JP2008094022A - Manufacturing method for elastomer molded body, and blade member for electronic photographing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for an elastomer molded body by which the molded body can easily be peeled and released from a molding die without generating torn or the like even if the molded body has a thin film form after inputting and hardening an elastomer raw material, and to provide a blade member for an electronic photographing apparatus using the elastomer molded body. <P>SOLUTION: In this manufacturing method, the elastomer raw material is fed into a molding die having a plurality of surfaces to manufacture the molded body. In the manufacturing method, the molding die for which different mold release treatments are applied to surfaces of the plurality of surfaces is used. The molding die is preferably a centrifugal molding die, and has a cylindrical inner peripheral surface, and a bottom surface or an edge peripheral surface which is formed at the end of the cylindrical inner peripheral surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing an elastomer molded body and a blade member for an electrophotographic apparatus produced by using this method. More specifically, the present invention relates to a method for producing an elastomer molded article suitable for producing an elastomer molded article having a thin and uniform thickness and a blade member for an electrophotographic apparatus.

  In an image forming apparatus of an electrophotographic apparatus represented by a copying machine, a printer, a facsimile machine, etc., a toner as a developer is adhered to an electrostatic latent image obtained by exposing a uniformly charged photoreceptor. Is transferred to a transfer material such as paper to form an image. In the image forming apparatus, in order to keep the amount of toner supplied to the photosensitive member constant, a developing blade that forms a thin toner film with a constant thickness on the developing roller, and the toner on the electrostatic latent image of the photosensitive member are transferred to a recording material. Thereafter, a blade such as a cleaning blade for removing residual toner from the surface of the photoreceptor is provided. Such a blade has a blade member formed of an elastic body, and is installed in the electrophotographic apparatus via a hard support made of metal or the like that joins the blade member. Since the blade member has a function of uniformly forming a developer of about 10 μm on the developing roller and removing it from the photosensitive member, the thickness non-uniformity that causes variation in contact pressure is an image to be formed. Cause a fatal defect. For this reason, the blade member is required to have a uniform thickness with high accuracy.

  As a method for producing such a blade member, a general method is a method in which an elastomer raw material is formed into a sheet by centrifugal molding and cut. The method of obtaining a sheet by centrifugal molding is a method in which a plastic elastomer raw material is put into a drum-shaped centrifugal mold, and a thin sheet having a uniform thickness is formed on the inner peripheral surface of the mold by centrifugal force. The obtained sheet can be applied to various members.

  However, the molding of elastomeric members by centrifugal molding has some drawbacks.

  First of all, when a material having adhesive properties such as thermosetting polyurethane is selected as the elastomer raw material, it is very difficult to peel and demold the molded body from the mold after centrifugal molding. In order to facilitate demolding, a silicone oil-based or fluorine-based release agent diluted with a solvent is generally applied to the inner peripheral surface of a centrifugal mold. However, when the oil component of the release agent is excessive, the molded product moves to a molded product, which may cause fogging in the molded product. Furthermore, the migration of the oil component may adversely affect the adhesiveness of the molded body. Further, the detachability from the mold in the molded body varies due to variations in the amount of release agent applied. When the detachability is poor, tearing occurs at the time of taking out, and not only the production number decreases, but also the production efficiency decreases, for example, the mold is cleaned again. There are many factors related to mold release agents and mold release methods, and there are few academic knowledge, and selection of these mold release agents, optimization of the dilution rate, application amount, application frequency, cleaning frequency, etc. are experienced. At present, there is no choice but to rely on.

  The second is that it is not easy to ensure a certain thickness. Centrifugal molding is effective for obtaining thin cylindrical dimensions and for producing thin, large-area, uniform sheet-like products, but strict precision control of the equipment is required to always obtain uniform thickness dimensions. become. Centrifugal molds are equipped with a rotating cylindrical mold, which is charged with a desired amount of material, formed into a thin film on the inner peripheral surface of the cylinder by the rotating centrifugal force, and heated and cured to form. Although the body is obtained, the deflection of the inner peripheral surface is reflected on the molded body as it is, and the thickness thereof varies. Furthermore, if there is a scratch or the like on the inner peripheral surface, it is also transferred to the product as it is. In other words, centrifugal molds are required to have high horizontal accuracy of the rotating shaft, accuracy of the inner peripheral surface of the cylinder, and smoothness of the inner peripheral surface, and it is required to maintain high mechanical accuracy at all times. It is a problem.

