JP2007264240A - Developer amount regulating blade and developing device equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer amount regulating blade easily manufactured and easily restraining an image defect such as stripes and irregularity. <P>SOLUTION: The developer amount regulating blade 13 is constituted by laminating a blade member 10 and a supporting member 12 so as to form a layer where their entire surfaces are just superposed while keeping the same shape each other, and the surface of the blade member 10 at a leading end is fixed so as to abut on a developer carrier 15. The leading end is folded to the rotating direction side of the developer carrier 15 all over the width. A linear part extended from a fixed point 16 to the leading end side is inclined so as to turn to an opposite direction side to the rotating direction of the developer carrier 15 toward the leading end side from a perpendicular to the surface of the developer carrier 15 at the abutting part on the developer carrier 15. Then, an angle θ2 formed by the perpendicular to the surface of the developer carrier 15 at the abutting part with the linear part extended from the fixed point 16 to the leading end side is set to be larger than 0° and smaller than 80°. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a developer amount regulating blade for regulating the amount of developer used to develop and visualize an electrostatic latent image formed on an image carrier such as an electrophotographic apparatus, and the developer amount regulation. The present invention relates to a developing device equipped with a blade.

  In general, a developing device carries a developer (also referred to as toner) on a developer carrier (also referred to as a developing sleeve or a developing roller) to form an electrostatic latent image on an image carrier such as an electrophotographic photosensitive member. It has the structure which supplies on a surface. In the developing device, a developer amount regulating blade is fixed so as to contact the surface of the developer carrying member. The developer is regulated in the amount of adhesion on the developer carrier by the developer amount regulating blade, and the developer carried on the surface of the developer carrier is made into a thin film.

  The developer amount regulating blade is generally formed of a rubber plate, a metallic thin plate, a resin plate, and a laminate thereof, and a blade member pressed against the developer carrier, and supports the blade member at a predetermined position. It consists of a support member. The surface of the blade member that is in pressure contact with the developer carrier has a function of controlling the triboelectric charge of the developer, and is also referred to as a charge control surface. Further, the surface layer near the charge control surface may be referred to as a charge control layer.

  Examples of the blade member used for the negative toner include a blade member made of urethane rubber, urethane resin, polyamide elastomer, or the like. Further, as the developer amount regulating blade used for the positive toner, a blade obtained by laminating a charge imparting layer such as silicone rubber with charge control on a thin metal plate is used.

  Furthermore, for the non-magnetic toner used for forming a color image, since the toner itself does not have magnetism, a high triboelectric charge must be given to the toner to form a thin film on the developing sleeve or developing roller. In this case, examples of the material used for the charge control layer of the blade member include urethane rubber, polyamide resin, polyamide elastomer, silicone rubber, and silicone resin, and the charge control surface is finished with high surface accuracy.

  In recent years, high-quality and full-color developing devices applied to the electrophotographic process use toner with fine particles, so that it is required to more uniformly press the toner to the developing sleeve and the developing roller. ing.

Patent Document 1 discloses a configuration of a developer amount regulating blade in which a blade member, an adhesive, and a support member are laminated so as to form a layer having substantially the same shape and the entire surface just overlapping each other. ing. Furthermore, the blade tip shape of the developer amount regulating blade is formed, the first inclined surface is formed at the edge formed by the sliding surface and the end surface, and the edge formed by the bonding surface and the end surface of the blade member with the support member Patent Documents 2 and 3 disclose a blade having a shape in which a second slope is provided. According to such a blade configuration, color toner particles are fused to the charge imparting surface of the developer amount regulating blade even in a color copying machine or a color laser beam printer that has been improved in speed and durability. Can be effectively suppressed.
JP 2002-372858 A JP 2002-372854 A JP 2002-372855 A

  However, when the blade tip shape disclosed in Patent Documents 2 and 3 is adopted, it is difficult to process into this shape and the quality of the blade tip shape tends to vary, so further technical studies are desired. It is rare. In addition, while avoiding such difficulties, it is possible to prevent the color toner particles from being fused to the charge imparting surface of the developer amount regulating blade even when the fine particle toner is used. It has been demanded. Furthermore, it is required to make it possible to more uniformly press the toner to the developing sleeve and the developing roller.

