JP2009160756A - Manufacturing method for internal-mold coated article, and internal-mold coated article forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an internal-mold coated article having no sink on the surface even if a thermosetting coating layer on the surface is shrunk. <P>SOLUTION: The internal-mold coated-article forming mold includes a back-forming mold, a front-molding mold and a film-forming mold. By using the internal-mold coated-article forming mold, the back-forming mold and the front-forming mold are opened while the back-forming mold holding a molded article, and the back-forming mold and the film-forming mold holding the molded article are closed to form a coating cavity for coating the surface of the molded article with the thermosetting paint between the molded article and the film-forming mold. The thermosetting paint is injected in the coating cavity, and the injected thermosetting paint is pressurized almost at the same time of completion of injection. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  In the present invention, after injecting a thermosetting paint between the surface of a molded product molded in a mold and the mold cavity surface, the thermosetting paint is cured while being compressed in the mold, The present invention relates to an in-mold coated product manufacturing method and an in-mold coated product forming apparatus in which a thermosetting coating is closely integrated with a surface.

  As a conventional in-mold coating method, two cavity molds, an injection cavity mold 101 and a decorative cavity mold 104, are used. A cavity is formed on the surface of the molded product in 104, a decorative coating material made of a liquid thermosetting composition is pressed into the cavity, and a decorative coating 105 is formed on the surface of the molded product. Patent Document 1 discloses a method for injection of a molded product and a decorative molding method by exchanging dies (see FIG. 14).

Japanese Patent No. 3998660

  However, a decorative coating material made of a liquid thermosetting composition is greatly shrunk by curing, and the shrinkage rate is sometimes 5% or more, which is much higher than the shrinkage rate of general molding resins. For this reason, there is a problem that sink marks appear on the surface of the molded product.

  An object of the present invention is to provide an in-mold coated product manufacturing method and an in-mold coated product forming apparatus for preventing the above-described problems from occurring even when the coating material shrinks.

  In order to achieve the above object, the present invention has the following features.

  The method for producing an in-mold coated product of the present invention uses an in-mold coated product forming mold including a back surface forming mold, a surface forming mold, and a coating film forming mold. (1) Back surface forming mold and surface forming The mold is closed and a molding cavity for forming a molded product is formed between the back surface forming mold and the front surface forming mold. (2) The molding cavity is filled with molding resin and cooled and solidified. (3) Open the back surface forming mold and the front surface forming mold in a state where the back surface forming mold holds the molded product, and (4) open the mold facing the back surface forming mold. In order to replace the surface forming mold with the coating film forming mold, the back surface forming mold or the surface forming mold and the coating film forming mold are switched, and (5) the back surface forming mold and the coating film forming mold for holding the molded product. Close the mold and mold the coating cavity for coating the surface of the molded product with thermosetting paint. Formed between the mold (6) a heat-curable coating is injected into the coating cavity, injecting completed almost simultaneously, taking the step of pressurizing the injected thermosetting coating.

  In the above invention, the molded product is composed of a tab portion and a product portion, and the thickness of the coating cavity formed on the surface of the tab portion is formed to be greater than the thickness of the coating cavity formed on the surface of the product portion. It may be.

  An in-mold coated product manufacturing method of the present invention includes an in-mold coated product forming mold, a paint injecting machine for injecting a thermosetting paint, a mold clamping mechanism, a switching mechanism, a mold temperature controller, An in-mold coated product forming mold comprising a back surface forming mold, a surface forming mold, and a coating film forming mold, and the back surface forming mold is a compression block and an outer peripheral plate positioned around the compression block. The coating film forming mold is provided with a paint gate, and the switching mechanism is used to replace the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold. The mold can be switched between the mold and the film-forming mold, and the molded product can be formed by the back-side mold and the surface-forming mold. A thermosetting paint layer can be formed, and the operation of the movable platen of the mold clamping mechanism Te compression block can be moved to the film-forming die side of the outer peripheral plate, a configuration including a temperature adjusting unit for paint implanter is not to cure the thermosetting paint.

