JP6702220B2 - Sheet molding compound manufacturing method - Google Patents

Description

  The present invention relates to a method of manufacturing a sheet molding compound.

  2. Description of the Related Art Conventionally, there is known a method for producing a sheet molding compound that has predetermined mechanical properties, is lightweight, is thin, and has excellent smoothness on at least one side (see Patent Document 1 below). In the conventional manufacturing method described in Patent Document 1, first, a curable resin composition containing a low-shrinking agent is uniformly applied to one surface of a separate film to form a resin layer, and chopped reinforcing fibers are further formed on the resin layer. Sprinkle on. Then, a curable resin composition that does not substantially contain a low-shrinking agent is uniformly applied to one surface of another separate film to form a resin layer, and the resin layer surface sprinkled with chopped reinforcing fibers and the latter resin layer. Overlap with the surface. Thereafter, pressure is applied from the outside to press the two together to impregnate the chopped reinforcing fiber with the resin composition.

JP 2004-35714A

  In the conventional method for manufacturing a sheet molding compound, a curable resin composition containing a low-shrinking agent is applied to one surface of a separate film to form a resin layer. Therefore, the low shrinkage agent contained in the curable resin composition may be separated or condensed due to factors such as a difference in specific gravity and compatibility between the curable resin composition and the low shrinkage agent.

  The present invention has been made in view of the above problems, and a sheet molding compound capable of suppressing the shrinkage of the thermosetting resin and reducing the warp without adding a low-shrinking agent to the thermosetting resin ( It is an object of the present invention to provide a method for manufacturing SMC).

  In order to achieve the above object, a method of manufacturing a sheet molding compound according to the present invention includes a first fiber spraying step of spraying cut first reinforcing fibers on a first paste of thermosetting resin, and the first paste. A method of manufacturing a sheet molding compound, comprising: a first resin impregnation step of impregnating the first reinforcing fibers with a resin; and a resin curing step of heating and curing the first paste impregnated with the first reinforcing fibers. Then, before the first resin impregnation step, there is a low shrinkage material laminating step of laminating a film-shaped low shrinkage material on the first paste.

  The first fiber spraying step is, for example, a step of spraying the first reinforcing fibers cut into a predetermined length on the first paste of the thermosetting resin. The present manufacturing method may include a first release material supplying step and a first resin laminating step before the first fiber spraying step. The first fiber spraying step can be performed on the first paste laminated on the first mold release material, for example, through the first mold release agent supplying step and the first resin laminating step. ..

  The first release material supplying step is a step of supplying the first release material by, for example, unwinding a film-shaped first release material wound in a roll shape and transporting it by a roller. The first resin laminating step is, for example, a step of laminating the first paste on the first release material. More specifically, the first resin laminating step is a first resin applying step of applying the first paste on the first release material.

  The first resin impregnation step is, for example, a step of impregnating the first paste with the first paste by applying pressure to the first paste with an impregnation roll. The impregnating rolls are arranged, for example, opposite to each other in the thickness direction of the laminate of the material forming the sheet molding compound containing the first paste. The impregnating roll applies pressure to the first paste to impregnate the first reinforcing fibers by sandwiching the laminate from both sides in the thickness direction while rotating to feed the laminate in the feeding direction, for example. .. Thereby, the sheet molding compound can be manufactured.

  The resin curing step is a step of heating and curing the first paste impregnated in the first reinforcing fibers. This resin curing step is, for example, a step of hot press molding the sheet molding compound obtained in the first resin impregnation step. In this case, one sheet molding compound may be hot-press molded, or a plurality of sheet molding compounds may be laminated and hot-press molded. The first paste of the thermosetting resin heated in the resin curing step cures and tries to shrink. In this manufacturing method, this resin curing step is performed after the low shrinkage material laminating step.

  The low shrinkage material laminating step is, for example, a step of laminating a film-shaped low shrinkage material on the first paste before the first resin impregnation step. In this low-shrinkage material laminating step, for example, a film-shaped low-shrinkage material wound in a roll shape is unwound and conveyed by a roller, so that the low-shrinkage material is supplied to be laminated on the first paste. It is a process to do.

