Manufacturing method for rubber product and manufacturing device for rubber product

Abstract

To provide a manufacturing method for a rubber product, which enables a rubber product having a complex shape to be molded as a shaped object.SOLUTION: A manufacturing method for a rubber product includes repeatedly carrying out a first molding step of molding a support material and an unvulcanized rubber composition on a specific plane, and a second molding step of molding a support material or an unvulcanized rubber composition on the support material or the unvulcanized rubber composition molded in the first molding step, thereby manufacturing the rubber product.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a rubber product and an apparatus for manufacturing a rubber product.

Background Art

[0002] Conventionally, a technique is known in which a material for a shaped object is deposited on a stage to form a layer, and a plurality of such layers are laminated to form a three-dimensional shaped object. In such a technique, when there is a portion that protrudes from the shaped object, a support is required to support this protruding portion from below. Patent Documents 1 and 2 disclose a technique in which a model material for forming a shaped object and a support material for forming the above-described support are deposited on a stage to form a three-dimensional shaped object.

[0003] Further, a technique is known in which a rubber product made of an unvulcanized rubber composition is shaped as a shaped object. Patent Document 3 discloses a technique for shaping a rubber-like object through a deposition step and a curing step. Patent Document 4 discloses that an unvulcanized rubber composition is stirred and mixed while being heated to a temperature below the vulcanization temperature in a screw extruder, and the unvulcanized rubber composition with low fluidity is laminated on a stage (shaping sheet) by discharging the unvulcanized rubber composition from a discharge hole, and a shaping apparatus for shaping a shaped object is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in order to shape a rubber product with a complex shape, such as a protruding portion, as a shaped article, it is desirable to use a support material. On the other hand, in the technology of shaping a rubber product as a shaped article, there has been no shaping method using a support material. Therefore, it has not been possible to shape a rubber product with a complex shape, such as a protruding portion, as a shaped article. It is known that a support material is likely to be required in order to shape a shaped article having a portion with an inclination angle greater than 45° with respect to the vertical direction. That is, it has been particularly difficult to shape a rubber product having a portion with an inclination angle greater than 45° with respect to the vertical direction.

[0006] One aspect of the present invention aims to provide a method for manufacturing a rubber product capable of shaping a rubber product with a complex shape as a shaped article.

Means for Solving the Problems

[0007] In order to solve the above problems, a method for manufacturing a rubber product according to one aspect of the present invention includes a first shaping step of shaping a support material and an unvulcanized rubber composition on a specific plane, and a second shaping step of shaping a support material or an unvulcanized rubber composition on the support material or the unvulcanized rubber composition shaped in the first shaping step, and repeating these steps to manufacture a rubber product.

[0008] In order to solve the above problems, a manufacturing apparatus for a rubber product according to one aspect of the present invention includes a first nozzle and a second nozzle. The first nozzle shapes an unvulcanized rubber composition on a specific plane and shapes an unvulcanized rubber composition on the unvulcanized rubber composition or the support material shaped on the specific plane. The second nozzle shapes a support material on the specific plane and shapes a support material on the unvulcanized rubber composition or the support material shaped on the specific plane.

Effects of the Invention

[0009] According to one aspect of the present invention, a method for manufacturing a rubber product capable of shaping a rubber product having a complex shape as a shaped article can be provided.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0011] 〔Embodiment 1〕 (Schematic Configuration of the Shaping Apparatus) FIG. 1 is a schematic diagram showing a shaping apparatus 100 for a rubber product RP according to an embodiment of the present invention. First, with reference to FIG. 1, the shaping apparatus 100 (manufacturing apparatus) for the rubber product RP will be described below.

[0012] As shown in FIG. 1, the shaping apparatus 100 includes a stage 2, a first nozzle 3, and a second nozzle 4. The shaping apparatus 100 manufactures a rubber product RP, which is a shaped article, by laminating a plurality of rubber layers RL containing an unvulcanized rubber composition on the surface of the stage 2 (see FIG. 2). Further, when there is a portion (overhanging portion) where the width of the upper position is larger than the width of the lower position of the rubber product RP, the shaping apparatus 100 produces a support S that supports the overhanging portion from below during the shaping of the rubber product RP. The shaping apparatus 100 produces the support S by laminating a support material on the surface of the stage 2 or the rubber layer RL.