  Third, there is a need in the field of electrophotography. Recent technological advances in the electrophotographic field have revealed that, in a developer amount regulating blade, having a specific surface roughness on the surface in contact with the developing roller can achieve higher functionality. The amount of developer formed on the developing roller is uniformly controlled by the developer amount regulating blade to which a specific surface roughness is imparted, and a high-quality image without density unevenness can be obtained. The sheet obtained by the centrifugal mold is not obtained as having such a surface roughness, and it is difficult to apply the sheet as it is to the developer amount regulating blade.

  In response to the first problem, a thermosetting material such as liquid silicone rubber is poured into the inner peripheral surface of the mold to which the raw material is charged, and this is cured to provide a silicone layer. A method for avoiding the use of a mold has been reported (Patent Document 1).

  For the second problem, the liquid material is put into a centrifugal mold and cured, and a layer is provided in the centrifugal mold. It has been reported that a thin molded article is obtained (Patent Document 2).

  As for the third problem, it has been clarified that a good image can be obtained by performing a certain roughening process on the surface of the portion in contact with the developer carrying member with respect to the developer amount regulating blade ( Patent Document 3). Furthermore, since it takes an enormous amount of time to perform surface roughening by polishing or the like for each individual member, a method of roughening the surface at once by centrifugal molding has been proposed. For example, the release layer provided on the inner peripheral surface of the centrifugal mold is subjected to a roughening treatment, making it easy to peel and remove the molded body from the centrifugal mold, and at the same time roughening the release layer on the surface of the molded body. This is a method for efficiently transferring the surface and obtaining a highly functional electrophotographic member (Patent Document 4).

As described above, a method for molding an elastomer using a centrifugal mold has been reported, but further molding that makes it easier to peel and remove the molded body and suppress tearing of the molded body when taken out from the mold. There is a need for improved methods.
JP 2000-172048 JP 2000-158555 A JP2004-012542 JP 2004-025846 A

  An object of the present invention is to produce an elastomer molded body that can be easily detached from the mold and removed from the mold without causing tearing, etc., even if it is a thin film molded body after the elastomer raw material is charged and cured The present invention provides a method and a blade member for an electrophotographic apparatus using the method.

  The inventors of the present invention have conducted intensive research on a method for producing an elastomer molded body using a mold. As shown in the partial schematic configuration diagram of FIG. 5, the centrifugal mold 10 has a release layer 11 on the surface 10 a, and a conventional mold that is not subjected to mold release treatment on the surface 10 b (Patent Document 1). 3, 4) was used to form a thin-film elastomer molded body 13 on the release layer 11. Then, when the thin-film elastomer molded body 13 was peeled off from the mold 10 after curing, it was easily peeled between the release layers 11 as shown in FIG. 6, but it adhered to the surface 10b. Occurs. In such a case, in the case of a molded body having a thickness of about 0.5 mm to 2.0 mm, it is difficult to remove the elastomer molded body from the mold 10 although it is not possible to completely peel off the molded body. It becomes a mold defect. Specifically, when the thin film-shaped molded body 13 is forcibly peeled off, the molded body 13 is deformed, and when the elastomer is fully stretched, the molded body is bent and bonded due to the shrinkage of the rubber that occurs at the moment of release. It turns out that tearing occurs in the worst case. However, the present inventors have completed the present invention by obtaining the knowledge that the mold surface 10b is subjected to a release treatment different from that of the surface 10a to suppress the occurrence of these demolding defects.

  The present invention uses a molding die in which a plurality of surfaces are subjected to different mold release treatments in a method for manufacturing an elastomer molded body in which a molded body is manufactured by supplying an elastomer raw material to a molding die having a plurality of surfaces. The present invention relates to a method for producing an elastomer molded article.

  The present invention also relates to a blade member for an electrophotographic apparatus, which is produced using the method for producing an elastomer molded body.

  The method for producing an elastomer molded body of the present invention can be easily detached and removed from the mold without causing tearing even if the elastomer raw material is charged and cured, and even a thin film-shaped molded body is produced. .