  The low shrinkage material laminating step can be performed, for example, before or after the first fiber spraying step. When this low shrinkage material laminating step is a step before the first fiber spraying step, the low shrinkage material is directly laminated on the first paste. When the low shrinkage material laminating step is a step subsequent to the first fiber spraying step, the low shrinkage material is laminated on the first paste via the first reinforcing fibers.

  Thus, in the low-shrinkage material laminating step, by laminating the film-shaped low-shrinkage material on the first paste, the shrinkage of the first paste is suppressed by the low-shrinkage material in the resin curing step. As a result, the warp of the sheet molding compound can be reduced. The heat shrinkage rate of the low shrinkage material is lower than the heat shrinkage rate of the first paste. Here, the thermal contraction rate means the rate of contraction that occurs in an object when the temperature of the object rises by 1°C.

  More specifically, the low-shrinkage material heated in the resin curing step does not melt as a whole, but the surface portion melts to be compatible with the thermosetting resin or the reinforced fiber, and the thermosetting resin or the reinforced resin. The wettability of the fiber is improved. Therefore, in the sheet molding compound and the molded article manufactured by the present manufacturing method, the presence of the crystalline layer of the low-shrinkage material suppresses the curing shrinkage of the thermosetting resin on the entire surface and reduces the warpage.

  The present manufacturing method includes, for example, the low shrink material laminating step after the first fiber spraying step, and the second resin laminating step after the low shrink material laminating step and before the first resin impregnating step. You may. This second resin laminating step is, for example, a step of laminating a second paste of thermosetting resin on the low shrinkage material. In this case, the present manufacturing method may include a second release material supplying step and a second resin applying step before the second resin laminating step.

  The second release material supplying step is a step of supplying the second release material by, for example, unwinding a film-shaped second release material wound in a roll shape and transporting it by a roller. The second resin applying step is, for example, a step of applying a second paste of a thermosetting resin on the second release material. In this case, the second resin laminating step is, for example, a step of laminating the second release material coated with the second paste on the low shrinkage material.

  The first resin impregnation step may be provided after the second resin laminating step. Thereby, the sheet molding compound can be manufactured. Here, when the low shrinkage material laminating step is a step before the first fiber spraying step, the second release material impregnated with the first release material, the first paste, the low shrinkage material, and the first reinforcing fiber is used. It is possible to manufacture a sheet molding compound in which the paste and the second release material are laminated in this order.

  On the other hand, when the low-shrinkage material laminating step is a post-step of the first fiber spraying step, the first release material, the first paste impregnated with the first reinforcing fibers, the low-shrinkage material, and the second paste , And the second release material can be laminated in this order to manufacture a sheet molding compound. Further, by including the resin curing step after the first resin impregnation step, it is possible to manufacture a molded product using one layer of the sheet molding compound or a multilayer molded product using the sheet molding compound.

  In addition, the present manufacturing method may be, for example, a second resin lamination in which a second paste of a thermosetting resin is laminated on the first paste on which the first reinforcing fibers are dispersed after the first fiber dispersing step. You may have a process. More specifically, the second resin laminating step is a second resin applying step of applying a second paste of a thermosetting resin onto the first paste on which the first reinforcing fibers are dispersed.

  In this case, the present manufacturing method may include the low-shrinkage material laminating step and the first resin impregnating step after the second resin laminating step. Here, in the first resin impregnation step, for example, the first paste and the second paste are impregnated into the first reinforcing fibers by applying pressure to the first paste and the second paste with an impregnation roll. It is a process.

  The impregnating rolls are arranged, for example, opposite to each other in the thickness direction of the laminate of the material forming the sheet molding compound containing the first paste and the second paste. The impregnating roll applies pressure to the first paste and the second paste, for example, by sandwiching the laminate from both sides in the thickness direction while rotating to feed the laminate in the feeding direction, and these are treated as described above. Impregnate the first reinforcing fiber. This can improve the wettability of the first paste and the second paste with respect to the first reinforcing fiber.

  In this case, the present manufacturing method includes a third resin laminating step, a second fiber spraying step, a fourth resin laminating step, and a second resin impregnating step after the first resin impregnating step and before the resin curing step. And a process. The third resin laminating step is, for example, a step of laminating a third paste of thermosetting resin on the low shrinkage material. More specifically, the third resin laminating step is a third resin applying step of applying the third paste on the low shrinkage material.

