JP4881694B2 - Mold for blade for electrophotographic apparatus and method for manufacturing the same - Google Patents

Description

  The present invention relates to a molding die for a blade such as a cleaning blade and a developing blade mounted on a process cartridge, and a method for manufacturing the blade, and more particularly to a high-precision blade for reducing the influence of warping or bending of a support plate. The present invention relates to a mold and a molding method.

  In recent years, the output image of an electrophotographic apparatus has been developed in color and high definition, and in order to improve the image quality, it is necessary to increase the accuracy of the blade. It is more preferable that the high accuracy of the blade is realized in a state where the blade is mounted on the electrophotographic apparatus, that is, in a state where the blade is used, in addition to the high accuracy of the blade alone.

In conventional blade molds, liquid resin is poured in a state where the part of the support plate where the adhesive is not applied is sandwiched between two mold pieces, and the liquid resin is prevented from leaking from the gap between the mold and the support plate. (For example, refer to Patent Document 1).
Japanese Patent Laid-Open No. Sho 62-30283

  However, in the disclosed technique of the above-mentioned Patent Document 1, the support plate is clamped by the mold over the entire length of the support plate for the purpose of preventing the liquid resin from leaking. Then, the liquid resin is cast in a state in which the warping and bending of the support plate are corrected. After that, when the blade in which the liquid resin is integrally cured with the support plate is removed from the mold, the warp or bending of the support plate corrected by the mold is caused by the springback action within the elastic deformation region of the support plate. Restore to warping and bending. As a result, the rubber-like elastic body formed integrally with the support plate is subject to deformation such as warping and bending as the support plate is spring-backed.

  In addition, when the conventional blade is mounted on the electrophotographic apparatus, the correlation between the blade mounting seat surface of the electrophotographic apparatus and the fixed seat surface of the mold is not considered, and the support plate is also warped or bent as described above. There are not a few. For this reason, if there is a difference in the size of the seat surface, the positional relationship of the seat surface, etc., between the blade mounting seat surface of the electrophotographic apparatus and the fixed seat surface of the mold, the flatness accuracy of the support plate in the mold is improved. It is not reproduced when the blade is mounted on an electrophotographic apparatus. As a result, neither the deformation of the rubber-like elastic body formed integrally with the support plate nor the accuracy in the mold can be maintained.

  In the case of a cleaning blade of an electrophotographic apparatus, if the rubber-like elastic body of the blade is warped or bent, the contact pressure with the photosensitive drum will be uneven, and the residual toner on the photosensitive drum will be unevenly cleaned. It causes a defect.

  Also, in the case of the developing blade, if the rubber-like elastic body is warped or bent, when the toner passes between the developing blade and the current developing roller, unevenness occurs in the tribo generated in the toner due to frictional charging, resulting in density unevenness during printing, etc. An image defect occurs.

  In order to solve the above problems, the present invention provides a molding die and a manufacturing method capable of reducing the influence of warping and bending of a support plate and reproducing the blade accuracy during molding when the blade is mounted on an electrophotographic apparatus. For the purpose.

  In order to achieve the above object, a molding die for an electrophotographic apparatus blade of the present invention is an electrophotographic apparatus blade molding mold in which a rubber-like elastic body is integrally formed at one end in the width direction of a support plate. A relief surface formed by providing a step with respect to the fixed seat surface so that a gap is formed between the fixed seat surface that supports both ends of the support plate in the longitudinal direction and the support plate supported by the fixed seat surface; It is characterized by having.

  As described above, when the support plate is set in the mold, the support plate abuts on the fixed seat surface of the mold, and a portion other than the fixed seat surface is provided with a clearance surface that forms a gap with the support plate. For this reason, even if the support plate is warped or bent, even if it does not contact or does not contact the flank, the deformation of the support plate due to contact is reduced, and the spring back amount of the support plate after demolding also decreases. To do.

  The molding die of the present invention is arranged so as to face the reference mold having the fixed seat surface and the reference mold, and presses the support plate supported by the fixed seat surface of the reference mold against the fixed seat surface. You may have a press type | mold provided with the press means. The pressing means may include a pressing portion and a biasing unit that biases the pressing portion in the fixed seat surface direction. In this case, since the support plate is pressed against the fixed seat surface during molding, the rubber-like elastic body of the blade can be molded based on the fixed seat surface side of the support plate.

