JP2000172068A - Production of blade for electrophotographic device and blade body for electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a blade excellent in thickness precision at a low cost by pouring a blade material on a molding of a thermosetting resin, hardening it and cutting the resulting sheet. SOLUTION: A thermosetting resin is poured into a metallic mold 1 to form a thermosetting resin layer 8 on the inner surface of the metallic mold 1 and a poured elastic blade material layer 7 is formed on the thermosetting resin layer 8. The thermosetting resin preferably has heat resistance at >=150 deg.C and the thickness of the thermosetting resin layer 8 is preferably 0.5-3 mm. The elastic blade material is not particularly limited and polyurethane or silicone rubber may be used. The thermosetting resin cures while absorbing the deflection of the metallic, mold 1, the air side surface 8a of the thermosetting resin layer 8 is specular and the layer 8 has high deflection precision. The elastic blade material layer 7 therefore has good thickness precision that cannot be attained by the conventional method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a blade for an electrophotographic apparatus and a blade for an electrophotographic apparatus using the blade obtained by the method.

[0002]

2. Description of the Related Art A centrifugal molding method is a method in which a thermosetting material is poured into a heated cylindrical molding die rotating at a high speed to obtain a planar sheet. FIGS. 3A and 3B are diagrams schematically showing a centrifugal molding machine used for this centrifugal molding method, wherein FIG. 3A is a longitudinal sectional view, and FIG.
FIG. 4 is a cross-sectional view taken along a line A. FIG. 4 is a partially enlarged sectional view of a portion B when centrifugal molding is performed using the centrifugal molding machine shown in FIG.

[0003] As shown in FIG.
A mold 1 having a cylindrical shape with a bottom is installed inside a heat insulating chamber 2 in which the mold 1 is disposed, and the mold 1 is supported by a rotating shaft 5. At the time of molding, the mold 1 is heated to a predetermined temperature by the heater 3, then the mold 1 is rotated at a high speed, and the thermosetting material 6 is poured, as shown in FIG. Since the uniform thermosetting material layer 6 is formed on the inner surface 1a of the mold 1 by centrifugal force, a sheet of thermosetting material having a uniform thickness can be obtained.

According to this centrifugal molding method, the surface 6a which has been inside at the time of molding (hereinafter referred to as an air side surface) becomes a mirror-like smooth surface. In addition, since a sheet having a uniform thickness can be easily produced by this method, it is widely used in the field of molding of thermosetting materials. In addition,
Surface that was in contact with mold 1 (hereinafter referred to as mold contact surface) 6
The surface accuracy of b is affected by the roughness of the inner surface 1a of the mold.

[0005] With respect to the elastic blade used for the blade body for the electrophotographic apparatus, the centrifugal molding method easily makes a smooth surface required for a surface to be in sliding contact with a rotating body in the electrophotographic apparatus (hereinafter referred to as a used surface). It is possible to obtain a sheet of uniform thickness required for the blade body, and by changing the amount of material charged and the cut size of the obtained sheet, blade bodies of various dimensions can be easily obtained, The centrifugal molding method often produces an elastic blade because it has advantages such as being suitable for multi-kind production. However, the centrifugal molding method has the following problems.

[0006] In response to recent demands for miniaturization and high performance of OA equipment, low cost and high image quality of electrophotographic apparatuses have been developed. Along with this, in developing and cleaning devices, it has become necessary to increase the precision of the dimensional error range of the elastic blades. There is a problem that the accuracy depends on the runout accuracy of the mold of the machine. Here, the runout accuracy refers to the difference between the maximum value and the minimum value of the distance from the center axis of the mold to the inner surface of the mold when the mold rotates. The thickness accuracy refers to a difference between the maximum value and the minimum value of the sheet thickness for one molding.

[0007] Therefore, when a mold with poor runout accuracy is used, a sheet with poor thickness accuracy is of course produced, but when a molding die with good runout accuracy is used. However, when the sheet is manufactured, since the molding die is heated to 130 ° C. or higher, distortion due to heat occurs, and there is a problem that the runout accuracy during die cutting is not maintained.

