mill, and 3 parts by weight of the following triphenylamine was mixed.

[0351]

[Outside 16] Is added, mixed and dissolved, and is applied to the photosensitive drum A by spray coating.
Coating was performed on the charge transport layer used in the production of to prepare a photosensitive layer B having a protective layer of 3 μm. Si atoms existing on the surface of this photoconductor were 10.2% and C atoms were 69.3.
%, And the Si / C ratio was 0.147.

(Photosensitive Drum Manufacturing Example C) The photosensitive drum C of Manufacturing Example A prepared by coating the charge transport layer without providing a protective layer was used as a photosensitive drum C.

F atoms / Si existing on the surface of this photoreceptor
No atom was detected, and both the F / C ratio and the Si / C ratio were 0.

(Photosensitive Drum Manufacturing Example D) The photosensitive drum D was manufactured in the same manner as in the photosensitive drum A of Manufacturing Example A, except that the protective layer formed on the charge transport layer was formed as follows. Prepared.

30 parts by weight of the following acrylic monomers,

[0356]

[Outside 17]

50 parts by weight of tin oxide ultrafine particles (average particle size before dispersion 400Å), 20 parts by weight of polytetrafluoroethylene resin particles (average particle size 0.18 μm), and 18 parts by weight of a photopolymerization initiator 2-Methylthioxanthone and 150 parts by weight of ethanol were dispersed in a sand mill for 66 hours to prepare a coating liquid, which was coated on the charge transport layer by a dip coating method, and then 800
Photocuring was performed at a light intensity of w / cm ² for 60 seconds, and then dried with hot air at 120 ° C. for 2 hours to form a protective layer having a thickness of 3 μm.

The number of F atoms existing on the surface of this photoreceptor is 1
It was 1.5%, C atom was 74.8%, and F / C ratio was 0.154.

(Photosensitive Drum Manufacturing Example E) A photosensitive drum E was manufactured in the same manner as in the photosensitive drum B of Manufacturing Example B except that the protective layer formed on the charge transport layer was formed as follows. Prepared.

30 parts by weight of the following acrylic monomers,

[0361]

[Outside 18]

50 parts by weight of tin oxide ultrafine particles (average particle size before dispersion 400Å), 20 parts by weight of spherical three-dimensional polysiloxane fine particles (average particle size 0.29 μm), 18 parts by weight of photopolymerization start 2-Methylthioxanthone as an agent and 150 parts by weight of ethanol are dispersed in a sand mill for 66 hours to prepare a coating solution, which is applied on the charge transport layer by a dip coating method to obtain a high pressure mercury lamp. 800
Photocuring was performed at a light intensity of w / cm ² for 60 seconds, and then dried with hot air at 120 ° C. for 2 hours to form a protective layer having a thickness of 3 μm.

Si atoms present on the surface of this photoreceptor were 9.98%, C atoms were 70.1%, and Si /
The C ratio was 0.142.

(Photoreceptor Production Example F) In the photoconductor drum D of Production Example D, the polytetrafluoroethylene copolymer was not added to the coating liquid for forming the protective layer formed on the charge transport layer. Except for the above, a coating liquid was prepared in the same manner and a protective layer was formed in the same manner to obtain a photoconductor drum F.

F atoms existing on the surface of the obtained photoreceptor /
No Si atom was detected, and both F / C ratio and Si / C ratio were 0.
Met.

Example 1-15 and Comparative Example 1-2 As an image forming apparatus, two image forming units shown in FIG. 4 were arranged in this order in an apparatus having the structure shown in FIG.

In each image forming unit, a photosensitive drum having a diameter of 30 mm was used, and as a cleaning means, a urethane blade was brought into contact with the photosensitive drum to remove toner existing on the photosensitive member after transfer. Use a structure that collects with a cleaner, use a corona charger as a charging unit, and use a transfer blade as a transfer unit so that the transfer belt is brought into contact with the back surface of the transfer belt as a transfer material carrier and transferred under the following transfer conditions. An image portion was exposed using a semiconductor laser as an image forming means, and reversal development was performed using a two-component system contact developing device shown in FIG. 8 as a developing device.

The developing conditions are such that the distance A between the end surface of the non-magnetic blade and the surface of the developing sleeve is 500 μm, the distance B between the surface of the developing sleeve and the surface of the photosensitive drum is 500 μm, and the developing nip C is 6 mm. A square wave having a peak-to-peak voltage of 2000 V and a frequency of 2000 Hz was applied between the developing sleeve and the photosensitive drum to perform development.

As the transfer conditions, a magenta unit which is the first image forming unit is applied with a first transfer bias of a transfer current of 12 μA and a transfer voltage of +3.5 kV, and is transferred to a cyan unit which is the second image forming unit. Current 12
A second transfer bias of μA and transfer voltage +4.3 kV was applied.

The image forming speed is as follows: A4 size recording paper (length: about 297 mm x width: about 210 mm) is fed horizontally.
It was set to 15 sheets per minute.

A heat roller fixing machine was used as the fixing device.

The photosensitive drums A to C, the magenta toner 1-15 and the cyan toner 1-15 are provided in the magenta unit and the cyan unit of the above image forming apparatus, respectively.
The following combinations were used to form continuous images on 50,000 sheets in a high temperature / high humidity environment of 30 ° C./80% Rh, and the following evaluations were performed.

Image uniformity Image uniformity is an evaluation for observing a change in color tone due to a change in the transfer state of the transfer material at the second transfer portion before and after the transfer material has passed through the first transfer portion under a high temperature / high humidity environment. is there.

The distance between the transfer parts is 150 mm to 80 mm.
Image is formed under high temperature / high humidity environment with the setting gradually narrowed by 10 mm unit, and the change of color tone (change of color tone between the front area and the rear area in the transfer material conveyance direction) is visually observed on the initial image. The initial evaluation is the interval between the transfer parts as confirmed by. Furthermore, the interval between each transfer part is 1
Set 50mm, after continuous image formation of 50,000 sheets under high temperature / high humidity environment, the interval of each transfer part from 150mm to 80mm
Each image is formed with a setting of 10 mm in units of 10 mm, and a change in color tone (change in color tone between the front area and the rear area in the transport direction of the transfer material) is visually confirmed on each image. The interval between them is used as the evaluation after endurance.

