JP2013086342A - Method of manufacturing film insert molded product and molding die of film insert molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a film insert molded product suppressing the rolling of a film end into the molded product, and avoiding the generation of a weld line on a molded product surface observed from a user, and to provide a molding die of the film insert molded product.SOLUTION: The method includes a step of setting a film 100 with the material quality and the color tone of metal, grain and the like printed on a molding surface of a stationary die 2, a step of moving a movable die 3 relative to the stationary die with the film set to perform mold closing, a step of pressing an end 100a of the film on a molten resin flow-in side by a film pressing means 10 with a flow-in port through which the molten resin flows in formed at an upper surface, and a step of injecting the molten resin through a gate while pressing the end 100a of the film on the molten resin flow-in side by the film pressing means 10 to perform molding.

Description

  The present invention relates to a method for producing a film insert molded article and a mold for forming a film insert molded article, and in particular, a method for producing a film insert molded article for injection molding a resin molded article having at least a part of the surface covered with a film. And a film insert molding product.

Conventionally, as a method of imparting a material feeling or color tone of metal, wood, etc. to a resin molded product, a method of applying treatment such as painting or plating, or a method of inserting a film giving a material feeling of metal, wood, etc. to a resin It has been known.
In particular, the film insert molding method in which a film printed with a material or color tone such as metal or wood grain is inserted into a resin has advantages in terms of manufacturing cost and durability compared to processing methods such as painting and plating. For example, they are used in panels of household electrical appliances, interior and exterior parts of automobiles, and the like.

The film insert molding method will be described with reference to FIG. 7 and an example described in Patent Document 1 based on this figure.
First, the film 100 performs printing on the back surface of the base material 101 to form a printing ink layer 102. As the base material 101 of the film 100, a PET film is mainly used, but a PC (polycarbonate) film or the like may be used.

  Next, the binder layer 103 is formed by printing a binder on the printing ink layer 102. The binder layer 103 is an adhesive for the molding resin (molded product) 110 and melts by the heat of the molten resin during molding to become an adhesive, and bonds the printing ink surface and the molding resin (molded product) surface.

  In order to insert-mold the film 100 thus formed, first, the film 100 on which a material such as metal or wood grain and color tone are printed is cut into a predetermined dimension and formed into a predetermined shape. Specifically, after being cut into a predetermined size, it is heated and pressed to form into a predetermined shape.

Thereafter, the film 100 is set on the fixed mold 120 of the injection mold, the movable mold 121 is moved, and after the mold is clamped, film insert molding is performed. That is, molten resin is injected into the cavity C between the fixed mold 120 and the movable mold 121, and the ink layer 102 (film 100) is bonded to the molding resin 110 by the binder layer 103.
Then, after waiting for the molding resin 110 to cool, the product is completed by removing it from the mold.

  By film insert molding as described above, the film 100 can be integrated with the molding resin 110, and the material and color tone of metal, wood grain, etc. printed on the film 100 can be given to the molded product. .

JP 2008-168613 A

By the way, the film insert molding is considered to be applied to a large molded product such as an automobile front bumper. Specifically, a case where the present invention is applied to a front bumper of an automobile will be described with reference to FIG.
As shown in FIG. 8A, a front grill 131 is formed at the upper part of the front bumper 130 of the vehicle, and a radiator grill 132 is provided below the front grill 131. In addition, a circular flat surface portion is formed as an attachment surface 130a of the emblem 133 at the upper central portion of the front bumper 130 (the upper central portion of the front grill 131).

A molding part 130b is formed in the vehicle width direction in contact with the lower end part of the mounting surface 130a of the emblem 133.
Except for the front grill 131 and the radiator grill 132, the front bumper 130, the mounting surface 130a and the molding part 130b of the emblem 133 are integrally formed. Here, in particular, a film printed with a metal color such as silver is inserted into the molding part 130b. Note that G in FIG. 8A indicates a gate position in the mold where the molten resin is injected.

Next, based on FIG.8 (b), the bad effect which arises when inserting a film in the said molding part 130b is demonstrated.
First, the film 100 is set on the fixed mold 134 of the injection mold, the movable mold 135 is moved, and after mold clamping, the molten resin is injected into the cavity C between the fixed mold 134 and the movable mold 135.
At this time, since the gate position G is located above the molding part 130b, the molten resin flows downward from above as indicated by an arrow F in the figure.

For this reason, the molten resin flows between the end portion 100a of the film 100 and the fixed mold 134, and the adverse effect that the end portion 100a is lifted (peeled from the molding surface of the fixed mold 134) occurs.
Due to the lifting of the film 100 (peeling from the molding surface of the fixed mold 134), the end of the film 100 is caught in the resin molded product, and there is a problem that a molded product having a good appearance cannot be obtained.