  The method for producing an elastomer molded body according to the present invention is a method for producing an elastomer molded body in which an elastomer raw material is produced by supplying an elastomer raw material to a mold having a plurality of faces, and different mold release treatments are performed on each of the plurality of faces. It is characterized by using a formed mold.

  The mold used in the method for producing an elastomer of the present invention has a plurality of surfaces. The plurality of surfaces may be either flat or curved surfaces. The mold having a plurality of surfaces may be any mold having at least two surfaces arranged with an intersection angle. Specific examples of the shape include a cylindrical shape, a rectangular parallelepiped shape, and a cubic shape. The cylindrical shape is preferable when a thin film-like molded body is obtained by centrifugal molding.

  A plurality of different surfaces are subjected to different mold release treatments. An example of using a drum-shaped centrifugal mold as the mold will be described. As shown in the schematic perspective view of FIG. 1 and the configuration diagram of the main part of FIG. 2, the centrifugal mold has a cylindrical inner peripheral surface 1a and a cylindrical inner peripheral surface as a plurality of surfaces subjected to different mold release treatments. And a pair of edge peripheral surfaces 1b provided substantially vertically at both ends. Different mold release treatments are performed on the cylindrical inner peripheral surface 1a and the edge peripheral surface 1b provided substantially perpendicular to both ends of the cylindrical inner peripheral surface. Here, the same mold release treatment may be applied to the pair of edge peripheral surfaces. Moreover, the edge peripheral surface provided substantially perpendicularly at both ends of the inner peripheral surface of the cylinder may be provided on either side, or may be provided over the entire bottom surface of the cylinder instead of the peripheral surface. .

  As the mold release treatment applied to the cylindrical inner peripheral surface, a silicone oil release agent (for example, trade name KS707 manufactured by Shin-Etsu Chemical Co., Ltd.) or a silicone resin baking type release layer (for example, product manufactured by Shin-Etsu Chemical Co., Ltd.) is used. The name SEPA-COAT). An example of the mold release treatment performed on the inner peripheral surface of the cylinder is a process of providing a mold release layer made of silicone rubber or the like. In the case of treatment with a silicone oil-based release agent, the release agent is likely to be transferred to a molded body and to variation in coating operation, and in the case of treatment by baking of a silicone resin, the processing is troublesome. When used as a developer amount regulating blade of an electrophotographic apparatus, it is necessary to further roughen the surface of the molded body after centrifugal molding. In the case of a release treatment that provides a release layer such as silicone rubber, there is no migration of the release agent to the molded body, and there is no need for a release treatment for each molding, and the surface of the release layer is roughened. It is preferable because the surface roughness can be transferred simultaneously with the molding, and the production efficiency can be improved.

  The silicone rubber layer serving as the release layer may be formed by coating such as spraying or brushing, but is preferably one that can be molded with a liquid uncured material that can be centrifuged. When the cylindrical inner peripheral surface is formed by centrifugal molding, the silicone rubber layer is formed to a thickness that absorbs and cancels out the vibration even when the center axis of the molding die is shaken. For this reason, as a molded object centrifugally formed on the silicone rubber layer, a uniform thickness can be obtained. Examples of such liquid uncured silicone rubber include moisture curable liquid silicone rubber and two-component curable liquid silicone. Specifically, for example, KE-1204A / B (manufactured by Shin-Etsu Chemical Co., Ltd.) and the like are preferable as the two-component addition thermosetting liquid silicone from the point that a release layer can be formed in a short time. Another reason why a silicone rubber layer made of a liquid uncured material that can be centrifugally molded, such as a two-component curable liquid silicone, is preferable is that a mold having scratches can be regenerated and used. In the case of the above-mentioned oil-based mold release agent or silicone resin baking mold release layer, for example, a mold with a scratch of 0.1 mm cannot be used. It can be used by laminating a heat-curable liquid silicone rubber layer. The thickness of the silicone rubber layer to be laminated can be set to 0.5 mm, for example.

  Centrifugal molding of the silicone rubber layer can be performed by introducing a liquid silicone rubber raw material into a mold, rotating the mold to form a thin film on the inner peripheral surface of the cylinder, and heating and curing. As for the thickness of a silicone rubber layer, 0.5-10 mm can be mentioned, for example. If the silicone rubber layer is 0.5 mm or more, it is possible to easily correct the deflection of the mold and scratch the mold, and if the silicone rubber layer is 10 mm or less, the thermal conductivity to the molded body is prevented from being lowered. be able to.