Transfer Efficiency Transfer efficiency was evaluated in the high humidity / high temperature environment at the initial stage and after endurance of continuous image formation of 50,000 sheets. A magenta toner image (image density 1.4) formed on the photosensitive drum in the magenta unit is sampled with a transparent adhesive tape, and the image density (D ₁ ) is measured with a Macbeth densitometer or a color reflection densitometer (for example, Colorreflecti).
on densitometer X-RITE 40
4Amanufactured by X-Rite
Co. ). Next, a magenta toner image is formed again on the photosensitive drum, the magenta toner image is transferred to a recording material, and the magenta toner image transferred on the recording material is sampled with a transparent adhesive tape, and the image density (D ₂ ) Is similarly measured. The image density (D ₁ ) and (D ₂ ) thus obtained are calculated as follows.

Transfer efficiency (%) = (D ₂ / D ₁ ) × 100

Retransfer Rate The initial stage was evaluated under a high temperature / high humidity environment. A magenta toner image (image density 1.4) is transferred onto a recording material in a magenta unit, the transferred magenta toner image is collected with a transparent adhesive tape, and the image density (D ₃ ) is measured by a Macbeth densitometer or a color Measure with a reflection densitometer. Next, the magenta toner image is again transferred onto the recording material by the magenta unit, and then a solid white image (a cyan toner image is not formed on the photosensitive drum) is formed by the cyan unit,
This solid white image is transferred onto the recording material on which the magenta image has been transferred (only the transfer operation is performed because the cyan toner image is not actually formed), and the magenta toner image on the transfer material after the transfer. Is sampled with a transparent adhesive tape and the image density (D ₄ ) is measured. Obtained image density (D
_{It is} calculated from ₃ ) and (D ₄ ) as follows.

Retransfer rate (%) = [(D ₃ −D ₄ ) / D ₃ ] × 100

Waste toner box life 100c in magenta unit under high temperature / high humidity environment
The number of sheets until the toner collected in the waste toner box as the cleaner of c is fully distributed and replaced is counted.

The evaluation results are shown in Table 3.

[0380]

[Table 3]

Embodiments 16 and 17 Except that three image forming units are arranged in the order of magenta unit, cyan unit and yellow unit in the image forming apparatus used in Embodiment 1-15, and the transfer conditions are as follows. Then, a full-color image was formed in the same manner.

As a transfer condition, a first transfer bias having a transfer current of 12 μA and a transfer voltage of 3.5 kV is applied to the magenta unit which is the first image forming unit, and the transfer is performed to the cyan unit which is the second image forming unit. Current 12μ
A, a second transfer voltage having a transfer voltage of 4.3 kV was applied, and a third transfer bias having a transfer current of 12 μA and a transfer voltage of 5.1 kV was applied to the yellow unit which is the third image forming unit.

As the toner of the two-component developer, a combination of magenta toner 1, cyan toner 1 and yellow toner 1 (Example 16) and a combination of magenta toner 5, cyan toner 5 and yellow toner 5 (Example) 17), and using the photoconductor drum A as the photoconductor drum in a high temperature / high humidity environment, the distance between the transfer parts is set to 80 mm, and 50
When 000 sheets of continuous images were formed, it was possible to form a good full-color image without any change in the color tone being confirmed on the image after the endurance.

Example 18 and 19 Four image forming units were arranged in the image forming apparatus used in Examples 1-15 in the order of magenta unit, cyan unit, yellow unit and black unit, and the transfer conditions were as follows. A full-color image was formed in the same manner except that.

As a transfer condition, a first transfer bias having a transfer current of 12 μA and a transfer voltage of 3.5 kV is applied to the magenta unit which is the first image forming unit, and the transfer is performed to the cyan unit which is the second image forming unit. Current 12μ
A, a second transfer voltage having a transfer voltage of 4.3 kV is applied, and a third transfer bias having a transfer current of 12 μA and a transfer voltage of 5.1 kV is applied to the yellow unit, which is the third image forming unit, to obtain a fourth image. A fourth transfer bias having a transfer current of 12 μA and a transfer voltage of 5.9 kV was applied to the black unit as a forming unit.

As the toner of the two-component developer, a combination of magenta toner 1, cyan toner 1, yellow toner 1 and black toner 1 (Example 18), magenta toner 5, cyan toner 5, yellow toner 5 and black toner was used. 5 (Example 19), using the photoconductor drum A as the photoconductor drum in a high temperature / high humidity environment,
When the distance between the transfer portions was set to 80 mm and continuous image formation was performed on 50,000 sheets, no change in color tone was confirmed on the image until after the durability test, and a good full-color image could be formed.

Further, when images were formed in a room temperature / normal humidity environment of 23 ° C./60% Rh, good full-color images were obtained after 50,000 sheets of running.

The transfer conditions at that time are as follows: a magenta unit which is a first image forming unit, a first transfer bias of a transfer current of 15 μA and a transfer voltage of 4 kV is applied to a cyan unit which is a second image forming unit. Transfer current 15
A second transfer bias of μA and a transfer voltage of 4.9 kV is applied, and a third transfer bias of transfer current of 15 μA and a transfer voltage of 5.8 kV is applied to the yellow unit, which is the third image forming unit. Transfer current 15μA, transfer voltage 6.6
A fourth transfer bias of kV was applied.

Example 20 In Examples 18 and 19, transfer was performed in each image forming unit under the following transfer conditions by using a non-contact transfer unit including a corona charger as the image forming unit transfer unit. As in Nos. 19 and 19, good images were obtained. However, Examples 18 and 19 were superior in that the amount of ozone generated could be controlled.