  The second fiber spraying step is, for example, a step of spraying the second reinforcing fibers cut into a predetermined length on the third paste. Thus, when the present manufacturing method has a plurality of fiber spraying steps, it becomes possible to reduce the amount of reinforcing fiber per layer and improve the wettability of the paste of the thermosetting resin to the reinforcing fiber. be able to.

  The fourth resin laminating step is, for example, a step of laminating a fourth paste of thermosetting resin on the third paste on which the second reinforcing fibers are dispersed. In this case, the present manufacturing method may include a second release material supplying step and a fourth resin applying step before the fourth resin laminating step.

  The second release material supplying step is a step of supplying the second release material by, for example, unwinding a film-shaped second release material wound in a roll shape and transporting it by a roller. The fourth resin application step is, for example, a step of applying a fourth paste of thermosetting resin onto the second release material. In this case, the fourth resin laminating step is, for example, a step of laminating the second release material coated with the fourth paste on the third paste on which the second reinforcing fibers are dispersed.

  The second resin impregnation step may be provided after the fourth resin laminating step. Here, in the second resin impregnation step, for example, the third paste and the fourth paste are impregnated into the second reinforcing fibers by applying pressure to the third paste and the fourth paste with an impregnation roll. It is a process. The impregnating rolls are arranged, for example, opposite to each other in the thickness direction of the laminate of the material forming the sheet molding compound containing the third paste and the fourth paste.

  The impregnating roll applies pressure to the third paste and the fourth paste by sandwiching the laminate from both sides in the thickness direction while rotating to feed the laminate in the feeding direction, for example. The second reinforcing fiber is impregnated. In the second resin impregnation step, pressure may be applied to the first paste and the second paste to further impregnate the first reinforcing fiber with the first paste and the second paste. ..

  Thereby, the sheet molding compound can be manufactured. The sheet molding compound thus manufactured includes a first mold release material, the first paste and the second paste impregnated with the first reinforcing fibers, the low shrinkage material, and the second reinforcing fibers. The third paste, the fourth paste, and the second release material form a laminated body that is laminated in this order. As described above, since the resin impregnation step is performed a plurality of times, the impregnation property of the thermosetting resin into the reinforcing fiber is improved, and delamination can be prevented.

  In addition, by including the resin curing step after the second resin impregnation step, it is possible to manufacture a molded product using one layer of the sheet molding compound or a molded product using multiple layers of the sheet molding compound. At this time, as described above, by stacking the low shrink material in the low shrink material laminating step, shrinkage from the first paste to the fourth paste is suppressed by the low shrink material, and the sheet molding compound The warp can be reduced. Further, in the low shrinkage material laminating step, since the low shrinkage material is laminated on the sheet molding compound, it is not necessary to add a low shrinkage agent to the thermosetting resin paste laminated in each resin laminating step. Absent.

  The method for producing a sheet molding compound of the present invention has a low-shrinkage material laminating step of laminating a film-shaped low-shrinkage material on a paste of thermosetting resin or reinforcing fibers scattered on the paste. .. Therefore, in the curing step of heating and curing the thermosetting resin paste, the film-shaped low-shrinking material suppresses the curing shrinkage of the thermosetting resin, without adding a low-shrinking agent to the thermosetting resin. It is possible to reduce the warp of the sheet molding compound.

The schematic sectional drawing which shows an example of a sheet molding compound (SMC). FIG. 3 is a flowchart showing the method of manufacturing the SMC according to the first embodiment of the present invention. Schematic which shows an example of the manufacturing apparatus for implementing the manufacturing method of SMC shown in FIG. The schematic sectional drawing which shows an example of SMC. FIG. 6 is a flowchart showing a method for manufacturing an SMC according to the second embodiment of the present invention. Schematic which shows an example of the manufacturing apparatus for enforcing the manufacturing method of SMC shown in FIG.

  Hereinafter, an embodiment of a method for manufacturing a sheet molding compound of the present invention will be described with reference to the drawings. Hereinafter, the sheet molding compound is abbreviated as "SMC".

[Embodiment 1]
FIG. 1 is a schematic cross-sectional view showing an example of an SMC 10 manufactured by the SMC manufacturing method according to the first embodiment of the present invention. The SMC 10 is, for example, a molding material in which a reinforcing fiber is impregnated with a thermosetting resin paste as a matrix and is molded into a sheet having a thickness of about several mm. The SMC 10 includes, for example, a first release material 11, a first paste 13 of thermosetting resin impregnated in the first reinforcing fibers 12, a low shrinkage material 14, a second paste 15 of thermosetting resin, and The second release material 16 is a laminated body laminated in this order.