[0013] Further, as shown in FIG. 1, the shaping device 100 includes a first nozzle driving device 13 and a second nozzle driving device 14 that drive the first nozzle 3 and the second nozzle 4, respectively. The shaping device 100 may include a first nozzle temperature control device 23 and a second nozzle temperature control device 24 for temperature control of the first nozzle 3 and the second nozzle 4, respectively. Further, the shaping device 100 includes a control device 15 that controls the first nozzle driving device 13 and the second nozzle driving device 14, respectively. The first nozzle temperature control device 23 includes an input means by which a user can set a target temperature, and controls a control target (a heater not shown in this embodiment) so that the unvulcanized rubber composition discharged from the first nozzle 3 reaches the target temperature based on a temperature sensor. The second nozzle temperature control device 24 includes an input means by which a user can set a target temperature, and controls a control target (a heater not shown in this embodiment) so that the support material discharged from the second nozzle 4 reaches the target temperature based on a temperature sensor.

[0014] The stage 2 defines an area (specific plane) where the unvulcanized rubber composition is laminated. The stage 2 is provided on the support base 21. The stage 2 is formed of a material that does not cause a chemical change with at least the unvulcanized rubber composition. For example, the stage 2 is a metal plate. The stage 2 may be heated by a heating device 22 (heater) built in the support base 21. The heating temperature by the heating device 22 is controlled by the control device 15.

[0015] The first nozzle 3 discharges an unvulcanized rubber composition as a model material from above the stage 2 toward the stage 2. When discharging the unvulcanized rubber composition, the first nozzle 3 is heated to a predetermined temperature at which the fluidity of the unvulcanized rubber composition becomes good by the first nozzle temperature control device 23. The unvulcanized rubber composition is vulcanized and cured by a predetermined curing treatment (for example, irradiation with ultraviolet rays) to form a rubber layer RL. By laminating the rubber layer RL, a rubber product RP is obtained.

[0016] The second nozzle 4 discharges the support material from above the stage 2 towards the stage 2. When discharging the support material, the second nozzle 4 is heated by the first nozzle temperature control device 23 to a predetermined temperature that improves the fluidity of the support material. The support material is cured by a predetermined curing treatment (for example, irradiation with ultraviolet rays) to form the support layer SL. When the support layer SL is laminated, it becomes the support S.

[0017] The first nozzle 3 and the second nozzle 4 are each moved along the surface of the stage 2 by the first nozzle driving device 13 and the second nozzle driving device 14 while discharging the uncured rubber composition. Thereby, the first nozzle 3 shapes the uncured rubber composition on a specific plane and shapes the uncured rubber composition on the uncured rubber composition or support material shaped on the specific plane (see Fig. 2). Further, the second nozzle 4 shapes the support material on a specific plane and shapes the support material on the uncured rubber composition or support material shaped on the specific plane (see Fig. 2). Hereinafter, when there is no need to particularly distinguish between the first nozzle 3 and the second nozzle 4, they are simply referred to as nozzles 3, 4.

[0018] The position, discharge timing, discharge amount, etc. of the nozzles 3, 4 may be controlled by the control device 15 according to the three-dimensional structure of the rubber product RP and the support S. Further, the stage 2 may move instead of the nozzles 3, 4. The stage 2 or the nozzles 3, 4 may move in the planar direction and the lamination direction. Either one of the stage 2 and the nozzles 3, 4 may move only in the planar direction, and either the other of the stage 2 and the nozzles 3, 4 may move in the lamination direction. Note that the planar direction means the direction in which the stage 2 or the nozzles 3, 4 move while keeping the distance between the nozzles 3, 4 and the stage 2 constant (the direction parallel to the surface of the stage 2). Also, the lamination direction means the direction in which the stage 2 or the nozzles 3, 4 approach and separate the stage 2 and the nozzles 3, 4 (the direction perpendicular to the surface of the stage).