As a transfer condition, a first transfer bias having a transfer current of 50 μA and a transfer voltage of 7.2 kV is applied to the magenta unit which is the first image forming unit, and the transfer is performed to the cyan unit which is the second image forming unit. Current 70μ
A, a second transfer bias having a transfer voltage of 7.2 kV is applied, and a third transfer bias having a transfer current of 90 μA and a transfer voltage of 7.2 kV is applied to the yellow unit, which is the third image forming unit, and the fourth transfer bias is applied. Transfer current 110μA, transfer voltage 7.2kV to the black unit which is an image forming unit
The fourth transfer bias was applied.

Example 21-35 and Comparative Example 3-4 In the image forming apparatus used in Examples 1-15 and Comparative Example 1-2, the charging means of each image forming unit was the conductive rubber layer shown in FIG. Example 1-Except that a charging roller whose surface is coated with a nylon-based resin is brought into contact with the surface of the photosensitive drum to change the contact charging device.
When evaluated in the same manner as in Example 15 and Comparative Example 1-2, similar results were obtained.

Working Examples 36 and 37 The charging means of each image forming unit used in Working Examples 16 and 17 is shown in FIG. 5, and a charging roller having a conductive rubber layer surface coated with a nylon resin is applied to the surface of the photosensitive drum. Image formation was carried out in the same manner as in Examples 16 and 17, except that a contact charger that charged by contact was used, and the same evaluation was carried out. Similar results were obtained. .

Working Examples 38 and 39 The charging means of each image forming unit used in Working Examples 18 and 19 is shown in FIG. 5, and a charging roller having the surface of the conductive rubber layer coated with a nylon resin is applied to the surface of the photosensitive drum. Image formation was carried out in the same manner as in Examples 18 and 19 except that a contact charger that charged by contact was used, and the same evaluation was carried out. The same results were obtained. .

Example 40 A full-color image was formed in the same manner as in Example 38 except that the black toner 16 was used in place of the black toner 1 used in Example 38. As a result, a good full-color image was formed in the same manner as in Example 38. Could be done.

Example 41-55 and Comparative Example 5-6 In the image forming apparatus used in Example 1-15 and Comparative example 1-2, the photosensitive drum of each image forming unit was replaced by the photosensitive drum A. In FIG. 7, the photoconductor drum B is changed to the photoconductor drum E, and the photoconductor drum C is changed to the photoconductor drum F. The charging means is a magnetic brush charger (contact type) in which a magnetic brush is formed on the conductive sleeve shown in FIG. Charger) is brought into contact with the surface of the photosensitive drum to directly inject the charge, and the toner existing on the surface of the photosensitive drum after transfer is removed by removing the cleaning means, except that the developing device collects the toner. In the same manner as in Example 1-15 and Comparative Example 1-2, 30,000 sheets of continuous images were formed, and the image uniformity, transfer efficiency and retransfer property were evaluated in the same manner.

Further, the charging characteristics and the image characteristics were evaluated by the following evaluation methods.

Charging Characteristic [0398] A DC voltage of -750V is applied to the conductive sleeve of the charger of the final image forming unit after the image formation durability, and what percentage of -750V the charging potential from 0V on the surface of the photoreceptor reaches. Was evaluated based on the following evaluation criteria.

A: 95% or more (excellent charging) B: 90% or more but less than 95% (good charging) C: Less than 90% (insufficient charging)

Image Characteristics Image characteristics were judged by white background fog, which shows the charged state of the photoconductor. The fogging is measured by a reflection densitometer (TOKYO
DENSHOKU CO. , LTD REFLEC
Measurement using TOMETER ODEL TC-6DS (solid white image is formed in each image forming unit after image output durability, and the solid white image is transferred and fixed on the transfer paper. Let Ds be the value and Ds be the reflection density average value of the transfer before image formation.
-Dr was used as the fog amount), and the evaluation was performed based on the following evaluation criteria.

A: 2% or less (substantially fog) B: More than 2% to 5% or less (some fog is present) C: More than 5% (fog is present)

Table 4 shows the evaluation results.

[0403]

[Table 4]

Embodiments 56 and 57 In the image forming apparatus used in Embodiments 16 and 17, the photosensitive drum of each image forming unit is changed to the photosensitive drum D, and the charging means is the magnetic brush charger (shown in FIG. 7). A contact charger is contacted with the surface of the photoconductor drum to directly inject the charge, and the cleaning means is removed to remove the toner present on the surface of the photoconductor drum after transfer by the developing device. Then, 30,000 sheets of continuous images were formed in the same manner as in Examples 16 and 17, and the image uniformity, transfer efficiency and retransfer property were evaluated in the same manner.

Further, regarding the charging characteristic and the image characteristic,
Evaluation was performed in the same manner as in Examples 41-55 and Comparative Examples 5-6.

As a result, Example 5 using a combination of magenta toner 1, cyan toner 1 and yellow toner 1
6 and magenta toner 5, cyan toner 5, yellow toner 5 and yellow toner 5 were used in combination in any of Examples 57, no change in color tone was confirmed on the image until after endurance, and a good full-color image was obtained. It was possible to form the film, and excellent results were obtained in both charging characteristics and image characteristics.

Embodiments 58 and 59 In the image forming apparatus used in Embodiments 18 and 19, the photosensitive drum of each image forming unit is changed to the photosensitive drum D, and the charging means is the magnetic brush charger (shown in FIG. 7). A contact charger is contacted with the surface of the photoconductor drum to directly inject the charge, and the cleaning means is removed to remove the toner present on the surface of the photoconductor drum after transfer by the developing device. Then, continuous image formation was performed on 30,000 sheets in the same manner as in Examples 18 and 19, and the image uniformity, transfer efficiency and retransfer property were evaluated in the same manner.

Regarding the charging characteristics and the image characteristics,
Evaluation was performed in the same manner as in Examples 41-55 and Comparative Examples 5-6.

