JP3313991B2 - Developing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device for an image forming apparatus such as a printer or a copying machine using an electrophotographic method. In particular, the present invention relates to a developing device having a developer amount regulating unit that regulates a developer amount on a surface of a developer carrier such as a developing roller.

[0002]

2. Description of the Related Art An image forming apparatus using an electrophotographic method has a slightly different structure depending on the type of developer used.
The configuration is almost the same regardless of whether a component-based developer is used or a non-magnetic one-component developer is used. The difference in mechanism is that in the case of a magnetic one-component developer, only a magnet is required in a developer carrier such as a developing sleeve.

Accordingly, here, as a conventional example, a non-magnetic 1
A developing device using a component developer will be described with reference to FIG.

Conventionally, as shown in FIG. 5, for example, as shown in FIG. 5, this type of developing device 101 faces a photosensitive member 100 which is an image bearing member which rotates in the X direction in FIG. Roller 102, which is a developer carrying member for forming
And the developing roller 10 is rotated in the Z direction in FIG.
2 is a non-magnetic one-component developer (hereinafter abbreviated as developer) T
Supply roller 104, a developing blade 103 which is a development regulating means for regulating the amount of application and charge of the developer T on the developing roller 102, a hopper 106 for storing the developer T, And a blowout prevention sheet 105 for preventing the developer T in the hopper 106 from scattering from the side.

When a magnetic developer is used, a magnet is required in the developing roller 102, but the supply roller 104 is often unnecessary. Also,
In order to prevent the developer T from scattering, a blowing prevention sheet 10
Instead of 5, a magnetic member can be disposed in the same region for collecting the developer or preventing the developer from scattering.

In this type of developing device, the developing roller 102 is pressed or brought into contact with the photoreceptor 100 to perform the development, so that it is necessary to use a developing roller 102 having an appropriate elasticity. In particular, when the photoconductor 100 is a rigid body, it is an essential requirement that the developing roller 102 be formed of an elastic body in order to avoid damaging the photoconductor 100. Normally, the developing roller 102 is formed by forming a solid type silicone rubber having a thickness of several mm around a stainless steel or aluminum rigid core metal and forming it into a roller shape, or developing a material that enhances the charge imparting property to the developer. A roller further coated on silicone rubber is used.

Further, the regulating blade 103 preferably has a structure in which a rigid edge portion such as stainless steel is cut into the developing roller 102 in order to carry the developer T sufficiently charged on the developing roller 102 in a thin layer.

On the other hand, the developing device 101 forms a developing electric field in a developing region by applying a developing bias to the developing sleeve 102 from a power supply (not shown). Then, the electrostatic latent image formed on the surface of the photoreceptor 100 by means (not shown) is developed with a developer T carried on the surface of the developing roller 102 with a mirror image and is visualized. During this development, the residual developer T ′ remaining on the surface of the developing roller 102 is collected in the hopper 106 via the supply roller 104.

The developing device 101 basically uses an insulating non-magnetic one-component developer. Further, the supply of the developer T from the supply roller 104 to the developing sleeve 102 is performed in a rubbing region between the supply roller 104 and the developing sleeve 102 by a mirror force generated by the developer T being frictionally charged. (In the case of a magnetic developer, a magnetic force is applied to the supply and transport of the developer, as is well known.) The supply amount of the developer T to the developing sleeve 102 is adjusted by the developing roller 102 and the supply roller 104. Is performed with a peripheral speed difference of

The developing device 101 of this type does not require a magnetic force to transport the developer T, so that the developer is demagnetized, which is particularly advantageous for forming a color image.

[0011]

However, the conventional example described above has the following problems because the blade made of metal such as stainless steel is configured to contact the developing roller 102 having elasticity.

FIG. 6 shows a cross section near the contact area between the developing roller 102 and the developing blade 103.

The developing blade 103 includes a supply roller 104
Thus, the developer T supplied onto the developing roller 102 is regulated to a predetermined amount in the contact area. Normally, the multi-layer applied developer T is restricted to one or two layers in the contact area. This restriction is applied to the developing roller 10 in the contact area.
Since friction is generated between the developing blade 2 and the developing blade 103 and the developer T, frictional heat is generated in the contact area. When heat is generated in the contact area, the developer T softens, and as shown in FIG. 7, the developer is easily fused near the edge of the developing blade 103 (developer fusion T2).

