JP2002355837A - Mold and method for manufacturing molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold surely preventing a positional deviation of a boundary part (boundary line) of a skin material or occurrence of a wrinkle. SOLUTION: A method for manufacturing a molding comprises the steps of supplying a molten state thermoplastic resin to rear sides of first and second adjacent skin materials to each other in a planar direction by using a pair of male and female molds, and laminating the skin materials and the thermoplastic resin. The mold of the male and female molds disposed at the rear side of the skin materials comprises a gate (first gate) for supplying the molten state resin to the rear side of the first skin material, and a gate (second gate) for supplying the molten state resin to the rear side of the second skin material. The mold further comprises a sandwiching element for sandwiching the boundary contained so as to enable the element to be protruded at a position corresponding to the boundary of the first and the second skin materials of the molding surface of the mold disposed at the rear side of the skin material. A sidewall of the element becomes a resin stop wall which can prevent an invasion of the resin from the first and second gates to the boundary when the element protrudes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold useful for producing a multilayer molded article in which a skin material is adhered to a thermoplastic resin base material, and a method for producing the multilayer molded article.

[0002]

2. Description of the Related Art A multilayer molded body in which a skin material is bonded to a surface of a base material formed of a thermoplastic resin is excellent in manufacturing cost, light weight, and shapeability, and is used for automobile interior parts (for example, It is widely used in a wide range of fields, including door trims and instrument panels, and interior and exterior parts of home appliances.

[0003] As the multilayer molded body, a molded body having a plurality of design surfaces formed on the surface of the molded body (hereinafter sometimes referred to as a multi-faced molded body) is known. For example, when a plurality of design surfaces having different patterns, materials, and the like are formed, the surface of the base material can be effectively decorated. As the polyhedral molded body, a molded body in which one skin material having a plurality of design surfaces is bonded to a base material, and a molded body in which a plurality of skin materials are bonded to a base material are known. For example, a molded body on which a plurality of skin materials are bonded is a method in which a molten resin is supplied to the back side of a single skin material, and the skin material and the resin are molded while being bonded (injection molding method, compression molding method). And the like, and a plurality of multilayer molded bodies are manufactured, and these multilayer molded bodies are joined in a plane direction by heat fusion or the like. The polyhedral shaped body is also manufactured by manufacturing a resin base material by an injection molding method, a compression molding method, or the like, and bonding a plurality of skin materials to the surface of the base material. However, in the former method, the strength of the joint between the substrates may be insufficient. In the latter method, the skin material may peel off.

As a method for solving these problems, for example, a pair of male and female dies are used to join two skin materials adjacent to each other in a plane direction, and then these skin materials are turned so that the back surface faces the male mold. A method is known in which the material is inserted into the mold, the molten resin is supplied from the male mold, and the skin material and the resin are molded while being bonded to each other. FIG. 13 is a plan view of a polyhedral molded product (target) to be manufactured by this manufacturing method, and FIG.
FIG. 15 is a cross-sectional view of the polyhedral molded body (target) as viewed from the front, FIG. 15 is a schematic cross-sectional view for explaining the manufacturing method, and FIG. It is a top view. As shown in FIGS. 13 and 14, the target polyhedral molded body is a thermoplastic resin base material 4.
, Two skin materials (a first skin material 1 and a second skin material 2) are adjacently bonded to each other. A boundary (boundary line) 3 between the first skin material 1 and the second skin material 2 forms a clean line without distortion. In the case of manufacturing the polyhedral molded body, as shown in FIG. 15, a first skin material 1 and a second skin material 2 are joined at a boundary portion 3 to a mold composed of a male mold 14 and a female mold 15. Insert the joined skin material. The joined skin material is inserted with the back surface facing the male mold 14 and the front surface is brought into contact with the female mold 15. A first gate 11 for supplying a molten resin to the back surface of the first skin material 1 and a supply of the molten resin to the back surface of the second skin material 2 are formed on the molding surface of the male mold 14. The second gate 12 is formed, and molten resin is supplied from these gates 11 and 12 (see FIG. 15A). Then, the female mold 15 is moved toward the male mold 14 so as to be formed while being pressed (see FIG. 15B). However, in such a method,
The resin supplied from one gate (in this example, the resin 21 supplied from the first gate 11) is replaced by the resin supplied from the other gate (in this example, the resin supplied from the second gate 12). Boundary part (joining part) 3 before 22)
May be reached, and the position of the boundary may be shifted. Therefore, as shown in FIG. 16, the boundary portion 3 between the first skin material 1 and the second skin material 2 meanders, and it is difficult to form a clean line.