  Further, the pressing portion may be a member that presses a peripheral portion of a screw hole for mounting a blade on the blade mounting seat surface of the electrophotographic apparatus formed on the support plate. In this case, since the support plate is fixed to the fixing seat surface of the mold with a predetermined pressing force at the position where the blade is screwed to the electrophotographic apparatus or in the vicinity of the screwing position, when the blade is molded and mounted on the electrophotographic apparatus The same position of the blade support plate can be fixed with a predetermined pressing force.

  In the molding die of the present invention, a cavity for curing a liquid resin to mold a rubber-like elastic body is continuously formed with respect to the flank, and a liquid reservoir groove is formed along the cavity on the flank. It may be formed. By providing the liquid storage groove, the liquid resin starts to be cured while the liquid resin is filled in the liquid storage groove, and the viscosity of the liquid resin is increased, so that the liquid resin is prevented from flowing out of the liquid storage groove. Further, depending on the type of the liquid resin, the gap through which the liquid resin passes is enlarged at the liquid reservoir groove portion, so that the action of capillary action is reduced and the flow of the liquid resin can be suppressed.

  Further, the step between the fixed seat surface and the flank may be in the range of 5 μm to 60 μm, or more preferably in the range of 20 μm to 50 μm. The level of the step can be selected as appropriate based on the processing accuracy of the flatness of the fixed seat surface and the viscosity of the liquid resin, taking into account the effect of reducing the spring back of the support plate due to the step and the leakage of the liquid resin from the mold from the step. is there.

  The shape of the fixed seat surface is the same as the blade mounting seat surface of the electrophotographic apparatus on which the blade is mounted, and the positional relationship of the fixed seat surface with respect to the blade is the same as the positional relationship of the blade mounting seat surface with respect to the blade. There may be. The shape of the first positioning member formed on the fixed seat surface for positioning the support plate with respect to the fixed seat surface is the same as that of the blade support plate formed on the blade mounting seat surface. And the positional relationship of the first determining member on the fixed seat surface and the positional relationship of the second determining member on the blade mounting seat surface are the same. Also good. In this case, the same surface and the same position of the support plate of the blade can be shared by the fixed seat surface in the mold and the mounting seat surface in the electrophotographic apparatus.

  The method for manufacturing a blade for an electrophotographic apparatus according to the present invention is the method for manufacturing a blade for an electrophotographic apparatus in which a rubber-like elastic body is integrally formed at one end in the width direction of a support plate. The support plate is fixed to the fixed seating surface of the molding die of the blade, the liquid resin is cast, the liquid resin is heated and cured, and a rubber-like elastic body is integrally formed at one end in the width direction of the support plate. Thereafter, the rubber-like elastic body is cut into a predetermined shape.

  According to the above-described manufacturing method of the present invention, it is possible to manufacture a blade with substantially the same conditions for mounting the blade of the electrophotographic apparatus and fixing the support plate at the time of forming the blade, and reducing the deformation of the support plate at the time of forming The liquid resin can be cast and heat-cured.

  ADVANTAGE OF THE INVENTION According to this invention, the shaping | molding die which can reduce the bad influence of the springback phenomenon resulting from the curvature and curvature of a support plate can be comprised, and the manufacture of the braid | blade which improves the flatness of a blade using a shaping | molding die can be performed.

  Further, according to the present invention, it is possible to configure a blade mold that shares the pressing force and the shape and position of the seating surface on which the blade is mounted on the electrophotographic apparatus, and the pressing position for pressing and fastening the blade to the seating surface. Furthermore, according to the present invention, it is possible to produce a blade that can reproduce the plane accuracy when the blade is molded, when it is mounted on the electrophotographic apparatus, regardless of the warp or the bending of the support plate, using the mold.

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

  FIG. 1 is a perspective view showing a state in which the blade mold of this embodiment is opened. FIG. 2 is a perspective view of the pressing mold according to the present embodiment as viewed from the pressing surface side. FIG. 3 is a longitudinal cross-sectional view seen in the AA direction shown in FIG. 1 for showing a step which is a gap between the support and the mold when the mold is closed. 4 is a cross-sectional view in the short-side direction as seen in the BB direction shown in FIG.