Conventionally, since the developing blade 103 is made of a metal such as stainless steel or phosphor bronze, the releasability from the developer T is extremely poor, and if the softened developer T adheres to the edge of the developing blade 103 once, Cannot be easily removed.

The developer adhering to the edge of the developing blade 103 is always subjected to frictional heat and melts, resulting in a developer fusion T2. In particular,
This phenomenon occurs remarkably in low-melting-point developers for energy-saving fixing, which are widely used in recent years.

When the developer fusion T2 occurs at the edge of the developing blade 103, as shown in FIG.
2, white stripes 107 are generated in the coat layer of the developer on the second. As a result, white stripes appear on the output image,
Image degradation will occur.

The above-mentioned problem occurs because the developing blade 103 has low releasability from the developer. That is, in the conventional example, it is difficult to stably form a uniform developer coating layer without the white stripes 107 on the developing roller 102 over a long period of time. If used, this is one of the causes of lowering the durability of the developing device.

An object of the present invention is to prevent the developer from being fused at the edge of the development control means, and to form a stable and uniform developer coat layer on the developer carrier over a long period of time. It is another object of the present invention to provide a developer amount regulating unit which prevents image deterioration for a long period of time and improves durability, and a developing device using the same.

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

According to a first aspect of the present invention, an object of the present invention is to provide a developer carrier having an elastic layer opposed to an image carrier, and a surface of the developer carrier. A developer amount regulating means for regulating the amount of developer for forming a developer layer on the image carrier by forming the developer layer on the surface of the developer carrier close to or in contact with the image carrier; in the developing device to visualize the electrostatic latent image to be, above
The developer amount regulating means is formed so as to have an L-shaped cross section.
The edge portion bent in an L shape is the developer
Contact the surface of the developer carrier along the axis of the carrier
This is achieved by having a developer release layer on at least the edge portion .

According to the second invention of the present application,
The above object is achieved when the developer release layer of the developer amount regulating means of the first invention has conductivity.

According to the third aspect of the present invention,
The above object is attained by the developer amount regulating means of the first invention or the second invention, wherein the charge polarity of the developer release layer is opposite to the charge polarity of the developer in a triboelectric series. .

Further, according to the fourth invention of the present application,
Above object, the developer releasing layer of the developer amount regulating means one invention of the first invention to the third invention can be achieved by a main component silicone resin.

According to the fifth invention of the present application,
The above object is achieved by a developer release layer of the developer amount regulating means one invention of the first invention to the third invention is composed mainly of fluorocarbon resin.

According to the sixth aspect of the present invention,
The above object is achieved by a shape factor SF-1 of the developer of one invention of the first invention to the fifth invention is in the range and SF-2 of 100 to 120 at 100 to 140 .

According to the seventh aspect of the present invention,
Above object, the developer of the sixth invention is, some or all can be achieved by those produced by a polymerization method.

According to the eighth aspect of the present invention,
The above object is achieved by the developer of the seventh invention having a core / shell structure, and the shell is formed by a polymerization method.

Further, according to the ninth invention of the present application,
The above object is attained by the fact that the main component of the core of the eighth invention comprises a low softening point substance, and the melting point of the low softening point substance is 40 to 90 ° C.

Further, according to the tenth aspect of the present application, that the above object, the developer of one invention of the first invention to the ninth invention is of the non-magnetic one-component Is achieved by

[0034] The 11 th aspect of the present application, the object is, the developer of one invention of the first invention to the tenth aspect there is coverage by the external additive 5-99
%.

[0035]

[0036]

[0037]

[0038]

[0039]

In the first invention according to the present application, the developer amount regulating means includes an edge portion bent in an L-shape.
Controls the amount of developer by contacting the developer carrier
The contact state at the time of contact is stable and a uniform developer layer is formed.
At that time, since the organic developer release layer on the edge portion, edge
Developer fusing near di is Ru is prevented.

Further, in the second invention according to the present application, the developer release layer of the developer amount regulating means of the first invention has conductivity, and the developer is electrically charged by Coulomb force. To prevent strong solid fixation.

Further, in the third invention according to the present application, the charge polarity of the developer release layer of the developer amount regulating means of the first invention or the second invention is different from the charge polarity of the developer with the charge polarity of the developer. It has the opposite polarity in the charging sequence, and charges the developer to the opposite polarity.

[0043] Further, in the fourth aspect of the present application, the developer releasing layer of the developer amount regulating means one invention of the first invention to the third invention mainly silicone resin As a component, it exhibits high releasability.