Therefore, a method of molding while fixing the boundary 3 has been proposed (Japanese Patent Laid-Open No. 2-117511). FIG. 17 is a schematic sectional view for explaining this method. This example differs from the example in FIG. 15 in that the boundary 3 between the skin materials 1 and 2 is sandwiched by the fixture 40 and the fixture 40 is embedded in the male mold 14 (FIG. 17).
(See (a)). However, as shown in FIG. 17B, even if the boundary portion 3 is fixed, one resin 21
When it reaches the boundary (joint) 3 earlier than the
Of these, the part that is not fixed may be strongly pressed, and the boundary may be greatly displaced. Therefore, similarly to the example of FIG. 16, the boundary 3 may meander.

[0006] In the above example, an example using two skin materials is shown. However, even when one skin material is used, the position of the boundary may be shifted as in the case of using the two skin materials. is there. That is, the first skin material (skin portion) and the second skin material are replaced with the joined skin material in which the two skin materials (the first skin material 1 and the second skin material 2) are joined at the boundary 3. Even if one skin material having a (skin portion) is used, if one resin reaches the boundary portion before the other resin, the position of the boundary portion is shifted by being pulled by the flow of the resin reaching the end portion. There are cases.

[0007] Regardless of whether two skin materials are used or one skin material is used, the area of the first skin material (skin portion) and the area of the second skin material (skin portion) are reduced. If there is a large difference, if the molded body has a complicated uneven shape, or if the molded body is large and the number of gates is large, the timing shift of the arrival of the resin at the boundary part becomes large, and the position of the boundary part becomes large. Deviations and wrinkles are generated near the boundary, and the appearance is easily deteriorated.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a plurality of skin materials adjacent in a plane direction [a plurality of skin materials, a plurality of skin materials, One skin material composed of a skin material (skin portion)] is bonded to a thermoplastic resin base material to produce a molded body (polyhedral molded body). It is an object of the present invention to provide a mold and a method for manufacturing a molded article, which can surely prevent the displacement of a boundary portion (boundary line) and the occurrence of wrinkles.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, a plurality of skin materials [a plurality of skin materials, a plurality of skin materials (skin portions)] have been formed. When one supplies resin to the back side of
In the mold located on the back side of the skin material, a sandwich is embedded at a position corresponding to the boundary of the skin material (skin portion), and not only does the sandwich hold the boundary of the skin material, When the holding body is made movable and protruded from the male mold, the resin heading toward the boundary can be blocked by the side wall of the holding body, and then the holding body is housed in the male mold and the resin is applied to the boundary in the side wall. It has been found that the infiltration of the resin makes it possible to substantially align the timing at which the resin arrives at the boundary portion, and has completed the present invention.

[0010] That is, the mold of the present invention that can achieve the above object is provided on the back side of the first and second skin materials (the skin material having the first and second skin portions) which are adjacent to each other in the plane direction. A mold for supplying a molten thermoplastic resin and bonding a skin material and a thermoplastic resin to produce a multilayer molded body,
And a first gate for supplying a molten thermoplastic resin to the back side of the first skin material (skin portion); and a supply of the molten thermoplastic resin to the back side of the second skin material (skin portion). A pair of male and female molds formed on a mold in which the second gate is located on the back side of the skin material, and a molding surface of either the male mold or the female mold located on the back side of the skin material. First
And, at a position corresponding to the boundary portion of the second skin material, a holding body housing portion for housing a holding body for holding the boundary portion is formed, and in the holding body housing portion, The holding body is housed so as to protrude, and the side wall of the holding body prevents resin from the first and second gates from entering the boundary portion when the holding body protrudes. This has a gist in that it is a resin stopper wall that can be prevented. It is preferable that the mold located on the front side of the skin material has a projection formed along the boundary at a position corresponding to the boundary of the skin material (skin).