Specifically, for example, even if a molding die precisely machined so that the deflection accuracy of the inner surface of the mold is 0.06 mm (at room temperature) is used, the sheet formed by centrifugal molding has a thickness accuracy. However, it is only about 0.30 mm at last.

As a method for preventing the heat distortion of the centrifugal mold in advance, there is a method called hot grinding in which the cutting of the mold is performed in accordance with the molding temperature. However, this method has a very high manufacturing cost. Not a realistic way.

FIG. 5 is a sectional view schematically showing an electrophotographic apparatus using a cleaning blade using an elastic blade obtained by a conventional centrifugal molding method and a toner thin film forming blade.

As shown in FIG. 5, the sheet formed by the centrifugal forming method is cut into a predetermined size to form elastic blades 32 and 42, and then is cut with an adhesive or a double-sided tape.
The cleaning blade body 30 and the toner thin film forming blade body 40 are adhered to the supports 31 and 41 made of a rigid body such as a metal.

In the elastic blades 32 and 42, the mold contact surfaces 32a and 42a are affected by the roughness of the inner surface of the mold and have poorer smoothness than the inner surface. Normally, the air side surfaces 32b and 42b are used as the surfaces to be brought into contact.

On the other hand, when the elastic blades 32, 42 are brought into contact with the rotating member on the other side, the elastic blades 32, 42 are attached so that the peeling force is not applied to the bonding portion between the elastic blades 32, 42 and the supports 31, 41. The surface of the elastic blade is opposite to the surface on which the elastic blade is used, that is, the mold contact surfaces 32a and 42a are used to bond the support 42 and the supports 31 and 41.

However, since a mold release agent is used in the mold, a mold release agent component such as a silicon compound, a fluorine compound, or wax adheres to the mold contact surface 6b (FIG. 4) of the sheet. Therefore, in order to obtain a sufficient adhesive strength, the mold contact surface 6b of the sheet has to be cleaned.

Further, in the conventional centrifugal molding method, foreign substances such as dust having a lower specific gravity than the thermosetting material and bubbles entrained at the time of casting are transferred to the inner surface of the sheet by centrifugal force to be hardened, and the blade is used. In some cases, the surface state of the air side surface 6a (FIG. 4), which is the surface, was determined to be defective.

[0016]

SUMMARY OF THE INVENTION In view of the above, the present invention does not require precise processing of the mold, does not require cleaning of the sheet after molding, and causes dust and the like to adhere to the blade use surface. A method for manufacturing a blade for an electrophotographic apparatus which can be manufactured at a low cost without causing a defect and having excellent thickness accuracy, and a blade for an electrophotographic apparatus manufactured by the manufacturing method It is an object of the present invention to provide a blade for an electrophotographic apparatus using the same.

[0017]

SUMMARY OF THE INVENTION A method of manufacturing a blade for an electrophotographic apparatus according to the present invention is a centrifugal molding method in which a thermosetting material is poured into the inside of a heated cylindrical mold while being rotated and cured. A method for producing a plate for an electrophotographic apparatus, comprising: pouring a thermosetting resin inside the mold, forming a molded body of the thermosetting resin inside the mold, The method is characterized in that a sheet is produced by pouring and curing the material of the electrophotographic device blade, and the obtained sheet is cut.

Further, in the blade body for an electrophotographic apparatus according to the present invention, an elastic blade having an edge portion on one main surface and the elastic blade are bonded to an end portion of the main surface opposite to the edge portion via an adhesive layer. An electrophotographic apparatus blade body comprising: a support member, wherein an electrophotographic apparatus blade obtained by the method for manufacturing an electrophotographic apparatus blade according to claim 1 is used as the elastic blade. It is a feature. Hereinafter, the present invention will be described in detail.

The method of manufacturing a blade for an electrophotographic apparatus according to the present invention is an electrophotographic apparatus using a centrifugal molding method in which a thermosetting material is poured into the inside of a heated cylindrical mold while being rotated and hardened. It is a method for producing a blade, in which a thermosetting resin is poured into the inside of the mold, and a molded body of the thermosetting resin is formed inside the mold,
Subsequently, a sheet is produced by pouring and curing the above-described electrophotographic device blade material (elastic blade material), and the obtained sheet is cut.