[0044] Further, in the fifth aspect of the present application, the first invention to the third main one developer release layer fluororesin developer amount controlling means of the invention of the invention As a component, it exhibits high releasability.

Further, in the sixth invention of the present application, the shape factor SF-1 of the developer of one invention of the first invention to the fifth invention and SF in 100 to 140
When -2 is in the range of 100 to 120, the degree of spheroidization is good, and it is difficult to charge, and the charged developer does not easily adhere.

In the seventh invention according to the present application, a part or all of the developer of the sixth invention is produced by a polymerization method to produce a developer having a high degree of sphericity.

In the eighth invention according to the present application, the developer according to the seventh invention has a core / shell structure, and the shell is formed by a polymerization method, and the developer having a core-free bulk is formed by a polymerization method. compared to a more obtained developer, is that easy and Do removal of residual monomer in post-treatment step after the polymerization step.

In the ninth invention according to the present application, the main component of the core of the developer according to the eighth invention comprises a low softening point substance, and the melting point of the low softening point substance is 40 to 90 ° C. , and the excellent high-temperature offset property of the developer, and fixability that Do good.

[0049] Further, in the tenth invention of the present application, a developer is non-magnetic one-component developer of one invention of the first invention to the ninth invention, the non-magnetic single The fusion of the component developer to the developer amount regulating means is prevented for a long time.

[0050] Further, in the eleventh aspect of the present application, the developer of one invention of the first invention to the tenth invention, the coverage of coating the surface with an external additive 5 99%, which further improves the releasability.

[0051]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) FIGS. 1 and 2 show a first embodiment of a developing device and a developer amount regulating means of the present invention.

FIG. 1 is a sectional view of a developing apparatus using the developer amount regulating means of the present invention. FIG. 2 is a sectional view of the developer amount regulating means of the present invention.

This developing device includes a developing roller 2 which is a developer carrier opposed to an image carrier (see photoconductor 0 in FIG. 4), and a developer T provided in contact with the developing roller 2.
And a developing blade 3 that is a developer amount regulating unit that contacts the developing roller 2 to regulate the amount of the developer T on the developing roller 2 to a predetermined amount.

In this embodiment, the developing roller 2 is formed by attaching a stainless steel core having an outer diameter of 8 mm to a volume resistance value of 1 mm.
0 ⁶ an elastic layer was 4mm formed by Ωm silicone rubber (solid rubber), and an elastic developing roller having an outer diameter of 16 mm. A coat layer for adding a charge amount to the developer may be provided on the surface layer. The developing roller 2 has a hardness of JIS-
A is about 45 ° and the surface roughness Rz is about 6 μm.

The developing blade 3 is formed by bending one end of a stainless steel plate into an L-shape, and bringing the L-shaped bent edge portion into contact with the outer peripheral surface of the developing roller 2. The developing blade 3 regulates the developer T on the developing roller 2 to a predetermined amount at the edge portion. In the present embodiment, as shown in FIG. 1, the state is regulated from a multilayer coating state to a single-layer coating state (normally, one to two layers). The contact pressure of the developing blade 3 against the developing roller 2 is 30 g / c
m.

The developing blade 3 is provided with a developer release layer 5 near the edge region. In the present invention, the developing blade 3 is provided with a developer release layer 5 at least in a region in contact with the developer. This developer release layer 5 is the greatest feature of the present invention. The developer release layer 5 will be described later in detail.

The supply roller 4 has a function of supplying the developer T to the surface of the developing roller 2 and removing the residual developer that has not been subjected to the development in the developing step from the surface of the developing roller 2. The supply roller 4 is arranged to have the same potential as the developing roller 2. In the present embodiment, the supply roller 4 is made of an insulating urethane sponge rubber having a volume resistance value of 10 ¹⁴ Ωcm on a stainless steel core bar having an outer diameter of 8 mm.
m is an elastic sponge roller having an outer diameter of φ16 mm. The supply roller 4 has a nip approximately 2 nips between the supply roller 4 and the developing roller 2.
mm.

As shown in FIG. 1, the developing roller 2 and the supply roller 4 rotate in the Y and Z directions, respectively. In the present embodiment, the developing roller 2 is 175 mm / s
ec, and the supply roller 4 rotates at 70 mm / sec. The developing roller 2 and the supply roller 4
The difference between the peripheral speed of the supply roller 4 and the peripheral speed of the development roller 2 is 60% in terms of the supply of the developer T to the development roller 2 and the removal of the developer T from the development roller 2. It is set.