[0011] The method for producing a molded article of the present invention, which has achieved the above object, includes a first and second skin materials (first and second skin materials) which are adjacent to each other in a planar direction using a pair of male and female molds. 2) is disposed on the molding surface of one of the male and female molds located on the back side of the skin material, and is melted on the back surface of the first skin material (skin portion). A first gate for supplying the thermoplastic resin and a second gate for supplying the molten thermoplastic resin on the back surface of the second skin material (skin portion); A method for producing a multilayer molded body by supplying a molten thermoplastic resin from a second gate and bonding the skin material (skin portion) and the thermoplastic resin together, comprising a first and a second skin material ( A clamp body in which a boundary portion of the skin portion is clamped from the back side of the skin material is protruded into a mold cavity, and the first and the second members are projected. When the molten thermoplastic resin supplied from the second gate is filled into the mold cavity, the side wall of the sandwiching body prevents the resin from entering the boundary, and thereafter the sandwiching body is removed from the mold. This has a gist in that the resin is allowed to enter the boundary portion by being housed inside. The sandwiched body is brought into contact with the molding surface of the mold located on the front side of the skin material through the skin material before the resin flowing from the gate reaches the embedded position of the sandwiched body. It is desirable to prevent infiltration of the resin into the resin. Prior to clamping the skin material with the sandwich, the skin material may be shaped according to the shape of the molded body. A preferred molding method is press molding. It is desirable that the holding body protruding into the mold cavity be housed in the mold by the pressure for forming the resin.
In the above manufacturing method, a molten thermoplastic resin (foamable resin) containing a foaming agent may be used as the resin supplied from the first and second gates. When using a foamable resin, after filling the mold cavity with the resin,
The mold cavity may be enlarged and the resin foamed.

In this specification, the term "thermoplastic resin" is used to include a thermoplastic elastomer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the illustrated examples and is not limited to the illustrated examples. It is also possible to implement the present invention with modifications, and all of them are included in the technical scope of the present invention. For example, hereinafter, a case where a female mold is used as a mold located on the front side of the skin material and a male mold is used as a mold located on the back side of the skin material will be described as an example. A male mold may be used as the mold located on the back side of the skin material, and a female mold may be used as the mold located on the back side of the skin material.

FIG. 1 is a plan view showing an example of a multilayer molded article (multi-layer multi-face molded article) which can be produced by the present invention.
FIG. 2 is a cross-sectional view of the molded body viewed from the front. This molded body is composed of a first skin material 1 and a second skin material
It is manufactured by supplying a molten (fluid) thermoplastic resin to the back side of the skin material 2 and bonding the skin material and the thermoplastic resin to each other. Although the area of the second skin material 2 is larger than the area of the first skin material 1, the boundary (boundary line) 3 between these skin materials 1 and 2 is obtained.
Forms a clean line without distortion. Hereinafter, the mold of the present invention capable of producing such a molded article and the method for producing the molded article will be described in detail.

3 to 6 are schematic sectional views showing an example of a method of manufacturing the molded body and a mold used in the method. FIG. 7 is a plan view of a molding surface of the male mold 14 in the mold. FIG. 8 is a schematic perspective view of a holding body used in the mold, FIG. 9 is a cross-sectional view taken along line AA ′ of the holding body, and FIG. FIG. 4 is a sectional view taken along line -B ′.

The mold 10a shown in FIGS. 3 to 7 comprises a male mold 14 and a female mold 15 for forming a thermoplastic resin in pairs with each other. On the molding surface of the male mold 14,
First gates (resin supply ports) 11a and 11b for supplying molten resin to the back side of the first skin material 1;
Second gates (resin supply ports) 12a and 12b for supplying the molten resin are formed on the back side of the skin material 2 of FIG. The first gate 11 and the second gate 1
In order to prevent the molten resin flowing from the mold 2 from flowing toward the boundary 3 between the skin material 1 and the skin material 2, it corresponds to the boundary between the first and second skin materials on the molding surface of the male mold 14. A sandwiching body 40a is buried in a position 13 (which may be hereinafter referred to as a planned boundary position or a planned boundary line) that faces (opposed). The holding body 40a is supported by a shaft 48 connected to a cylinder (not shown), and can protrude from the male mold.

More specifically, as shown in FIGS. 8 to 10, the holding body 40a is composed of a pair of holding pieces 41 and 42 symmetrical with respect to the skin materials 1 and 2 to be held. The holding pieces 41 and 42 are for holding the skin materials 1 and 2 from the back side at the boundary portion 3 and holding portions 44 a and 44 b for holding the molten resin and bonding the skin materials 1 and 2 to the resin at the boundary portion 3. In addition to the resin housing portion 43, there are also side walls (resin stopper walls) 45 and 46 for temporarily blocking the molten resin toward the resin housing portion 43. That is, the side walls 45 and 46 are formed so as to face the boundary portion 3, and the first and second side walls 45 and 46 are formed by projecting the holding body 40 a from the male mold. It is possible to prevent the resin from the second gate from entering the resin housing portion 43 (that is, the boundary portion 3).
In the holding body 40a, the holding portions 44a and 44b and the skin materials 1 and 2 are penetrated by the pins 47 to prevent the skin materials 1 and 2 from falling out of the holding portions 44a and 44b. The holding body 40a is detachable from a male type. In addition, the skin materials 1 and 2 can be sandwiched by the sandwiching portions 44 a and 44 b, the skin materials 1 and 2 can be bonded to the resin by the resin housing portion 43, and the molten resin heading toward the resin housing portion 43 by the side walls 45 and 46 is temporarily removed. The shape of the holding body is not particularly limited as long as the holding piece can be blocked. For example, the holding pieces 41 and 42 may be asymmetric. On the other hand, the holding portions 44a and 44b, which are a part of the holding pieces 41 and 42, are desirably substantially symmetrical. For example, except that the other holding portion has no such groove.)

