JP2991321B2 - Plastic molded article having a foam with skin on the surface and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic molded article having a foam with a skin on the surface of a core and a method for producing the same. The phrase "front surface of the core" refers to one surface of the core on the front surface side of the plastic molded product, while the phrase "back surface of the core" refers to one surface of the core on the rear surface side of the plastic molded product.

[0002]

2. Description of the Related Art As shown in FIG. 8, a plastic molded product such as an instrument panel of an automobile has a foam body 67 with a skin provided in a concave portion 63 provided in a part of a core 61 as shown in FIG. With foam on the skin),
Alternatively, as shown in FIG. 9, a side wall 72 is erected around a core 71 and a foamed body 77 is provided in a concave portion 73 surrounded by the side wall 72 (a foamed body provided on the entire surface). )It has been known. Numerals 64 and 74 are skins, and 65 and 75 are foams.

However, in the above-mentioned plastic molded article, there is a problem in that the core is required to have the side walls 62 and 72 of the concave portion, so that the design is restricted. Furthermore, in the case where the foamed body 77 with the skin is provided on the entire surface as in the latter, when the plastic molded article is attached to the mating article, the side wall 72 of the core is interposed between the mating article and the foamed body. Therefore, there is also a problem that the aesthetic feeling is impaired by the side wall 72.

As a method of manufacturing the plastic molded product, as shown in FIG. 10, a skin 84 whose edge is bent substantially in an L-shape to the back side is disposed on a mold surface of a lower mold 93, while the skin is formed by A core 8 having a recess 83 of a size that fits therein
1 is arranged on the mold surface of the upper mold 91, and the skin 84 and the core 8 are arranged.
There is a method of foaming the foaming raw material P injected in one space. In the manufacturing method, the folded edge 85 of the skin is pressed against the inner surface of the side wall 82 of the concave portion of the core by the foaming pressure of the foaming raw material P to seal the folded edge 85 of the skin. .

However, in the above-mentioned method, since the sealing portion is a side portion of the foam, the thickness of the foam is made sufficiently large to improve the sealing performance, and the bent edge portion 85 of the skin and the core are not formed. It is necessary to increase the contact area between the recess and the inner surface of the side wall 82. Therefore, there is a problem that the thickness of the foam portion cannot be reduced. Furthermore, since it is necessary to make the side wall 82 of the concave portion of the core sufficiently high from the viewpoint of the sealing property,
This also has a problem that the design is restricted.

Further, since the edge of the skin is an open end, when the upper and lower molds are closed, the edge of the edge of the skin interferes with the side wall of the concave portion of the core and becomes wrinkled. Even when they do not interfere with each other, they tend to hang inward due to their own weight, and tend to cause defects during foam molding. Further, there is also a problem that a foaming gas or the like as a foaming raw material is trapped between the skin and the concave portion of the core, and a problem such as void (air pool) is easily generated in the foam.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the foregoing points, and has few design restrictions such as a reduction in the thickness of a foamed portion. A plastic molded article having an excellent foam with a skin, and a method of manufacturing the molded article without defects such as voids, the edge of the skin does not interfere with the core when the mold is closed, and does not wrinkle. What you want to do.

[0008]

According to a first aspect of the present invention, there is provided a plastic molded product having a foam with a skin on the surface of a core, wherein the core is formed by penetrating the front and back surfaces at an edge of a mounting portion of the foam with a skin. The foam with a skin has a skin through-hole or a notch having an edge portion having a skin through-hole or a notch penetrating the front and back surfaces, and is bent to the rear surface side in a substantially U-shape in cross section. Are aligned with the core through-hole and the edge surface is in contact with the surface of the core; the skin fills the space between the skin and the core and adheres to the skin and the core; And a foam as a locking portion that fits into the core through hole through the notch.

In a second aspect of the present invention, a skin is arranged on a lower mold surface and a core is arranged on an upper mold surface, and a foaming material injected between the skin and the core is foamed to be integrated with the skin and the core. In the method for producing a plastic molded article having a foam with a skin on the surface by forming a foam on the surface, the skin has an edge having a skin through hole or a notch penetrating the front and back surfaces, the cross section of which is substantially U-shaped. The core is provided with a core through-hole penetrating the front and back surfaces at the edge of the foam-attached portion with the skin, and the core is provided with a core through hole. Aligning the position with the through-hole and disposing the skin on the lower mold surface such that the bent edge surface of the skin abuts against the surface of the core, and disposing the core on the upper mold surface, Foam between the skin and core The is characterized in that foaming agents.