[0019] (Regarding the uncured rubber composition and the support material) The unvulcanized rubber composition discharged from the first nozzle 3 is solid under normal temperature and pressure, and the support material discharged from the second nozzle 4 is preferably liquid under normal temperature and pressure. By shaping the unvulcanized rubber composition in a solid state while shaping the support material in a liquid state, the support material can be easily spread over a desired region on a specific plane. Therefore, the shaping position of the support material can be easily adjusted according to the shape, dimensions, etc. of the rubber product.

[0020] For example, the unvulcanized rubber composition discharged from the first nozzle 3 has the composition shown in Table 1. That is, the unvulcanized rubber composition discharged from the first nozzle 3 contains nitrile rubber (NBR) shaped by sulfur vulcanization. Note that the rubber base material contained in the unvulcanized rubber composition is not limited to these, and any material that can be vulcanized by heating may be used. For example, the rubber base material may be natural rubber or styrene-butadiene rubber shaped by sulfur vulcanization, acrylic rubber shaped by amine vulcanization, or silicone rubber shaped by peroxide vulcanization.

[0021]

Table 1

[0022] In addition, in order to obtain the rubber product RP, it is necessary to peel off the support S from the shaped article obtained by shaping the unvulcanized rubber composition and the support material. Here, depending on the combination of the unvulcanized rubber composition and the support material, when the unvulcanized rubber composition is vulcanized, the unvulcanized rubber composition may chemically react with the support material. As a result, it may become difficult to peel the shaped article obtained by shaping the unvulcanized rubber composition from the support obtained by shaping the support material. For example, when the rubber base material contained in the unvulcanized rubber composition and the support material are acrylic rubber and acrylic resin, silicone rubber and silicone resin, or fluororubber and EPDM rubber (ethylene-propylene-diene copolymer rubber), respectively, the unvulcanized rubber composition and the support material may chemically react with each other.

[0023] Therefore, the support material is configured so that the peelability of the support S with respect to the rubber product RP is good regardless of the composition of the unvulcanized rubber composition. Specifically, the support material may contain a peel promoting substance that improves the peelability of the support S obtained by shaping the support material with respect to the rubber product RP. By including the peel promoting substance in the support material, the peelability of the support S with respect to the rubber product RP can be made good regardless of the composition of the unvulcanized rubber composition. In other words, considering the peelability of the support S with respect to the rubber product RP, it is not necessary to select the composition of the support material with respect to the unvulcanized rubber composition, and the rubber product can be easily manufactured.

[0024] The peel promoting substance is preferably a substance having a solubility parameter of 40 (cal / cm 3 ) 1 / 2 or less. The following peel promoting substance does not mix with the main material of the support material (for example, PEG (polyethylene glycol)), and the support material becomes an emulsion. Therefore, the function of the peel promoting substance is easily exerted, and the peelability of the support S with respect to the rubber product RP can be improved. The solubility parameter of the peel promoting substance is preferably 10 to 40 (cal / cm 3 ) 1 / 2 or less. 3 )1 / 2 It is within the range. The release promoting substance is, for example, wax or oil.

[0025] Note that the configuration of the support material that provides good peelability of the support S from the rubber product RP is not limited to those described above. For example, a water-soluble material may be applied as the support material. Thereby, by immersing the shaped article in water, the support S can be easily peeled from the rubber product RP. Also, a material that can be deteriorated by ultraviolet rays may be applied as the support material. Thereby, by exposing the shaped article to ultraviolet rays, the support S can be easily peeled from the rubber product RP.

[0026] (Method for manufacturing a rubber product) FIG. 2 is a process diagram showing a method for manufacturing a rubber product RP. FIG. 3 is a flowchart showing a method for manufacturing a rubber product RP. Next, with reference to FIGS. 2 and 3, a method for manufacturing a rubber product RP by a shaping apparatus 100 will be described below. Hereinafter, the k-th rubber layer RL and the k-th support layer SL are respectively denoted as rubber layer RLk and support layer SLk (1 ≦ k ≦ n). Also, a plane formed by the surface of the rubber layer RLk and / or the surface of the support layer SLk is referred to as the k-th lamination plane Pk.