  In addition, it is preferable to roughen the surface of the silicone rubber layer when producing a molded body for a developer regulating blade member of an electrophotographic apparatus. Since the surface roughness of the silicone rubber layer is transferred to the surface of the molded body and the surface of the molded body reflects the surface roughness of the silicone rubber layer, it is preferable to set the surface roughness of the developer amount regulating blade. Specific examples of the surface roughness Rzjis of the silicone rubber layer include 2 to 20 μm. If the surface roughness is 2 μm or more, density unevenness can be suppressed, and if the surface roughness is 20 μm or less, the developer can be prevented from slipping through. In order to form a silicone rubber layer having such a surface roughness, it can be adjusted by the type and particle size of the solid lubricant mixed in the liquid silicone rubber.

  Here, as the surface roughness value, a 10-point roughness average (Rz), SE3500 (manufactured by Kosaka Laboratory Co., Ltd.) is used as a measuring instrument, and a value obtained by a measuring method according to JISB0601 can be adopted.

  The mold release treatment applied to the peripheral edge surface or bottom surface provided substantially perpendicular to both ends of the cylindrical inner peripheral surface may be any mold release treatment that is different from the cylindrical inner peripheral surface. The release effect may be lower than that of the peripheral surface release treatment. A wide range of materials can be used as the material used for the mold release treatment applied to the peripheral surface or the bottom surface, compared with the inner peripheral surface of the cylinder. Preferred examples include alkylsiloxane and polyfluorinated ethylene. For mold release treatment on the peripheral surface or bottom surface, silicone oil release agent coating, silicone resin baking release layer, silicone rubber release layer molding, treatment of mold surface with fluorine compound, for release For example, adhesion of a tape can be mentioned. Specifically, for example, SEPA-COAT (manufactured by Shin-Etsu Chemical Co., Ltd.) is applied to the peripheral surface or bottom surface as a silicone resin-based baking type. Next, the release layer can be formed by baking at 150 ° C. for 1 hour. Further, the mold release treatment applied to the peripheral surface or the bottom surface may be a treatment using liquid silicone rubber, and the uncured liquid silicone rubber is separated by coating molding such as spray spraying, brush coating, syringe dropping or the like. The mold layer may be molded. Examples of adhesion of the release tape include a method in which a silicone tape (silicone tape No. 100 manufactured by Nipper Co., Ltd.) or a polyfluorinated ethylene tape (Nittofuron adhesive tape manufactured by Nitto Denko) is attached. . The release tape can easily and sufficiently perform its function, and it is very easy to make.In addition, when dirt occurs or breaks, the reworking work is much easier than metal surface treatment. preferable.

  The mold release treatment applied to the peripheral surface or bottom surface can be applied to the minimum necessary range that does not contact the mold release processing applied to the cylindrical inner peripheral surface, but is performed prior to the mold release processing applied to the cylindrical inner peripheral surface. Further, it can be provided in a range that is a lower layer of a release layer applied to the inner peripheral surface of the cylinder. The release treatment applied to the peripheral surface or bottom surface of the cylinder is because the release agent, release layer, release tape, etc. as the treatment can be fixed to the release layer on the cylindrical inner surface. If the surface release processing is preceded, the release processing for a plurality of surfaces can be easily performed. Specifically, when the mold release treatment applied to the peripheral surface or the bottom surface forms the release layer, as shown in FIG. 2, the release layer 2 is formed on the peripheral surface 1b of the cylindrical inner peripheral surface of the mold. The release layer 1 can be provided on the cylindrical inner peripheral surface 1a. Further, when the mold release treatment applied to the peripheral surface or the bottom surface is a surface treatment of the mold, as shown in FIG. 3, the entire surface treatment 4 of the mold is performed with a fluorine compound, and thereafter, the cylindrical inner peripheral surface 1a is applied. A release layer 1 can be provided. In the case where the release treatment applied to the peripheral surface or the bottom surface is adhesion of a release tape, as shown in FIG. 4, the release tape 5 is provided up to the edges of the peripheral surface 1b and the cylindrical inner peripheral surface 1a. Then, the release layer 1 can be provided on the cylindrical inner peripheral surface 1a including the peripheral edge where the release tape 5 is provided. In this way, by providing the release tape 5 to the edges of the peripheral edge surface 1b and the cylindrical inner peripheral face 1a, when releasing the release layer 1, the release tape 5 is peeled off to facilitate the release layer. Can be peeled off easily, and re-stretching can be easily performed.

