JP2002046135A - Method for manufacturing resin roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a molded roller or particularly a method for releasing a resin roller for preventing a scuff mark generated when a molding is released from a cylindrical mold. SOLUTION: The method for manufacturing the resin roller comprises the steps of disposing a core in the mold for molding having the cylindrical mold and core holding members mounted at both ends of the mold, holding both the ends of the core at the members, injecting a resin in the mold, curing the resin, and releasing the molding from the mold. The method also comprises the step of releasing the roller from the mold in liquid in the case of releasing the roller from the mold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing roller, a charging roller, and the like incorporated in various apparatuses employing an electrophotographic system such as a laser printer, a copying machine, and a facsimile machine.
The present invention relates to a core of a roller such as a transfer roller and a configuration around the core.

[0002]

2. Description of the Related Art Rollers such as a developing roller, a charging roller, and a transfer roller are incorporated in various apparatuses employing an electrophotographic method, such as a laser printer, a copying machine, and a facsimile machine. One example of such a roller is shown in FIG. The roller 10 has a core 21 and a cylindrical molded body 12 formed of resin. A mold for molding such a roller 10 is, for example, as shown in FIG.
3 and a core holding member 14 located at the upper and lower ends of the cylindrical mold 13 for holding the core 21 inserted in the cylindrical mold 13 and sealing both ends of the cylindrical mold 13. And The lower core support member 14 has a cylindrical mold 13.
A resin injection port 16 for injecting a resin material into a roller molding space 15 in the inside is formed, and a resin injection nozzle 18 of a molding machine is pressed from a semicircular nozzle touch portion 19 to the outside of the mold of the resin injection port 16. By doing so, the roller forming space 15
Is led to the resin material.

After the filling of the resin into the mold is completed, the resin in the roller molding space 15 is cured by heating. After the curing of the resin is completed, the core holding member 14 is removed from the cylindrical mold 1.
3 is removed along the axial direction. Next, the core body 21 is extruded with respect to the cylindrical mold 13 or the like,
The molded product held in the cylindrical mold 13 is taken out.

However, when the molded product is pulled out of the cylindrical mold 13 along the axial direction thereof, friction between the outer peripheral surface of the molded product and the inner surface of the cylindrical mold causes the outer peripheral surface of the molded product to have a shark skin. Scratches and cracks may occur.

[0005] In particular, when the resin material is an adhesive resin such as silicon, friction between the outer peripheral surface of the molded product and the inner surface of the cylindrical mold increases, and the release load at the time of releasing the molded product also increases. As a result, the outer peripheral surface of the molded article was rubbed and the scratches increased.

Accordingly, a release agent is applied to the inner surface of the cylindrical mold,
There is a method of reducing friction between the outer peripheral surface of the molded product and the inner surface of the cylindrical mold when removing the molded product, reducing the release load when releasing the molded product, and reducing rubbing scratches. The number of steps for applying the mold agent increases, resulting in an increase in cost.

In addition, the mold and the molded product are sufficiently cooled at the time of release from the mold, the dimension of the outer diameter method of the molded product is reduced, and the gap between the inner diameter of the cylindrical mold and the outer diameter of the molded product is increased. There is a method to reduce the release load when releasing the molded product and reduce the scratches.However, a process and time for sufficiently cooling the cylindrical mold and the molded product are required, resulting in an increase in cost. Become.

In addition, the outer peripheral surface of the molded product may be rubbed and scratched, and the inner surface of the cylindrical mold may be worn, which may deteriorate the durability of the cylindrical mold.

[0009]

As described above, when the molded product is removed from the cylindrical mold 13 along the axial direction thereof, the friction between the outer peripheral surface of the molded product and the inner surface of the cylindrical mold is caused by friction.
In some cases, scratches occurred on the outer peripheral surface of the molded product.

In addition, a mold release agent is applied to the inner surface of the cylindrical mold in advance to reduce friction between the outer peripheral surface of the molded product and the inner surface of the cylindrical mold, and to reduce the release load when the molded product is released. Although there is a method of reducing rubbing scratches, the number of steps of applying a release agent increases.

Therefore, the cost is increased due to a decrease in the rate of non-defective products due to defective scratches on the outer peripheral surface of the molded product and an additional step of applying a release agent.

The present invention has been made in view of such a situation, and an object of the present invention is to provide a method for manufacturing a molded roller, and particularly to prevent a rubbing scratch generated when a molded article is released from a cylindrical mold. An object of the present invention is to provide a method for releasing a resin roller.

[0013]

SUMMARY OF THE INVENTION The present invention provides a cylindrical mold,
A core is disposed in a molding die having a core holding member attached to both ends of the cylindrical mold, and both ends of the core are held by the core holding member. A method of manufacturing a resin roller by injecting and curing a resin and releasing a molded product from inside a cylindrical mold, wherein the resin roller is separated from the inside of a liquid when the resin roller is released from the cylindrical mold. An object of the present invention is to provide a method of manufacturing a resin roller, in which start and end of a mold are performed.