  In the above invention, the slide bushing between the compression block and the outer peripheral plate may be positioned on the molding cavity surface where the molded product is formed.

  In the above invention, two or more back surface forming molds may be provided.

  The method for producing an in-mold coated product of the present invention includes a back surface forming die, a surface forming die, and a coating film forming die, and the back surface forming die includes a compression block and an outer peripheral plate positioned around the compression block. In order to replace the mold in the mold where the coating film forming mold has a paint gate and the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold or Using a switching mechanism for switching between the surface forming mold and the coating film forming mold, (1) the back surface forming mold and the surface forming mold are closed, and a molding cavity for forming a molded product is compressed block (2) Filling the molding cavity with a molding resin and cooling and solidifying it to form a molded product, (3) With the compression block holding the molded product Open the back surface forming mold and the front surface forming mold, and (4) In order to replace the mold facing the surface forming mold from the surface forming mold to the coating film forming mold, the back surface forming mold or the surface forming mold and the coating film forming mold are switched by a switching mechanism, and (5) molding Close the mold for forming the back surface and the film forming mold that holds the product, and provide a coating cavity for coating the molded product with the thermosetting paint between the molded product, the film forming mold, and the outer peripheral plate. (6) The thermosetting paint was injected from the paint gate into the coating cavity, and almost simultaneously with the completion of the injection, the compression block was moved toward the coating film mold side with respect to the outer peripheral plate. A step of applying pressure to the thermosetting paint is taken.

  In the above invention, the slide bushing between the compression block and the outer peripheral plate may be positioned on the molding cavity surface where the molded product is formed.

  In the above invention, the method of replacing the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold is fixed to the surface forming mold and the coating film forming mold or the back surface forming mold. Alternatively, it may be caused by rotation of a movable plate of the injection molding machine or a rotary plate attached to the movable plate.

  Moreover, in said invention, it has an at least 2 back surface formation metal mold | die, the process of said (1)-(2) using one back surface formation metal mold | die and a surface formation metal mold, another back surface formation metal mold, You may make it perform the process of said (5)-(6) using a coating-film formation die simultaneously.

  The method for producing an in-mold coated product of the present invention uses an in-mold coated product forming mold including a back surface forming mold, a surface forming mold, and a coating film forming mold. (1) Back surface forming mold and surface forming The mold is closed and a molding cavity for forming a molded product is formed between the back surface forming mold and the front surface forming mold. (2) The molding cavity is filled with molding resin and cooled and solidified. (3) Open the back surface forming mold and the front surface forming mold in a state where the back surface forming mold holds the molded product, and (4) open the mold facing the back surface forming mold. In order to replace the surface forming mold with the coating film forming mold, the back surface forming mold or the surface forming mold and the coating film forming mold are switched, and (5) the back surface forming mold and the coating film forming mold for holding the molded product. Close the mold and mold the coating cavity for coating the surface of the molded product with thermosetting paint. Formed between the mold (6) thermosetting coating in coating cavity is injected, the injection completion almost simultaneously, characterized in that pressurizing the injected thermosetting coating. Therefore, it is possible to obtain an in-mold coated product having no sink on the surface even when the thermosetting coating layer on the surface contracts.

  In the method for producing an in-mold coated product of the present invention, the molded product is composed of a tab portion and a product portion, and the thickness of the coating cavity formed on the surface of the tab portion is formed on the surface of the product portion. Form more than the thickness of the coating cavity. Therefore, the shrinkage amount in the thickness direction of the thermosetting paint layer formed on the surface of the product portion is smaller than the shrinkage amount in the thickness direction of the thermosetting paint layer formed on the surface of the tab portion. The compression of the thermosetting paint layer formed on the surface of the film is not hindered. In addition, since the tab is installed outside the product, the paint injection trace does not remain on the surface of the in-mold coated product by positioning the paint gate at the tab portion.