  As the first paste 13 and the second paste 15 which are thermosetting resin pastes, for example, a low-shrinking agent is not added, or the addition amount of the low-shrinking agent is significantly reduced as compared with the conventional one. An unsaturated polyester resin or the like can be used. The first paste 13 and the second paste 15 can include various additives such as a curing agent, a curing catalyst, a release agent, a thickener, a coloring agent, and a filler, for example.

  As the first reinforcing fiber 12 that is the reinforcing fiber, for example, carbon fiber, graphite fiber, boron fiber, glass fiber, or the like cut into a predetermined length can be used. Since carbon fiber is lighter than other fibers, it is most suitable as a reinforcing fiber for manufacturing a thin and lightweight SMC. As the first reinforcing fiber 12, for example, one cut into a length of about 1 [in] can be used.

  As the first release material 11 and the second release material 16, for example, a resin film such as a PET film laminated with silicone, a fluororesin film, or a polyolefin resin film, or a resin film coated with a polyolefin-based coating agent is used. You can

  As the film-shaped low-shrinkage material 14, a stretched film is preferable because it is heat-fixed and crystallized, and the heat-shrinkage is small. As a material of the low-shrinkage material 14, a polyolefin resin or a polyester resin can be used. As the polyolefin resin, for example, polyethylene (PE), polypropylene (PP) or the like can be used, and as the polyester resin, for example, polyethylene terephthalate (PET), polylactic acid (PLA resin) or the like can be used. .

  FIG. 2 is a flow chart of the SMC manufacturing method S100 of the present embodiment. FIG. 3 is a schematic diagram showing an example of a manufacturing apparatus E1 for carrying out the SMC manufacturing method S100 shown in FIG. The SMC manufacturing method S100 of the present embodiment includes a first fiber spraying step S103, a first resin impregnation step S108, and a resin curing step S109, and a low shrinkage material laminating step before the first resin impregnation step S108. It is characterized by having S104.

  Further, the SMC manufacturing method S100 of the present embodiment has a first release material supplying step S101 and a first resin laminating step S102 before the first fiber spraying step S103, and after the first fiber spraying step S103. The low shrinkage material laminating step S104. Further, after the low shrinkage material laminating step S104, before the first resin impregnation step S108, there is a second resin laminating step S107, and before the second resin laminating step S107, a second release material supplying step S105 and It has the 2nd resin application process S106. Hereinafter, each of these steps will be described in detail.

  In the first release material supplying step S101, as shown in FIG. 3, for example, by unwinding the film-shaped first release material 11 wound in a roll shape and conveying it by a roller (not shown), This is a step of supplying the release material 11. As shown in FIG. 2, after the first mold release material supplying step S101, a first resin laminating step S102 is performed.

  In the first resin laminating step S102, as shown in FIG. 3, for example, the above-mentioned first paste 13 of thermosetting resin is laminated on the first mold releasing material 11 supplied in the first mold releasing material supplying step S101. It is a process to do. More specifically, the first resin laminating step S102 is a first resin applying step of applying the first paste 13 on the film-shaped first release material 11. The first paste 13 is uniformly applied onto the first release material 11 by a doctor blade (not shown), for example. As shown in FIG. 2, after the first resin laminating step S102, a first fiber spraying step S103 is performed.

  In the first fiber spraying step S103, as shown in FIG. 3, for example, the first reinforcing fibers cut on the first paste 13 of thermosetting resin into a predetermined length by a cutting device such as a roving cutter C. It is a process of spraying 12. As described above, in the SMC manufacturing method of the present embodiment, the first fiber spraying step S103 is laminated on the first mold release material 11 through the first mold release material supplying step S101 and the first resin laminating step S102. It is performed on the first paste 13. As shown in FIG. 2, after the first fiber spraying step S103, a low shrinkage material laminating step S104 is performed.