As a result, the combination of Example 58 and the combination of magenta toner 5, cyan toner 5, cyan toner 5, yellow toner 5 and black toner 5 used in the combination of magenta toner 1, cyan toner 1, yellow toner 1 and black toner 1 was obtained. In each of Example 59 used, no change in color tone was confirmed on the image until after endurance, a good full-color image could be formed, and excellent charging characteristics and image characteristics were obtained. Was given.

Example 60 A full-color image was formed in the same manner as in Example 58, except that the black toner 16 was used in place of the black toner 1 used in Example 58. As a result, a good full-color image was formed in the same manner as in Example 58. Could be done.

Example 61-75 and Comparative Example 7-8 In the image forming apparatus used in Examples 1-15 and Comparative Example 1-2, the developing device of each image forming unit is a non-magnetic one-component system shown in FIG. Example 1-15 and Comparative Example 1-2, except that the magenta toner 21-35 and the cyan toner 21-35 shown in Table 2 are developed using the jumping developing device under the following developing conditions. When 7,000 sheets of continuous images were formed in the same manner and further evaluated, similar results were obtained.

The developing conditions are such that a urethane blade as a toner layer thickness regulating member is brought into pressure contact with the surface of the photosensitive drum, and the gap β between the surface of the photosensitive drum and the surface of the developing sleeve is 400.
μm, the thickness of the toner layer on the developing sleeve is set to 30 μm, and the peak-to-peak voltage of the alternating electric field is 16 as the developing bias.
A rectangular wave having a frequency of 00 V and a frequency of 1800 Hz was applied between the developing sleeve and the photosensitive drum, and the toner on the developing sleeve was scattered on the photosensitive drum for development.

Examples 76 and 77 In the image forming apparatus used in Examples 61-75 and Comparative Examples 7-8, three image forming units were arranged in this order, a magenta unit, a cyan unit and a yellow unit, and full color was obtained in the same manner. An image was formed.

As the one-component developer, a combination of magenta toner 21, cyan toner 21 and yellow toner 21 (Example 76) and a combination of magenta toner 25, cyan toner 25 and yellow toner 25 (Example 7) were used.
7), the photosensitive drum A was used as the photosensitive drum, and 7,000 sheets of continuous images were formed in a high temperature / high humidity environment with the distance between the transfer parts set to 80 mm. No change in color tone was confirmed, and a good full-color image was formed.

Examples 78 and 79 In the image forming apparatus used in Examples 61-75 and Comparative Examples 7-8, four image forming units were arranged in this order, a magenta unit, a cyan unit, a yellow unit and a black unit. And a full-color image was formed.

As the one-component developer, a combination of magenta toner 21, cyan toner 21, yellow toner 21 and black toner 21 (Example 78) and magenta toner 25, cyan toner 25, yellow toner 25 and black toner 25 are used. Used in the combination (Example 79) of
When the photosensitive drum A was used as the photosensitive drum in a high-temperature / high-humidity environment, and the distance between the transfer portions was set to 80 mm to continuously form 7,000 images, the color tone changed on the image after the endurance. It was possible to form a good full-color image without confirmation.

Further, when images were formed in a normal temperature / normal humidity environment of 23 ° C./60% Rh, good full-color images were obtained after 7,000 sheets of running.

The transfer conditions at that time are as follows: a magenta unit, which is the first image forming unit, is applied with a first transfer bias having a transfer current of 15 μA and a transfer voltage of 4 kV, and a cyan unit, which is the second image forming unit. Transfer current 15
A second transfer bias of μA and a transfer voltage of 4.9 kV is applied, and a third transfer bias of transfer current of 15 μA and a transfer voltage of 5.8 kV is applied to the yellow unit, which is the third image forming unit. Transfer current 15μA, transfer voltage 6.6
A fourth transfer bias of kV was applied.

Example 80 Of the four image forming units used in Example 78, only the developing unit of the black unit was changed to the magnetic one-component jumping developing device shown in FIG.
A cyan toner, a magenta toner, and a toner similar to those in Example 78 except that the development is performed under the following developing conditions.
A full color image was formed with four colors of yellow toner and black toner, and a good full color image was obtained.

The development conditions are as follows: a Cretan blade as a toner layer thickness regulating member is brought into pressure contact with the surface of the photosensitive drum, and a developing sleeve is a resin-coated sleeve having a magnet inside, and the surface of the photosensitive drum is The gap β from the sleeve surface is 300 μm 8 The layer thickness of the magnetic toner layer on the developing sleeve is set to 160 μm, and the voltage between the peaks of the alternating electric field is 1600 V and the frequency is 1 as the developing bias.
A rectangular wave of 800 Hz was applied between the developing sleeves and the photosensitive drums, and the magnetic toner on the developing sleeves was scattered on the photosensitive drums for development.

Examples 81-95 and Comparative Examples 9-10 In the image forming apparatus used in Examples 1-15 and Comparative Example 1-2, the charging means was nylon resin on the surface of the conductive rubber layer shown in FIG. The contact charging device that charges the coated charging roller by contacting the surface of the photosensitive drum is used, and the developing device is shown in Table 2 under the following developing conditions using the contact one-component developing device shown in FIG. Magenta toner 21-3
5 and cyan toners 21-35 are developed, the cleaning means is removed, and the toner present on the photoconductor after transfer is changed to be collected by this developing device. -15 and Comparative Example 1-2
The continuous image formation of 7,000 sheets was carried out in the same manner as in Example 1, and the image uniformity, transfer efficiency and retransfer property were evaluated in the same manner as in Example 1-15 and Comparative Example 1.
A result similar to that of -2 was obtained.

Further, the charging characteristics and the image characteristics were evaluated in the same manner as in Examples 41-55 and Comparative Example 5-6. As a result, Examples 41-55 and Comparative Example 5-
Results similar to those of No. 6 were obtained.