Next, the non-magnetic one-component developer T used in the developing device of this embodiment will be described.

In the present embodiment, a low-melting spherical toner of non-magnetic one component is used as the developer T. The spherical developer T has a weight average particle diameter of about 6 μm, a shape factor SF-1 (sphericity) of 100 to 140,
SF-2 (degree of unevenness) was in the range of 100 to 120.

Here, the degree of spheroidization of the spherical developer (the sum of the degree of sphericity and the degree of unevenness is referred to as the degree of spheroidization in the present specification) will be described.

The degree of spheroidization of the developer can be indicated by using the shape factors SF-1 and SF-2 of the developer. SF-1 and SF-2 are Hitachi FE-SEM
Using (S-800), 100 developer images were randomly sampled, and the image information was introduced into an image analyzer (Luzex3) manufactured by Nicolet via an interface.
Analysis is performed, and the value obtained by calculation according to the following equation is defined.

SF-1 = {(MXLNG) ² / AREA} × (π / 4) × 100 SF-2 = {(PERI) ² / AREA} × (1 / 4π) × 100 (MXLNG: absolute maximum length, (AREA: developer projected area, PERI: perimeter) SF-1 shows a degree of sphere, and when it exceeds 140, it becomes more irregular than a sphere. SF-2 indicates the degree of unevenness, and when it exceeds 120, unevenness on the surface of the developer becomes remarkable.

Therefore, the degree of spheroidization of the developer is SF-1
(Spherical degree) is preferably in the range of 100 to 140, and SF-2 (degree of unevenness) is preferably in the range of 100 to 120. The reason is that if the degree of spheroidization of the developer is poor, it becomes easy to charge the electric charge, and the charged developer adheres to the developing blade 3 to deteriorate the releasability. In particular, when the developing blade 3 has a high insulating property, the tendency of the releasability to deteriorate is increased.

As described above, the developer T having a high degree of spheroidization is
It is obtained by producing by a polymerization method.

In particular, a developer having a core / shell structure and a shell portion produced by polymerization is preferable. This makes the surface portion of the developer by a polymerization method. That is, pre-toner (monomer composition) particles are present in the dispersion medium, and the surface side portion is generated by a polymerization reaction. The advantage of this structure is that a developer having a high degree of spheroidization can be easily manufactured. That is,
Compared with a developer obtained by a polymerization method as a bulk having no core, polymerizing only the shell portion has an advantage that residual monomers can be easily removed in a post-treatment step after the polymerization step.

Further, it is preferable to use a low softening point substance as a main component of the core. Specifically, ASTM D34
The main peak value measured according to 18-8 is 40
Compounds that are between -90 ° C are preferred.

The range of the maximum peak value is preferably from 40 to 9
The reason for setting the temperature to 0 ° C. is as follows. When the maximum peak value is less than 40 ° C., the self-cohesive force of the low softening point substance becomes weak, and as a result, the high-temperature offset property becomes weak. on the other hand,
When the maximum peak value exceeds 90 ° C., the fixing temperature increases.

The maximum peak value range of 40 to 90
Paraffin wax, polyolefin wax, Fischer-Tropsch wax,
Examples include amide waxes, higher fatty acids, ester waxes and derivatives or graft / block compounds thereof.

Further, a low softening point substance is contained in the developer.
It is preferable to add 30% by weight.

The reason for adding 5 to 30% by weight is as follows. Addition of less than 5% by weight places a burden on the removal of the above-mentioned residual monomers. On the other hand, when it exceeds 30% by weight, coalescence of the developer particles tends to occur during granulation, and a particle having a wide particle size distribution is easily generated.

Further, it is preferable that the surface of the developer is coated with an external additive (fluidity imparting agent) so as to enhance the releasability. The external additive coverage on the surface of the developer is preferably from 5 to 99%, more preferably from 10 to 99%, for the purpose of enhancing the releasability.

The external additive coverage on the developer surface is as follows:
Using FR-SEM (S-800) manufactured by Hitachi, 100 developer images were randomly sampled, and the image information was introduced into an image analyzer (Luzex3) manufactured by Nicole via an interface, and analyzed. Performed and calculated.