  As shown in FIG. 3, the low shrinkage material stacking step S104 is a step of stacking the filmy low shrinkage material 14 on the first paste 13 on which the first reinforcing fibers 12 are dispersed, for example. More specifically, in the low-shrinkage material laminating step S104, for example, the low-shrinkage material 14 is unwound by rolling out a film-shaped low-shrinkage material 14 and conveyed by rollers (not shown). It is a step of stacking on the first paste 13 on which the first reinforcing fibers 12 are supplied and sprinkled.

  As a result, the first reinforcing fibers 12 and the first paste 13 are sandwiched between the first release material 11 and the low shrinkage material 14. As shown in FIG. 2, after the low-shrinkage material laminating step S104, the second resin laminating step S107 is performed, but in the SMC manufacturing method S100 of the present embodiment, before that, the second release material supplying step is performed. S105 and the second resin coating step S106 are performed.

  In the second release material supplying step S105, as shown in FIG. 3, for example, similarly to the first release material 11 described above, the film-shaped second release material 16 wound into a roll is unwound to roll the roller R. Is a step of supplying the second release material 16 by carrying the second release material 16. In the second resin applying step S106, as shown in FIG. 3, for example, the second paste 15 of the thermosetting resin is formed on the second mold release material 16 similarly to the first paste 13 of the thermosetting resin described above. Is a step of applying.

  As shown in FIG. 2, the second mold release material supplying step S105 and the second resin coating step S106 can be performed in parallel with the first mold releasing material supplying step S101 to the low shrinkage material laminating step S104. As a result, the manufacturing process and manufacturing line can be shortened. After the low shrinkage material laminating step S104 and the second resin applying step S106, a second resin laminating step S107 is performed.

  The second resin laminating step S107 is, for example, a step of laminating a second paste 15 of a thermosetting resin on the low shrinkage material 14, as shown in FIG. More specifically, in the SMC manufacturing method S100 of the present embodiment, in the second resin laminating step S107, for example, the second mold release material 16 coated with the second paste 15 is laminated on the low shrinkage material 14. It is a process. As a result, the second paste 15 and the second release material 16 can be simultaneously laminated on the low shrinkage material 14. As shown in FIG. 2, after the second resin laminating step S107, the first resin impregnating step S108 is performed.

  In the first resin impregnation step S108, as shown in FIG. 3, for example, pressure is applied to the first paste 13 by the impregnation roll IR, so that the first paste 13 is interposed between the first release material 11 and the low shrinkage material 14. Is a step of impregnating the first reinforcing fiber 12. The impregnating rolls IR are arranged, for example, so as to face each other on both sides in the thickness direction of the laminated body 10a of the material forming the SMC 10 including the first paste 13.

  The impregnating roll IR is, for example, rotated to feed the laminated body 10a in the feeding direction F, and sandwiches the laminated body 10a from both sides in the thickness direction, thereby applying a pressure to the first paste 13 to apply the first reinforcing fiber. Impregnate 12 As a result, the SMC 10 shown in FIG. 1 can be manufactured. As shown in FIG. 2, a resin curing step S109 is performed subsequent to the first resin impregnation step S108.

  The resin curing step S109 is a step of heating and curing the first paste 13 impregnated in the first reinforcing fibers 12. The resin curing step S109 is, for example, a step of hot pressing the SMC 10 obtained in the first resin impregnation step S108. In this case, one SMC 10 may be hot press molded, or a plurality of SMCs 10 may be laminated and hot press molded. The first paste 13 and the second paste 15 of the thermosetting resin heated in this resin curing step S109 harden and shrink.

  However, in the SMC manufacturing method S100 of the present embodiment, as described above, the film-shaped low-shrink material 14 is stacked on the first paste 13 in the low-shrink material stacking step S104. Therefore, in the resin curing step S109, the shrinkage of the first paste 13 is suppressed by the low shrinkage material 14, and the warp of the SMC 10 can be reduced. The heat shrinkage rate of the low shrinkage material 14 is lower than the heat shrinkage rates of the first paste 13 and the second paste 15 of the thermosetting resin. Here, the thermal contraction rate means the rate of contraction that occurs in an object when the temperature of the object rises by 1°C.

  More specifically, the low-shrinkage material 14 heated in the resin curing step S109 does not melt entirely, but the surface portion melts and becomes compatible with the thermosetting resin and the reinforcing fiber, and The wettability of the fiber is improved. Therefore, in the SMC 10 and the molded article manufactured by the SMC manufacturing method S100 of the present embodiment, the presence of the crystal layer of the low-shrinkage material 14 suppresses the hardening shrinkage of the thermosetting resin on the entire surface and reduces the warp. To be done.

