JP2008165106A - Developer amount regulating blade and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer amount regulating blade which does not contain environmental load substance and which will not rust over a long term, even under high temperature and high humidity. <P>SOLUTION: The developer amount regulating blade comprises a support member and a blade member, and regulates the amount of developer carried out by a developer carrier from a developer container, and the support member has a galvanized layer 2 on a steel plate 3, and a surface treatment layer 1 containing silica on the galvanized layer, and the blade member and the support member are welded. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a developer amount regulating blade for regulating the amount of developer used for developing and visualizing an electrostatic latent image formed on an image carrier, and a method for manufacturing the same.

  It is known to use a developer amount regulating blade for the purpose of regulating the layer thickness of a one-component non-magnetic developer (hereinafter also referred to as toner) carried and conveyed by a developer carrying member to a developing unit. A developer amount regulating blade is brought into contact with the developer carrying member, and the developer is regulated by regulating the toner layer thickness by passing the toner between contact portions between the developer amount regulating blade and the developer carrying member. A thin layer of toner is formed on the carrier. Furthermore, a method of imparting triboelectric charge (tribo) for developing a latent image to toner by friction at a contact portion between a developer amount regulating blade and a developer carrying member is known.

  The developer amount regulating blade is usually mounted on a developing device by forming a blade member and a support member (hereinafter, also referred to as a holder) by bonding or integral molding. As the blade member, there is a blade member obtained by laminating a resin thin plate or the like on a base material such as metal or rubber in addition to a rubber plate or a metal thin plate. The supporting member is made of metal, mainly plated steel plate and stainless steel, and has a thickness of 1 to 2 mm in order to have a strength that does not cause deformation such as distortion when incorporated in a developing device. Things are used.

  When the blade member is a rubber blade, a method of adhering to the holder using an adhesive or a method of integrally molding with the holder is used. However, when the blade member is made of rubber, the elastic modulus is lower than that of metal, so plastic deformation occurs inside the rubber when used for a long period of time, and the set pressure on the developer carrier is reduced, resulting in development efficiency. There are problems such as affecting

  In order to solve this problem, many blade members in which a resin film is laminated on a thin metal plate have been proposed. Since these blade members are difficult to be bonded to the support member by an adhesive, joining by welding is used. Thus, a holder in which a galvanized plate is formed on a steel plate suitable for welding has been proposed (for example, Patent Document 1).

  However, a holder made of a galvanized steel sheet may generate rust on the surface under high temperature and high humidity. When rust floats in the developing container and adheres to the image area, there is a problem that causes an image defect.

  In particular, in recent years, a method for reducing the toner particle diameter has been proposed in order to achieve high image quality. While such a toner can faithfully develop a very small dot latent image, toner that is carried to the developing unit without being sufficiently in contact with the developer amount regulating blade and the developer carrying member is generated, and a high image due to insufficient charge amount. In some cases, the concentration could not be obtained. In view of this, a developing system in which charge is injected into toner by applying a voltage to the developer amount regulating blade and the developer carrying member to generate a potential difference has been actively adopted. When grounding from the holder of the developer amount regulating blade, rust on the surface of the holder affects the voltage, and the toner charge amount may change, and improvement has been demanded.

  For the purpose of preventing the rust of the plated layer, a chromate treatment or the like is generally performed. This chromate treatment includes electric chromate treatment, reactive chromate treatment, and coating chromate treatment formed by drying without washing with water after coating. There has been proposed a metal holder for a developer amount regulating blade in which the holder is formed of a steel plate having a chromate film and an organic lubricating film layer on an electrogalvanized steel sheet (for example, Patent Document 2).

The rust preventive layer formed by such a chromate treatment has a self-repair function by hexavalent chromium in addition to its high barrier property. Therefore, the chromate treatment has excellent corrosion resistance even in the damaged part, and is widely used as an important basic technology for corrosion prevention of galvanized steel sheets and the like. However, a product containing a harmful element such as hexavalent chromium has a disadvantage that it has a high environmental load and cannot be recycled, and has been required to be improved.
JP 2003-280364 A Japanese Patent Laid-Open No. 7-334059

  The present invention has been made to solve the above-described problems in the developer amount regulating blade. An object of the developer amount regulating blade of the present invention is to provide a developer amount regulating blade that does not contain an environmental load substance and does not generate rust for a long time even under high temperature and high humidity.

  The present invention relates to a developer amount regulating blade that includes a support member and a blade member, and regulates the amount of developer carried out of a developer container by a developer carrier, and at least the support member is made of zinc on a steel plate. A developer amount regulating blade having a plated layer and a surface treatment layer containing silica on a galvanized layer, wherein a blade member and a support member are welded.