  The reference mold 1 and the pressing mold 2 of the mold of this embodiment are matched by fitting the mold matching holes 11 formed on the parting surfaces at both ends of the molds 1 and 2 with the mold matching shaft 21. The The parting surfaces 12 and 22 of the reference mold 1 and the pressing mold 2 come into contact with each other, and the reference mold 1 and the pressing mold are clamped by fastening means (not shown). The reference mold 1 and the pressing mold 2 are provided with a cavity 1f and a cavity 2f, and a cavity corresponding to the rubber-like elastic body 32 before cutting is formed.

  Further, the reference mold 1 is provided with a fixed seat surface 1b for fixing both longitudinal ends of the support plate 31 on the same surface, and receives one surface of the support plate 31. The fixed seat surface 1b is provided so as to have the same shape and the same position as the blade mounting seat surface of the electrophotographic apparatus to which the blade formed by the molding die of the present embodiment is mounted. Also, the shape and position of the positioning portion 1a provided on the fixed seat surface 1b for positioning the support plate 31 is the same as the positioning portion formed on the blade mounting seat surface of the electrophotographic apparatus. Yes. Thereby, the same surface and the same position of the support plate 31 can be shared by the fixed seat surface in the mold and the mounting seat surface in the electrophotographic apparatus.

  The clearance surface 1c, which is a portion other than the fixed seat surface 1b in the thickness direction of the support plate 31, is provided with a step G1 in a direction in which a gap is formed between the fixed seat surface 1b and the support plate 31 (FIGS. 3 and 4). reference). Further, a step G2 (see FIGS. 3 and 4) is provided in a direction in which a gap is formed between the other surface of the support plate 31 and the flank 2c of the pressing die 2. These flank surfaces 1c and 2c are formed continuously with respect to the cavities 1f and 2f.

  The flank 1c of the reference mold 1 and the flank 2c of the pressing mold 2 are provided with reservoirs 1g and 2g, respectively, along the width direction end surfaces of the cavities 1f and 2f for molding the rubber-like elastic body 32, respectively.

  Further, the pressing die 2 is provided with a pressing member 2e that is positioned by pressing the support plate 31 against the fixed seat surface 1b. The pressing member 2e is configured to be biased toward the fixed seat surface 1b by a spring 2e '. In the present embodiment, the pressing member 2e is a spherical member. A part of the spherical pressing member 2e is fitted into a screw hole 31e formed in the support plate 31, and is biased by a spring 2e 'to press the circumferential portion of the screw hole 31e in the direction of the fixed seat surface 1b. Thus, the support plate 31 is pressed and positioned with respect to the fixed seat surface 1b. Moreover, the pressing position may never be a pressing member having the same shape plane as the seating surface of the screw 7 used when the blade is fixed to the mounting seating surface instead of the spherical pressing member.

  The inlets 1d and 2d constitute a liquid resin inlet by clamping the reference mold 1 and the pressing mold 2 together. The liquid resin becomes the rubber-like elastic body 32 by being cured.

The support plate 31 is positioned in the width direction of the support plate 31 by a notch 31a that engages the positioning portion 1a of the reference mold 1 in the mold. Positioning of the support plate 31 in the thickness direction is determined by pressing the support plate 31 against the fixed seat surface 1b by a pressing member 2e provided on the pressing die 2. The positioning of the support plate 31 in the longitudinal direction is determined by guiding the inner pitch of the notches 31a of the support plate 31 with the inner pitch of the pair of positioning portions 1a. In addition, a screw hole portion 31e is formed in the vicinity of the notch 31a. As described above, the screw hole 31e is also used for positioning the support plate 31.
(Blade manufacturing process)
Next, the manufacturing process of the blade using the mold of the present embodiment having the above-described structure will be described.

  The support plate 31 is set on a molding die having the above-described configuration after a primer is applied and dried at a joint portion with the rubber-like elastic body 32.