  The present invention has been made in view of the above-described state of the art, and a developer, particularly color toner particles, are provided on the surface to which the charge is applied while the developer amount regulating blade can be easily manufactured. It aims at enabling it to control that it fuses. In addition, the developer amount regulating blade smoothes the surface of the charge imparting layer and accurately controls the contact pressure to achieve an appropriate pressure on the toner particles, so that the toner on the developing sleeve and the developing roller The pressure bonding can be made more uniform. Then, image defects such as streaks and unevenness are suppressed.

  Another object of the present invention is to provide a developing device that includes such a developer amount regulating blade and can suppress image defects such as streaks and unevenness due to the developer.

  It is an object of the present invention to have a configuration in which at least a blade member and a support member that regulate the amount of developer carried out of a developer carrier from a developer container are stacked so as to form a layer having the same shape and overlapping each other. In the developer amount regulating blade, the tip of the blade member is fixed so that the surface of the blade member at the tip is in contact with the developer carrier and regulates the amount of the developer carried out from the developer container by the developer carrier. Is bent to the rotation direction side of the developer carrier over the entire width, and the linear portion extending from the fixed point toward the tip end side of the developer carrier is a contact portion with the developer carrier. Inclined so as to face the direction opposite to the rotation direction of the developer carrier from the surface normal to the tip side, and the normal of the surface of the developer carrier at the contact portion, and the linear portion The angle to make It is achieved by the developer amount regulation blade which was characterized by less than greater 80 degrees than degrees.

  In the developer amount regulating blade, the bending angle of the tip portion is in the range of 10 ° to 70 °.

  The developer amount regulating blade is characterized in that the radius of curvature of the outer surface of the bent portion of the tip is in the range of 0.1 mm to 2.0 mm.

  In the developer amount regulating blade, a distance between the bent position and the end of the tip portion is in a range of 0.2 mm to 2 mm.

  The developer amount regulating blade has a ten-point average roughness (Rz) of 0.1 μm or more and 3.5 μm or less as a surface roughness of the contact portion.

  In the developer amount regulating blade, the blade member is made of a material containing at least one selected from the group consisting of polyamide, polyamide elastomer, polyester, polyester elastomer, and polyester terephthalate. .

  Further, in a developing device used for developing and visualizing an electrostatic latent image formed on an image carrier such as an electrophotographic apparatus, the developer amount regulating blade described in any of the above is mounted. It is characterized by.

  When the developer amount regulating blade of the present invention is used, the charge imparting layer surface of the blade member is smoothed and the contact pressure with the developer carrier is accurately controlled to achieve an appropriate pressure on the toner particles. can do. As a result, image defects such as streaks and unevenness can be suppressed. Further, it is possible to uniformly regulate the amount of developer on the developer carrying member, to uniformly charge the developer particles, and to fuse the toner particles to the surface of the charge imparting layer of the developer amount regulating blade. Can be suppressed.

  Furthermore, the developer amount regulating blade of the present invention can be easily manufactured while ensuring necessary accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, an outline of the overall configuration of the developing device will be described with reference to FIG. FIG. 4 shows an example of the configuration of the developing device, and the present invention is not limited thereto. Examples of the electrophotographic apparatus that can use the developing device of the present invention include a copying machine, a laser beam printer, an EL printer (LED printer), and an electrophotographic application apparatus such as an electrophotographic plate making system.

  The developing device shown in FIG. 4 has, as an example, a developer container 14 that contains a one-component developer 46. An elastic roller 45 and a developer carrier 15 are rotatably provided in the developer container 14. The elastic roller 45 and the developer carrier 15 are in pressure contact with each other, and a part of the developer carrier 15 protrudes from the side surface of the developer container 14. Although not described in detail, this developing device uses an image carrier on which the electrostatic latent image is formed on the surface of the developer carrier 15 protruding from the developer container 14, such as the electrophotographic photosensitive member shown in the figure. The distance to the surface of the body 41 can be changed.