  And a developer amount regulating blade comprising a support member and a blade member for regulating the amount of developer carried out of the developer container by the developer carrier, wherein the support member is made of zinc on the steel plate. Plating, forming a plated layer, forming a surface treatment layer on the galvanized layer, processing the steel plate into the shape of the support member, and forming the support member, and then the support member and the blade member And the step of forming the surface treatment layer has a step of applying a surface treatment liquid in which silica is added to the inorganic rust inhibitor and a step of drying and solidifying thereafter. And a developer amount regulating blade manufacturing method.

  The present invention has been made to solve the above-mentioned problems in the developer amount regulating blade, and provides a developer amount regulating blade that does not contain environmentally hazardous substances and does not generate rust even under high temperature and high humidity for a long period of time. To do.

  The present invention is a developer amount regulating blade for regulating the amount of developer carried out from a developer container by the developer carrying member. The developer amount regulating blade is composed of a blade member obtained by laminating a resin film on a thin metal plate and a support member (holder). At least the holder includes a zinc-based plating layer on the steel plate, and further on the zinc-based plating layer. And a surface treatment layer containing silica.

  Hereinafter, the present invention will be described in detail.

  In FIG. 1, an example of the supporting member which is embodiment of this invention is shown.

  In addition, the blade member (not shown) is formed by laminating a film made of a thermoplastic resin or a thermosetting resin on a metal thin plate. The metal thin plate is preferably phosphor bronze, SUS plate or the like having good elasticity. The thickness of the metal thin plate is preferably 0.08 mm or more and 0.15 mm or less. When the thickness is less than 0.08 mm, the contact pressure to the developer carrier and the toner is insufficient, and when it exceeds 0.15 mm, the stress on the toner is high, and fusion occurs early, causing image defects. This is not preferable.

  When a thermoplastic resin or a thermosetting resin is laminated on a metal thin film, polyamide, polyester, polyurethane, or the like that has a triboelectric chargeability suitable for the toner and can suppress the burden on the toner can be selected. These may be added with additives such as a conductive agent as necessary. These resins may be laminated on the entire contact side with the developer / developer carrying member, or may be laminated so as to exist only in the contact portion and the vicinity thereof.

  A support member (holder) to which the blade member is fixed is galvanized on the steel plate 3 to form a plated layer 2, and a surface treatment layer is formed on the plated layer 2.

  The method for forming the plating layer is not particularly limited, and for example, electroplating or hot dipping can be used. As the support member, stainless steel or the like can be used in addition to the steel plate, but these materials are collectively referred to as a steel plate.

  Furthermore, by applying a surface treatment liquid in which silica is added to an inorganic rust preventive agent to a steel plate 3 having such a galvanized plated layer 2 and drying and solidifying it, the same prevention as in chromate treatment is achieved. A surface treatment layer 1 having rusting power is formed. The silica is not particularly limited, but colloidal silica or secondary agglomerated silica is preferable because it increases the film strength in addition to the metal corrosion inhibiting function.

  In addition to the above, the plating layer formation, the surface treatment layer formation, and the process of processing the support member into the shape of the support member are not limited to those described above. After the plating layer is formed on the substrate, it may be processed into the shape of the support member, and then the surface treatment layer may be formed.

  As inorganic rust preventives to which these silicas are added, inorganic acid in which phosphate or phosphite or a mixture of phosphate and phosphite is dissolved improves corrosion resistance, lubricity during processing, etc. Therefore, it is preferable. When silica is added to the treatment liquid, the non-volatile content is preferably 0.5% by mass or more and 40% by mass or less. When the nonvolatile mass ratio is less than 0.5% by mass, the abundance in the film is small, and the corrosion resistance may be reduced. When the non-volatile content mass ratio exceeds 40% by mass, the denseness of the film tends to decrease, and the original barrier effect may not be sufficiently exhibited.

  The thickness of the steel sheet forming the galvanized layer is preferably from 1.2 mm to 1.6 mm. If the thickness is less than 1.2 mm, the strength may be insufficient. On the other hand, if the thickness is greater than 1.6 mm, press working becomes difficult.

The holder after the surface treatment is subjected to shear punching, bending processing, hole punching processing, and the like by metal press processing, preferably after degreasing, and bonded to the blade member by welding. As welding, spot welding with a YAG laser (Y ₃ Al ₅ O ₁₂ : Nd ³⁺ ) having high laser efficiency is preferable in order to suppress deformation due to welding to the blade member.