In the present invention, as described above, the sheet is produced by the centrifugal molding method. However, it is not necessary to use a new molding machine or a new mold for the centrifugal molding method. Such conventionally used ones can be used.

However, according to the present invention, after the thermosetting resin is poured into the inside of the mold and the molded body of the thermosetting resin is formed inside the mold, the elastic blade material is subsequently poured. A sheet is produced by curing. FIG. 1 is a cross-sectional view schematically showing a part of a mold (corresponding to a portion B in FIG. 3) when centrifugal molding is performed by the centrifugal molding method of the present invention.

As shown in FIG. 1, in the present invention, first, the thermosetting resin is poured into the mold 1, so that the thermosetting resin layer 8 is formed on the inner surface of the mold. Then, the poured elastic blade material layer 7 becomes the thermosetting resin layer 8.
Formed on

The thermosetting resin to be poured into the mold is not particularly limited as long as it is liquid at room temperature. However, in order to be able to form the elastic blade material layer 7 many times using the mold 1 on which the thermosetting resin layer 8 is formed, the thermosetting resin has a heat resistance of 150 ° C. or more. Are preferred. Examples of such a thermosetting resin include polyurethane rubber, phenol resin, polyimide resin, and silicone rubber. Among these, a silicone rubber which can form the elastic blade material layer 7 without using a release agent is preferable.

The thickness of the thermosetting resin layer 8 to be formed is 0.1 mm.
5 to 3 mm is preferred. When the thickness is less than 0.5 mm, the thickness of the thermosetting resin layer 8 is too small, so that the thermosetting resin layer 8 has no strength. When the thermosetting resin layer 8 is peeled from the mold, it cannot be completely peeled off. Since the heat of the mold cannot be transferred effectively, the formed elastic blade material layer 7
Adversely affect the characteristics of

The elastic blade material is not particularly restricted but includes, for example, polyurethane, silicone rubber, ethylene / propylene / diene copolymer (EPDM) and the like. Of these, polyurethane is preferred because it has less contamination of the mating member, has a small permanent set, and has excellent abrasion resistance. As the polyurethane, those obtained by a reaction between a polymer polyol and a diisocyanate are preferable.

Examples of the high molecular polyol include:
Polyethylene glycol, polypropylene glycol,
Polyoxyalkylene glycols such as polyoxytetramethylene glycol; polyether-type polyols of bisphenol A and glycerin ethylene oxide adduct; dibasic acids such as adipic acid, phthalic anhydride, isophthalic acid, maleic acid, fumaric acid and ethylene glycol ,
Propylene glycol, 1,4-butanediol, 1,
Polyester-type polyols obtained by a polymerization reaction with glycols such as 6-hexanediol and trimethylolpropane; polycaprolactone diol, polycarbonate diol and the like. The number average molecular weight of the high molecular polyol is preferably from 500 to 5,000, more preferably from 1,000 to 3,000. The above polymer polyols may be used alone or in combination of two or more.

Examples of the diisocyanate compound include tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and 1,4-cyclohexane diisocyanate. The diisocyanate compounds may be used alone or in combination of two or more.

Examples of the chain extender include low molecular weight diols such as ethylene glycol, 1,4-butanediol, diethylene glycol, 1,6-hexanediol and neopentyl glycol; diamines such as ethylenediamine, hexamethylenediamine and isophoronediamine And the like. Of these, low molecular weight diols are preferred. Further, if necessary, as a multifunctional component, trimethylolpropane, triethanolamine,
Glycerin and their ethylene oxide and propylene oxide adducts may be added.

According to the above-described method of the present invention, since a mirror-like surface is formed on the air side surface 8a of the thermosetting resin layer 8 which has been poured first, the resin of the elastic blade material layer 7 which has been poured subsequently. The contact surface 7b also has a mirror surface. It goes without saying that the air side surface 7a of the elastic blade material layer 7 has a mirror-like shape.

Therefore, conventionally, as shown in FIG. 5, the air side surfaces 32a, 32b of the elastic blades 32, 42 have to be used, but in the present invention, as shown in FIG. The use surfaces of the elastic blades 12, 22 can be the resin contact surfaces 12b, 22b. As a result, the air side surface 12 which is not affected by the mold release agent or the mold stain attached to the mold.
Since a and 22a can be used as bonding surfaces with the supports 11 and 21, there is no need to clean the bonding surface, and productivity can be increased. In addition, since the resin contact surfaces 12b and 22b in which surface defects are unlikely to occur can be used surfaces, surface defects are reduced and productivity is increased.