As external additives, for example, metal oxides (aluminum oxide, titanium oxide, strontium titanate,
Cerium oxide, magnesium oxide, chromium oxide, tin oxide, zinc oxide, etc., nitride (silicon nitride, etc.), carbide (silicon carbide, etc.), metal salt (calcium sulfate, barium sulfate, potassium carbonate, etc.), fatty acid metal salt ( Calcium stearate and calcium stearate), carbon black and silica.

These external additives may be used alone or in combination of two or more. The external additive is developer particles 1
With respect to 00 parts by weight, 0.01 to 10 parts by weight is used,
Preferably, 0.05 to 5 parts by weight is used.

Next, the developing blade 3 of the present invention will be described in more detail with reference to FIG.

As described above, the developing blade 3 was formed by bending one end of a stainless steel plate into an L-shape, and the developer release layer 5 was formed at the edge. This developer release layer 5
It is formed by coating a coating resin of about 20 μm. As the coating resin used as the developer release layer 5, a resin having excellent release properties is used.

The releasability is determined by the contact angle θ with water.
(Degree), and evaluated on a wetting scale Wi (dyne / cm).

Here, the contact angle θ (degree) and the scale Wi of the wetting
Next, the method of obtaining is described.

Assuming that the surface tension of the coating resin is γs, the interface tension between the coating resin and water is γsL, and the surface tension of water is γL, the relationship is as shown in FIG.

.Gamma.s = .gamma.sL + .gamma.L cos.theta. By the way, the wetting scale Wi is Wi = .gamma.s-.gamma.sL ...
It is.

Therefore, according to the equation, Wi = γL co
sθ ... is obtained.

In the present embodiment, since a negative developer is used as the developer T, a silicone resin having a positive polarity which is triboelectrically opposite to the negative polarity of the developer is used as the coating resin. Was. For comparison of the effects of the silicone resin of the present embodiment, a polyamide having the same positive polarity was used in a comparative example.

The releasability of the coating resin of the silicone resin and the polyamide is shown in Table 1 below (Table 1 shows PFA (ethylene tetrafluoride resin) described later).
Is also shown).

[0086]

Table 1 Evaluation items Silicone Polyamide PFA wetting scale (dyne / cm) -25 25 -30 Contact angle (degree) 100 77 120 According to Table 1, it is understood that the release properties of silicone resin are superior to polyamide. .

In this embodiment, specifically, 12.5 parts by weight of carbon and 5 wt% of a silane coupling agent as a curing agent are added to a silicone resin, and dispersed and stirred at room temperature of about 20 ° C. for 24 hours. Coating Resin A was prepared.

Then, this coating resin A was applied to the edge of a stainless steel plate having one end bent into an L-shape by about 2
After coating with 0 μm, the coating was placed in a thermostat set at 180 ° C. for about 2 hours, and dried and cured to form a developing blade 3 of the present invention.

At the same time, as a comparative example, 12.5 parts by weight of carbon was dispersed in polyamide to prepare a comparative coating agent in order to obtain the same resistance as that of the coating resin A. This comparative coating agent was coated on the edge of a stainless steel plate having one end bent into an L-shape for about 20 μm, and then placed in a thermostat set at 180 ° C. for about 2 hours to perform a drying and curing treatment. After drying for minutes.

As described above, the developing blade 3 of this embodiment and the blade of the comparative example were prepared.

Here, in the developing blade 3 and the comparative example blade, carbon was added to silicone resin and polyamide, respectively, to make the developer release layer 5 conductive. The reason why the conductive material is made conductive is to prevent the electric strong fixing of the developer T due to the Coulomb force, that is, to enhance the releasability.

Next, the developing blade 3 prepared as described above and the comparative example blade were mounted on the developing device shown in FIG. 1, and a paper passing test was performed by the image forming apparatus shown in FIG. The evaluation items in this test are: Developing roller 2
1. Upper developer coating status; This is an image deterioration state (white streak generation state). The evaluation was performed every 100 sheets.

The results are shown below. 1. State of Developer Coating on Developing Roller 2 According to the developing blade 3 of the present embodiment, although 10,000 sheets were passed, white stripes as shown in the conventional example did not occur in the developer coating layer on the developing roller 2.

On the other hand, 5
White streaks occurred on about 00 sheets, and became noticeable after 1000 sheets. 2. Image Forming State According to the developing blade 3 of this embodiment, 10,000 sheets were passed, but all were good and no image deterioration occurred.

On the other hand, according to the comparative example blade,
After 1000 sheets, white streaks appeared on the image.