  FIG. 2 shows an example of a developing device using the developer amount regulating blade of the present invention.

  The developing device includes a developer container 12 containing a one-component developer 16 and a developer carrier 13 that is disposed opposite to an electrophotographic photosensitive member 11 that is an image carrier that rotates in the direction of arrow a in the figure. The electrostatic latent image on the electrophotographic photosensitive member 11 is developed and visualized as a toner image. The developer carrying member 13 has a substantially right half circumferential surface protruding into the developer container 12 as viewed in the figure, and a substantially left half circumferential surface exposed to the outside of the developer container 12 so as to face the electrophotographic photosensitive member 11. It is horizontally installed so that it can rotate freely. A minute gap is provided between the developer carrier 13 and the electrophotographic photosensitive member 11. The developer carrier 13 is rotationally driven in the direction of arrow b with respect to the rotational direction a of the electrophotographic photosensitive member 11.

  In the developer container 12, a developer amount regulating blade 14 of the present invention is provided above the developer carrier 13, and upstream of the developer amount regulating blade 14 in the rotation direction of the developer carrier 13. An elastic roller 15 is provided.

  The developer amount regulating blade 14 is provided so as to be inclined downward toward the upstream side in the rotation direction of the developer carrier 13, and abuts against the upper outer peripheral surface of the developer carrier 13 in the rotational direction. .

  The elastic roller 15 is in contact with a portion of the developer carrier 13 opposite to the electrophotographic photosensitive member 11 and is rotatably supported.

  In the developing device, the elastic roller 15 rotates in the direction of the arrow c, and the toner 16 is supported by the rotation of the elastic roller 15 and is supplied to the vicinity of the developer carrier 13 so that the developer carrier 13 and the elastic roller 15 are in contact with each other. The toner 16 on the elastic roller 15 is rubbed against the developer carrier 13 at the contact portion (nip portion) that comes into contact with the developer carrier 13, thereby adhering to the developer carrier 13.

  The developing device can also include a first voltage applying unit that applies a voltage to the developer carrying member and a second voltage applying unit that applies a voltage to the developer amount regulating blade of the present invention. It is. In this case, at least during execution of development, a voltage having an absolute value equal to or greater than the absolute value of the voltage applied to the developer carrying member is applied to the developer amount regulating blade. Specifically, the voltage applied to the developing bias preferably has a potential difference of about −100 to −300 [V].

  Thereafter, as the developer carrier 13 rotates, the toner 16 adhering to the developer carrier 13 enters between the developer amount regulating blade 14 and the developer carrier 13 between them. When passing between the developer amount regulating blade 14 and the developer carrier 13, it is rubbed by both the surface of the developer carrier 13 and the blade member 17, and is sufficiently charged by friction.

  The charged toner 16 escapes from the contact portion between the blade member 17 and the developer carrier 13, forms a thin layer on the developer carrier 13, and opposes the electrophotographic photoreceptor 11 with a small gap. It is conveyed to the developing unit. Then, by applying an alternating voltage in which an alternating current is superimposed on a direct current, for example, as a developing bias between the developer carrying member 13 and the electrophotographic photosensitive member 11 in the developing unit, the toner 16 on the developer carrying member 13 becomes an electron. The image is transferred corresponding to the electrostatic latent image on the photographic photosensitive member 11, and is attached to the electrostatic latent image and developed to be visualized as a toner image.

  The toner 16 remaining on the developer carrier 13 without being consumed in the development in the developing unit is collected in the developer container 12 from the lower part of the developer carrier 13 as the developer carrier 13 rotates.

  The collected toner 16 is peeled off from the developer carrier 13 by the elastic roller 15 at the contact portion with the developer carrier 13. At the same time, new toner 16 is supplied onto the developer carrier 13 by the rotation of the elastic roller 15, and the new toner 16 is conveyed again to the contact portion between the developer carrier 13 and the blade member 17.

  On the other hand, most of the removed toner 16 is conveyed and mixed into the toner 16 in the developer container 12 as the elastic roller 15 rotates, and the charged charge of the removed toner 16 is dispersed.

  FIG. 3 shows an example of an electrophotographic apparatus suitable for employing the developing device of the present invention.

  The photoreceptor 51 is an image carrier. The photoreceptor 51 is a drum type electrophotographic photoreceptor having a conductive support such as aluminum and a photosensitive layer formed on the outer peripheral surface thereof as basic constituent layers. The photoreceptor 51 is rotationally driven around the support shaft in the clockwise direction in the drawing at a predetermined peripheral speed.