[0027] First, as shown by reference numeral 2001 in FIG. 2, the second nozzle 4 is disposed above the stage 2, and a support material is discharged from the discharge hole of the second nozzle 4 toward the stage 2. Here, the second nozzle 4 moves along the surface of the stage 2 (in the planar direction) as the support material is discharged. The second nozzle 4 moves, for example, in a circular motion, and joins the end of the unvulcanized rubber composition to the start of the unvulcanized rubber composition that was first discharged. Thereby, the support material is laminated on the surface of the stage 2 (S1 in FIG. 3). Specifically, the second nozzle 4 discharges the support material to a specific region on the surface of the stage 2 determined according to the three-dimensional structure of the support S (specifically, the cross-sectional shape corresponding to the support layer SL1 of the three-dimensional structure).

[0028] Next, as shown by reference numeral 2002 in FIG. 2, the first nozzle 3 is disposed above the stage 2, and the unvulcanized rubber composition is discharged from the discharge holes of the first nozzle 3 toward the stage 2. Similar to the second nozzle 4, the first nozzle 3 moves (in the planar direction) along the surface of the stage 2 as the unvulcanized rubber composition is discharged. Thereby, the unvulcanized rubber composition is laminated on the surface of the stage 2 (S2 in FIG. 3). Specifically, the first nozzle 3 discharges the unvulcanized rubber composition onto a specific region of the surface of the stage 2 determined according to the three-dimensional structure of the rubber product RP (specifically, the cross-sectional shape corresponding to the rubber layer RL1 of the three-dimensional structure).

[0029] Next, ultraviolet rays are irradiated onto the unvulcanized rubber composition and the support material laminated on the stage 2 (S3 in FIG. 3). Thereby, the unvulcanized rubber composition and the support material are cured to form layers. Accordingly, the unvulcanized rubber composition and the support material are shaped on the surface of the stage 2 as the rubber layer RL1 and the support layer SL1, respectively.

[0030] Next, since the shaping of the rubber product RP is not yet complete, the process returns to the lamination step S1 by the second nozzle 4 again (NO in S4 in FIG. 3). That is, as shown by reference numeral 2003 in FIG. 2, the second nozzle 4 is disposed above the stage 2, and the support material is discharged from the discharge holes of the second nozzle 4 toward the first lamination plane P1. Thereby, the support material is laminated on the first lamination plane P1 (S1 in FIG. 3). Specifically, the second nozzle 4 discharges the support material onto a specific region of the first lamination plane P1 determined according to the three-dimensional structure of the support S (specifically, the cross-sectional shape corresponding to the support layer SL2 of the three-dimensional structure). In an example shown in FIG. 2, the second nozzle 4 discharges the support material onto a part of the surface of the support layer SL1, and a part of the support layer SL1 is in an exposed state.

[0031] Next, as shown by reference numeral 2004 in FIG. 2, the first nozzle 3 is disposed above the stage 2, and the unvulcanized rubber composition is discharged from the discharge holes of the first nozzle 3 toward the first lamination plane P1. Thereby, the unvulcanized rubber composition is laminated on the first lamination plane P1 (S2 in FIG. 3). Note that the first nozzle 3 discharges the unvulcanized rubber composition to a specific region of the first lamination plane P1, which is determined according to the three-dimensional structure of the rubber product RP (specifically, the cross-sectional shape corresponding to the rubber layer RL2 of the three-dimensional structure). In an example shown in FIG. 2, the second nozzle 4 discharges the unvulcanized rubber composition to the surface of the rubber layer RL1 and the rest (exposed portion) of the surface of the support layer SL1.