  In the in-mold coated product forming apparatus of the present invention, the slide bushing between the compression block and the outer peripheral plate is located on the molding cavity surface where the molded product is formed. Thereby, when moving a compression block to the coating-film formation metal mold | die side with respect to an outer peripheral plate, a thermosetting coating does not penetrate | invade in a slide bushing.

  Embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a method for producing an in-mold coated product of the present invention. FIG. 2 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 3 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 4 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 5 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 6 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 7 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 8 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 9 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 10 is a cross-sectional view showing a method for producing an in-mold coated product of the present invention. FIG. 11 is a cross-sectional view showing the method for producing an in-mold coated product of the present invention. FIG. 12 is a schematic view of a paint injection machine used in the method for manufacturing an in-mold coated product and the in-mold coated product forming apparatus of the present invention. FIG. 13 is a cross-sectional view of an in-mold coated product obtained by the method for manufacturing an in-mold coated product of the present invention. FIG. 14 is a cross-sectional view showing a conventional method for producing an in-mold coated product.

  In the figure, 1 is a surface forming mold, 2 is a coating film forming mold, 3 is a back surface forming mold, 4 is a compression block, 5 is an outer peripheral plate, 6 is a mounting plate, 7 is a coil spring, 11 is a sliding bushing, 12 Is a slide bushing, 13 is a molding cavity, 14 is a coating cavity, 21 is a thermosetting paint layer, 22 is a molded product, 23 is a tab part, 24 is a product part, 25 is an in-mold coating product, 41 is a paint injection machine, 42 is a paint injection unit, 43 is a paint tank, 44 is a paint gate, 101 is an injection cavity mold, 102 is a core mold, 103 is a molded product, 104 is a decorative cavity mold, and 105 is a decorative coating.

  First, a method for producing an in-mold coated product of the present invention will be described with an explanation of an in-mold coated product forming mold used in the present invention.

  The in-mold coated product forming mold used in the present invention includes a back surface forming mold 3, a surface forming mold 1, and a coating film forming mold 2. The back surface forming mold 3 is used to form the back surface shape of the molded product 22. The surface forming mold 1 is used for forming the surface shape of the molded product 22. The coating film forming mold 2 is used for forming the thermosetting paint layer 21 on the surface of the molded product 22.

  The back surface forming mold 3 includes a compression block 4, an outer peripheral plate 5 positioned around the compression block 4, a mounting plate 6 to which the compression block 4 is fixed, and a coil spring 7 between the outer peripheral plate 5 and the mounting plate 6. A thing provided with a flexible elastic body can be used. As the coating film forming mold 2, one having a paint gate 44 can be used.

  The back surface forming die 3 and the surface forming die 1 are closed, and a molding cavity 13 for forming a molded product 22 is formed between the back surface forming die 3 and the surface forming die 1 (FIG. 1). (See (a), FIG. 2). A molded product 22 can be obtained by filling the molding cavity 13 with a molding resin and solidifying by cooling (see FIGS. 1B and 3).

  Next, the back surface forming die 3 and the surface forming die 1 are opened in a state where the back surface forming die 3 holds the molded product 22 (see FIG. 1C and FIG. 4). In order to replace the opposing mold from the surface forming mold 1 to the coating film forming mold 2, the back surface forming mold 3 or the surface forming mold 1 and the coating film forming mold 2 are switched (FIG. 1 (d), FIG. 5). A method for switching the back surface forming mold 3 or switching between the front surface forming mold 1 and the coating film forming mold 2 will be described later.

  Next, the back surface forming mold 3 holding the molded product 22 and the coating film forming mold 2 are closed, and the coating cavity 14 for coating the molded product 22 with a thermosetting paint is formed into the molded product 22 and the coating film. It forms between the formation metal mold | dies 2 (refer FIG.1 (e) and FIG. 6).