In order to prevent this problem, it is considered that a tunnel gate TG is formed in the movable mold 135 and a molten resin is injected from the center of the back surface of the film 100 as shown in FIG. 9B. It is done.
According to this method, since the film 100 is pressed from the back surface side of the film 100 to the molding surface side of the fixed mold 135 by the injected molten resin, the lifting of the end portion 100a of the film 100 is suppressed. A molded product can be obtained.
In FIG. 9A, TG represents a gate position (tunnel gate position) where molten resin is injected.

However, as shown by arrows in FIGS. 9A and 9B, most of the molten resin injected from the tunnel gate TG disposed at the center of the back surface of the film 100 is made of gold as shown by the arrow F in the figure. Move toward the top of the mold.
Then, as shown in FIG. 9A, for example, the molten resin injected at a position above the emblem mounting surface 131a visible to the user merges, and a weld line WL appears at the junction. When the weld line WL appears on the surface of the product, the product looks bad and the design value is impaired.
Incidentally, in the case shown in FIG. 8, the weld line WL appears in the molding portion 130 b, but is covered and hidden by the film 100. Therefore, the weld line WL does not appear in the portion visible to the user, and the design value is not impaired.

  The present invention has been made in order to solve the above-described problems, and suppresses the entanglement of the end of the film into the molded product and prevents the weld line from being generated on the surface of the molded product visible to the user. It aims at providing the manufacturing method of a film insert molded article, and the shaping | molding die of a film insert molded article.

  The method for producing a film insert molded product according to the present invention made to solve the above technical problem includes a step of setting a film on which a material or color tone of metal, wood grain, etc. is printed, on the molding surface of a fixed mold, The step of moving and clamping the movable mold with respect to the fixed mold on which the film is set, and after the mold clamping, the molten resin flows into the upper surface of the end of the film on the molten resin inflow side. A step of pressing with a film pressing means in which an inflow port is formed, and a step of injecting and molding the molten resin from the gate while pressing the end of the molten resin inflow side of the film with the film pressing means. It is characterized by.

  In this way, since the molten resin is injected from the gate and molded while holding the end of the film on the molten resin inflow side with the film pressing means, the film end is prevented from getting caught in the resin molded product It is possible to obtain a molded product having a good appearance.

Here, in the injection and molding process of the molten resin, it is preferable that a weld line of the injected molten resin is formed in an insert portion of the film.
Thus, by forming the weld line in the insert portion of the film, the weld line can be covered with the film, and a molded product having a good appearance can be obtained.

  In addition, in the step of injecting the molten resin from the gate while molding the molten resin inflow end of the film by the film pressing means, and after the molten resin has flowed into the cavity, the film pressing means It is desirable to inject and mold the molten resin from the gate in a state where the pressing state of the end of the film is released.

  In this way, after a predetermined amount of molten resin has flowed into the cavity, the inflow amount of the molten resin into the cavity can be increased by releasing the pressing state of the film end by the film pressing means. Can be injected and molded.

  A mold for a film insert molded article according to the present invention made to solve the above technical problem is a mold for a film insert molded article, and the mold includes a fixed mold and a movable mold, The movable mold is provided with a film pressing means for pressing the end of the film set on the fixed mold on the molten resin inflow side in the clamped state.

  In this way, since the film pressing means is provided, if this mold is used, the molten resin can be injected and molded from the gate while pressing the end of the molten resin inflow side of the film. Involvement of the end of the film into the resin molded product due to lifting is suppressed, and a molded product with good appearance can be obtained.

  Here, the film pressing means includes a first slide core that presses an end of the film, an inlet formed by an upper surface of the first slide core into which molten resin flows, and the first slide core. It is desirable to include a moving means that moves the film toward the end of the film and presses the end of the film.

  According to the present invention, a method for manufacturing a film insert molded product and a film insert molded product in which the end of the film is prevented from being caught inside the molded product and a weld line is not generated on the surface of the molded product visible to the user. A product mold can be obtained.

FIG. 1 is a diagram illustrating an embodiment according to the present invention, and is a front view of a front bumper showing a case where a gate is disposed at an upper position of a mold (front bumper). FIG. 2 is a view showing a cross section of a mold for forming the CC cross section shown in FIG. 3 is a cross-sectional view taken along the line DD shown in FIG. 4 is a front view of the first slide core shown in FIG. FIG. 5 is a view corresponding to FIG. 2, and is a cross-sectional view of the mold showing a state in which the molten resin inflow port is opened after a predetermined time has elapsed after the start of injection of the molten resin. FIG. 6 is a cross-sectional view taken along the line EE shown in FIG. FIG. 7 is a diagram for explaining a conventional method for producing a film insert molded article. FIG. 8 is a diagram illustrating a case where the gate is disposed at a position above the mold (front bumper), where (a) is a front view illustrating a front bumper that is a molded product, and (b) is It is a figure which shows the cross section of the metal mold | die which shape | molds the AA cross-section part shown to (a). FIG. 9 is a diagram showing a case where the gate is arranged at the center of the back surface of the film, wherein (a) is a front view showing a front bumper which is a molded product, and (b) is shown in (a). It is a figure which shows the cross section of the metal mold | die which shape | molds BB cross-section part.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. Members that are the same as or equivalent to those shown in FIGS. 7 to 9 are given the same reference numerals, and detailed descriptions thereof are omitted.