Further, if the thermosetting resin is poured into the mold without precision machining of the mold so that the deflection accuracy of the molding mold becomes good, the thermosetting resin becomes The thermosetting resin layer 8 is cured in a form absorbing the vibration, and the inside air side surface 8a has a mirror-like shape, and has a high vibration precision. As a result, it is possible to produce the elastic blade material layer 7 having good thickness accuracy that cannot be achieved by the conventional method.

The support member used for the electrophotographic apparatus blade body (cleaning blade body, toner thin film forming blade body, etc.) of the present invention is not particularly limited.
Rigid metals, elastic metals; plastics, ceramics and the like can be mentioned. Among these support members, a rigid metal is preferably used. The method of bonding the elastic blade and the support member is not particularly limited, and examples thereof include a bonding method using a polyamide-based or polyurethane-based hot melt adhesive, or an epoxy-based or phenol-based adhesive.

[0033]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Embodiment 1Formation of silicone rubber layer (thermosetting resin layer)  The molding die drum of the centrifugal molding machine having the configuration shown in FIG.
Diameter: 700mm, Depth: 500mm, deflection at room temperature
(Degree: 0.06 mm, rotational speed during molding: 800 rpm)
Heat to 160 ° C and use silicone
Commercially available TSE3032 containing loxane as the main component (Toshiba Silicon Corporation)
A mixture of a base material and a hardening agent of
Pour into drum and heat cure for 90 minutes.
A rubber layer (thermosetting resin layer) was formed. Cured silicone
The air side of the cone rubber is mirror-like, and the runout accuracy is
At 160 ° C., it was 0.01 mm.

The runout accuracy was measured by contacting a 1/100 dial gauge fixed to a strong base with the inner surface of the mold and slowly rotating the mold drum to measure the maximum and minimum values in the circumferential direction. The maximum value obtained by repeating the operation three times in the mold thrust direction was defined as the runout accuracy.

[0036]Formation of elastic blade material layer  Set the temperature of the mold to 140 ° C and set the elastic blade material
As MDI-PEA urethane prepolymer (Japan
Polyurethane, Mn: 2000, NCO: 6.3
%) And a curing agent (1,4-butanediol and trimethyi)
Mixture with a weight ratio of 3: 2 to roll propane)
Mixed at a ratio of H group equivalent / total NCO group equivalent = 0.9
After stirring, this viscous liquid forms a silicone rubber layer.
Poured into the mold. The number of revolutions during shaping is 80
It was 0 rpm. After heating and curing for 60 minutes,
Take out only the material layer and place it in an oven at 120 ° C.
For 12 hours, and consist of elastic blade material layer
A molded sheet was obtained.

Next, the obtained molded sheet was cut into a predetermined size to produce an elastic blade, and the following evaluation was performed. As a result, the thickness accuracy was as good as 0.045 mm. Regarding the surface state of the elastic blade, four defects were observed on the air side surface, but the resin contact surface was a mirror surface state, and no defect was found.
In the elastic blade obtained in this embodiment, since the resin contact surface is used as a surface to be used, there is no surface defect when used as a product.

[0038]Evaluation method  (1) Thickness accuracy The total thickness of the elastic blade obtained from one molded sheet
Is measured with a thickness gauge with a minimum scale of 1 / 1000mm
Then, the difference between the maximum value and the minimum value was defined as the thickness accuracy.

(2) Surface Condition of Elastic Blade The surface of the obtained elastic blade was visually inspected for defects such as bubbles and foreign matter.

Comparative Example 1Formation of elastic blade material layer  Using the same molding machine and mold as in Example 1, the temperature of the molding
After setting the degree to 140 ° C., as a mold release agent
Uses a very small amount of fluorine-silicon compatible release agent
Then, the release agent was wiped and spread on the inner surface of the mold. Next, elastic
As the blade material, the same urethane as in Example 1
Use prepolymer and hardener, same rotation speed and same
Example 1 after molding for curing time and removing the molded sheet
Secondary crosslinking was carried out under the same conditions as described above. After that, the obtained
After cutting the shaped sheet to make an elastic blade,
Evaluation was performed in the same manner as in Example 1. In addition, the deflection of the molding die
The accuracy is 0.24 mm when heated to 140 ° C.
Was.