  A thermosetting paint is injected into the coating cavity 14 from the paint gate 44, and almost simultaneously with the completion of the injection (see FIG. 1 (f), FIG. 7), the injected thermosetting paint is pressurized to the molded product 22. The in-mold coated product 25 can be manufactured by integrally covering the thermosetting paint layer 21 (see FIG. 1G and FIG. 8). Here, “substantially simultaneously” means that the start of pressurization may be before or after completion of injection within a range where there is no problem in molding. In order to pressurize the injected thermosetting paint, the coil spring 7 is contracted by the operation of the movable platen of the injection molding machine in the mold closing direction, and the compression block 4 is placed on the coating plate forming mold 2 side with respect to the outer peripheral plate 5. (See FIG. 1 (g) and FIG. 8). The slide bushing 11 between the compression block 4 and the outer peripheral plate 5 is preferably located on the surface of the molding cavity 13 where the molded product 22 is formed (see FIG. 2). Thereby, when the compression block 4 is moved to the coating film forming mold side with respect to the outer peripheral plate 5, the thermosetting paint does not enter the slide bushing 11.

  After the thermosetting paint layer 21 is integrally coated on the molded product 22, the movable platen of the injection molding machine is moved in the mold opening direction, and the compressed coil spring 7 is stretched to be compressed while maintaining the mold closed state. After the block 4 is moved away from the coating film forming mold 2, the back surface forming mold 3 and the coating film forming mold 2 are opened while the back surface forming mold 3 holds the in-mold coated product 25. (See FIG. 9 and FIG. 10), the in-mold coated product 25 is taken out, the mold facing the back surface forming mold 3 is replaced from the coating film forming mold 2 to the front surface forming mold 1 (see FIG. 11), and the mold is closed. To complete the molding cycle (see FIGS. 1A and 2).

  As a mold clamping mechanism for performing mold opening and mold closing, for example, a toggle type mold clamping mechanism or a direct pressure type mold clamping mechanism of an injection molding machine can be used.

  The coating film forming mold 2 and the surface forming mold 1 have different shapes, and the coating film forming mold 2 has a larger outer shape than the surface forming mold 1 so that a portion that does not contact the molded product 22 can be formed. design. This non-contact portion corresponds to the coating cavity 14.

  In addition, the material of the compression block 4, the outer peripheral plate 5, and the mounting plate 6 constituting the surface forming mold 1, the coating film forming mold 2, and the back surface forming mold 3 may be the same metal or different. Metal may be used.

  The injection port of the molding resin may be installed on the surface forming mold 1 side (see FIGS. 1 to 4 and 11), or may be on the back surface forming mold 3 side.

  As an elastic body between the outer peripheral plate 5 and the mounting plate 6, a metal coil spring 7 or rubber can be used (see FIGS. 2 to 11).

  The paint gate 44, which is the injection position of the thermosetting paint, may be provided in the center of the surface of the coating cavity 14, but since the paint injection trace remains on the surface of the in-coating product, when the appearance is required, What is necessary is just to install in a keyhole, an emblem attachment position, etc., or to install in the tab part 23 so that the molded article 22 may consist of the tab part 23 and the product part 24 (refer FIG. 2). In this case, it is important that the thickness of the coating cavity 14 formed on the surface of the tab portion 23 is equal to or greater than the thickness of the coating cavity 14 formed on the surface of the product portion 24. By doing so, the shrinkage amount in the thickness direction of the thermosetting paint layer 21 formed on the surface of the product portion 24 is more in the thickness direction of the thermosetting paint layer 21 formed on the surface of the tab portion 23. Since it becomes smaller than the shrinkage amount, the compression of the thermosetting paint layer 21 formed on the surface of the product portion 24 is not hindered. Here, at the tab position, the position of the slide bushing 12 becomes the position of the outer periphery of the tab. However, since the slide bushing 12 is sealed by the molded product 22, the thermosetting paint does not enter the slide bushing 12 (FIG. 8).