[0010]

The plastic molded article having the foam with skin according to the present invention does not need to provide a recess in the core in which the foam with skin fits, so that the degree of freedom in design is increased. Further, when the plastic molded article is attached to the counterpart article, since the side wall of the concave portion does not exist, the foamed body with the skin and the counterpart article can be brought into close contact with each other, and the aesthetic feeling is improved. In addition, the foam between the skin and the core adheres to the back surface of the skin and the surface of the core, and a part of the foam serves as a locking portion and fits into the through holes in the core and the edge of the skin, so that the skin is attached. There is no danger of foam coming off and rising.

On the other hand, in the manufacturing method, since the edge of the skin is bent in a substantially U-shape, the shape retention of the edge of the skin is higher than that in the L-shape. When closing the mold and the lower mold, the edge of the epidermis does not hang down under its own weight. Furthermore, since there is no side wall of the concave portion in the portion of the core where the edge of the skin is arranged, there is no risk of interference between the core and the edge of the skin when the mold is closed.
Wrinkles and the like do not occur on the edge of the epidermis.

[0012] The edge of the skin is pressed against the inner surface of the core by the foaming pressure of the foaming material injected between the skin and the core, and the sealing is performed on the back side of the molded product. Therefore, unlike the conventional case, the side surface of the foam does not serve as a sealing portion, so that even if the thickness of the foam with a skin is reduced, the sealing property does not decrease.
The foaming gas generated from the foaming material and the air trapped between the skin and the core when the mold is closed are released to the outside through the through-holes formed in the edge of the skin and the core. And the like are prevented from occurring.

Further, after the foaming raw material is filled between the skin and the core by foaming, it enters into the through-holes of the skin and the core. The foaming material adheres to the skin and the core by its self-adhesiveness and cures to form a foam with a skin, and the foaming material that has entered the through-hole forms a locking portion of the foam. As a result, the foam with skin is securely fixed to the core.

[0014] When a concave portion or a groove for releasing foaming gas is provided in the upper mold surface portion where the core through hole is located, the foaming gas and the like can escape more easily, and the generation of voids and the like is reduced. It can be prevented efficiently.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a plastic molded product having on its surface a foam with a skin according to one embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of a main part thereof, and FIG. FIG. 4 is a cross-sectional view of the embodiment of the present invention when the skin and the core are arranged, FIG. 5 is a cross-sectional view of a molding die after injection of the foaming material during the production, and FIG. FIG. 7 is a partial enlarged cross-sectional view of the molding die after foaming is completed.

A plastic molded product 10 having a foam with a skin on its surface shown in FIGS. 1 and 2 is used for an instrument panel of an automobile, and a foam 21 with a skin is provided on the entire surface of a core 11. I have. In the following description, an instrument panel will be described as an example. However, the molded article and the manufacturing method of the present invention are not limited to the instrument panel, and are applied to various molded articles depending on the application. In addition, the present invention is not limited to the one in which the foam with the skin is provided on the entire surface of the core, but is also applicable to the one in which the foam with the skin is partially provided.

The core 11 is made of a hard plastic such as an ABS resin or a plastic having a high shape retention such as a fiber reinforced plastic. The core 11 is an edge portion of a mounting portion of the foam 21 with a skin. Core through-holes 12 penetrating the front and back surfaces are formed at predetermined intervals at the edge of the. The core through-hole 12 is a portion to which a locking portion of a foam described later is fitted. The core through-hole 12 is used for forming the locking portion at the time of molding the molded product and for releasing a foaming gas of a foaming raw material. .

The size and the number of the core through-holes 12 are such that the foamed gas and the like escape and the foaming material enters and leaks in an appropriate amount so that the formed foam does not cause voids or underfill. It is determined according to the composition of the foaming material to be used and the like. Usually, holes of about 0.5 to 2.5 mm are provided at intervals of 150 to 200 mm. The edge of the core 11 of this embodiment is made thin by providing a step on the surface side (the surface on the side of the foam with skin).
Next, an edge portion of the skin 27 described later is arranged. Thereby, the height of the edge of the skin 27 and the surface of the core 11 adjacent to the edge are made substantially equal, and the foaming raw material collides with the edge end surface of the skin 27 during foam molding, and the flow of the foaming raw material is reduced. This prevents the edge of the skin 27 from being hindered or being bent further inward due to the collision.