As a result, the thickness accuracy was 0.252 mm, which was much higher than that of the embodiment. Further, since the processing traces of the mold molding were transferred to the mold contact surface, it could not be used for the plate using surface. There were five surface defects of the elastic blade for one molding, and the elastic blade having these surface defects had poor surface properties and could not be used as a product.

[0042]

According to the method of manufacturing a blade for an electrophotographic apparatus of the present invention, there is no need to perform precision processing on the mold, no need to wash the sheet after molding, and to remove dust and the like on the blade use surface. A blade for an electrophotographic apparatus having excellent thickness accuracy can be manufactured at low cost without causing defects due to adhesion. Further, according to the blade for an electrophotographic apparatus of the present invention, an inexpensive blade for an electrophotographic apparatus having excellent thickness accuracy can be provided.

[Brief description of the drawings]

FIG. 1 is a partially enlarged cross-sectional view schematically showing the inside of a mold when molding is performed using a centrifugal molding method in a method of manufacturing a blade for an electrophotographic apparatus of the present invention.

FIG. 2 is a cross-sectional view schematically showing an example of an electrophotographic apparatus using the blade for an electrophotographic apparatus of the present invention.

FIGS. 3A and 3B are diagrams schematically showing a centrifugal molding machine used for the centrifugal molding method, wherein FIG. 3A is a longitudinal sectional view, and FIG. 3B is a sectional view taken along line AA in FIG.

FIG. 4 is a partially enlarged cross-sectional view schematically showing the inside of a mold when molding is performed using a centrifugal molding method in a conventional method for manufacturing a blade for an electrophotographic apparatus.

FIG. 5 is a cross-sectional view schematically showing an example of an electrophotographic apparatus using a conventional electrophotographic apparatus blade.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold 1a Inner surface 2 Heat insulation chamber 3 Heater 7 Elastic blade material layer 7a Air side surface 7b Resin contact surface 8 Thermosetting resin layer 8a Air side surface 10, 30 Cleaning blade body 11, 31 Support body 12, 32 Elastic blade 12a Air surface Side 12b Resin contact surface 20, 40 Toner thin film forming blade 21, 41 Support 22, 42 Elastic blade 22a Air side 22b Resin contact surface 32a, 42a Mold contact surface 32b, 42b Air side

Continued on the front page (72) Inventor Yoshinori Fujiwara 3-2-15 Meiwadori, Hyogo-ku, Kobe Bando Chemical Co., Ltd. F-term (reference) 2H034 BF01 2H077 AD13 AD17 FA22 4F205 AA33 AA36 AA42 AA45 AB03 AG01 AH33 AM32 GA02 GB01 GC04 GE02 GE06 GE27 GF01 GN01 GN13 GN28 GN29 GW06 GW23

Claims (3)

[Claims] 1. A method of manufacturing a plate for an electrophotographic apparatus using a centrifugal molding method in which a thermosetting material is poured into a heated cylindrical mold while being rotated, and is cured. Pour the thermosetting resin into the inside of the mold, after forming a molded body of the thermosetting resin inside the mold, subsequently, pour the material of the electrophotographic device blade, and cure by curing the sheet A method for producing a blade for an electrophotographic apparatus, comprising producing and cutting an obtained sheet. 2. An electrophotographic blade comprising: an elastic blade having an edge on one main surface; and a support having the elastic blade bonded to an end of the main surface opposite to the edge via an adhesive layer. Body, as the elastic blade,
A blade for an electrophotographic apparatus, wherein the blade for an electrophotographic apparatus obtained by the method for manufacturing a blade for an electrophotographic apparatus according to claim 1 is used. 3. When a sheet is produced by a centrifugal molding method,
3. The electrophotographic apparatus blade according to claim 2, wherein an edge portion is formed on a side of the surface which has been in contact with the thermosetting resin.