  Moreover, both the surface forming mold 1 and the coating film forming mold 2 may be mirror molds, both may be embossed molds, or either one may be a mirror surface and the other may be embossed molds. Also good. Further, a boss or the like may be formed on the back surface forming mold 3.

  The mold temperatures of the back surface forming mold 3 and the front surface forming mold 1 are set by a mold temperature controller. The medium of the mold temperature controller may be water or oil. The temperature suitable for normal molding is set according to the material of the molding resin, and the mold temperature of the coating film forming mold 2 is the temperature at which the thermosetting paint cures within a few seconds depending on the material of the thermosetting paint. Should be set.

  Hereinafter, several methods of replacing the mold facing the back surface forming mold 3 from the surface forming mold 1 to the coating film forming mold 2 by the switching mechanism will be exemplified.

  As a method of replacing the mold facing the back surface forming mold 3 from the surface forming mold 1 to the coating film forming mold 2, the movable plate of the injection molding machine to which the back surface forming die 3 is fixed or the rotating plate attached to the movable plate There is a way to rotate. Alternatively, there is a method of rotating a movable plate of an injection molding machine in which the surface forming die 1 and the coating film forming die 2 are fixed or a rotating plate attached to the movable platen. Here, the back surface forming mold 3 may be only one, or may be two or more. If two or more back surface forming dies 3 are used, one back surface forming die 3 and the front surface forming die 1 are closed to form a molding cavity 13 for forming a molded product with the back surface forming die 3. Formed between the front surface mold 1 and filled with a molding resin in the molding cavity 13 and cooled and solidified to form the molded product 22; and coating with another back surface mold holding another molded product The film forming mold 2 is closed and a coating cavity 14 for coating the molded product with the thermosetting paint is formed between the molded product and the coating film forming mold 2, and the coating cavity 14 is heated. The step of injecting the curable coating material and pressurizing the injected thermosetting coating material can be performed simultaneously with the completion of the injection. By doing in this way, since the thermosetting coating layer 21 can be formed on the surface of another molded product during molding of the molded product, the number of shots per unit time can be increased. The shapes of the respective back surface forming molds may be exactly the same, or may be shapes having different members for forming holes in the molded product, for example. Further, a plurality of back surface forming dies may be formed as an integrated object.

  Alternatively, the back surface forming mold 3 is disposed between the front surface forming mold 1 and the coating film forming mold 2, and the back surface forming mold 3 has a shape in which each of the front surface and the back surface can form a cavity, There is also a method in which the mold 3 can be switched by rotating to exchange the front and back surfaces. The shape of each cavity may be the same or different. In order to rotate the back surface forming mold 3, for example, a rotating disk that rotates on a horizontal plane may be used. Also in this method, since the thermosetting coating layer 21 can be formed on the surface of another molded product while molding one molded product, the number of shots per unit time can be increased. In addition, instead of the back surface forming mold 3, the surface forming mold and the coating film forming mold are fixed on the front and back sides and set on a rotating disk, and each mold faces the back surface forming mold. It can also be made switchable.

  Next, the thermosetting paint used in the method for producing an in-mold coated product of the present invention will be described. The thermosetting paint is injected into the coating cavity 14 from the paint injection machine 41 with an accurate amount for one shot at an appropriate pressure.

  Thermosetting paint materials include one-component paints mainly composed of binder components that can be cured by peroxide catalysts such as unsaturated polyester resins, epoxy acrylate oligomers, urethane acrylate oligomers, and epoxy resin / polyamine curing systems. And a two-component paint such as a polyol resin / polyisocyanate curing system in which a main agent / curing agent is mixed immediately before mold injection. Among them, an oligomer containing an acrylate group or an unsaturated polyester resin, or an ethylenically unsaturated monomer copolymerizable with these components and an organic peroxide initiator having a crosslinking efficiency of 8 or more are contained. Liquid paints are excellent in curability, adhesion, appearance, and weather resistance, can shorten the curing time, and can be applied to resin molding materials for which in-mold coating methods cannot be applied due to problems with adhesion, appearance, and weather resistance. It is very good in that it can be applied.