  Here, the support plate 31 is usually a galvanized steel plate in which a cold-rolled steel plate is electrogalvanized and a rust-proof coating is further formed. Then, while feeding out the galvanized steel sheet wound around the drum, it is wound by a flatness straightening machine such as a roll leveler to correct warping and bending of the steel sheet, and then punched by a press machine. However, even if it corrects with a roll leveler, it cannot correct by the unevenness of correction resulting from a slight difference in the thickness of the steel sheet, unevenness of stress remaining on the steel sheet, and the like. In addition, the support plate is warped and bent during the punching process into the support plate shape and the L-shaped bending process for enhancing the bending rigidity of the support plate. Further, as a method for removing the warp or bend of the support plate caused by the press work, a process such as grinding may be considered, but it is not a suitable method because the rust preventive film of the steel sheet is peeled off.

  When the support plate 31 in which warpage or bending remains is pressed and positioned so as to come into contact with the fixed seat surface 1b by the pressing member 2e, for example, a bend W occurs in the thickness direction of the support plate 31 as shown in FIG. In the case of a molding die in which no step is formed, when the die is clamped in this state, a correction force is applied to the bending W. Then, a springback occurs in the support plate 31 after demolding, which causes distortion in the rubber-like elastic body 32.

  On the other hand, in the molding die of the present embodiment, the step G1 is provided between the fixed seat surface 1b and the flank 1c of the reference die 1, and therefore the support plate 31 is flank under the condition of step G1 ≧ bend W. Even if it does not contact 1c, or even if it contacts, it does not cause correction in the thickness direction. Further, when the condition of step G1 <bend W, correction occurs in the thickness direction of the support plate 31, but “correction amount = bend W−step G1”, and the correction amount of the support plate 31 is reduced by an amount corresponding to the step G1. This can reduce the amount of springback.

  Further, consider a case where the support plate 31 is bent in the direction opposite to the bend W in FIG. Even in this case, the distance between the fixed seating surface 1b of the reference mold 1 and the flank 2c of the pressing mold 2 is a value obtained by adding a step G2 to the maximum thickness of the support plate 31 (G2> 0). Set to For this reason, the correction amount of the support plate 31 can be reduced by an amount corresponding to the step G2, similarly to the step G1 described above.

  For the deformation, the steps G1 and G2 are preferably set so that the support plate 31 does not contact the flank surfaces 1c and 2c. However, it is necessary to consider liquid leakage from the gap between the flank surfaces 1c and 2c and the support plate 31. For this reason, the steps G1 and G2 indicate the viscosity of the liquid resin, the curing time, the surface tension, the wettability with the surface of the mold, and the thickness of the support plate 31 so that the liquid resin stays within the range of the flank surfaces 1c and 2c. Determined by correlation with tolerance. Note that the actual processing accuracy of the support plate 31 can be easily suppressed to about 60 μm for warping and bending, and therefore the range of the step G1 may be 5 μm ≦ G1 ≦ 60 μm. Further, when the slight back-up of the support plate is allowed in consideration of the viscosity of the liquid resin, the step G1 is preferably 20 μm ≦ G1 ≦ 50 μm.

  Further, the support plate 31 is pressed against each fixed seat surface 1b of the reference mold 1 near the center of the fixed seat surface 1b by a pressing member 2e of the pressing mold 2 with a predetermined pressing force. For this reason, the warp in the width direction and the twist in the diagonal direction of the support plate 31 are corrected and fixed in a fixed shape in the mold.

  In the present embodiment, the support plate 31 is exemplified by a galvanized steel plate, but the surface of a metal plate such as an iron type such as a stainless steel plate, a copper type such as a phosphor bronze plate or a brass plate, or an aluminum type such as an aluminum alloy plate. Further, it is possible to use a material that has been appropriately subjected to surface treatment such as plating, painting, or chemical conversion treatment.