In order to release the resin roller from the inside of the cylindrical mold, for example, when the core of the resin roller is pulled in the axial direction of the resin roller and the resin roller is pulled out, the outer peripheral surface of the resin roller becomes You will be momentarily away from the inner surface of the mold. At this time, if liquid exists at the inlet or outlet of the cylindrical mold, the liquid instantaneously enters the gap between the outer peripheral surface of the molded body and the inner surface of the cylindrical mold by capillary action. Then, when the release load is continuously applied to the core of the resin roller in the axial direction of the resin roller, the resin roller is released from the cylindrical mold. At this time, a liquid is interposed between the outer peripheral surface of the resin roller and the inner surface of the cylindrical mold, and the liquid serves as a lubricant, and the resin roller is released without being rubbed.

Further, the present invention provides a method of manufacturing a resin roller, wherein the release of the resin roller is started in a liquid when the resin roller is released from the cylindrical mold. Immediately after starting the mold release, if the liquid instantaneously enters the gap between the outer peripheral surface of the molded body and the inner surface of the cylindrical mold by capillary action, the cylindrical mold and the molded body do not need liquid, for example, When the mold is released by immersion in a water tank, the cylindrical mold may be lifted into the air thereafter.

Further, according to the present invention, when the resin roller is released from the cylindrical mold, a liquid is sprayed, applied, and immersed in at least one of an inlet portion and an outlet portion in a removing direction of the cylindrical mold,
An object of the present invention is to provide a method for manufacturing a resin roller, which includes releasing.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings of a molding die and a core.

As shown in FIG. 2, the molding die 100 has a cylindrical die 13 and a pair of core holding members 14 arranged at both ends of the cylindrical die 13. 13 and a pair of core holding members 14 form a roller forming space 15. One of the core holding members 14 has the resin injection port 1.
6 are provided.

The molding die and the core of the present invention can be applied to any size of a known resin roller, but generally, the diameter is 10 mm to 30 mm and the length is 200 mm.
mm to 400 mm.

The cylindrical mold 13 and the core holding member 14
Is arbitrarily made of a known material used for thermosetting resin molding, and is preferably pre-hardened steel, hardened steel, non-magnetic steel, carbon tool steel, corrosion-resistant steel (stainless steel), or the like.

Inside the cylindrical mold 13, a core 21 of a resin roller to be inserted is held by a core holding member 14.

The molding method of the present invention using the core 21 and the configuration around the resin end will be described. For example, a polysiloxane-based curing agent and a conductivity-imparting material may be added to an allylated polyoxypropylene-based polymer. (Carbon black), and the roller outer diameter is φ
When a roller having a length of 16 mm and a molded body length of 250 mm is formed, the viscosity of the compounded injection resin is 200 to 800 poise, and the injection pressure at the time of injection is 0.2 to 800 poise, depending on the number of mixed parts of the conductive material. 5 MPa to 4 MPa. And
For example, in the case of a roller having the above dimensions and shape, when the thickness of the resin molded part is 4 mm, the diameter of the resin inlet of the mold is 1 mm to
mm.

The heating of the mold can be performed by any conventionally known method. Specifically, for example, a method of heating in a heating furnace provided with a heating fan, a method of arranging and heating an electric heater around a mold, or a method of arranging an induction heating coil around the mold and heating. There is a way.

As the temperature of the mold, any temperature at which the thermosetting resin can be injected and heat-cured can be selected. When the resin is injected, the temperature at which the resin is easily injected and which does not cure, For example, about 20 ° C. to 80 ° C. is preferable. Further, the heating temperature of the resin depends on the amount of the curing retarder incorporated into the resin, but is preferably about 80 ° C. to 200 ° C., and the heating time is preferably about 1 minute to 40 minutes.

After the curing of the resin is completed, each core holding member 14 is removed from the cylindrical mold 13 along the axial direction.

Next, for example, as shown in FIG. 3, the core body 21 of the resin roller is extruded into the cylindrical mold 13 in a water tank 31 filled with liquid by a release device 32 driven by an air cylinder or a motor. , Release.

For example, as shown in FIG. 4, the outlet of the vertically extending cylindrical mold in the drawing direction is immersed in a water tank 31 filled with liquid, and the mold is released in the same manner as described above.

Further, for example, a liquid is applied or sprayed to the inlet in the drawing direction of a cylindrical mold that is set up vertically as shown in FIG. 5, and the mold is released in the same manner as described above.

As for the liquid, pure water or distilled water, a solution obtained by adding a surfactant to them, or tap water or the like can be used from the viewpoint of cost if it contains no impurities. Can be used enough. If there is no problem in processing in the subsequent process or as a product, it is possible to select an oil having a low viscosity. In addition, since it is sufficient to act as a lubricant at the time of mold release, a volatile solvent such as alcohol can be used.

As a molding resin material usable in the molding method of the present invention, a thermosetting resin is used. For example, silicone, urethane, acrylonitrile / butadiene copolymer (NBR), ethylene / propylene / diene / methylene copolymer (EPDM) and the like can be used.

Various other additives can be added to the thermosetting resin as needed. For example, if a resistance control agent such as carbon is added, the electric resistance of the roller can be controlled.