  What is necessary is just to set suitably as a viscosity of a thermosetting coating according to a pattern and thickness within the range of 2000-7000 mPa * s. Particularly in the case of the present invention, the back surface forming mold 3 and the coating film forming mold 2 have almost no gap other than the cavity, and the mold can be fixed with a strong mold clamping pressure. This is advantageous in that the thermosetting paint does not leak from the coating cavity 14 even if the viscosity is low.

  The paint injection machine 41 applies pressure to the upper part of the paint tank 43, and an accurate amount of thermosetting paint for one shot is sent from the paint tank 43 to the paint injection unit 42 having the structure of metering / injection / valve. It has a structure (see FIG. 12).

  As the position setting of the coating material injection unit 42, it may be provided inside the coating film forming mold 2 (see FIGS. 5 to 10). Alternatively, a thermosetting paint injection port provided in the coating film forming mold 2 may be provided on the mating surface with the back surface forming mold 3 so that the paint injection unit 42 and the resin injection unit of the resin injection machine are vertical. Good. In this case, the back surface forming mold 3 holding the molded product 22 and the coating film forming mold 2 are closed, and the coating cavity 14 for coating the molded product 22 with the thermosetting paint is applied to the molded product 22. In the stage formed between the film forming mold 2 and the coating material injection unit 42 moves forward and directly touches the coating film forming mold 2, and the paint gate is provided with the thermosetting paint on the coating film forming mold 2. It is in a mechanism to be injected into the coating cavity 14 through. The nozzle tip of the paint injection unit 42 is adjusted to approximately 30 ° C. by a temperature controller. This prevents the thermosetting paint from solidifying due to the heat of the mold.

  The injection time of the thermosetting paint is about 1 to 10 seconds, and is appropriately set depending on the material of the thermosetting paint, the size of the coating cavity 14, and the like. The injection pressure of the thermosetting paint is suitably set within a range of about 10 to 400 kgf / cm 2, but it is preferable to set the pressure higher in order to prevent burrs and bubbles in the coating film. Particularly in the case of the present invention, the back surface forming mold 3 and the coating film forming mold 2 have almost no gap other than the coating cavity 14 and can be fixed with a strong mold clamping pressure. This is advantageous in that the thermosetting paint does not leak from the coating cavity 14 even if the injection is performed.

  The thickness of the finally formed thermosetting coating layer 21 is preferably 10 to 300 μm. This is because, in the present invention, sink marks do not appear even if the thermosetting paint layer 21 is relatively thick.

  Next, the molding resin used in the method for producing an in-mold coated product of the present invention will be described. The molding resin is not particularly limited, such as a normal thermoplastic injection molding resin or engineering plastic, or a thermosetting molding resin material, but is preferably one that is easy to mold and has good adhesion to the thermosetting paint. Specific examples include acrylonitrile butadiene styrene resin (ABS resin), polyamide resin, polyethylene resin, polyester resin, polypropylene resin, polybutylene terephthalate resin, and polycarbonate resin.

  The molding resin is filled into the molding cavity 13 by a resin injection machine. An injection molding machine can be used as the resin injection machine.

  An in-mold coated product 25 was manufactured using an in-mold coated product forming mold including a back surface forming mold 3 having a cavity on each of the front and back surfaces, a surface forming mold 1 and a coating film forming mold 2. The back surface forming mold 3 includes a compression block 4, an outer peripheral plate 5 positioned around the compression block 4, a mounting plate 6 to which the compression block 4 is fixed, and a coil spring 7 between the outer peripheral plate 5 and the mounting plate 6. used. As the coating film forming die 2, a coating film injection unit 42 including a paint gate 44 was used. Further, the slide bushing between the compression block 4 and the outer peripheral plate 5 is positioned on the molding cavity surface where the molded product 22 is formed.