[0032] Next, the unvulcanized rubber composition and the support material laminated on the first lamination plane P1 are irradiated with ultraviolet rays. Thereby, the unvulcanized rubber composition and the support material are cured to form layers (S3 in FIG. 3). Therefore, the unvulcanized rubber composition and the support material are shaped on the first lamination plane P1 as the rubber layer RL2 and the support layer SL2, respectively.

[0033] The above S1 to S3 are repeated until the shaping of the rubber product RP is completed. When the uppermost rubber layer Rn and the uppermost support layer SLn are formed, the shaping of the rubber product RP (and the support S) is completed (YES in S4 in FIG. 3). Next, the support S is peeled off from the rubber product RP whose shaping is completed (S5 in FIG. 3). Thereby, the rubber product RP is obtained.

[0034] Note that the support material may be shaped on the surface of the stage 2 or on any of the plurality of lamination planes according to the protruding portion of the rubber product RP. Further, in S1 and S2, after laminating the unvulcanized rubber composition, the support material may be laminated.

[0035] Summarizing the above, a first shaping step of shaping a support material and an unvulcanized rubber composition on a specific plane (either the surface of stage 2 or any of the plurality of laminated planes), and a second shaping step of shaping a support material or an unvulcanized rubber composition on the support material or unvulcanized rubber composition shaped in the first shaping step are repeatedly performed, whereby a rubber product RP is manufactured.

[0036] According to such a manufacturing method, by adjusting the shaping positions of the support material and the unvulcanized rubber composition in the first shaping step and the second shaping step according to the shape, dimensions, etc. of the rubber product RP to be manufactured, a desired rubber product can be manufactured. Therefore, for example, even a rubber product having a shape with a protruding portion in a cross-sectional view along the lamination direction and perpendicular to the planar direction can be manufactured by shaping a support material above or below the protruding portion. Note that the rubber product RP manufactured by this manufacturing method may be annular or linear with a pair of end portions.

[0037] Further, according to the above manufacturing method of laminating rubber layers in accordance with the three-dimensional structure of the rubber product RP, a mold becomes unnecessary. Therefore, in small-scale production, the manufacturing cost of the rubber product RP can be reduced. Also, since there is no need to cut a rubber block material, the rubber product RP can be manufactured at low cost and the environmental load can be suppressed.

[0038] Also, in at least one of the plurality of repeated first shaping steps and the second shaping steps, a part of the unvulcanized rubber composition may be shaped on the support material shaped in the immediately preceding shaping step. In an example shown by reference numeral 2004 in FIG. 2, the portion surrounded by the frame A of the unvulcanized rubber composition is shaped on the support material.

[0039] By shaping a part of the unvulcanized rubber composition on the support material, the protruding part of the rubber product RP can be formed while being supported by the support material. Then, after a plurality of repeated shaping steps, by removing the support obtained by shaping the support material from the rubber product, a rubber product RP having a protruding part can be appropriately manufactured even if it has a protruding part.

[0040] Note that there may be a shaping step of shaping a part of the support material on the support material. Furthermore, the support S may completely cover the rubber product RP as a shaped object.

[0041] 〔Example of Realization by Software〕 The functions of the control device 15 (hereinafter referred to as the "device") can be realized by a program for causing a computer to function as the device and a program for causing a computer to function as each control block of the device.

[0042] In this case, the above device includes a computer having at least one control device (for example, a processor) and at least one storage device (for example, a memory) as hardware for executing the above program. By executing the above program with this control device and storage device, each function described in each of the above embodiments is realized.

[0043] The above program may be recorded on one or more computer-readable recording media, not temporarily. This recording medium may or may not be provided in the above device. In the latter case, the above program may be supplied to the above device via any wired or wireless transmission medium.

[0044] Also, part or all of the functions of each of the above control blocks can also be realized by a logic circuit. For example, an integrated circuit in which a logic circuit functioning as each of the above control blocks is formed is also included in the scope of the present invention. In addition to this, for example, it is also possible to realize the functions of each of the above control blocks by a quantum computer.