  As described above, after the support plate 31 is positioned in the mold without undergoing correction force or slightly corrected, the liquid resin is injected from the injection port constituted by the injection ports 1d and 2d. inject. The liquid resin flows in the cavities 1f and 2f, reaches the support plate 31, and stops due to flow resistance at a position where the liquid resin slightly enters the flank surfaces 1c and 2c from the lower ends of the cavities 1f and 2f. Liquid reservoir grooves 1g and 2g are formed on the flank surfaces 1c and 2c, but the liquid resin starts to harden and the viscosity of the liquid resin increases while the liquid resin fills the liquid reservoir grooves 1g and 2g. Thus, the outflow of the liquid resin from the liquid storage grooves 1g and 2g is suppressed. In addition, depending on the type of the liquid resin, the gap through which the liquid resin passes is enlarged by the liquid storage grooves 1g and 2g, and the action of the capillary phenomenon is reduced to suppress the flow of the liquid resin. The injection ports 1d and 2d are fixed in the direction of gravity upward from the injection of the liquid resin until the liquid resin is cured.

  In this state, when the liquid resin is heated and cured, the rubber-like elastic body 32 is integrally formed on the primer application portion of the support plate 31, and the rubber-like elastic body 32 is not warped or bent in the mold. It is maintained in a substantially flat surface.

  Here, the rubber-like elastic body 32 of the blade is made of polyurethane elastomer, silicon elastomer or the like. In the case of a polyurethane elastomer, a composition comprising a polymer polyol, a polyisocyanate, a chain extender, a crosslinking agent, a catalyst, and the like is reaction-cured. Usually, a prepolymer method, a semi-one-shot method or a one-shot method is used. Manufactured. In the prepolymer method, an isocyanate group-terminated prepolymer obtained by reacting a polymer polyol and polyisocyanate in advance is used as a main agent, and a chain extender, a crosslinking agent, a catalyst, and the like are mixed as a curing agent. And a curing agent are mixed into a liquid resin. In addition, the semi-prepolymer method is based on an isocyanate group-terminated prepolymer prepared by the same method as the prepolymer method described above, and a polymer polyol is further added to and mixed with a chain extender, a crosslinking agent, a catalyst, etc., and a curing agent is obtained. This is a method in which a main resin and a curing agent are mixed with a casting machine to form a liquid resin. Further, the one-shot method is a method in which a polymer polyol, polyisocyanate, chain extender, cross-linking agent, etc. are simultaneously mixed with a casting machine to form a liquid resin. Usually, the prepolymer method and the semi-one shot method are preferably used because of easy control of the reaction.

  As the polymer polyol, polyester diol, polyether diol, polycarbonate diol and the like are used, but not only the polymer diol but also a polymer triol can be used alone or in combination of two or more. Usually, the number average molecular weight of the polymer polyol used in the prepolymer method or the semi-one shot method is 500 to 5000, and a number average molecular weight of 1000 to 2500 is preferably used.

  The polyester diol includes at least one carboxylic acid such as adipic acid, succinic acid, pimelic acid, sebacic acid, azelaic acid and suberic acid, ethylene glycol (hereinafter referred to as “EG”), propylene glycol (hereinafter referred to as “PG”). 1,4-butanediol (hereinafter referred to as “1,4-BD”), 1,6-hexanediol (hereinafter referred to as “1,6-HD”), neopentyl glycol (hereinafter referred to as “NPG”). Short chain diols such as glycerin, trimethylolpropane (hereinafter referred to as “TMP”), short chain triols such as hexanetriol, or polyester diols and lactone compounds obtained by condensation polymerization with two or more. And polycaprolactone diol obtained by the ring-opening polymerization.

  Polyether diols include those obtained by ring-opening polymerization of cyclic ethers such as polyethylene oxide, polypropylene oxide, trimethylene oxide, and tetrahydrofuran, EG, PG, 1,4-BD, 1,6-HD, NPG. And polyether diols obtained by condensation polymerization.

  Furthermore, examples of the polycarbonate diol include those obtained by condensation polymerization from dialkyl carbonates such as dimethyl carbonate and ethylene carbonate and the short-chain diol.

  Polyisocyanates used with the above polyols include diphnylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), naphthalene diisocyanate (NDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), xylylene diisocyanate (XDI). Can be used alone or in combination of two or more.

Examples of the chain extender include diols such as EG, PG, 1,4-BD, and 1,6-HD.
Examples of the crosslinking agent include trifunctional or more functional crosslinking agents such as glycerin, trimethylolpropane (TMP), hexanetriol, pentaerythritol, and triethanolamine (TEA).