  Of the two back surface forming molds 3 fixed to the rotating plate attached to the movable plate of the injection molding machine and set at a mold temperature of 105 ° C., one of the back surface forming dies 3 is also set at a mold temperature of 105 ° C. The mold is closed with respect to the surface-forming mold 1 formed to form a molding cavity 13, and then the heat-melted solid color heat-resistant ABS resin is filled in the molding cavity 13 and cooled for 40 seconds to open the back-surface forming mold 3. Thus, a rectangular parallelepiped molded product 22 having a length of 100 mm, a width of 50 mm, and a height of 3 mm was obtained while being held by the back surface forming mold 3. Next, the back surface forming mold 3 holding the molded product 22 is rotated by 180 degrees, and the surface of the back surface forming mold 3 that holds the molded product 22 has a cavity whose outer shape has a length of 100.5 mm and a width of 50. 5 mm, 3.2 mm in height and the mold temperature is switched to face the coating film forming mold 2 set to 105 ° C., the back surface forming mold 3 and the coating film forming mold 2 are closed, A coating cavity 14 was formed between the molded product 22 and the coating film forming mold 2. Next, a thermosetting paint (Praglas 8000 viscosity 3000 mPa · s made by Dainippon Paint Co., Ltd.) is injected into the coating cavity 14, and the movable platen is moved in the mold closing direction almost simultaneously with the completion of the injection. The injected thermosetting paint was pressed and held for 40 seconds to solidify the thermosetting paint. When pressurizing the thermosetting paint, the thermosetting paint did not enter the slide bushing 11 between the compression block 4 and the outer peripheral plate 5. By opening the coating film forming mold 2, an in-mold coated product 25 in which the thermosetting paint layer 21 was integrally coated on the molded product 22 was obtained (see FIG. 13). No sink marks were found on the surface of the obtained in-mold coated product 25.

  The molded product 22 includes a tab portion 23 and a product portion 24, and the thickness of the coating cavity formed on the surface of the tab portion 23 is greater than the thickness of the coating cavity formed on the surface of the product portion 24. In the same manner as in Example 1, the in-mold coated product 25 was obtained by cutting the tab portion 23 with the paint injection mark (see FIG. 13). Compression of the thermosetting paint layer 21 was not inhibited, and no sink marks were found on the surface of the obtained in-mold coated product 25.

It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the in-mold coating goods of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic of the coating material injection machine used for the manufacturing method of the in-mold coating goods of this invention, and the in-mold coating goods formation apparatus. It is sectional drawing of the in-mold coating goods obtained by the manufacturing method of the in-mold coating goods of this invention. It is sectional drawing which shows the manufacturing method of the conventional in-mold coating goods.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface forming die 2 Coating film forming die 3 Back surface forming die 4 Compression block 5 Outer peripheral plate 6 Mounting plate 7 Coil spring 11 Slide bushing 12 Slide bushing 13 Molding cavity 14 Coating cavity 21 Thermosetting paint layer 22 Molded product 23 Tab Part 24 Product part 25 In-mold coated product 41 Paint injecting machine 42 Paint injecting unit 43 Paint tank 44 Paint gate 101 Injection cavity mold 102 Core mold 103 Molded article 104 Decorating cavity mold 105 Decorating coating

Claims (9)