  As a molding method applicable to the method for producing an elastomer of the present invention using the above-mentioned molding die, in-mold molding in which a material having fluidity is injected into a molding die having the shape of a molded body and cured, or centrifugal Examples include molding, injection molding, extrusion molding, and the like.

  In the method for producing an elastomer molded article of the present invention, the elastomer raw material to be used is not particularly limited, and any material may be used. As the elastomer raw material, the polyurethane elastomer molded body having high adhesion to the mold when thermally cured is often used as a blade member of an electrophotographic apparatus. Can be mentioned. Specific examples of such a prepolymer include a polyurethane prepolymer obtained by reacting a polyisocyanate and a polyol. Any polyisocyanate may be used as long as it has two or more isocyanate groups. For example, 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2,6- Tolylene diisocyanate (2,6-TDI), xylene diisocyanate (XDI), 1,5-naphthylene diisocyanate (1,5-NDI), p-phenylene diisocyanate (PPDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate ( IPDI), 4,4′-dicyclohexylmethane diisocyanate (hydrogenated MDI), tetramethylxylene diisocyanate (TMXDI), carbodiimide-modified MDI, polymethylenephenyl polyisocyanate (PAPI), etc. It can be. These compounds can be used alone or in combination of two or more.

  The polyol used in the prepolymer is not limited as long as it has two or more OH groups, butylene adipate polyester polyol, hexylene adipate polyester polyol, ethylene glycol (EG), diethylene glycol (DEG), propylene glycol (PG). ), Dipropylene glycol (DPG), 1,4-butanediol (1,4-BD), 1,6-hexanediol (1,6-HD), 1,4-cyclohexanediol, 1,4-cyclohexanedi Examples thereof include divalent alcohols such as methanol, xylylene glycol (terephthalyl alcohol) and triethylene glycol, and trivalent alcohols such as trimethylolpropane, glycerin, pentaerythritol and sorbitol. These can be used alone or in combination of two or more.

  In addition to the prepolymer, a urethanization catalyst may be included as the elastomer raw material. Specific examples of the urethanization catalyst include tertiary alcohols such as amino alcohols such as dimethylethanolamine, trialkylamines such as triethylamine, N, N, N ′, N′-tetramethyl-1,3- Examples thereof include tetraalkyldiamines such as butanediamine, triethylenediamine, piperazine-based, triazine-based, and metal catalysts such as dibutyltin dilaurate.

  The compounding quantity of the said urethanization catalyst can be 10-500 ppm in an elastomer raw material, for example. If the compounding amount of the urethanization catalyst is 10 ppm or more, the reaction can be promoted and the remaining amount of unreacted isocyanate can be reduced. Moreover, if it is 500 ppm or less, the progress of reaction can be suppressed before injection | pouring to a shaping | molding die, it can prevent that it becomes high viscosity, and uniform centrifugal molding can be performed.

  Additives such as pigments, plasticizers, waterproofing agents, antioxidants, UV absorbers, light stabilizers, fillers, vulcanization accelerators, lubricants, conductive agents, etc., as necessary, to the above elastomer materials can do.

  The blade member for an electrophotographic apparatus of the present invention is produced using the method for producing an elastomer molded body of the present invention. For example, a blade member can be cut out from a thin-film cylindrical polyurethane molded body obtained by the method for producing an elastomer molded body, thereby forming a blade member for a cleaning blade or a developer regulating blade. This blade member was joined to a support member such as a steel plate, a stainless steel plate, a galvanized chromate coated steel plate, a chrome-free steel plate, 6-nylon or 6,6-nylon, and applied electrophotographic technology via the support member. It can be installed in an electrophotographic apparatus.

  EXAMPLES Next, although an Example is given and this invention is demonstrated in detail, the technical scope of this invention is not limited to these Examples.