After the evaluation was completed, the edge of the developing blade 3 was observed. In this embodiment, no fusion of the developer was confirmed. In the comparative example blade, the fusion of the developer was confirmed at the edge. .

That is, it is apparent that by using the silicone resin to improve the developer releasability in the area where the developing blade 3 is in contact with the developing roller 2 (near the edge portion), it is possible to prevent the developer from sticking in this area. And

In the present invention, the reason that the developing blade 3 prevents the fusion of the developer is that even if the developer is fixed to the developer release layer 5 near the edge of the developing blade 3, This is because, because of the excellent releasability, the fixed developer can be easily removed by the frictional force and the scraping force of the surface of the developing roller 2.

In this experiment, the developer releasing layer was made conductive to prevent strong electric fixation and to enhance the releasing property.

On the other hand, in the developing blade 3 and the comparative example blade, if a repulsion voltage of the same polarity as the developer T is applied to the stainless steel plate of each blade, the developer release layer 5 becomes insulative. You may. That is, in the present invention,
The developer release layer 5 may be insulative, but in this case, a repulsive electric field having the same polarity as the developer is formed on the developer release layer 5 to prevent strong electric fixation. Is desirable.

As described above, in the present invention, the occurrence of the developer fusion in the vicinity of the developing roller contact area (near the edge portion) of the developing blade, which has conventionally occurred, is prevented for a long time. Therefore, generation of white stripes in the developer coat layer on the developing roller is prevented for a long period of time, and image deterioration is prevented.

(Second Embodiment) In the first embodiment described above, the case where a negative polarity developer is used has been described. However, the present invention can be applied to a positive polarity developer. That is, in the second embodiment, the developer release layer 5 of the developing blade 3 when a positive polarity developer is used will be described.

In the second embodiment, the coating resin for the developer release layer 5 has a negative polarity in a charging series with respect to a positive polarity developer. As a resin having a negative polarity, for example,
Fluororesins are preferred, and among them, tetrafluoroethylene resin (PFA) is most suitable. It is clear from Table 1 that the releasability of PFA is excellent. The conductivity of the developer release layer 5 is also the same as that of the first embodiment, and it is desirable to disperse carbon black or the like to make it conductive, because it can prevent sticking due to electric force.

However, even if the developer release layer is made insulating,
If a negative voltage is applied to the stainless steel plate, sticking due to electric force can be prevented.

As in the second embodiment, as in the first embodiment, the occurrence of the fusion of the developer to the developing blade 3 and the development on the developing roller are prevented. This has the effect of preventing white streaks in the agent coating layer and preventing image deterioration.

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

As described above, according to the present invention, first according to the application
According to the invention, the developer amount regulating means is bent in an L-shape.
The contacted edge portion contacts the developer carrier,
Uniform development with stable contact when regulating the amount of developer
An agent layer can be formed. On the other hand, it is bent into such an L shape
When the edge abuts on the broken part, the force concentrates near the edge
In particular, the developer tends to be easily fused, but the edge portion has a developer release layer so that
Ru can be prevented developer fused around. like this
Furthermore, according to the present invention, the formation of a uniform developer layer and the amount of developer
It is possible to achieve both the prevention of the developer from being fused to the regulating means. As a result, generation of white stripes in the developer coat layer on the developer carrier can be prevented for a long period of time, and thus image deterioration can be prevented.

Further, according to the second invention of the present application,
Since the developer release layer of the developer amount regulating means of the first invention has conductivity, it is possible to improve the releasability by preventing the electric firm fixation of the developer due to Coulomb force.

According to the third aspect of the present invention,
Since the charge polarity of the developer release layer of the developer amount regulating means of the first invention or the second invention is opposite to the charge polarity of the developer in the triboelectric series, the friction between the developer and the developer is reduced. The developer can be charged to the opposite polarity.

Further, according to the fourth invention of the present application,
Since the developer releasing layer of the developer amount regulating means one invention of the first invention to the third invention is mainly composed of silicone resin, it is possible to exhibit high releasability.

Further, according to the fifth invention of the present application,
Since the developer releasing layer of the developer amount regulating means one invention of the first invention to the third invention is composed mainly of fluorocarbon resin and can exhibit high releasability.

According to the sixth invention of the present application,
The first shape factor of the developer of one invention of the invention to the fifth invention SF-1 of and SF-2 at 100 to 140
Is in the range of 100 to 120, and the degree of spheroidization is good, so that it is difficult to charge the electric charge, the charged developer hardly adheres, and the releasability can be improved.