  In this developing device, the developer 46 in the developer container 14 is pressed against the developer carrier 15 by an elastic roller 45 that rotates in the c direction. The pressed developer is carried out to the electrophotographic photosensitive member 41 that rotates in the direction a by the rotation of the developer carrier 15 in the direction b.

  In such a mechanism, the developer amount regulating blade 13 is in contact with the developer carrier 15. As a result, the amount of the developer 46 carried out is regulated to form a thin film of the developer 46, and at the same time, a predetermined triboelectric charge (also called tribo) is applied to the developer 46 at the contact portion.

  Next, the details of the configuration of the developer amount regulating blade 13 of this embodiment will be described with reference to FIG.

  The developer amount regulating blade 13 of the present invention is configured by laminating at least the blade member 10 and the support member 12 so as to form a layer having substantially the same shape and overlapping the entire surface. The developer amount regulating blade 13 is configured so that the surface of the blade member 10 at the blade tip portion (the end portion on the contact portion side of the developer amount regulating blade 13) abuts against the developer carrier 15 with a predetermined pressure contact force F. It is fixed to. The blade tip is bent over the entire width toward the rotation direction b of the developer carrier 15.

  The straight line portion of the developer amount regulating blade 13 extending from the fixed point (end of the fixed portion on the blade tip side) 16 toward the tip side is the contact portion of the developer carrier 15. It is inclined from the surface normal to the tip side toward the direction opposite to the rotation direction b of the developer carrier. The angle θ2 formed between the perpendicular of the surface of the developer carrier 15 and the linear portion at the contact portion between the developer amount regulating blade 13 and the developer carrier 15 is greater than 0 degree and greater than 80 degrees. small.

  FIG. 1 shows a developer amount regulating blade 13 according to the present embodiment as an example of the present invention. In this example, the developer amount regulating blade 13 includes, in addition to the support member 12 and the blade member 10, It has the adhesive member 11 which joins both.

  The blade member 10 is made of a material having good toner chargeability. Examples of the material forming the blade member 10 include polyamide, polyamide elastomer, polyester, polyester elastomer, and polyester terephthalate. These can be used alone or in combination of two or more. In addition, an additive such as a conductive material can be added to the constituent material of the blade member 10 in order to form a desired charge imparting layer that achieves a predetermined charging performance or the like.

  The thickness of the blade member 10 is preferably 0.01 mm or more and 0.3 mm or less. When the thickness of the blade member 10 is less than 0.01 mm, the durability against wear due to friction with the developer carrying member decreases. On the other hand, when the thickness of the blade member is greater than 0.3 mm, it is difficult to obtain a stable contact pressure.

  The support member 12 is preferably made of a material such as a metal flat plate or a resin flat plate. Specific examples include metal flat plates such as stainless steel plates, phosphor bronze plates, and aluminum plates, and resin flat plates such as polyethylene terephthalate, acrylic, polyethylene, and polyester. The thickness of the support member 12 is preferably 0.05 mm or greater and 0.15 mm or less. If the thickness of the support member 12 is less than 0.05 mm, an appropriate contact pressure cannot be obtained, and a necessary pressure cannot be applied to the developer particles. On the other hand, if the thickness of the support member 12 is 0.15 mm or less, the developer amount regulating blade 13 easily follows the developer carrier 15 due to the spring property of the support member 12, which It is effective to apply the necessary pressure to the surface.

  The adhesive member 11 has a function of joining the support member 12 and the blade member 10 together. Examples of the adhesive material for forming the adhesive member 11 include adhesive materials such as polyurethane hot melt, polyester hot melt, ethylene vinyl alcohol (EVA) hot melt, and polyamide hot melt. be able to.

  If the angle θ2 is 0 degrees or less, sufficient developer cannot be taken into the developer carrier 15. Note that the negative value of the angle θ2 indicates that the straight line portion of the developer amount regulating blade 13 extending from the fixed point 16 is directed toward the front end portion from the perpendicular of the surface of the developer carrier 15 at the contact portion. The case where the developer carrier is inclined to the rotation direction b side is shown.