[Preparation of elastomer material]
As an elastomer raw material, MDI-polybutylene adipate prepolymer (Coronate 4387: manufactured by Nippon Polyurethane Industry Co., Ltd., isocyanate value 6.2% by mass) was used. Further, 1,4-butanediol and trimethylolpropane were mixed at 70:30, and 1000 ppm of TEDA (triethylenediamine) was added as a curing agent.

  Until the polyurethane prepolymer is completely dissolved and transparent, it is preheated in an electric furnace at 80 ° C. for about 8 hours, and the curing agent is mixed so that the molar ratio of hydroxyl groups to isocyanate groups is 0.95. The raw material was obtained.

[Molding of molded body]
[Example 1]
A centrifugal mold having a diameter of 400 mm and a width of 250 mm was used. A Teflon tape (Nittofuron adhesive tape manufactured by Nitto Denko Corporation) was applied once to the peripheral surface in the same manner as the release layer 2 shown in FIG. Next, two-component heat addition curing type silicone rubber (KE1204A / B manufactured by Shin-Etsu Chemical Co., Ltd.) is mixed in two components, vacuum defoamed for 3 hours, heated to 130 ° C., and centrifuged at 800 rpm. An amount equivalent to 1 mm in thickness was added. The liquid silicone layer was cured at 130 ° C. and 800 rpm for 2 hours to produce a release layer on the inner circumferential surface of the cylinder.

  The elastomer raw material was added so that the thickness of the molded body was equivalent to 1 mm. After the addition, the centrifugal mold was kept at a rotational speed of 800 rpm and 130 ° C. and cured for 45 minutes.

[Peelability evaluation]
Regarding the obtained thin-film cylindrical polyurene elastomer molded body, the ease of peeling when removing it from a centrifugal mold is as follows. The number of occurrences of defects of ˜4 was evaluated as follows. The evaluation was carried out by repeatedly molding the molded body 50 times, and the number of defects occurring during the 50 times was used as an evaluation standard. The results are shown in Table 1.
1. The molded body is torn off and the end remains in the mold.
2. A force is applied when the molded body is taken out, and the shape of the molded body is deformed.
3. The end of the molded body is fixed and a tear is generated.
4). It cannot be completely demolded.
A: 2 or less B: 5 or less x: 5 or more

[Example 2]
Instead of the Teflon tape attached as shown in the release layer of Example 1 (reference numeral 2 in FIG. 2), it is applied to the cylindrical inner peripheral surface of the centrifugal mold as in the case of the release tape 5 shown in FIG. Affixed once to the peripheral surface. Other than that, the molded body was molded in the same manner as in Example 1, and the peelability when removing from the centrifugal mold was evaluated. The results are shown in Table 1.

[Example 3]
Instead of the Teflon tape attached as shown in the release layer of Example 1 (reference numeral 2 in FIG. 2), a silicone resin baking type release agent (SEPA-COAT manufactured by Shin-Etsu Chemical Co., Ltd.) is sprayed. A release layer was formed on the entire inner peripheral surface of the cylinder and the peripheral surface of the centrifugal mold. Thereafter, in the same manner as in Example 1, a release layer was produced on the cylindrical circumferential surface. In the same manner as in Example 1, the molded body was molded, and the peelability when removing from the centrifugal mold was evaluated. The results are shown in Table 1.

[Example 4]
In the same manner as in Example 2, a release tape was provided on the peripheral surface of the centrifugal mold so as to hang on the cylindrical peripheral surface, and silicone rubber was introduced into the cylindrical peripheral surface. Before the silicone rubber is cured, the same silicone rubber is diluted 5 times with a hydrocarbon solvent (Actrel manufactured by Exxon Chemical Co., Ltd.), and then the solid lubricating fine particles (Torefill R-902A manufactured by Toray Dow Corning) are the same as the silicone. After adding and dispersing in an amount, the silicone surface was sprayed to produce a release layer having a surface roughness Rzjis of 8 μm. In the same manner as in Example 1, the molded body was molded, and the peelability when removing from the centrifugal mold was evaluated. The results are shown in Table 1.