The developing device uses a medium resistance rubber roller made of foamed silicone rubber and having an electric resistance value of 5 × 10 ⁵ Ω · cm as a toner carrier, and brings this toner carrier into contact with the surface of the photosensitive drum. The rotation direction and the peripheral speed of the toner carrier were the same in the contact portion with the photosensitive drum, and the toner carrier was driven so as to be 200% of the rotational peripheral speed of the photosensitive member. As means for applying toner to the toner carrier, the application roller is brought into contact with the surface of the toner carrier, and the application roller is rotated in the opposite direction to the toner carrier at the contact portion with the toner carrier to carry the toner. The toner layer thickness was controlled by applying toner to the body and bringing a stainless steel blade as a toner layer thickness regulating member into contact with the toner layer. As the developing bias, −
The development was performed by applying only the DC component of 450 V, and the toner existing on the photosensitive drum was collected after the transfer.

Examples 96 and 97 Except that the image forming apparatus used in Examples 81-95 is arranged with three image forming units in the order of magenta unit, cyan unit and yellow unit, and the transfer conditions are as follows. Then, a full-color image was formed in the same manner.

As the toner of the one-component developer, magenta toner 21, cyan toner 21 and yellow toner 2 are used.
The combination of No. 1 (Example 96) and the combination of magenta toner 25, cyan toner 25, and yellow toner 25 (Example 97) is used as a photosensitive drum.
When a continuous image was formed on 7,000 sheets by setting the distance between transfer parts to 80 mm under high temperature / high humidity environment using
It was possible to form a good full-color image without any change in the color tone being confirmed on the image after the endurance.

Embodiments 98 and 99 Four image forming units are arranged in the image forming apparatus used in Embodiments 81-95 in the order of magenta unit, cyan unit, yellow unit and black unit, and the transfer conditions are as follows. A full-color image was formed in the same manner except that.

As the toner of the one-component developer, magenta toner 21, cyan toner 21, and yellow toner 21 are used.
And a combination of black toner 21 (Example 98) and a combination of magenta toner 25, cyan toner 25, yellow toner 25 and black toner 25 (Example 99).
And using the photoconductor drum A as the photoconductor drum in a high-temperature / high-humidity environment, setting the distance between the transfer parts to 80 mm.
When 000 sheets of continuous images were formed, it was possible to form a good full-color image without any change in the color tone being confirmed on the image after the endurance.

Example 100 A full-color image was formed in the same manner as in Example 98, except that the black toner 26 was used in place of the black toner 21 used in Example 98. Could be formed.

[0429]

In the present invention, at least the first image forming unit and the second image forming unit are contained,
The length of the transfer material in the transport direction is longer than the distance between the first transfer portion of the first image forming unit and the second transfer portion of the second image forming unit, and the first transfer bias is Second
In the image forming apparatus in which the transfer bias of
The toner forming the first toner image and the toner forming the second toner image each have SF-1 of 100 to 1
Since 80 and SF-2 have a shape factor of 100 to 140, the transfer efficiency is high, the occurrence of retransfer is suppressed, and the first transfer portion and the transfer material are kept under high temperature and high humidity. Forming a good full-color image with little influence on the transfer at the second transfer part before and after passing, excellent image uniformity, and with little change in color tone under normal temperature and normal humidity and high temperature and high humidity environments. Can be performed faster than before,
Further, the entire device can be made compact.

[Brief description of drawings]

FIG. 1 is a schematic view for explaining a first embodiment that can carry out an image forming method of the present invention.

FIG. 2 is a diagram showing a correlation between SF-1 and SF-2 and lubricity.

FIG. 3 is a diagram showing a correlation between transfer efficiency and shape coefficient.

FIG. 4 is a first enlarged view of a part of the image forming apparatus shown in FIG.
2 is a schematic explanatory diagram of the image forming unit of FIG.

FIG. 5 shows a schematic configuration diagram of a charging roller as a contact charging member.

FIG. 6 is a schematic configuration diagram of a charging blade as a contact charging member.

FIG. 7 is a schematic configuration diagram of a magnetic brush as a contact charging member.

FIG. 8 is a schematic configuration diagram of a developing device of a contact two-component developing system.

FIG. 9 is a schematic configuration diagram of a developing device of a contact one-component developing system.

FIG. 10 is a schematic configuration diagram of a non-contact one-component magnetic developing type developing device.

11 is a schematic configuration diagram of a developing device in which an elastic blade is used instead of the developer layer thickness regulating means of the developing device of FIG.

FIG. 12 is a schematic configuration diagram of a non-contact one-component system non-magnetic developing type developing device.

FIG. 13 is a schematic configuration diagram showing an example of a conventional image forming apparatus.

[Explanation of symbols]

 Pa, Pb, Pc, Pd Image forming unit 1a, 1b, 1c, 1d Photosensitive drums 2a, 2b, 2c, 2d Drum charger 3a, 3b, 3c, 3d Developing device 4a, 4b, 4c, 4d Transfer charger 5a, 5b, 5c, 5d Photoconductor cleaning section 6 Recording material 7 Fixing section 8 Recording material carrier 9 Transfer cleaning device 10 Belt drive roller 11 Belt driven roller 12 Belt static eliminator 13 Registration roller 14 Separation charger 15 Separation charger 16 Fur brush 17 Polygon Mirror 18 Separation Claws 21a, 21b, 21c, 21d Exposure Lamp 22a, 22b, 22c, 22d Potential Sensor 31a, 31b, 31c, 31d Photo Sensor 41a, 41b, 41c, 41d Transfer Pressing Member 60 Recording Paper Cassette 71 Fixing Roller 72 Pressure roller 73,74 Cleaning device 75,76 Heater 77 Oil application roller 78 Oil sump 79 Thermistor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location G03G 15/08 507 G03G 15/16 9/08 15/16 384

Claims (60)