  The bending angle θ1 of the blade tip portion (the angle formed between the portion closer to the tip than the bent portion and the portion on the fixed point 16 side) is preferably in the range of 10 ° to 70 °. When the bending angle is less than 10 °, the spring property of the support member 12 becomes too strong, and sufficient developer cannot be taken into the developer carrier 15. When the angle is 90 ° or more, the bent tip portion comes into contact with the toner once taken on the developer carrying member 15, so that streaks and unevenness occur in the toner layer on the developer carrying member 15. End up.

  The bending radius R of the blade tip portion (the radius of curvature of the outer surface of the bent portion) is preferably in the range of 0.1 mm to 2.0 mm. When the bending radius R of the blade tip portion is smaller than 0.1 mm, the total blade thickness for obtaining an appropriate contact pressure cannot be obtained. If the bending radius R of the blade tip is larger than 2.0 mm, it becomes difficult to uniformly regulate the developer amount on the developer carrier 15.

  The distance L from the blade edge to the bending position of the blade tip is preferably in the range of 0.2 mm to 2 mm. If the distance L is less than 0.2 mm, the bent shape cannot be formed satisfactorily, and the toner cannot be uniformly coated on the developer carrier 15. On the other hand, if it is larger than 2 mm, it becomes difficult to regulate the amount of toner on the developer carrier 15.

  The surface roughness of the contact portion of the developer amount regulating blade 13 is preferably in the range of 0.1 μm or more and 3.5 μm or less in terms of 10-point average roughness (Rz). When the surface roughness is smaller than 0.1 μm in terms of 10-point average roughness (Rz), the influence of minute scratches and irregularities on the surface of the blade member 10 becomes conspicuous on the image. If the surface roughness is smaller than 3.5 μm in terms of 10-point average roughness (Rz), streaks or unevenness occurs in the developer layer on the developer carrying member 15 and the amount of developer cannot be regulated uniformly.

  Next, an example manufacturing method of the developer amount regulating blade of the present invention will be described according to the manufacturing process.

  As shown in FIG. 2, first, a sheet to be coated 24 (functioning as a surface transfer sheet and a protective sheet) is placed on a roll coater. Then, the blade member composition 25 is extruded from the extruder 21 onto the coated sheet 24, and the gap between the roll 22 and the roll 23 arranged close to each other with a predetermined gap is passed along with the coated sheet 24. As the blade member composition 25, one prepared from any of polyamide, polyamide elastomer, polyester, polyester elastomer, polyester terephthalate and the like can be used. By drying and solidifying the blade member composition 25, a blade member sheet in which a blade member layer 31 (see FIG. 3) having a predetermined thickness is formed on the coated sheet 24 is formed. The blade member sheet is wound up so that the coated sheet 24 faces outside.

  In this blade member sheet, the blade member layer 31 becomes the blade member 10 through a subsequent process, and the surface in contact with the coated sheet 24 becomes the contact surface with the developer carrier 15. As described above, the blade member composition 25 is extruded onto the coating sheet 24 in a molten state, and is applied and solidified. As a result, the surface of the blade member layer 31 formed as a coating solidified film from the blade member composition 25 in contact with the coated sheet 24 has a very smooth surface as the surface transfer sheet of the coated sheet 24. Transcribed. An appropriate value of the surface roughness of the very smooth surface of the coated sheet 24 as a surface transfer sheet is appropriately determined in relation to the developer particle diameter.

  FIG. 3 schematically shows an example of a laminated body forming process in which the blade member sheet is bonded to the support member 33 to form a laminated body.

  Adhesion between the blade member sheet and the support member 33 can be continuously performed by the apparatus shown in FIG. That is, a blade member sheet composed of the blade member layer 31 and the sheet to be coated 24 is supplied to the roll 35 through the roll 36, and at this time, an adhesive is applied to the surface of the blade member layer 31 using the spray 34. Thereafter, while supplying the support member 33 from the roll 37, the support member 33 and the blade member sheet are laminated, supplied to the nip between the rolls 35 and 37, and pressed to form a laminate. The obtained laminate is wound up on a roll 38. After the blade member sheet and the support member 33 are bonded together, a treatment such as heating may be performed in order to realize stronger adhesion.