  In the resin curing step S109, a single-layer SMC 10 can be hot press-molded to form a molded product made of a single layer SMC 10. Further, in the resin curing step S109, a plurality of SMCs 10 are stacked and hot press-molded to form a molded product including the multilayered SMCs 10. In any case, since the crystal layer of the low-shrinkage material 14 is present, the hardening of the thermosetting resin is suppressed on the entire shrinking surface, and the warpage of the molded product is reduced.

  In the resin curing step S109, the low shrinkage material 14 reduces the difference in the amount of material shrinkage that occurs on the front surface side and the back surface side of the molded product due to the temperature difference between the upper mold and the lower mold of the press mold, for example. In-plane waviness and warpage of the entire molded product can be suppressed. Further, in the resin curing step S109, the shrinkage difference caused in the cooling process due to the difference in the linear expansion coefficient between the thermosetting resin and the reinforcing fiber is reduced by the low shrinkage material 14, and the warpage or deformation of the molded product is suppressed. be able to.

  As described above, the SMC manufacturing method S100 of the present embodiment is a low shrinkage material in which the film-shaped low shrinkage material 14 is laminated on the thermosetting resin paste or the reinforcing fibers scattered on the paste. It has a laminating step S104. Therefore, in the curing step in which the thermosetting resin paste is heated and cured, the film-shaped low shrinkage material 14 suppresses the curing shrinkage of the thermosetting resin, and the low shrinkage agent is added to the thermosetting resin. Therefore, the warp of the SMC 10 can be reduced.

  In the SMC manufacturing method S100 of the present embodiment, an example in which the low shrinkage material laminating step S104 is performed after the first fiber spraying step S103 has been described. You may go before. In this case, in the low shrinkage material laminating step S104, the low shrinkage material 14 is directly laminated on the first paste 13, and then the first fiber spraying step S103 is performed to perform the first shrinkage material 14 first. The reinforcing fibers 12 can be sprinkled, and then the second resin laminating step S107 can be performed.

  Alternatively, after the second resin applying step S106, the first fiber spraying step S103 may be performed to spray the first reinforcing fibers 12 on the second paste 15, and then the second resin laminating step S107 may be performed. .. As described above, when the low shrinkage material laminating step S104 is performed before the first fiber spraying step S103, the first mold release material 11, the first paste 13, the low shrinkage material 14, and the second reinforcing material 12 impregnated with the second An SMC in which the paste 15 and the second release material 16 are laminated in this order can be manufactured.

[Embodiment 2]
Next, a second embodiment of the SMC manufacturing method of the present invention will be described. FIG. 4 is a schematic sectional view showing an example of the SMC 20 manufactured by the SMC manufacturing method according to the second embodiment of the present invention. The SMC 20 includes, for example, a first release material 21, a first paste 23 and a second paste 24 of a thermosetting resin impregnated in a first reinforcing fiber 22, a low shrinkage material 25, and a second reinforcing fiber 26. The third paste 27 and the fourth paste 28 of the impregnated thermosetting resin, and the second release material 29 are laminated in this order.

  In the SMC 20 shown in FIG. 4, the first release material 21 and the second release material 29, the first reinforcing fibers 22 and the second reinforcing fibers 26, the first paste 23 to the fourth paste 28 of the thermosetting resin, and the low shrinkage material. Reference numeral 25 denotes the first mold release material 11 and the second mold release material 16, the first reinforcing fiber 12, the first paste 13 and the second paste 15 of the thermosetting resin, and the low shrinkage material 14 in the SMC 10 shown in FIG. 1, respectively. The same as can be used.

  FIG. 5 is a flow chart of the SMC manufacturing method S200 of the present embodiment. FIG. 6 is a schematic diagram showing an example of a manufacturing apparatus E2 for carrying out the SMC manufacturing method S200 shown in FIG. The SMC manufacturing method S200 of the present embodiment has a first fiber spraying step S203, a first resin impregnation step S206, and a resin curing step S213, similar to the SMC manufacturing method S100 of the first embodiment described above. The low shrinkage material laminating step S205 is provided before the first resin impregnation step S206.