[Claims] 1. A step of conveying a transfer material to a first image forming unit, a step of forming a first toner image by a first image forming means of the first image forming unit, and a first formed image. A step of applying a first transfer bias to the toner image and performing a first transfer on the transfer material at a first transfer portion of the first image forming unit; and forming a second image on the transfer material. A step of conveying to a unit, a step of forming a second toner image by the second image forming means of the second image forming unit,
A second transfer bias is applied to the formed second toner image, and the second transfer portion of the second image forming unit
The second toner is transferred onto the transfer material on which the first toner image is transferred.
And a step of performing the transfer of the first and the first transferred to the transfer material.
In the image forming method, including the step of fixing the toner image and the second toner image to the transfer material by a fixing unit, the transfer material of the transfer material is more than the distance between the first transfer portion and the second transfer portion. The first transfer bias and the second transfer bias are different from each other in length in the carrying direction, and the first toner and the second toner forming the first toner image are different from each other.
The second toner forming the toner image of
An image forming method, wherein -1 has a shape factor of 100 to 180 and SF-2 has a shape factor of 100 to 140. 2. The distance between the first transfer portion and the second transfer portion is 110 mm or less.
The image forming method described in 1 .. 3. The distance between the first transfer portion and the second transfer portion is 100 mm or less.
The image forming method described in 1 .. 4. The second transfer bias is set to be higher in a polarity opposite to a charging polarity of the second toner with reference to the first transfer bias. 4. The image forming method according to any one of 1 to 3. 5. The first toner and the second toner are
In each case, SF-1 is 100 to 160 and SF-2 is 10.
The image forming method according to claim 1, wherein the image forming method has a shape coefficient of 0 to 135. 6. The first toner and the second toner are
In each case, SF-1 is 100 to 140 and SF-2 is 10.
The image forming method according to claim 1, wherein the image forming method has a shape coefficient of 0 to 120. 7. The first toner and the second toner are
7. The image forming method according to claim 1, wherein the residual monore content is 1000 ppm or less. 8. The first toner and the second toner are
The image forming method according to any one of claims 1 to 6, wherein the residual monore content is 500 ppm or less. 9. The first toner and the second toner are
9. The toner according to claim 1, wherein each of the toner particles has a weight average particle diameter in the range of 1 to 9 μm and a variation coefficient (A) in the number distribution of 35% or less. Image forming method. 10. The first toner and the second toner each include a mixture of toner particles and fine powder having a hydrophobicity of 60% or more.
The image forming method according to any one of 1. 11. The first toner and the second toner each include a mixture of toner particles and fine powder having a hydrophobicity of 90% or more.
The image forming method according to any one of 1. 12. The first toner and the second toner each include toner particles, a hydrophobicized inorganic fine powder a, and a hydrophobicized silicon compound b having a particle size larger than that of the inorganic fine powder a. 2. A mixture according to claim 1.
10. The image forming method according to any one of 9 to 9. 13. The inorganic fine powder a has an average particle size of 3 to 90.
nm, and the silicon compound b has an average particle size of 30 to 120.
13. The image forming method according to claim 12, further comprising: 14. The image forming method according to claim 12, wherein the inorganic fine powder a has a hydrophobicity of 60% or more. 15. The image forming method according to claim 12, wherein the inorganic fine powder a has a hydrophobicity of 90% or more. 16. The first toner image has a first latent image holding member for holding a first electrostatic latent image in the first image forming unit, which is primaryly charged by a first charging unit. A step of charging, a step of forming a first electrostatic latent image on the first charged latent image holding member by a first latent image forming means, and a step of forming the first electrostatic latent image.
Is formed by a step of developing the electrostatic latent image of the second electrostatic latent image with the first toner held in the first developing means, and the second toner image is formed by the second static image in the second image forming means. The step of primary charging the second latent image holding member for holding the electrostatic latent image by the second charging means, and the second latent image holding member that is primary charged by the second latent image forming means. It is formed by a step of forming a second electrostatic latent image and a step of developing the second electrostatic latent image with the second toner held in a second developing means. Item 16. The image forming method according to any one of Items 1 to 15. 17. The first latent image carrier and the second latent image carrier are both measured by X-ray photoelectron spectroscopy (XPS) of fluorine atoms and carbon atoms present on the surface of the latent image carrier. The image forming method according to claim 16, wherein the abundance ratio (F / C) is within a range of 0.03 to 1.00. 18. The first latent image carrier and the second latent image carrier are both measured by X-ray photoelectron spectroscopy (XPS) of silicon atoms and carbon atoms present on the surface of the latent image carrier. The image forming method according to claim 16, wherein the abundance ratio (Si / C) is within a range of 0.03 to 1.00. 19. The first charging means is a non-contact charging means for charging the surface of the first latent image holding body in a non-contact manner, and the second charging means is the second latent image holding means. 19. The image forming method according to claim 16, which is a non-contact charging unit that charges the body surface in a non-contact manner. 20. The first charging unit is a contact charging unit that contacts and charges the surface of the first latent image carrier, and the second charging unit is the second latent image carrier. 17. A contact charging means for charging by contacting a surface.
19. The image forming method according to any one of 18 to 18. 21. The first image forming device and the second image forming device are both carried on the developer carrying member in the developing area rather than on the space between the latent image holding member and the developer carrying member. The developer has a larger layer thickness, and has a contact development system in which the layer of the developer on the developer carrying member is brought into contact with the surface of the latent image holding member to develop with the toner of the developer. 21. The image forming method according to claim 16, further comprising: 22. The image forming method according to claim 21, wherein the developer is a two-component developer having a toner and a magnetic carrier. 23. The image forming method according to claim 21, wherein the developer is a one-component developer containing toner. 24. The first image forming unit and the second image forming unit are both cleaning for removing toner existing on the surface of the latent image holding member after transfer between the transfer unit and the charging unit. 24. The method according to claim 21, wherein the developing means does not have any means, and also has a function as a cleaning means for collecting and cleaning the toner existing on the surface of the latent image holding body after the transfer. The image forming method described. 