  The laminated body thus obtained is made into a predetermined length by press cutting, wire cutting or the like, and then the blade tip is bent by an L bending process or a V bending process using a press to obtain a predetermined shape as described above. obtain. Finally, the coated sheet 24 is peeled off to complete the developer amount regulating blade 13.

  As described above, the developer amount regulating blade 13 of the present embodiment can be relatively easily manufactured while ensuring necessary accuracy.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited to a following example.

(Examples 1-7)
As a material for forming the blade member, a polyamide elastomer having a Shore D hardness of 40 ° (trade name: Daiamide E40, manufactured by Daicel Degussa) specified in JIS D 6253 was selected.

  In order to form a blade member, this material was melted at 200 ° C. and extruded onto a coated sheet (manufactured by Toyobo Co., Ltd., trade name: ester film) using a T-die extrusion molding machine (Pura Giken Co., Ltd.). And it nipped with the pressure of 0.4 Mpa with the roll heated at 40 degreeC, it extruded, sticking both together, and solidified, and the blade member sheet | seat was formed.

  Next, a phosphor bronze sheet (manufactured by Harada Shindohsho Co., Ltd.) having a thickness of 0.12 mm was used as a support member, and was bonded to the blade member sheet to form a laminate. At this time, an adhesive member layer made of Toyo Morton Adcoat AD-76P1 (trade name), which is an adhesive material, was provided between the blade member layer and the phosphor bronze sheet. For laminating, a laminating machine (manufactured by Okazaki Kikai Co., Ltd.) was used, and nipping was performed by a roll heated to 80 ° C. at a pressure of 0.2 MPa.

  The obtained laminate was press-cut to a predetermined blade size, and then the blade tip was bent by V-bending. Thereby, the bending angle, the bending radius, and the bending position were as shown in Table 1, and finally the coated sheet was peeled off to obtain the developer amount regulating blade of the sample of each example.

  The length of the developer amount regulating blade in the longitudinal direction was 200 mm, and the width was 23 mm. Further, the total thickness of the obtained developer amount regulating blade is 0.16 mm, including the blade member thickness of 0.03 mm, the adhesive thickness of 0.01 mm, and the support member thickness of 0.12 mm. It was. The ten-point average roughness (Rzjis) of the surface of the blade member layer was 0.3 μm.

Next, the obtained developer amount regulating blade was replaced with a developer amount regulating blade in a developing device for a laser beam printer (trade name: Satera, manufactured by Canon) to obtain a developing device of each example. At this time, the normal of the surface of the developer carrying member at the contact point between the developer amount regulating blade and the developer carrying member and the straight portion of the developer amount regulating blade extending from the fixed point toward the tip end side. The angle θ2 was set as shown in Table 1. Then, a solid black image was output, and the presence or absence of streaks and unevenness in the output image was confirmed. The results are shown in Table 1 evaluated according to the following criteria.
○: None △: Almost none ×: Available (Example 8)
In this example, as in Examples 1 to 7, a developer amount regulating blade was prepared, and incorporated in a laser beam printer, and an output image was evaluated. At this time, a Teijin DuPont film (trade name: Teijin matte film) was used as the coated sheet, and as a result, the 10-point average roughness (Rzjis) of the surface of the blade member layer was 3.2 μm. Further, θ2, bending angle, bending radius, and bending position were set according to the conditions shown in Table 1.

(Comparative Example 1)
In this comparative example, a developer amount regulating blade was produced in the same manner as in Examples 1 to 7 except that V bending was omitted, and the blade was incorporated into a laser beam printer to evaluate the output image. The ten-point average roughness (Rzjis) of the surface of the blade member layer was 0.3 μm, as in Examples 1-7. θ2 was set to 40 °.

(Comparative Example 2)
A phosphor bronze sheet (manufactured by Harada Shindohsho Co., Ltd.) was press-cut into a predetermined blade size to obtain a developer amount regulating blade of this comparative example. The length of the developer amount regulating blade in the longitudinal direction was 200 mm, and the width was 23 mm. The ten-point average roughness (Rzjis) of the surface of the obtained developer amount regulating blade was 0.7 μm.

  Next, as in the example, a developer amount regulating blade was incorporated into a laser beam printer, and an output image was evaluated. At this time, θ2 was set to 40 °.