According to the seventh invention of the present application,
In the sixth aspect , since part or all of the developer is produced by a polymerization method, a developer having a high degree of spheroidization can be produced.

Further, according to the eighth invention of the present application,
Since the developer of the seventh invention has a core / shell structure and the shell is formed by a polymerization method, a post-processing step after the polymerization step is performed in comparison with a developer obtained by a polymerization method as a bulk having no core. Thus, the residual monomer can be easily removed, and a developer having a high degree of spheroidization can be easily produced.

According to the ninth invention of the present application,
The main component of the core of the developer according to the eighth invention is composed of a material having a low softening point, and the melting point of the material having a low softening point is 40 to 90 ° C. Agent can be realized.

[0120] According to the tenth invention of the present application, the developer of one invention of the first invention to the ninth invention is a non-magnetic one-component developer, the non-magnetic one-component The fusion of the developer to the developer amount regulating means can be prevented for a long period of time, and it can contribute to the improvement of the quality of a color image.

[0121] The 11 th aspect of the present application, coverage coating the surface with the external additive in the developer of one invention of the first invention to the tenth invention is 5 to 99 %, The releasability can be further enhanced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a developing device using an embodiment of a developer amount regulating unit of the present invention.

FIG. 2 is an enlarged view of a developer amount regulating unit of FIG. 1;

FIG. 3 is an explanatory diagram illustrating the releasability of a developer release layer of a developer amount regulating unit in FIG. 1;

FIG. 4 is a schematic configuration diagram of an example of an image forming apparatus to which the present invention is applied.

FIG. 5 is a schematic configuration diagram illustrating the vicinity of a developing section of a conventional image forming apparatus.

FIG. 6 is an enlarged view showing the vicinity of a developer amount regulating unit in the developing section of FIG. 5;

FIG. 7 is a perspective view showing a state in which a developer is attached to a developer amount regulating unit in FIG. 6;

FIG. 8 is a perspective view showing a white stripe generated on a developer carrying member of the developing unit of FIG. 5;

[Explanation of symbols]

 0 Photoconductor (Image Carrier) 1 Developing Device 2 Developing Roller (Developer Carrier) 3 Developing Blade (Developer Amount Controlling Unit) 4 Supply Roller 5 Developer Release Layer T Developer

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-7-36278 (JP, A) JP-A-58-116559 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/08

Claims (11)

(57) [Claims] 1. A developer carrier having an elastic layer opposed to an image carrier, and a developer amount regulating means for regulating a developer amount for forming a developer layer on a surface of the developer carrier. comprising, by proximity or contact with the developer layer on the surface of the developer carrying member to the image bearing member, the developing device to visualize the electrostatic latent image formed on an image bearing member, the developer amount The restricting means is shaped so as to have an L-shaped cross section.
The edge portion bent in an L-shape is developed as described above.
Contacting the surface of the developer carrier along the axial direction of the developer carrier.
Touch to, developing apparatus is characterized by having at least the developer releasing layer on the edge portion. 2. A developer amount controlling means, a developing device according to claim 1, characterized in that the developer releasing layer is electrically conductive. 3. A developer amount controlling means, developing of claim 1 or claim 2 charge polarity of the developer releasing layer and we are the charge polarity and triboelectric series to the opposite polarity of the developer apparatus. 4. A developer amount controlling means, a developing device according to one of claims 1 to 3 developer release layer and be mainly composed of silicone resin. 5. The developer amount controlling means, a developing device according to one of claims 1 to 3 developer release layer and be mainly composed of fluorocarbon resin. 6. The developer has a shape factor SF-1 of 100 to 100.
The developing device according to any one of claims 1 to 5 , wherein 140 and SF-2 are in the range of 100 to 120. 7. A developer, a developing device according to claim 6, that some or all of those produced by a polymerization method. 8. The developing device according to claim 7 , wherein the developer has a core / shell structure, and the shell is formed by a polymerization method. 9. The main component of the core comprises a low softening point substance,
The developing device according to claim 8 , wherein the melting point of the low softening point substance is 40 to 90C. 10. A developer, a developing device according to one of claims 1 to 9, it is of the non-magnetic one-component. 11. The developer has a coverage of 5 to 5 with an external additive.
The developing device according to one of claims 1 to 10, to be 99%.