25. The first image forming unit and the second image forming unit are both carried on the developer carrying member in the developing area rather than the space between the latent image holding member and the developer carrying member. The layer thickness of the developed developer is smaller, and the layer of the developer on the developer carrier is not in contact with the surface of the latent image carrier from the developer carrier to the surface of the latent image carrier. 21. The image forming method according to claim 16, further comprising a non-contact developing method of flying and developing with the toner of the developer. 26. The image forming method according to claim 25, wherein the developer is a one-component developer containing toner. 27. The image forming method further comprises a step of transporting the transfer material to a third image forming unit before fixing after the second transfer is performed by the second image forming unit, A step of forming a third toner image by the third image forming means of the third image forming unit, applying a third transfer bias to the formed third toner image to form the third image. A step of performing a third transfer on the transfer material onto which the first toner image and the second toner image have been transferred at a third transfer portion of the unit, and the step of transferring the transfer material onto the transfer material. A step of fixing the first toner image, the second toner image, and the third toner image onto the transfer material by the fixing means, and the second transfer portion and the third transfer portion. The length of the transfer material in the conveying direction is longer than the distance, and the first transfer bias and the second transfer bias A transfer bias of the transfer bias and the third are both are different from a third toner to form a toner image of said third SF-
27 has a shape factor of 100 to 180 and SF-2 of 100 to 140. 27.
The image forming method described in 1 .. 28. The first toner, the second toner and the third toner are any of magenta toner, cyan toner and yellow toner, and the magenta toner,
28. The image forming method according to claim 27, wherein a full color image is formed by combining the cyan toner and the yellow toner. 29. The image forming method, further comprising a step of conveying the transfer material to a third image forming unit before fixing after performing the second transfer in the second image forming unit, A step of forming a third toner image by the third image forming means of the third image forming unit, applying a third transfer bias to the formed third toner image, and applying the third transfer bias to the third image forming unit. In the third transfer portion, the third transfer is performed on the transfer material on which the first toner image and the second toner image are transferred, and the transfer material is transferred to the fourth image forming unit. A step of conveying, a step of forming a fourth toner image by a fourth image forming unit of the fourth image forming unit,
A fourth transfer bias is applied to the formed fourth toner image to cause the fourth transfer portion of the fourth image forming unit to
A step of performing a fourth transfer onto the transfer material onto which the first toner image, the second toner image and the third toner image have been transferred, and the first transfer onto the transfer material. A step of fixing the toner image, the second toner image, the third toner image, and the fourth toner image on the transfer material by the fixing means, and the second transfer portion and the third transfer portion. Of the transfer material in the conveying direction is longer than the distance between the transfer portion and the transfer portion, and the length of the transfer material in the conveying direction is larger than the distance between the third transfer portion and the fourth transfer portion. Longer, the first transfer bias, the second transfer bias, the third transfer bias
And the fourth transfer bias are different from each other, and the third toner and the fourth toner forming the third toner image are different from each other.
The fourth toner forming the toner image of
-1 has a shape factor of 100-180 and SF-2 has a shape factor of 100-140.
6. The image forming method according to item 6. 30. The first toner, the second toner, the third toner, and the fourth toner are any of magenta toner, cyan toner, yellow toner, and black toner, and the magenta toner. 30. The image forming method according to claim 29, wherein a full color image is formed by combining the cyan toner, the yellow toner, and the black toner. 31. (i) A first toner image forming unit for forming a first toner image, and a first transfer bias of the first toner image formed by the first image forming unit. A first image forming unit having a first transfer means for applying and transferring to a transfer material at the first transfer portion;
i) A second toner image forming unit for forming a second toner image and a second transfer bias applied to the second toner image formed by the second image forming unit to obtain a second toner image. Second image forming means having a second transfer means for transferring the first toner image to the transfer material transferred at the transfer portion, and (iii) the first image transferred to the transfer material. Fixing means for fixing the toner image and the second toner image to the transfer material, and (iv) the transfer material to the first image forming unit, the second image forming unit and the fixing means. In the image forming apparatus having at least a transporting unit for sequentially transporting, the length of the transfer material in the transport direction is longer than the distance between the first transfer unit and the second transfer unit. And the second transfer bias is different in magnitude. , The first toner forming the first toner image and the second toner forming the second toner image are both SF-
The image forming apparatus is characterized in that 1 has a shape factor of 100 to 180 and SF-2 has a shape factor of 100 to 140. 32. The image forming apparatus according to claim 31, wherein an interval between the first transfer portion and the second transfer portion is 110 mm or less. 33. The image forming apparatus according to claim 31, wherein an interval between the first transfer portion and the second transfer portion is 100 mm or less. 34. The second transfer bias is set to be higher in polarity opposite to the charging polarity of the second toner with reference to the first transfer bias. The image forming apparatus according to any one of 31 to 33. 35. The first toner and the second toner each have a shape factor of 100 to 160 for SF-1 and 100 to 135 for SF-2. The image forming apparatus according to any one of 31 to 34. 36. The first toner and the second toner each have a shape factor of 100 to 140 for SF-1 and 100 to 120 for SF-2. The image forming apparatus according to any one of 31 to 34. 37. The image forming apparatus according to claim 31, wherein each of the first toner and the second toner has a residual monoer content of 1000 ppm or less. 38. The image forming apparatus according to claim 31, wherein each of the first toner and the second toner has a content of residual mona of 500 ppm or less. 39. A toner having a weight average particle diameter within the range of 1 to 9 μm and a coefficient of variation (A) in the number distribution of 35% or less for both the first toner and the second toner. The image forming apparatus according to claim 31, further comprising particles. 40. The first toner and the second toner each have a mixture of toner particles and a fine powder having a hydrophobicity of 60% or more. The image forming apparatus according to item 1. 41. The first toner and the second toner each include a mixture of toner particles and a fine powder having a hydrophobicity of 90% or more. The image forming apparatus according to item 1. 42. Each of the first toner and the second toner comprises toner particles, a hydrophobized inorganic fine powder a, and a hydrophobized silicon compound b having a larger particle size than the inorganic fine powder a. 4. A mixture according to claim 3.
The image forming apparatus according to any one of 1 to 39. 43. The inorganic fine powder a has an average particle size of 3 to 90.
nm, and the silicon compound b has an average particle size of 30 to 120.