By using the above-described mold 10a, a multilayer multi-faced molded article can be manufactured as described below. That is, as shown in FIG. 3, the back surfaces of the first and second skin materials 1 and 2 which are adjacent to each other in the plane direction are directed to the male mold 14,
After the boundary 3 between the skin materials 1 and 2 is clamped by the clamp body 40a, the clamp body 40a is
The holding body 40a is pushed up by a shaft 48 standing up in the housing portion 16, and the holding body 40a
a is projected into the mold cavity. Also, the mold 10a is widely opened to form a space larger than the space corresponding to the molded body. And the first gates 11a and 11b
Supplies the molten thermoplastic resin to the back side of the skin material 1 from the second gates 12a and 12b.

After the supply of the molten thermoplastic resin, the female mold 15 is moved toward the male mold 14 (ie, mold clamping is started), and the molten thermoplastic resin 21 is placed in the mold cavity while pressing the resin. , 22 are filled. At the stage of filling the molten thermoplastic resin 21, 22, since the sandwiching body 40 a remains protruding from the molding surface, the resin 21, 22 is formed by the side walls 45, 46 of the sandwiching body 40 a.
Can be prevented from entering the resin housing portion 43.

Further, in this example, after the female mold 15 is further moved in the mold clamping direction, the holding body 40a is brought into contact with the molding surface of the female mold 15 via the skin materials 1 and 2 [FIG. Reference], while keeping the abutted (pressed) state, the female mold 15 is further approached, and
0a is housed in the male mold 14 (see FIG. 5). That is, the molten resin 2 is placed in the mold cavity by mold clamping.
When filling the molten resin 21, 22,
Are blocked by the skin materials 1 and 2 from entering between the side walls 45 and 46 and the boundary portion 3.

At the stage where the molten resin substantially fills (fills) the outside of the side walls 45 and 46 (ie, the outside when the side where the boundary portion 3 exists is the inside), the female mold 15 is pinched more than the approaching speed. Increase the reverse speed (descent speed) of the body 40a,
A separation portion is provided between the back surfaces of the skin materials 1 and 2 and the upper surface (molding surface) of the sandwiching body 40a.
3 (and the boundary 3) are caused to penetrate the resins 21 and 22. Thus, the timings at which the resins 21 and 22 reach the boundary 3 can be substantially aligned, and the displacement of the boundary can be prevented.

When the clamping body 40a is accommodated (evacuated), the clearance between the male mold 14 and the female mold 15 becomes substantially equal to the thickness q of the molded body (see FIG. 2), and the base material formed of a thermoplastic resin is used. The process is completed before the height of the portion 4 becomes substantially equal to the base material thickness p (see FIG. 2) (that is, until the mold clamping is completed) (see FIG. 6). After completion of the mold clamping, the resin is cooled and solidified, and the mold 10a is opened (the mold is opened) to obtain a molded body as shown in FIGS. Can be.

When performing the mold clamping, either the male mold 14 or the female mold 15 may be moved, or both may be moved. Further, in the illustrated example, an example in which the molded body is manufactured by press molding in which the resin is pressed and the resin is pressed after the supply of the resin is completed, but the die clamping is not necessarily performed after the supply of the resin is completed, It may be performed while supplying. When performing the mold clamping after the supply of the resin is completed, it is desirable to immediately start the mold clamping after the completion of the supply. Further, in the illustrated example, the example in which the mold is clamped in the vertical direction is described, but the mold may be clamped in a direction other than the vertical direction (for example, the horizontal direction).