  Polyurethane polymerization catalysts may also be used, tertiary amine catalysts such as triethylenediamine (TEDA) and N-methylmorpholine (NMM), carboxylic acid metal salt catalysts such as potassium acetate and potassium octylate, dibutyltin dilaurate, An organic tin catalyst such as tin octylate or an imidazole catalyst can be used.

  In the case of a silicone elastomer, an addition reaction type liquid silicone elastomer which is excellent in productivity because the by-product is not generated and the curing time can be shortened by heating and is excellent is preferable to the condensation type which generates a by-product upon curing. As a vinyl group-containing organopolysiloxane, a crosslinking agent as an active hydrogen group-containing organopolysiloxane, a catalyst as a platinum compound and other additives as a reaction inhibitor, reinforcing agent, pigment, anti-settling agent, conductive agent, etc. Examples thereof include mixing and stirring, heating and reaction curing.

  In addition, although the mold has shown an example in which the injection port is greatly opened, the parting surfaces 12 and 22 of the reference mold and the pressing mold are expanded to close the injection ports 1d and 2d at the parting surface. An elastomer may be injected from a pin gate that has a structure and is connected to the cavity from the outer peripheral surface of the mold, and in this case, the elastomer type is not limited to liquid but may be a millable type elastomer such as urethane elastomer or silicon elastomer.

  Next, when the blade in which the rubber-like elastic body 32 is formed at one end of the support plate 31 is removed from the mold, the external force is removed from the support plate. As a result, the support plate is moved in the mold by the springback action of the support plate. Return to the shape before correction. However, compared to a conventional case where a fixed seat for receiving a support plate is not provided and a cut-off is provided over the entire length, the deformation reduction effect of the steps G1 and G2 is exhibited, and the springback amount of the support plate can be reduced. . As a result, the deformation of the contact surface 32a of the rubber-like elastic body formed integrally with the support plate can be reduced even in the state of the blade alone.

  Next, in the molded blade, in the state where the support plate 31 is pressed at the same position on the same seating surface as the fixed seating surface 1b of the molding die, the front end portion in the width direction of the rubber-like elastic body 32 is in the longitudinal direction. Cut with a razor blade or the like. At this time, the support plate 31 is reproduced in a corrective posture in the mold, and is cut without distortion of the rubber-like elastic body 32. Therefore, the flatness of the cut surface 32b of the rubber-like elastic body 32 is also high without deformation. Flatness is maintained.

6 and FIG. 7, the support plate 31 of the completed blade 3 is substantially the same as the fixed seating surface 1b and the pressing position of the support plate 31 in the mold. The mounting seat surface 5b is fastened with screws 7 using the pressing position of the mold as a screw hole. For this reason, the correction posture of the support plate 31 in the mold is reproduced in the electrophotographic apparatus. Therefore, the contact surface 32a and the cut surface 32b of the rubber-like elastic body 32 can be slightly deformed, and the contact surface 32a is pressed against the photosensitive drum 6 by an equal amount, so that the contact pressure is uniform over the entire length of the blade. As a result, the toner is normally cleaned from the drum surface. In addition, the escape groove 5g of the electrophotographic apparatus corresponding to the position of the mounting seat surface 5b of the electrophotographic apparatus and the escape portion 5c other than the mounting seat surface 5b and the liquid reservoir groove 1g of the reference mold 1 is a rubber-like elastic body of the blade 3. It sets suitably so that it may not touch 32. Further, the gap between the support plate 31 and the electrophotographic apparatus 5 is softly formed with a malt plane or the like that does not deform the support plate 31 to prevent the toner from leaking to the outside.
Example 1
Examples of the present invention will be described below, but the present invention is not limited to these examples.

  A galvanized steel sheet (trade name: JINCOAT 21; manufactured by Nippon Steel Co., Ltd.) was flattened with a roll leveler and then pressed into a predetermined shape to form a support plate 31. As shown in FIG. 8, both ends in the longitudinal direction of the support plate mounting surface 31b are fixed to the fixed seat surface of the measuring jig 9 having a fixed seat surface having the same shape as the mold with screws 7, and the support plate mounting surface 31b is It was set as the structure which does not contact | abut a jig | tool in parts other than the fixed seat surface 1b. In this state, the contact type low measurement pressure type linear gauge (trade name “LGH-1010c”: manufactured by Mitutoyo Corporation) as a measuring instrument 8 was used to measure warpage and bending other than the primer application part. As a result, the maximum value of the warpage of the support plate mounting surface 31a was 55 μm at the center in the longitudinal direction of the support plate 31 and inside the width direction primer application portion of the support plate 31.