(Comparative Examples 3-4)
In this comparative example, similarly to Examples 1 to 7, a developer amount regulating blade was produced, and incorporated in a laser beam printer, and an output image was evaluated. At this time, as shown in Table 1, θ2 was set outside the scope of the present invention. The bending angle, bending radius, and bending position were set according to the conditions shown in Table 1.

  The above evaluation results are summarized in Table 1.

  From Table 1, it can be seen that image defects such as streaks and unevenness can be suppressed by using the developer amount regulating blade of each example according to the present invention. According to the developer amount regulating blade of the present invention, the charge imparting surface is made smooth, and the contact pressure with the developer carrier is accurately controlled to achieve an appropriate pressure on the toner particles. It means you can do it. That is, it is possible to uniformly regulate the developer amount on the developer carrying member and to uniformly charge the developer particles, and to fuse the toner particles to the surface of the charge imparting layer of the developer amount regulating blade. Can be suppressed. As a result, good image output is possible.

FIG. 3 is a schematic cross-sectional view illustrating a developer amount regulating blade according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view for explaining the method for manufacturing the developer amount regulating blade of the embodiment of the present invention. FIG. 5 is a schematic cross-sectional view for explaining the method for manufacturing the developer amount regulating blade of the embodiment of the present invention. 1 is a schematic cross-sectional view illustrating a developing device according to an embodiment of the present invention.

Explanation of symbols

F Pressing force θ ₁ Bending angle θ ₂ Angle formed between the line connecting the rotation center of the developer carrier at the bending point of the developer amount regulating blade and the pressing direction of the developer amount regulating blade R Bending radius L Bending position 10 Blade Member 11 Adhesive member 12 Support member 13 Developer amount regulating blade 14 Developer container 15 Developer carrier 16 Fixed point 21 Nozzle 22 Roll 23 Roll 24 Surface transfer sheet 25 Raw material 31 Blade member 32 Surface transfer sheet 33 Support member 34 Spray 35 roll 36 roll 37 roll 38 roll 41 electrophotographic photosensitive member (image carrier)
42 Developer container 43 Developer carrier (developing sleeve, developing roller)
44 Developer amount regulating blade 45 Elastic roller 46 Developer (toner)

Claims (7)

At least the blade member and the support member that regulate the amount of the developer carried out of the developer container from the developer container are laminated so as to form a layer having the same shape and the entire surface overlapping each other, and In the developer amount regulating blade that is fixed so that the surface of the blade member is in contact with the developer carrier and regulates the amount of the developer carried out from the developer container by the developer carrier,
The tip is bent over the entire width to the rotation direction side of the developer carrier,
The developer has a linear portion extending from the fixed point toward the tip end side toward the tip end side from a perpendicular to the surface of the developer carrier at the contact portion with the developer carrier. Inclined so as to face the direction opposite to the rotation direction of the carrier, and an angle formed by a perpendicular to the surface of the developer carrier and the linear portion at the contact portion is greater than 0 degree and less than 80 degrees A developer amount regulating blade characterized by that.   The developer amount regulating blade according to claim 1, wherein a bending angle of the tip portion is in a range of 10 ° to 70 °.   3. The developer amount regulating blade according to claim 1, wherein a radius of curvature of an outer side surface of the bent portion of the tip portion is in a range of 0.1 mm to 2.0 mm.   4. The developer amount regulating blade according to claim 1, wherein a distance between the bent position and the end of the tip end part is in a range of 0.2 mm to 2 mm. 5. .   5. The developer amount regulation according to claim 1, wherein a surface roughness of the abutting portion is not less than 0.1 μm and not more than 3.5 μm in terms of ten-point average roughness (Rz). blade.   6. The blade member according to claim 1, wherein the blade member is made of a material including at least one selected from the group consisting of polyamide, polyamide elastomer, polyester, polyester elastomer, and polyester terephthalate. The developer amount regulating blade according to Item. In a developing device used for developing and visualizing an electrostatic latent image formed on an image carrier,
A developing device comprising the developer amount regulating blade according to any one of claims 1 to 6.

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