Further, the molding method is not limited to press molding.
Injection molding may be used, or press molding and injection molding may be combined. For example, when manufacturing a molded body by injection molding, after holding the clamping body 40a sandwiching the skin materials 1 and 2 in the male mold 14 in the same manner as press molding, the mold clamping is completed, and the clamping body 40a is removed. In a state where the gate 1 is protruded (especially in a state where the holding body 40a is abutted against the female mold 15),
From 1 and 12, the supply of the molten thermoplastic resin is started. Then, the supply of the resin is continued, and the resins 21 and 22 supplied from the gates 11 and 12 are applied to the side walls 45 and 46 of the sandwiching body 40a.
After substantially filling (filling) the outside of the body, the holding body 40a is accommodated (retracted) in the male mold 14, and is separated between the back surfaces of the skin materials 1 and 2 and the upper surface (forming surface) of the holding body 40a. A portion is provided, and the resins 21 and 22 enter the resin housing portion 43 (and the boundary portion 3) through the separation portion. When combining press molding and injection molding, there is a method in which the same operation as in the press molding is performed except that the initial resin supply amount is small, and the insufficient resin is injected and supplied at an appropriate stage. .

The preferred molding method is press molding. In the case of injection molding, the injected molten resin immediately comes into contact with the skin material, and the skin material may be exposed to high temperatures and high pressures, which may damage the skin material. Since the resin is supplied, there is little possibility that the skin material may be damaged by the resin supply pressure.

In the present invention, as described later,
As the resin supplied from the first and second gates, a molten thermoplastic resin (foamable resin) containing a foaming agent can be used. When a foamable resin is used, the obtained molded body may be foamed after being taken out of the mold, but it is desirable to foam the molded body in the mold.

FIG. 11 is a schematic sectional view for explaining the case where the resin is foamed. In this example, the mold 10a is used, and the foamable resin 2 is injected into the mold cavity by the molding (press molding, injection molding, etc.).
After the filling of the molds 1 and 22 is completed (see FIG. 6), the mold cavity is enlarged by moving the male mold 14 or the female mold 15 in a direction opposite to the mold clamping direction, and the filling resin (base resin) is formed. 4
Is foamed (FIG. 11).

When the mold cavity is filled with the foamable resin 21 or 22 in a molten state, the cavity clearance formed by the male mold 14 and the female mold 15 at the time of filling is controlled to prevent the escape of the foaming gas. Then, it is desirable to prevent insufficient foaming during the foaming operation after the filling is completed. That is, the cavity clearance is usually the skin material 1,
It is appropriately set according to the molding conditions such as the type 2 and the resin temperature. When filling with a foaming resin, it is desirable to prevent the escape of the foaming gas by paying attention to reducing the cavity clearance.

Foamable resin 21 and 2 in mold cavity
After completing the filling of 2, the resin surface layer is preferably cooled to form a skin layer before the mold cavity is enlarged. If the skin layer is too thick, a sufficient expansion ratio cannot be obtained. Therefore, it is desirable to control the thickness of the skin layer to such a degree that a sufficient expansion ratio can be obtained. The thickness of the skin layer can be controlled, for example, by adjusting the time for forming the skin layer in consideration of the thickness of the molded product, the mold temperature, and the like.

When expanding the mold cavity, the degree of expansion (expansion allowance) is determined by the thickness of the product to be manufactured (expansion ratio).
Can be determined as appropriate. When expanding and foaming the mold cavity, it is desirable that the holding body 40a be kept housed in the mold.

The foaming method is performed by the mold 10 shown in FIGS.
The invention is not limited to the case where a is used, but can be adopted when other various molds including a mold described later are used.

In the present invention, the skin materials 1 and 2 are applied according to the shape of the molded body (ie, the shape of the female mold 15) before being sandwiched by the sandwiching body 40a and disposed in the mold. It may be shaped (preformed).

The boundary 3 between the skin materials 1 and 2 is
a), as necessary, other methods, for example, a chemical bonding method (adhesive or heat sealing), or a method using a jig (sewing with a thread; needle,
Pin, stapler, etc.). In the illustrated example, it is fixed by a pin 47.

In the present invention, the start of the projection of the holding body is
It is not always necessary to start the supply of the resins 21 and 22, and it may be performed at the latest until the resins 21 and 22 reach the embedded position of the sandwiching body. In particular, the clamping body is
By the time the resins 21 and 22 reach the embedding position of the resin stopper plate, it is desirable to abut the molding surface of the mold located on the front side of the skin material via the skin material.

The holding of the sandwiched body may be completed by the time the filling (filling) of the resin into the mold cavity (the space corresponding to the molded body) is completed. That is, in the case of press molding, it is only necessary to complete the accommodating body in the mold until the mold is completed and the mold cavity is filled with the resin. It is sufficient that the holding of the sandwiched body in the mold is completed before all the resin is injected into and supplied to the mold cavity.