  After the support plate 31 was washed, a primer was applied and dried on the joint portion with the rubber-like elastic body, and set in a mold preheated to 120 ° C.

  Further, a polyurethane elastomer is used as the rubber-like elastic body 32, and 0.097 mol part of polyethylene adipate-based polyester polyol: PAE (trade name “Nipporan 4040” manufactured by Nippon Polyurethane Industry Co., Ltd.) and 1.0 mol part of 4,4'-Diphnylmethane diisocyanate: Mainly based on an isocyanate group-terminated prepolymer obtained by reacting with MDI, and 1.0 mol part of PAE (trade name “Nipporan 4040” manufactured by Nippon Polyurethane Industry Co., Ltd.) And a catalyst of triethylenediamine (TEDA) to 0.025% by mass in a mixture of 2.0 mol parts of 1,4-BD as a chain extender and 1.1 mol parts of trimethylolpropane (TMP) as a crosslinking agent. ) Was added to prepare a curing agent. Next, the main agent and the curing agent are put into each tank of the casting machine, and are supplied to the mixing chamber by each pump so that the ratio of the main agent: the curing agent is 1: 1 by mass ratio. Were mixed uniformly, liquid resin was discharged from the discharge port of the mixing chamber, and injected into the injection port of the mold. The liquid resin was demolded after curing, and the rubber-like elastic body was cut at a predetermined position to obtain a blade. Incidentally, the step G1 between the fixed seat surface 1b and the flank 1c of the reference die 1 of the molding die was 50 μm, the thickness of the support plate 31 and the step G2 of the pressing die was 20 μm (on the fixed seat surface).

The blade is fixed to the measuring jig 9 shown in FIG. 8, and the linear gauge is replaced with a non-contact laser displacement meter (trade name “LK-G30”, manufactured by Keyence Corporation). The vicinity of the ridge line 32c of the contact surface 32a of the rubber-like elastic body is As a result of measurement in the longitudinal direction along the ridgeline, the maximum difference in warpage and bending of the contact surface 32a is 21 μm, which is greatly improved compared to the warpage of the support plate mounting surface 31b before molding, and the process of the electrophotographic apparatus As a result, the accuracy of the cartridge as a cleaning blade was sufficiently satisfied.
(Example 2)
In this example, a molding die in which the parting surface of the molding die is closed and liquid resin is injected from a pin gate connected to the cavity from the outer peripheral surface of the pressing die is used. In addition, an A agent composed of vinyl group-containing organopolysiloxane of addition reaction type liquid silicone rubber (trade name “DY-35” manufactured by Toray Dow Corning Co., Ltd.), and an active hydrogen group-containing organopolysiloxane as a crosslinking agent, The B agent composed of a platinum catalyst or the like was supplied to a static mixer with each pump so that the mass ratio was 1: 1, and the mixture was uniformly stirred and mixed, discharged and filled from the pin gate of the mold to the cavity, and cured by heating. Other than this, a blade was obtained by molding in the same manner as in Example 1.

Using the support plate 31 having a maximum warpage of the fixed mounting surface 31b of 52 μm, the maximum difference in warpage or bending of the contact surface 32a of the completed blade was 18 μm. Also in this embodiment, the same result as in Embodiment 1 can be obtained, which is greatly improved as compared with the warp of the fixed mounting surface 31b before molding, and sufficiently satisfies the accuracy as the developing blade of the process cartridge of the electrophotographic apparatus. As a result.
(Comparative example)
In Example 1, the blade was molded using a molding die in which both the step G1 of the reference die 1 and the step G2 between the support plate 31 and the pressing die 2 were eliminated. In other words, the blade has the same contents as in Example 1 except that there is no fixed seating surface and a molding die that presses in the thickness direction of the support plate 31 over the entire length of the support plate 31 with the reference die 1 and the pressing die 2 is used. Was processed. As a result, the maximum difference in warpage and bending of the contact surface 32a of the blade completed using the support plate having a maximum warp of 55 μm was 87 μm, which was significantly worse than the warp of the support plate before molding. . As a result of evaluating the incorporation into the process cartridge of the electrophotographic apparatus, a cleaning failure occurred and the accuracy as a cleaning blade could not be sufficiently satisfied.