Using an in-mold coated product forming mold comprising a back surface forming mold, a surface forming mold, and a coating film forming mold,
(1) The back surface forming mold and the surface forming mold are closed, and a molding cavity for forming a molded product is formed between the back surface forming mold and the surface forming mold,
(2) Fill a molding cavity with a molding resin and cool and solidify it to form a molded product.
(3) Open the back surface forming mold and the surface forming mold in a state where the back surface forming mold holds the molded product,
(4) In order to replace the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold, the back surface forming mold or the surface forming mold and the coating film forming mold are switched,
(5) The back surface forming mold and the coating film forming mold for holding the molded product are closed, and the coating cavity for coating the surface of the molded product with a thermosetting paint is formed into the molded product and the coating film forming mold. Formed between and
(6) A method for producing an in-mold coated product, which comprises injecting a thermosetting paint into a coating cavity and pressurizing the injected thermosetting paint almost simultaneously with the completion of the injection.   The mold according to claim 1, wherein the molded product includes a tab portion and a product portion, and the thickness of the coating cavity formed on the surface of the tab portion is greater than the thickness of the coating cavity formed on the surface of the product portion. Manufacturing method for painted products. In-mold coated product forming mold, paint injecting machine for injecting thermosetting paint, mold clamping mechanism, switching mechanism, mold temperature controller, and resin injecting machine,
The in-mold coated product forming mold includes a back surface forming mold, a front surface forming mold, and a coating film forming mold,
The back surface forming mold includes a compression block and an outer peripheral plate positioned around the compression block,
The film-forming mold has a paint gate,
The switching mechanism is to switch the back surface forming mold or the surface forming mold and the coating film forming mold in order to replace the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold,
A molded product can be formed by a back surface forming mold and a surface forming mold,
A thermosetting paint layer can be formed on the surface of the molded product by the back surface forming mold and the coating film forming mold.
The compression block can be moved to the coating film forming mold side with respect to the outer peripheral plate by the operation of the movable plate of the mold clamping mechanism,
An in-mold coated product forming apparatus, comprising: a temperature adjusting unit for preventing the thermosetting coating material from being cured by the coating material injection machine.   The in-mold coated product forming apparatus according to claim 3, wherein the slide bushing between the compression block and the outer peripheral plate is located on a molding cavity surface on which a molded product is formed.   The in-mold coated product forming apparatus according to any one of claims 3 to 4, wherein two or more back surface forming molds are provided. A back surface forming mold, a surface forming mold, and a coating film forming mold are provided.
The back surface forming mold includes a compression block and an outer peripheral plate positioned around the compression block,
In-mold coated product forming mold in which the coating film forming mold has a paint gate,
In order to replace the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold, using a back surface forming mold or a switching mechanism for switching between the surface forming mold and the coating film forming mold,
(1) The back surface forming mold and the surface forming mold are closed, and a molding cavity for forming a molded product is formed between the compression block, the outer peripheral plate, and the surface forming mold.
(2) Fill a molding cavity with a molding resin and cool and solidify it to form a molded product.
(3) Open the back surface forming die and the surface forming die while the compression block holds the molded product,
(4) In order to replace the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold, the back surface forming mold or the surface forming mold and the coating film forming mold are switched by a switching mechanism,
(5) The back surface forming mold and the coating film forming mold for holding the molded product are closed, and a coating cavity for coating the molded product with the thermosetting paint is formed on the molded product, the coating film forming mold, and the outer periphery. Formed between the plate and
(6) The thermosetting paint injected by injecting the thermosetting paint from the paint gate into the coating cavity and moving the compression block to the coating film forming mold side with respect to the outer peripheral plate almost simultaneously with the completion of the injection. A method for producing an in-mold coated product, characterized by pressurizing.   The method for manufacturing an in-mold coated product according to claim 6, wherein the slide bushing between the compression block and the outer peripheral plate is located on a molding cavity surface on which the molded product is formed.   The method of replacing the mold facing the back surface forming mold from the surface forming mold to the coating film forming mold is a movable plate of an injection molding machine in which the surface forming mold and the coating film forming mold or the back surface forming mold are fixed. Or the manufacturing method of the in-mold coating goods in any one of Claim 1, 2, 6, 7 which is based on rotation of the turntable which is attached to a movable board.   There are at least two back surface forming molds, and the above steps (1) to (2) using one back surface forming mold and the front surface forming mold, and other back surface forming molds and coating film forming molds are used. The method for producing an in-mold coated product according to any one of claims 1, 2, and 6 to 8, wherein the steps (5) to (6) are simultaneously performed.

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