The advance (projection) and the backward movement (accommodation, retreat) of the holding body may be controlled by a cylinder (air cylinder, hydraulic cylinder) or may be controlled by other means. For example, the force of a spring may be used to advance the clamp body, but it is preferable to use the resin forming pressure to move backward the resin stopper plate.

The holding pressure of the holding body may be constant,
It may be changed for pressure control. In the case of controlling the pressure, for example, when filling the molded part outside the sandwiching body side wall with the resin, the holding pressure is increased to enhance the resin stopping effect, and when the filling of the resin into the outer molded part is substantially completed. , The holding pressure may be lowered, and the sandwiched body may be accommodated in the mold by the resin forming pressure.

In the present invention, the skin materials 1 and 2 of the female mold 15 are used.
It is desirable to provide a projection (wood grain arrow) continuous along the boundary at a position corresponding to the boundary 3 (scheduled boundary position). FIG. 12 is a schematic cross-sectional view showing an example of a mold provided with the protruding portion (wood grain arrow) 50. When a molded body is manufactured using such a mold 10b in the same manner as in the case of the mold 10a in FIGS. 3 to 7 described above, the displacement of the boundary 3 can be more highly prevented by the protrusion 50.

The larger the area difference between the skin material 1 and the skin material 2 (the area difference between the skin material 1 and the skin material 2 when the upper surface of the molded body is viewed after the production of the molded body), the larger the position of the boundary 3 According to the present invention, although the slip and wrinkles are likely to occur, the holding member is protruded according to the present invention, and the side wall (resin stopper wall) prevents the resin from entering the boundary portion 3. Generation of wrinkles and wrinkles can be suppressed. Therefore, the larger the area difference between the skin material 1 and the skin material 2, the more advantageously the present invention can be used. The area ratio between the skin material 1 and the skin material 2 is, for example, skin material 1: skin material 2 = 1:
In the case of about 1 to 1:10, especially about 1: 1.5 to 1:10, it is advantageous to use the present invention.

On the other hand, even if the area difference between the skin material 1 and the skin material 2 is small (especially, even if the area is equal), the shape of the molded body becomes large and the number of gates increases.
When the shape of the molded body is complicated, the flow of the resin is biased, and the displacement and wrinkling of the boundary portion 3 are likely to occur. Therefore, the present invention relates to such a molded body (a large molded body, a complex shaped body). It can also be used advantageously when producing molded articles). Examples of the molded article having a large or complex shape include an automobile door trim and an instrument panel.

The number of skin materials used in the present invention is not particularly limited as long as the design surface has a boundary portion.
The two skin materials (first skin material 1, second skin material 2)
Instead, a single skin material having a first skin material (skin portion) and a second skin material (skin portion) may be used. When one skin material is used, the boundary portion of the skin material (skin portion) is bent and sandwiched from behind with a sandwiching body. Note that when two skin materials are used, a boundary portion is always formed.
And the second skin material may be the same or different.

The number of skin materials (skin portions) is not limited to two, but may be three or more. For example, when a third skin material (skin portion) is formed in addition to the first skin material (skin portion) 1 and the second skin material (skin portion) 2, the third skin material (skin portion) is formed.
The holding body may be buried protrudingly at the expected position of the boundary with the skin material (skin portion) and molded in the same manner as above.

The number of gates for supplying the resin to the back side of each skin material (skin portion) may be at least one, and a plurality of gates may be formed according to the area of the skin material (skin portion). The amount and timing of the resin supplied from these gates are appropriately determined according to the size and shape of the molded product.

In the illustrated example, the thermoplastic resin is introduced into the mold through the common resin introduction passage 9, and the passage is branched in the mold so that the thermoplastic resin is introduced from the first gate 11 and the second gate 12. Although the thermoplastic resin is supplied, separate resin introduction passages (a resin introduction passage for the first gate 11 and a resin introduction passage for the second gate 12) may be provided.

Examples of the skin material that can be used in the present invention include fabrics (for example, woven or knitted fabrics such as moquettes and tricots; nonwoven fabrics and the like), synthetic resin sheets or films, and metal foils (metal foils).

As the fibers constituting the nonwoven fabric, natural fibers (cotton, wool, silk, hemp, etc.), synthetic fibers (polyamide fibers such as nylon, polyester fibers) and the like can be used. These fibers can be used alone or in combination of two or more, and may be spun (for example, blended) if necessary. As the non-woven fabric, a non-woven fabric produced by using the fibers according to a conventional method (a needle punch method, a thermal bonding method, a spun bonding method, a melt blowing method, a spun lace method, etc.) can be used.