It is a perspective view which shows the open state of the shaping | molding die of an example of this invention. It is the perspective view which looked at the press type | mold of this invention from the press surface side. It is the longitudinal direction sectional view seen in the AA direction shown in FIG. 1 which shows the correlation of the shaping | molding die of this invention and a support plate. It is the transversal direction sectional drawing seen in the BB direction shown in FIG. 1 which shows the press position determination state of the support plate in the shaping | molding die of this invention. It is a figure which shows an example of the curvature and bending of a support plate. 1 is a perspective view showing a state in which a blade of the present invention is mounted on an electrophotographic apparatus. It is a disassembled perspective view of the blade part of an electrophotographic apparatus. It is a figure explaining the method to measure the curvature of a blade, and a curvature.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reference | standard type | mold 1b Fixed seating surface 1c Flank 2 Pressing die 2e Pressing member 32 Rubber-like elastic body

Claims (10)

In a molding die for an electrophotographic blade formed by integrally forming a rubber-like elastic body at one end in the width direction of a support plate,
A fixed seating surface that supports both longitudinal ends of the support plate;
A blade for an electrophotographic apparatus, comprising: a flank formed with a step with respect to the fixed seat surface so that a gap is formed between the support plate and the support plate. Mold. A reference mold having the fixed seat surface, and a pressing means that is disposed to face the reference mold and presses the support plate supported by the fixed seat surface of the reference mold against the fixed seat surface. The molding die for a blade for an electrophotographic apparatus according to claim 1, comprising a pressing die provided. The molding die for a blade for an electrophotographic apparatus according to claim 2, wherein the pressing unit includes a pressing unit and a biasing unit that biases the pressing unit toward the fixed seat surface. The electrophotographic apparatus according to claim 3, wherein the pressing portion presses a peripheral portion of a screw hole for mounting the blade on a blade mounting seat surface of the electrophotographic apparatus formed on the support plate. Blade mold. The shape of the fixed seat surface is the same as the blade mounting seat surface of the electrophotographic apparatus on which the blade is mounted, and the positional relationship of the fixed seat surface with respect to the blade is that of the blade mounting seat surface with respect to the blade. The molding die for an electrophotographic blade according to any one of claims 1 to 4, which has the same positional relationship. The shape of the first positioning member formed on the fixed seat surface for positioning the support plate with respect to the fixed seat surface is the same as that of the blade mounting seat surface. The shape of the second positioning member positioned with respect to the mounting seat surface is the same, and the positional relationship of the first determining member on the fixed seat surface and the second determining member on the blade mounting seat surface The molding die for a blade for an electrophotographic apparatus according to claim 5, wherein the positional relationship is the same. A cavity for curing the liquid resin to mold the rubber-like elastic body is continuously formed with respect to the flank, and a liquid reservoir groove is formed on the flank along the cavity. A molding die for a blade for an electrophotographic apparatus according to any one of claims 1 to 6. The molding die for a blade for an electrophotographic apparatus according to any one of claims 1 to 7, wherein a step between the fixed seat surface and the flank surface is in a range of 5 µm to 60 µm. 8. The molding die for a blade for an electrophotographic apparatus according to claim 1, wherein a step between the fixed seat surface and the flank surface is in a range of 20 μm or more and 50 μm or less. In the method of manufacturing a blade for an electrophotographic apparatus in which a rubber-like elastic body is integrally formed at one end in the width direction of the support plate,
The support plate is fixed to the fixed seat surface of the molding die according to any one of claims 1 to 9, a liquid resin is cast, the liquid resin is heat-cured, and one end of the support plate in the width direction is provided. A method for manufacturing a blade for an electrophotographic apparatus, wherein the rubber-like elastic body is integrally formed, and the rubber-like elastic body is cut into a predetermined shape after demolding.

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