[Comparative Example 1]
A release layer was produced on the cylindrical circumferential surface in the same manner as in Example 1 except that the release tape was not provided on the peripheral surface of the centrifugal mold. In the same manner as in Example 1, the molded body was molded, and the peelability when removing from the centrifugal mold was evaluated. The results are shown in Table 1.

[Comparative Example 2]
A silicone oil release agent (KS707, manufactured by Shin-Etsu Chemical Co., Ltd.) was introduced into a centrifugal mold heated to 130 ° C. and rotated at 100 rpm, and the silicone oil release agent was applied to the inner peripheral surface of the cylinder. In the same manner as in Example 1, the molded body was molded, and the peelability when removing from the centrifugal mold was evaluated. The silicone oil release agent was applied every time the molded body was molded. The results are shown in Table 1.

  From Example 1 and Comparative Example 1, it can be seen that by performing mold release treatment on the peripheral surface of the edge, it is possible to reduce defects during demolding of the molded body and remarkably improve the peelability of the molded body. From Example 3, it can be seen that the release treatment of the peripheral edge surface promotes improvement of peelability by providing a release tape, a release layer onto which a siloxane resin is baked, and the like.

  Further, as a result of applying the silicone-based mold release agent only to the inner peripheral surface of the cylinder from Comparative Example 2, the defect occurrence rate is substantially the same as that of Comparative Example 1, and the mold release treatment on the peripheral surface is made easier to release the molded body. It can be seen that it contributes greatly.

  As described above, each surface of a mold having a plurality of surfaces is subjected to different mold release treatments, thereby facilitating demolding as well as surface roughness molding, regeneration of mold release processing, and molds. It is also preferable in terms of usability and the like, and it can be seen that production efficiency can be improved.

It is a schematic perspective view which shows an example of the centrifugal mold used for the manufacturing method of the elastomer molded object of this invention. It is a schematic block diagram of the principal part of an example of the centrifugal mold used for the manufacturing method of the elastomer molded object of this invention. It is a schematic block diagram of the principal part of an example of the centrifugal mold used for the manufacturing method of the elastomer molded object of this invention. It is a schematic block diagram of the principal part of an example of the centrifugal mold used for the manufacturing method of the elastomer molded object of this invention. It is a schematic block diagram which shows the conventional centrifugal mold. It is a schematic block diagram which shows the conventional centrifugal mold.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 Release layer 1a Cylinder inner peripheral surface 1b Edge peripheral surface 3 Molded body 4 Treatment with a fluorine compound 5 Release tape

Claims (11)

  In a manufacturing method of an elastomer molded body in which a molded body is manufactured by supplying an elastomer raw material to a molding die having a plurality of surfaces, a molding die having a different release treatment applied to each of the plurality of surfaces is used. A method for producing an elastomer molded body.   2. The method for producing an elastomer molded body according to claim 1, wherein the molding die is a centrifugal molding die, and has a cylindrical inner peripheral surface and a bottom surface or an edge peripheral surface provided at an end of the cylindrical inner peripheral surface. .   3. The method for producing an elastomer molded body according to claim 2, wherein a cylindrical inner peripheral surface of the centrifugal mold has a release layer formed of a material containing silicone rubber.   4. The method for producing an elastomer molded body according to claim 3, wherein the release layer is centrifugally molded by supplying liquid silicone rubber.   The method for producing an elastomer molded article according to claim 4, wherein the liquid silicone rubber is a two-component curable silicone rubber.   The method for producing an elastomer molded product according to any one of claims 3 to 5, wherein the release layer has a surface roughness Rzjis in the range of 2 µm to 20 µm.   The elastomer molded body according to any one of claims 2 to 6, wherein the bottom surface or the peripheral edge surface of the centrifugal mold has a release layer formed of a material having alkylsiloxane or polyfluorinated ethylene. Method.   8. The method for producing an elastomer molded article according to claim 7, wherein the release layer contains a silicone tape or a polyfluorinated ethylene tape.   The method for producing an elastomer molded body according to any one of claims 1 to 8, wherein the elastomer raw material contains a prepolymer for a polyurethane elastomer molded body.   The method for producing an elastomer molded body according to any one of claims 1 to 9, wherein the elastomer molded body is a blade member for an electrophotographic apparatus.   A blade member for an electrophotographic apparatus, which is produced using the method for producing an elastomer molded article according to any one of claims 1 to 10.

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