As the synthetic resin sheet or film, for example, a thermoplastic resin (for example, polypropylene,
A sheet or film of a polyolefin-based thermoplastic resin such as polyethylene) or a sheet or film of a polyolefin-based thermoplastic elastomer can be used. The polyolefin-based thermoplastic resin (or elastomer) has excellent heat-fusibility to a substrate.

The skin material may be laminated with a backing layer (foam layer, reinforcing layer, heat-resistant layer, etc.) as required. As the foamed layer, polyolefin foams (foams such as polypropylene and polyethylene), polyvinyl halide foams (such as polyvinyl chloride foams), polyurethane foams (such as soft or semi-rigid polyurethane foams) can be used. .

Examples of the reinforcing layer include a nonwoven fabric and a sheet or film made of a synthetic resin. As these nonwoven fabrics and synthetic resin sheets or films, those similar to those exemplified for the skin material can be used.

The above-mentioned backing layers can be used alone or in combination. The backing layer is preferably one that can be heat-laminated with the skin material by either thermal fusion of the skin material or thermal fusion of the backing layer.

The thermoplastic resin constituting the base material 4 of the molded article is not particularly limited as long as it can be subjected to compression molding or injection molding. For example, a polyolefin resin (polypropylene, polyethylene, etc.), a styrene resin (polystyrene) Styrene-butadiene block copolymer, acrylonitrile-styrene-butadiene block copolymer), polyamide resin (eg, nylon), halogen-containing resin (eg, polyvinyl chloride), polycarbonate resin, (meth) acrylate A homopolymer or a copolymer (such as an acrylic resin) can be used. The thermoplastic resin may be a thermoplastic elastomer, for example, an olefin-based thermoplastic elastomer [eg, ethylene-propylene copolymer (EPM), ethylene-propylene-diene copolymer (EPDM)] can be used. .

The thermoplastic resins (and thermoplastic elastomers) can be used alone or in combination of two or more. For example, they may be used as a polymer alloy.

Further, the thermoplastic resin (and the thermoplastic elastomer) contains various additional components such as fillers (inorganic fillers such as glass fiber; organic fillers, etc.), pigments, lubricants, antistatic agents, stabilizers and the like. It may be.

The thermoplastic resin (and thermoplastic elastomer) may contain a foaming agent. By foaming the resin with the foaming agent, a molded article formed of the foamed base material 4 can be obtained. As the foaming agent,
Known chemical foaming agents (such as decomposable foaming agents) used for foaming the thermoplastic resin can be used. For example, inorganic foaming agents such as sodium bicarbonate, ammonium bicarbonate, and ammonium carbonate; N, N Nitroso compounds such as'-dinitrosopentamethylenetetramine; azo compounds such as azodicarbonamide and azobisisobutyronitrile; sulfonyl hydrazides such as benzenesulfonylhydrazide, toluenesulfonylhydrazide and diphenylsulfone-3,3'-disulfonylhydrazide Class; p-
Toluenesulfonyl semicarbazide and the like can be mentioned.
Further, if necessary, it is preferable to add salicylic acid, urea, and a foaming aid containing these. The foaming agent can be appropriately selected in consideration of the melting temperature of the thermoplastic resin to be used, the required expansion ratio, and the like. The addition amount can be appropriately set in consideration of the required strength and required density of the molded article, but is generally about 0.1 to 5 parts by mass with respect to 100 parts by mass of the resin. When performing the above-mentioned foaming operation, in addition to the method in which the chemical foaming agent is contained in the thermoplastic resin, a volatile liquid foaming agent, a gas foaming agent, or the like may be directly pressed into the molten resin in the mold. . As the volatile liquid foaming agent and the gaseous foaming agent, carbon dioxide, nitrogen and the like can be used.

[0055]

According to the present invention, in the mold located on the back side of the skin material, a sandwich is buried at a predetermined boundary position of the skin material (skin portion), and the skin material (skin portion) is buried with the sandwich material. In addition to pinching the boundary part, the pinch body is movable and protruded from the male mold, so that the side wall of the pinch body can prevent the resin from entering the boundary part, and the skin material And the occurrence of wrinkles at the boundary portion (boundary line) can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a plan view of a molded article that can be produced according to the present invention.

FIG. 2 is a sectional view of the molded body of FIG. 1 as viewed from the front.

FIG. 3 is a first view of a series of cross-sectional views illustrating an example of the mold of the present invention.

FIG. 4 is a second view of a series of sectional views showing an example of the mold of the present invention.

FIG. 5 is a third view of a series of sectional views showing an example of the mold of the present invention.