  The surface of the photoconductor 51 that has been uniformly charged by the charging member 52 is then exposed to the target image information (laser beam scanning exposure, slit exposure of the original image, etc.) by the exposure means L, so that the peripheral surface thereof is exposed. An electrostatic latent image 53 corresponding to the target image information is formed.

  Next, the electrostatic latent image 53 is sequentially visualized as a toner image by the developing device 54.

  Next, the toner image is transferred from a paper feeding unit (not shown) by the transfer unit 55 in synchronization with the rotation of the photoconductor 51 and conveyed to the transfer unit between the photoconductor 51 and the transfer unit 55 at an appropriate timing. Transfer is sequentially performed on the surface of the material P. The transfer means 55 is a corona discharger (may be a roller type), and the toner image on the photosensitive member 51 surface side is transferred to the surface side of the transfer material P by charging from the back of the transfer material P with the opposite polarity to the toner. Will be transcribed. In addition, in color LBP (Laser Beam Printer: laser beam printer) that outputs a color image using four color toners, an intermediate transfer such as a roller or a belt is temporarily performed in order to develop and visualize each of the four color images. The toner is transferred to the body, and the toner image is transferred to the surface side of the transfer material P.

  The transfer material P onto which the toner image has been transferred is separated from the surface of the photoconductor 51 and is forwarded to the heat-fixing roll 58 for image fixing and output as an image formed product.

  The surface of the photoconductor 51 after the image transfer is cleaned by the cleaning means 56 after removal of adhering contaminants such as residual toner after transfer, and is repeatedly used for image formation.

  It should be noted that a plurality of elements of the electrophotographic apparatus such as the photosensitive member, the charging member, the developing device, and the cleaning unit can be integrated into the process cartridge. By doing so, the process cartridge can be attached to and detached from the apparatus main body. For example, the photosensitive member and the developing device and, if necessary, a charging member, a cleaning unit, and the like are integrally incorporated in the process cartridge, and can be detachably configured using a guide unit such as a rail of the apparatus main body.

  Examples of the electrophotographic apparatus that can use the developing device of the present invention include a copying machine, a laser beam printer, an LED printer, or an electrophotographic application apparatus such as an electrophotographic plate making system.

<Example>
In the following, the present description will be described in more detail with specific examples. The examples illustrate the invention, but the invention is not limited to these examples. In the examples, “part” means “part by mass”.

<Example 1>
A phosphor bronze having a thickness of 0.1 mm was press-punched to produce a blade member.

The holder used as a support member is a 1.2 mm steel plate (JINCOAT 21: trade name, manufactured by Nippon Steel Co., Ltd.) punched and bent, and an electrogalvanized layer is formed on both sides. . The electrogalvanized layer has a plating adhesion amount of 20 g / m ² and a plating layer thickness of about 2.7 μm. A surface treatment solution was applied on the electrogalvanized layer.

  After degreasing and cleaning with a hydrocarbon-based cleaning agent (Actrel 1130L: trade name, manufactured by Exxon Mobil), the blade member and support member are combined, spot welded with a YAG laser from the blade member side, and the developer amount is restricted. Created a blade.

  Next, the developer amount regulating blade 1 is mounted on a developer container (Lasershot (manufactured by Canon Inc .; product name)) and stored in an environment of high temperature and high humidity (temperature 40 ° C., humidity 95 RH%) for 30 days. After that, the developer amount regulating blade 1 was taken out and visually checked for the occurrence of rust.

In addition, evaluation of rust generation is
○: No rust is seen,
Δ: Rust less than φ2 mm is generated,
X: Rust of φ2 mm or more has occurred,
It was evaluated in three stages.

Further, the welded portion of the blade and the holder was enlarged and observed with a magnifying glass, and the welding state was visually confirmed. In addition, evaluation of a welding state is
○: No floating or peeling is observed over all welding points.
X: There is a floating or peeling part,
It was evaluated in two stages.