  Further, in the SMC manufacturing method S200 of the present embodiment, as shown in FIG. 5, for example, before the first fiber spraying step S203, the first mold release material supplying step S201 and the first mold release material supplying step S201 similar to those of the first embodiment are performed. It has a resin laminating step S202. Similar to the first embodiment, the first release material supplying step S201 is a step of supplying the first release material 21 shown in FIG. 6, and the first resin laminating step S202 is performed on the first release material 21. It is a step of laminating the first paste 23 of a thermoplastic resin. The first fiber spraying step S203 is a step of spraying the cut first reinforcing fibers 22 on the first paste 23.

  Further, as shown in FIG. 5, the SMC manufacturing method S200 of the present embodiment has a second resin laminating step S204 after the first fiber spraying step S203, for example. The second resin laminating step S204 is a step of laminating the second paste 24 of thermosetting resin on the first paste 23 on which the first reinforcing fibers 22 are dispersed, as shown in FIG. More specifically, the second resin laminating step S204 is a second resin applying step of applying the second paste 24 of the thermosetting resin on the first paste 23 on which the first reinforcing fibers 22 are dispersed. ..

  Further, as shown in FIG. 5, the SMC manufacturing method S200 of the present embodiment includes a low shrinkage material laminating step S205 and a first resin impregnating step S206 after the second resin laminating step S204. The low shrinkage material stacking step S205 is a step of supplying the low shrinkage material 25 and stacking the low shrinkage material 25 on the second paste 24, as in the method S100 of manufacturing the SMC of the first embodiment. In the first resin impregnation step S206, as shown in FIG. 6, for example, pressure is applied to the first paste 23 and the second paste 24 by the impregnation roll IR1 to first strengthen the first paste 23 and the second paste 24. This is the step of impregnating the fibers 22.

  The impregnating rolls IR1 are arranged, for example, opposite to each other on both sides in the thickness direction of the laminated body 20a of the material forming the SMC 20 including the first paste 23 and the second paste 24. The impregnating roll IR1 applies pressure to the first paste 23 and the second paste 24 by sandwiching the laminated body 20a from both sides in the thickness direction while rotating the laminated body 20a to feed it in the feeding direction F, for example. Are impregnated in the first reinforcing fiber 22. Thereby, the wettability of the first paste 23 and the second paste 24 with respect to the first reinforcing fibers 22 can be improved.

  In addition, as shown in FIG. 5, the SMC manufacturing method S200 of the present embodiment includes a third resin laminating step S207 and a second fiber spraying step after the first resin impregnating step S206 and before the resin curing step S213. It has S208, a fourth resin laminating step S211, and a second resin impregnating step S212. As shown in FIG. 6, the third resin laminating step S207 is a step of laminating a third paste 27 of thermosetting resin on the low shrinkage material 25, for example. More specifically, the third resin laminating step S207 is a third resin applying step of applying the third paste 27 on the low shrinkage material 25.

  The second fiber spraying step S208 is, for example, a step of spraying the second reinforcing fibers 26 cut into a predetermined length on the third paste 27, as shown in FIG. As described above, when the fiber spraying step is performed a plurality of times, it is possible to reduce the amount of the reinforcing fiber per layer and improve the wettability of the thermosetting resin paste to the reinforcing fiber.

  As shown in FIG. 6, the fourth resin laminating step S211 is a step of laminating the fourth paste 28 of the thermosetting resin on the third paste 27 on which the second reinforcing fibers 26 are dispersed, for example. Here, as shown in FIG. 5, the SMC manufacturing method S200 of the present embodiment includes a second release material supplying step S209 and a fourth resin applying step S210 before the fourth resin laminating step S211. There is.

  In the second release material supplying step S209, as in the SMC manufacturing method S100 of the first embodiment described above, as shown in FIG. 6, for example, the film-shaped second release material 29 wound in a roll shape is wound. In this step, the second release material 29 is supplied by taking it out and carrying it by the roller R. As shown in FIG. 6, the fourth resin applying step S210 is a step of applying, for example, the fourth paste 28 of the thermosetting resin on the second release material 29.