  In the present invention, the gate position G is arranged at a position other than the molding portion 130b, and a weld line WL is formed at the molding portion 130b. The film 100 is lifted by the flow of molten resin (from the fixed molding surface). In order to prevent the film from being peeled off, a film pressing means 10 (first slide core 11) for pressing the end portion 100a of the film is provided.

First, a mold for a film insert molded product will be described.
The mold 1 includes a fixed mold 2 and a movable mold 3 that is controlled to move by a movable mold moving means (not shown), as in the conventional mold. Then, the movable mold 3 is configured to move from the mold open state to the mold clamping state shown in FIG.

Further, the movable mold 3 is provided with a film pressing means 10 that presses the end portion 100a on the molten resin inflow side of the film 100 set in the fixed mold 2 in the mold clamping state.
The film holding means 10 includes a first slide core 11 that holds the end 100a of the film 100 on the molten resin inflow side, and a V-shape into which the molten resin formed on the upper surface 11a of the first slide core 11 flows. The inlet 11a which consists of a groove | channel is provided. As shown in FIG. 4, the first slide core 11 is formed in the vehicle width direction along the upper edge portion of the molding part 130b with the same length as the molding part 130b.
The film pressing means 10 includes a second slide core 12 that moves the first slide core 11 in the direction of the end 100a of the film 100, and a rod 13 that has one end attached to the second slide core 12. And a piston cylinder 14 for moving the rod 13 in the horizontal direction.

The first slide core 11 is slidably accommodated in a through hole 3 b formed in the movable mold 3. Further, the lower surface 11c of the first slide core 11 is formed on an inclined surface, and is slidable on the inclined surface formed on the upper surface 12a of the second slide core 12.
That is, as shown in FIG. 2, when the piston cylinder 14 advances the rod 13 to the fixed mold 2 side, the lower surface 11c of the first slide core 11 slides on the upper surface 12a of the second slide core 12. . As a result, the first slide core 11 slides upward in the through-hole 3b, and the upper surface 11a of the first slide core 11 protrudes toward the fixed mold side, thereby pressing the end portion 100a of the film 100. Has been.

  Further, as shown in FIG. 5, contrary to the above operation, when the piston cylinder 14 retracts the rod 13, the lower surface 11 c of the first slide core 11 slides on the upper surface 12 a of the second slide core 12. However, the first slide core 11 slides downward in the through hole 3b, and the projecting first slide core 11 is drawn into the through hole 3b.

Next, the inlet 11a into which the molten resin formed on the upper surface 11a of the first slide core 11 flows will be described.
As shown in FIGS. 2 and 3, a plurality of V-shaped grooves are provided on the upper surface 11 a of the first slide core 11 along the direction in which the molten resin flows.
Therefore, when the upper surface 11a of the first slide core 11 protrudes toward the fixed mold side and presses the end 100a on the molten resin inflow side of the film 100, the upper surface 11a of the first slide core 11 and the above-mentioned A V-shaped inlet 11b through which the molten resin flows is formed between the lower surface of the film 100, and the molten resin flows downward (on the back side of the film 100) through the inlet 11b. ing.
That is, the molten resin flows downward while pressing the end portion 100a of the film 100 on the upper surface 11a of the first slide core 11.

  In addition, the film 100 is the same as the conventional film, but is not limited to this, and may be made of other materials. Further, as described above, the base material 101, the printing ink layer 102, and the binder layer 103 do not have to have a three-layer structure. For example, a two-layer structure or a four-layer structure or more may be used.

Next, a method for producing a film insert molded product will be described.
First, the film 100 is set on the molding surface 2a of the fixed mold 2 when the mold is opened. Note that a cavity C is formed between the molding surfaces 2 a and 3 b of the fixed mold 2 and the movable mold 3 in the clamped state.
After clamping the fixed mold 2 and the movable mold 3, as shown in FIG. 2, the piston cylinder 14 advances the rod 13 toward the fixed mold 2, thereby lowering the lower surface of the first slide core 11 ( (Inclined surface) 11 c slides on the upper surface (inclined surface) 12 a of the second slide core 12.
As a result, the first slide core 11 slides upward in the through hole 3b, the upper surface 11a of the first slide core 11 protrudes toward the fixed mold 2, and the molten resin end portion 100a of the film 100 is obtained. Press down.