<Example 2>
A developer amount regulating blade was prepared in the same manner as in Example 1 except that a SUS plate having a thickness of 0.08 mm was used as the blade member. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

<Example 3>
As a blade member, a developer amount regulating blade was prepared in the same manner as in Example 1 except that 0.03 μm thick polyurethane was laminated on 0.1 mm thick phosphor bronze. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

<Example 4>
As a holder, a 1.2 mm steel plate coated with a surface treatment solution adjusted so that the mass ratio of colloidal silica having a primary particle diameter of 20 nm and phosphate is 0.5: 99.5 (Jincoat 21: trade name) A developer amount regulating blade was prepared in the same manner as in Example 1 except that Shinnippon Steel Co., Ltd. was used. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

<Example 5>
As a holder, a 1.2 mm steel plate coated with a surface treatment solution adjusted so that the mass ratio of colloidal silica having a primary particle size of 20 nm and phosphate is 20:80 (Jincoat 21: trade name, manufactured by Nippon Steel Co., Ltd.) A developer amount regulating blade 5 was prepared in the same manner as in Example 1 except that Sakai Co., Ltd. was used. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

<Example 6>
As a holder, a hot dip galvanized layer is formed on both sides, a coating amount of 20 g / m ² , a colloidal silica with a primary particle diameter of 20 nm and phosphate on a steel plate with a plating layer thickness of about 2.7 μm. Except for using a 1.2 mm steel plate (Silver Zinc 21: trade name, manufactured by Nippon Steel Corp.) coated with a surface treatment liquid adjusted so that the mass ratio of 15:85 was applied. A developer amount regulating blade was prepared in the same manner as in 1. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

<Example 7>
As a holder, an electrogalvanized layer is formed on both sides, and the secondary agglomerated silica and phosphorus with a secondary particle diameter of 100 nm are placed on a steel plate having a plating adhesion amount of 20 g / m ² and a plating layer thickness of about 2.7 μm Except for using 1.2 mm steel plate (Gincoat 21: trade name, manufactured by Nippon Steel Co., Ltd.) coated with a surface treatment solution adjusted so that the mass ratio of the acid salt was 15:85. A developer amount regulating blade was prepared in the same manner as in Example 1. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

<Comparative Example 1>
As a holder, a 1.2 mm steel sheet coated with a surface treatment solution adjusted so that the mass ratio of colloidal silica having a primary particle diameter of 20 nm and phosphate is 0.3: 99.7 (Jincoat 21: trade name) A developer amount regulating blade was prepared in the same manner as in Example 1 except that Shinnippon Steel Co., Ltd. was used. The same evaluation as in Example 1 was performed, and the results are shown in Table 2.

<Comparative example 2>
As a holder, a 1.2 mm steel plate coated with a surface treatment solution adjusted so that the mass ratio of colloidal silica having a primary particle diameter of 20 nm and phosphate is 50:50 (Gincoat 21: trade name, manufactured by Nippon Steel Co., Ltd.) A developer amount regulating blade was prepared in the same manner as in Example 1 except that Sakai Co., Ltd. was used. The same evaluation as in Example 1 was performed, and the results are shown in Table 2.

FIG. 3 is a schematic cross-sectional view of a holder used in the developer amount regulating blade of the present invention. FIG. 2 is a schematic cross-sectional view for explaining a developing device using the developer amount regulating blade of the present invention. It is a typical sectional view for explaining an electrophotographic device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface treatment layer 2 Zinc-type plating layer 3 Steel plate 30 Blade member 31 Support member 51 Photoconductor 52 Charging member 53 Electrostatic latent image 54 Developing device 55 Transfer means 56 Cleaning means 58 Fixing roller 61 Nozzle 62 Roll 63 Roll 64 For surface transfer Sheet 65 Blade member SD Orientation direction LD Longitudinal direction L Exposure means P Transfer material

Claims (4)

A developer amount regulating blade that has a support member and a blade member provided on the support member and regulates the amount of developer carried out of the developer container by the developer carrier;
The support member is formed by laminating a surface treatment layer surface containing a galvanized layer and silica on the steel plate surface in this order,
The developer amount regulating blade, wherein a content of the silica in the surface treatment layer is 0.5% by mass or more and 40% by mass or less.   The developer amount regulating blade according to claim 1, wherein the holder and the blade member are welded using a YAG laser. A method for manufacturing a developer amount regulating blade, comprising a support member and a blade member, for regulating the amount of developer carried out from a developer container by a developer carrier,
The support member is galvanized on a steel plate to form a plating layer;
Forming a surface treatment layer on the galvanized layer;
Processing the steel sheet into the shape of a support member to form a support member;
And then, welding the support member and the blade member,
The step of forming the surface treatment layer is a step of applying a surface treatment liquid in which silica is added to the inorganic rust preventive agent;
And a step of drying and solidifying the coated surface.   4. The method for producing a developer amount regulating blade according to claim 3, wherein the content of silica in the nonvolatile component contained in the surface treatment liquid is 0.5% by mass or more and 40% by mass or less.

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