  As shown in FIG. 5, the second mold release material supplying step S209 and the fourth resin applying step S210 may be performed in parallel with the above-mentioned first mold releasing material supplying step S201 to the second fiber spraying step S208. it can. This makes it possible to shorten the manufacturing process and the manufacturing line. After the second fiber spraying step S208 and the fourth resin applying step S210, a fourth resin laminating step S211 is performed.

  In the SMC manufacturing method S200 of the present embodiment, in the fourth resin laminating step S211, as shown in FIG. 6, for example, the fourth paste 28 is formed on the third paste 27 on which the second reinforcing fibers 26 are dispersed. This is a step of stacking the applied second release material 29. As a result, the fourth paste 28 and the second release material 29 can be simultaneously laminated on the third paste 27 on which the second reinforcing fibers 26 are dispersed. As shown in FIG. 5, after the fourth resin laminating step S211, a second resin impregnating step S212 is performed.

  In the second resin impregnation step S212, as shown in FIG. 6, for example, pressure is applied to the third paste 27 and the fourth paste 28 by the impregnating roll IR2 to second strengthen the third paste 27 and the fourth paste 28. This is the step of impregnating the fibers 26. The impregnating rolls IR2 are arranged, for example, opposite to each other on both sides in the thickness direction of the laminated body 20b of the material forming the SMC 20 including the third paste 27 and the fourth paste 28.

  The impregnation roll IR2 applies pressure to the third paste 27 and the fourth paste 28 by sandwiching the laminate 20b from both sides in the thickness direction while rotating to feed the laminate 20b in the feed direction F, for example. Are impregnated in the second reinforcing fiber 26. In the second resin impregnation step S212, pressure may be applied to the first paste 23 and the second paste 24 to further advance the impregnation of the first paste 23 and the second paste 24 into the first reinforcing fiber 22. it can. As a result, the SMC 20 shown in FIG. 4 can be manufactured. As described above, since the resin impregnation step is performed a plurality of times, the impregnation property of the thermosetting resin into the reinforcing fiber is improved, and delamination can be prevented.

  Further, as shown in FIG. 5, by including the resin curing step S213 after the second resin impregnation step S212, a molded product using one layer of SMC20 or a molded product using multiple layers of SMC20 can be manufactured. .. At this time, as described above, by stacking the low shrinkage material 25 in the low shrinkage material stacking step S205, the shrinkage of the first paste 23, the second paste 24, the third paste 27, and the fourth paste 28 is reduced. The warp of the SMC 20 can be suppressed by being suppressed by the material 25. Further, in the low shrinkage material laminating step S205, since the low shrinkage material 25 is laminated on the SMC 20, it is not necessary to add the low shrinkage agent to the thermosetting resin paste laminated in each resin laminating step.

  As described above, the SMC manufacturing method S200 of the present embodiment is a low shrinkage material in which the film-shaped low shrinkage material 25 is laminated on the thermosetting resin paste or the reinforcing fibers dispersed on the paste. It has a laminating step S205. Therefore, the same effects as those of the SMC manufacturing method S100 of the first embodiment described above can be obtained.

  The embodiment of the present invention has been described in detail above with reference to the drawings, but the specific configuration is not limited to this embodiment, and there are design changes and the like within the scope not departing from the gist of the present invention. However, they are included in the present invention.

10 SMC
12 First reinforcing fiber 13 First paste 14 Low shrinkage material 20 SMC
22 First Reinforcing Fiber 23 First Paste 25 Low Shrinkage Material S100 SMC Manufacturing Method S103 First Fiber Dispersion Step S104 Low Shrinkage Material Laminating Step S108 First Resin Impregnation Step S109 Resin Curing Step S200 SMC Manufacturing Method S203 First Fiber Dispersion Step S205 Low shrinkage material laminating step S206 First resin impregnation step S213 Resin curing step

Claims (1)

A first fiber spreading step of spreading the cut first reinforcing fibers on the first paste of thermosetting resin; a first resin impregnating step of impregnating the first paste into the first reinforcing fibers; 1. A method of manufacturing a sheet molding compound, comprising: a resin curing step of heating and curing the first paste impregnated into the reinforcing fiber,
After the first fiber spraying step and before the first resin impregnating step, a low shrinkage layer in which a film-shaped low shrinkage material is laminated on the first paste via the first reinforcing fibers. A method for manufacturing a sheet molding compound, which comprises a material laminating step.

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