At this time, since the V-shaped inflow port 11a is formed in the first slide core 11, the upstream side and the downstream side communicate with each other through the inflow port 11a across the first slide core 11. ing.
In this state, when molten resin is injected from the gate position G shown in FIG. 1 toward the cavity C in which the film 100 is disposed, the molten resin passes through the inflow port 11a and passes through the first slide core 11. Flows from the upstream side to the downstream side. At this time, the end portion 100 a of the film 100 is fixed by the first slide core 11.
Therefore, even when the gate position G is located above the molding part 131 b and the molten resin flows downward from above, the end part 100 a of the film 100 is fixed by the first slide core 11. Therefore, the end 100a of the film 100 can be prevented from lifting (peeling from the molding surface).

  Then, after a predetermined amount of molten resin is filled in the cavity C (after the molten resin has started to be injected into the cavity C, a predetermined time has elapsed), as shown in FIGS. Moves the rod 13 in the opposite direction to the fixed mold 2 side (retracts), thereby moving the upper surface 11a of the first slide core 11 to the movable mold 3 side, and the pressing state of the end portion 100a of the film 100 is changed. Open.

  By moving the first slide core 11 to the movable mold 3 in this way, a gap is formed between the upper surface 11a of the first slide core 11 and the back surface of the film 100 as shown in FIG. 11a expands. And by the expansion of the inflow port 11a, the amount of molten resin flowing into the cavity can be increased, and injection and molding can be performed quickly.

  The first slide core 11 may be retracted at a timing after the cavity C is filled with a predetermined amount of molten resin and filled to such an extent that the end portion 100a of the film 100 does not float up. Although it takes an injection time, the end portion 100a of the film 100 may be pressed on the upper surface of the first slide core 11 until the filling of the molten resin in the cavity C is completed.

By passing through the above process, the molded product in which the film 100 was inserted is resin-molded.
In the film insert molded product manufacturing method and the film insert molded product mold, since the film pressing means (slide core) for pressing the end of the film is provided, the lifting of the end of the film can be suppressed. .
As a result, entrainment of the film into the molded product of the film can be suppressed, and a molded product having a good appearance can be obtained. Further, by forming the weld line WL so as to occur in the portion where the film is inserted, a molded product having a good appearance can be obtained.

In addition, in the said embodiment, although the case where the gate position was arrange | positioned above the said molding part was shown, this invention is not limited to this, A weld line respond | corresponds to the back surface of a film. It suffices if the gate is arranged so as to be formed at the position.
Further, in the above embodiment, the description has been given by taking the molding part formed on the front bumper of the vehicle as an example, but the present invention is not limited to this, and not only the vehicle exterior product and interior product, For example, the present invention can also be applied to household appliance cabinets, operation panels, and the like.

DESCRIPTION OF SYMBOLS 1 Mold 2 Fixed mold 2a Molding surface 3 Moving mold 3a Molding surface 3b Through-hole 10 Film pressing means 11 First slide core 11a First slide core upper surface 11b Inlet port 11c First slide core lower surface 12 Second Slide core 12a Upper surface 13 of second slide core 13 Rod 14 Piston cylinder 100 Film 100a End F of molten resin inflow side of film F Flow of molten resin G Gate position WL Weld line

Claims (5)

A process of setting a film on which a material such as metal, wood grain, or color tone is printed, on a fixed molding surface;
Moving the movable mold with respect to the fixed mold on which the film is set, and clamping the mold;
After the mold clamping, pressing the end of the film on the molten resin inflow side with a film pressing means formed with an inflow port through which the molten resin flows on the upper surface;
The step of injecting and molding the molten resin from the gate while holding the end of the film on the molten resin inflow side by the film pressing means,
A method for producing a film insert molded article, comprising: In the injection and molding process of the molten resin,
2. The method of manufacturing a film insert molded product according to claim 1, wherein a weld line of the injected molten resin is formed in an insert portion of the film. In the step of injecting and molding the molten resin from the gate while pressing the end of the film on the molten resin inflow side by the film pressing means,
The molten resin is injected from the gate and molded after the molten resin has flowed into the cavity, with the film holding means released from the holding state of the end of the film. 2. A method for producing a film insert molded article according to 2. A mold for a film insert molding product,
The mold includes a fixed mold and a movable mold,
A mold for film insert molding, wherein the movable mold is provided with a film pressing means for pressing an end of the film set on the fixed mold on the molten resin inflow side in a clamped state. The film pressing means is
A first slide core that holds the end of the film;
An inflow port through which molten resin formed on the upper surface of the first slide core flows,
Moving means for advancing the first slide core toward the end of the film and pressing the end of the film;
The mold of the film insert molded article according to claim 4, comprising:

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