[0045] 〔Summary〕 The manufacturing method of the rubber product according to Aspect 1 of the present invention includes a first shaping step of shaping a support material and an unvulcanized rubber composition on a specific plane, and a second shaping step of shaping a support material or an unvulcanized rubber composition on the support material or the unvulcanized rubber composition shaped in the first shaping step. By repeating these steps, a rubber product is manufactured.

[0046] In the manufacturing method according to Aspect 2 of the present invention, in the above Aspect 1, the unvulcanized rubber composition is solid at normal temperature and pressure, and the support material is liquid at normal temperature and pressure.

[0047] In the manufacturing method according to Aspect 3 of the present invention, in the above Aspect 2, the support material is the liquid resin.

[0048] In the manufacturing method according to Aspect 4 of the present invention, in any of the above Aspects 1 to 3, the support material contains a release promoting substance that improves the releasability of the support obtained by shaping the support material with respect to the rubber product.

[0049] In the manufacturing method according to Aspect 5 of the present invention, in the above Aspect 4, the solubility parameter of the release promoting substance is 40 (cal / cm 3 ) 1 / 2 or less.

[0050] The manufacturing method according to Aspect 6 of the present invention, in any of the above Aspects 1 to 5, among the plurality of repeated first shaping steps and second shaping steps, in at least one shaping step, a part of the unvulcanized rubber composition is shaped on the support material shaped in the immediately preceding shaping step.

[0051] The manufacturing apparatus for rubber products according to Aspect 7 of the present invention includes a first nozzle and a second nozzle. The first nozzle shapes an unvulcanized rubber composition on a specific plane, and shapes an unvulcanized rubber composition on the unvulcanized rubber composition or support material shaped on the specific plane. The second nozzle shapes a support material on the specific plane, and shapes a support material on the unvulcanized rubber composition or the support material shaped on the specific plane.

[0052] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims. For example, the unvulcanized rubber composition of the present invention is not limited to being solid under normal temperature and pressure, and may be liquid as long as it has a viscosity that can maintain its shape under normal temperature and pressure. Further, the support material does not necessarily have to contain a release promoting substance as long as it has a composition that can be peeled off from the support. Also, the first shaping step and the second shaping step do not necessarily have to be performed alternately. After performing the first shaping step a plurality of times, the second shaping step may be performed a plurality of times, and the steps may be repeated. Furthermore, the present invention also includes embodiments obtained by appropriately combining the technical means disclosed in different embodiments within the technical scope of the present invention.

Explanation of Signs

[0053] 3 First nozzle 4 Second nozzle 100 Shaping apparatus

Claims

1. A first shaping step of shaping a support material and an unvulcanized rubber composition on a specific plane, and a second shaping step of shaping a support material or an unvulcanized rubber composition on the support material or the unvulcanized rubber composition shaped in the first shaping step, are repeatedly performed to manufacture a rubber product. A method for manufacturing a rubber product, characterized in that.

2. The manufacturing method according to Claim 1, wherein the unvulcanized rubber composition is solid at normal temperature and normal pressure, and the support material is liquid at normal temperature and normal pressure.

3. The manufacturing method according to Claim 2, wherein the support material is a liquid resin.

4. The manufacturing method according to Claim 1, wherein the support material contains a peeling promoting substance that improves the peelability of the support obtained by shaping the support material with respect to the rubber product.

5. The solubility parameter of the peeling promoter is 40 (cal / cm ３ ). １／２ The production method according to claim 4, wherein the solubility parameter is 40 (cal / cm ３ ).

6. Among the plurality of repeated first shaping steps and second shaping steps, in at least one shaping step, a part of the unvulcanized rubber composition is shaped on the support material shaped in the immediately preceding shaping step. The manufacturing method according to Claim 1, characterized in that.

7. Comprising a first nozzle and a second nozzle, The first nozzle shapes an unvulcanized rubber composition on a specific plane, and shapes an unvulcanized rubber composition on the unvulcanized rubber composition or the support material shaped on the specific plane. The second nozzle shapes a support material on the specific plane, and shapes a support material on the unvulcanized rubber composition or the support material shaped on the specific plane. A manufacturing apparatus for a rubber product.

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