FIG. 6 is a fourth view of a series of sectional views showing an example of the mold of the present invention.

FIG. 7 is a view showing a molding surface of a male mold of the molds shown in FIGS.

FIG. 8 is a schematic perspective view of a holding body used in FIGS. 3 to 6;

FIG. 9 is a cross-sectional view taken along the line AA ′ of the holding body of FIG. 8;

FIG. 10 is a cross-sectional view taken along the line BB ′ of the holding body of FIG. 8;

FIG. 11 is a schematic cross-sectional view for explaining an example of the manufacturing method of the present invention.

FIG. 12 is a sectional view showing another example of the mold of the present invention.

FIG. 13 is a plan view of a molded product (target) to be manufactured by a conventional method.

FIG. 14 is a sectional view of the molded body of FIG. 13 as viewed from the front.

FIG. 15 is a sectional view showing an example of a conventional mold.

FIG. 16 is a plan view of a molded body manufactured by a conventional method.

FIG. 17 is a schematic sectional view showing another example of a conventional mold.

[Explanation of symbols]

 1,2 ... Skin material 3 ... Boundary part 10a, 10b ... Mold 11,11a, 11b, 12,12a, 12b ... Gate 13 ... Scheduled boundary position 14 ... Mold located on the back side of the skin material 15 ... Skin of the skin material The mold 16 located on the front side 16... Sandwiching member housing portions 21 and 22. Molten thermoplastic resin 40 a. Sandwiching members 45 and 46. Sidewalls (resin stopper walls) 50.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F202 AA03 AA13 AD08 AD16 AD20 AD35 AG03 AG20 AH26 CA09 CA11 CB01 CB12 CB20 CK17 CK23 CK52 CQ01 CQ05

Claims (8)

[Claims] A first and a second adjacent to each other in a plane direction.
A mold for supplying a molten thermoplastic resin to the back side of the skin material and bonding the skin material and the thermoplastic resin to produce a multilayer molded body, and a molten mold on the back side of the first skin material. A first gate for supplying a thermoplastic resin, and a second gate for supplying a molten thermoplastic resin to the back side of the second skin material.
The gate and the pair of male and female molds formed in the mold located on the back side of the skin material, the male or female mold located on the back side of the skin material out of the molding surface of one of the molds At a position corresponding to the boundary between the first and second skin materials, a holding body accommodating section for accommodating a holding body for clamping the boundary is formed. The holding body is housed so as to protrude therefrom, and the side wall of the holding body is formed so that the resin from the first and second gates enters the boundary portion when the holding body protrudes. A mold that serves as a resin stopper wall that can prevent the occurrence of a mold. 2. The mold according to claim 1, wherein the mold located on the front side of the skin material has a projection continuously formed along the boundary at a position corresponding to the boundary of the skin material. . 3. A pair of male and female molds, and first and second skin materials adjacent to each other in a plane direction are disposed, and either one of a male mold and a female mold located on the back side of the skin material. A first gate for supplying the molten thermoplastic resin to the back surface of the first skin material, and a second gate for supplying the molten thermoplastic resin to the back surface of the second skin material, on the molding surface of the mold. Forming a multilayer molded body by supplying a molten thermoplastic resin from the first and second gates and laminating the skin material and the thermoplastic resin. And a sandwich body in which a boundary portion of the second skin material is sandwiched from the back side of the skin material,
When the molten thermoplastic resin supplied from the first and second gates is protruded into the mold cavity and is filled into the mold cavity, the side wall of the clamping body causes the resin to reach the boundary. A method of manufacturing a molded body in which infiltration is prevented, and then the sandwiched body is accommodated in a mold so that resin infiltrates a boundary portion. 4. The sandwiched body is brought into contact with the molding surface of the mold located on the front side of the skin material through the skin material before the resin flowing from the gate reaches the embedded position of the sandwich material. The method according to claim 3, wherein: 5. Prior to clamping the skin material with the clamping body,
The manufacturing method according to claim 3, wherein the skin material is shaped according to the shape of the molded body. 6. The mold cavity is filled with resin by pressing the molten thermoplastic resin supplied from the first and second gates with a female mold and a male mold. The manufacturing method as described. 7. The manufacturing method according to claim 3, wherein the holding body protruding into the mold cavity is housed in the mold by a pressure for forming the resin. 8. A mold thermoplastic resin containing a foaming agent is supplied as a resin supplied from the first and second gates, and after the filling of the mold cavity with the resin is completed, the mold cavity is enlarged. The method according to any one of claims 3 to 7, wherein the resin is foamed.