43. The image forming apparatus according to claim 42, wherein the image forming apparatus has a wavelength of nm. 44. The image forming apparatus according to claim 42 or 43, wherein the inorganic fine powder a has a hydrophobicity of 60% or more. 45. The image forming apparatus according to claim 42 or 43, wherein the inorganic fine powder a has a hydrophobicity of 90% or more. 46. The first image forming means comprises a first latent image holding member for holding a first electrostatic latent image, and a first latent image holding member for primary charging the first latent image holding member. A first charging unit, a first latent image forming unit for forming the first electrostatic latent image on the first charged latent image holding unit, and a latent image holding unit. The image forming apparatus further includes a first developing unit that holds a first toner for developing the first electrostatic latent image to form the first toner image, and the second image forming unit, A second latent image holding member for holding a second electrostatic latent image, a second charging unit for primary charging the second latent image holding member, and the second primary charged second charging unit. Second latent image forming means for forming the second electrostatic latent image on the latent image holding member, and the second electrostatic latent image held on the latent image holding member is developed to develop the second electrostatic latent image. 2 to form a toner image The image forming apparatus according to any one of claims 31 to 45, characterized in that it has a second developing means for carrying a second toner. 47. The first latent image carrier and the second latent image carrier are both measured by X-ray photoelectron spectroscopy (XPS) of fluorine atoms and carbon atoms present on the surface of the latent image carrier. The image forming apparatus according to claim 46, wherein the abundance ratio (F / C) is within the range of 0.03 to 1.00. 48. The first latent image carrier and the second latent image carrier are both measured by X-ray photoelectron spectroscopy (XPS) of silicon atoms and carbon atoms present on the surface of the latent image carrier. The image forming apparatus according to claim 46, wherein the abundance ratio (Si / C) is within a range of 0.03 to 1.00. 49. The first charging means is a non-contact charging means for charging the surface of the first latent image holding body in a non-contact manner, and the second charging means is the second latent image holding means. 49. The image forming apparatus according to claim 46, which is a non-contact charging unit that charges the body surface in a non-contact manner. 50. The first charging unit is a contact charging unit that contacts and charges the surface of the first latent image holding member, and the second charging unit is the second latent image holding member. 47. A contact charging unit that contacts a surface to be charged.
49. The image forming apparatus according to any one of 48 to 48. 51. The first image forming device and the second image forming device are both carried on the developer carrying member in the developing area, rather than on the space between the latent image holding member and the developer carrying member. The developer has a larger layer thickness, and has a contact development system in which the layer of the developer on the developer carrying member is brought into contact with the surface of the latent image holding member to develop with the toner of the developer. The image forming apparatus according to any one of claims 46 to 50, wherein: 52. The image forming apparatus according to claim 51, wherein the developer is a two-component developer having a toner and a magnetic carrier. 53. The image forming apparatus according to claim 51, wherein the developer is a one-component developer containing toner. 54. The first image forming means and the second image forming means are both cleaning for removing toner existing on the surface of the latent image holding body after transfer between the transfer portion and the charging means. 54. Any one of claims 51 to 53, characterized in that the developing means does not have a means, and the developing means also functions as a cleaning means for collecting and cleaning the toner present on the surface of the latent image holding body after transfer. The image forming apparatus described. 55. The first image forming unit and the second image forming unit are both carried on the developer carrying member in the developing area, rather than on the gap between the latent image holding member and the developer carrying member. The layer thickness of the developed developer is smaller, and the layer of the developer on the developer carrier is not in contact with the surface of the latent image carrier from the developer carrier to the surface of the latent image carrier. The image forming apparatus according to any one of claims 46 to 50, further comprising a non-contact developing method of flying and developing with the toner of the developer. 56. The image forming apparatus according to claim 55, wherein the developer is a one-component developer containing toner. 57. The image forming apparatus further includes a third image forming unit in addition to the first image forming unit and the second image forming unit, and the third image forming unit. Applies a third transfer bias to the third toner image forming unit for forming the third toner image and the third toner image formed by the third image forming unit, The transfer unit has a third transfer unit for transferring the first toner image and the second toner image to the transfer material, and the second transfer unit and the third transfer unit. The length of the transfer material in the conveying direction is longer than the distance between the transfer member and the first transfer bias, the second transfer bias, and the third transfer bias.
And the transfer bias of No. 1 are different from each other.
57. The image forming apparatus according to claim 31, wherein -2 has a shape factor of 100 to 140. 58. The first toner, the second toner and the third toner are any of magenta toner, cyan toner and yellow toner, and the magenta toner,
The image forming apparatus according to claim 57, wherein a full-color image is formed by combining the cyan toner and the yellow toner. 59. The image forming apparatus further includes a third image forming unit and a fourth image forming unit in addition to the first image forming unit and the second image forming unit. The third image forming unit includes a third toner image forming unit for forming a third toner image and a third transfer of the third toner image formed by the third image forming unit. A third transfer unit for applying a bias to transfer the first toner image and the second toner image to the transfer material on which the first toner image and the second toner image have been transferred, The fourth image forming unit applies a fourth transfer bias to the fourth toner image forming unit for forming the fourth toner image and the fourth toner image formed by the fourth image forming unit. Then, at the fourth transfer portion, the first toner image and the second toner image A fourth transfer means for transferring the toner image and the third toner image onto the transfer material, the distance between the second transfer portion and the third transfer portion being greater than the distance between the second transfer portion and the third transfer portion. The length of the transfer material in the transport direction is longer, and the length of the transfer material in the transport direction is longer than the distance between the third transfer portion and the fourth transfer portion. Of the third transfer bias, the second transfer bias, the third transfer bias, and the fourth transfer bias are different from each other, and the third toner and the fourth toner have different sizes. Also SF-1
57 has a shape factor of 100-180 and SF-2 of 100-140.
The image forming apparatus according to any one of 1. 60. The first toner, the second toner, the third toner, and the fourth toner are any one of magenta toner, cyan toner, yellow toner, and black toner, and the magenta toner. 60. The image forming apparatus according to claim 59, wherein a full color image is formed by combining the cyan toner, the yellow toner, and the black toner.