As the thermosetting resin material, a curable composition described below can also be used. Since the molding resin composed of the reaction cured product of the curable composition has a particularly flexible structure,
Even if the thickness is reduced, the elastic effect is sufficiently exhibited. In addition, when containing an oxyalkylene unit, it is easy to handle because it has a low viscosity before curing, and when it contains a saturated hydrocarbon unit, it has a low water absorption and has little change in volume and roller resistance even in a high humidity environment. It is preferred in that respect. That is, as the thermosetting resin material, (A) a polymer having at least one alkenyl group in a molecule and a repeating unit constituting a main chain mainly consisting of an oxyalkylene unit or a saturated hydrocarbon unit; It is preferable to use a curing composition comprising (B) a curing agent having at least two hydrosilyl groups in a molecule, (C) a hydrosilylation catalyst, and (D) a conductivity-imparting agent.

If necessary, a material for adjusting the thermosetting reaction, such as a curing agent, a curing accelerator and a curing retarder, is added to the thermosetting resin. If necessary, an organic or inorganic filler can be added. Furthermore, various organic or inorganic pigments, thickeners, release agents, and the like can be added as necessary.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, non-limiting embodiments of the present invention will be described.

(Example) A roller having a roller outer diameter of φ16 mm and a resin molded portion having a length of 250 mm was formed using the mold shown in FIG.

The thermosetting resin material used was a compounded resin shown in Table 1 below and had a viscosity of 600 poise.

In a liquid resin injection and injection machine, the compounded resin material was injected at a pressure of 4 MPa, and the resin injection port of the die was set to a die with a diameter of 1.5 mm, and the longitudinal direction of the die was set vertically. It was injected from the bottom of the mold.

The heating of the mold is performed by heating in a heating furnace provided with a heating fan.
After setting the temperature to 0 ° C and heating for 20 minutes, removing the core holding member, a mold release load of 20 kg in the axial direction from the cylindrical mold to the resin roller core in a water tank filled with water at a water temperature of 20 ° C. The mold was released in about 10 seconds while applying a pressure to obtain a molded product.

As a result, no scratch was generated on the outer peripheral surface of the obtained resin roller due to friction with the inner surface of the cylindrical mold.

[0040]

[Table 1]

[0041]

According to the method of the present invention, a good product can be obtained stably at a low cost without abrasion on the outer peripheral surface of the resin roller, and the durability of the mold can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a general resin roller.

FIG. 2 is a general molding die and a peripheral view of the molding.

FIG. 3 is a cross-sectional view showing a state of a molded article releasing method according to one embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a state of a molded article releasing method according to one embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a state of a molded article releasing method according to one embodiment of the present invention.

DESCRIPTION OF SYMBOLS 10 Roller 12 Resin molding part 13 Cylindrical mold 14 Core holding member 15 Roller molding space 16 Inlet 18 Nozzle 19 Nozzle touch part 21 Core 31 Liquid tank 32 Release rod 33 Release rod drive source 34 cylindrical mold holding mechanism 35 liquid coating device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/08 501 G03G 15/08 501D 4F204 15/16 103 15/16 103 // B29K 101: 10 B29K 101 : 10 B29L 31:32 B29L 31:32 F term (reference) 2H003 BB11 CC05 2H032 AA05 BA23 2H077 AD06 DB12 DB14 DB15 FA13 3J103 AA02 AA13 AA32 EA02 EA13 EA20 FA09 FA15 GA02 GA52 GA57 GA58 GA60 GA74 HA03 HA42A47 AA42 AA43 AG03 AG14 AH04 CA01 CB01 CB12 CK43 CM90 CN05 CN13 CN24 CQ03 4F204 AA11 AB03 AB18 EA03 EB01 EK25

Claims (3)

[Claims] 1. A core is disposed in a molding die having a cylindrical mold and core holding members attached to both ends of the cylindrical mold, and both ends of the core are attached to the core. A method of manufacturing a resin roller by holding a holding member, injecting a resin into the mold, curing the molded article, and releasing the molded product from the inside of the cylindrical mold, comprising: A method for manufacturing a resin roller, comprising: starting and ending release in a liquid when releasing the roller. 2. A core is disposed in a molding die having a cylindrical mold and core holding members attached to both ends of the cylindrical mold, and both ends of the core are fixed to the core. A method of manufacturing a resin roller by holding a holding member, injecting a resin into the mold, curing the molded article, and releasing the molded product from the inside of the cylindrical mold, comprising: A method for manufacturing a resin roller, wherein the release of the roller is started in a liquid when the roller is released. 3. A core is disposed in a molding die having a cylindrical mold and core holding members attached to both ends of the cylindrical mold, and both ends of the core are fixed to the core. A method of manufacturing a resin roller by holding a holding member, injecting a resin into the mold, curing the molded article, and releasing the molded product from the inside of the cylindrical mold, comprising: A method for producing a resin roller, wherein a liquid is sprayed, applied, or immersed in at least one of an inlet and an outlet in a drawing direction of a cylindrical mold when releasing the roller, and the releasing is performed.