The foam with skin 21 comprises a foam 23 and a skin 27 covering the surface and side surfaces of the foam 23 and is fixed to the surface of the core 11. The foam 23
Is made of polyurethane foam or the like, and the core through hole 1
2 and a protruding foam engaging portion 25 which is fitted in a skin through-hole 29 described later and adhered to the back surface of the core 11. The foam 23 is formed by foaming between the skin 27 and the surface of the core 11. The foam 23 adheres to the front surface of the core 11 and the back surface of the skin 27 by self-adhesive force at the time of foaming. The stopper 25 is securely fixed by locking.

The skin 27 has an edge 28 bent in a substantially U-shape toward the back of the skin, and is adhered to the foam 23 so as to cover the front, side and back edges of the foam 23. In addition, the core through hole 1 is provided at the edge 28 of the skin.
A skin through-hole 29 penetrating the front and back surfaces of the skin is formed in accordance with the position 2, and the engaging portion 25 of the foam is fitted.
FIG. 3A shows a plan view of an example of the skin through-hole 29, but the through-hole 29 is not limited to a circular shape. Further, a cutout 29a may be provided from the end of the edge 28 of the skin as shown in FIG. In addition,
Various materials are used for the material of the skin 27,
Use is made of plastic leather or a liquid-impervious material in which a plastic film or the like is laminated on the back surface of the fabric.

The molded article 10 having such a configuration
Since there is no side wall of the concave portion of the core, which has conventionally existed on the outer periphery of the foam 21 with the skin, the design flexibility of the foam with the skin is high. Furthermore, when this molded article is attached to a counterpart article, since the side wall of the concave portion of the core does not exist, the side face of the foam 21 with skin can be brought into close contact with the counterpart article, and the foam 21 with skin and the counterpart article The appearance of the boundary portion with becomes good.

Next, an embodiment of the method for producing the molded article will be described. 4 to 7 are cross-sectional views showing a state at the time of manufacturing. The same components as those described above are denoted by the same reference numerals. First, as shown in FIG. 4, the core 11 having a core through-hole 12 at the edge of the attachment portion of the foam with skin is provided.
The outer skin 27 having a skin through-hole 29 formed by bending the edge 28 in a substantially U-shape toward the rear surface side is disposed on the lower mold 33. Reference numeral 40 denotes a foaming material injection nozzle.

In this embodiment, the foam material inlets 14 and 32 are provided in the core 11 and the upper mold 31. Further, on the mold surface of the upper mold 31, a concave groove 34 for gas release is formed at a portion where the core through-hole 12 is located. The concave groove 34 is formed continuously so that each of the core through holes 12 communicates. Instead of the concave groove 34, a concave portion corresponding to each of the core through holes 12 may be formed independently without being continuous. These grooves 34 or recesses allow the foaming gas to easily escape to the back side of the core 11 through the core through-holes 12, and the foaming material that has entered the core through-holes 12 at the time of foaming has the grooves 34 or recesses. In core 11
It extends to the back surface side so that the locking portion 25 having an anchor effect can be formed.

When the core 11 and the skin 27 are arranged, the skin 27 has the back side facing upward, while the core 11 has the front side facing downward, and the core through hole 12 has the upper mold 31.
And the upper and lower dies 31 and 33 are arranged such that the skin through-hole 29 and the core through-hole 12 communicate with each other when the upper and lower dies 31 and 33 are closed. Note that the core 11 is arranged by fitting a clip (not shown) or the like previously attached to the back surface of the core 11 into a clip fitting hole (not shown) provided on the mold surface of the upper die 31 or the like. .

Subsequently, the upper mold 31 and the lower mold 33 are closed as shown in FIG. Due to this closed mold, the edge 2 of the skin 27
8 surface comes into contact with the surface of the core 11, and the skin through-hole 29,
The core through hole 12 and the concave groove 34 of the upper die 31 are in communication with each other. Further, at the time of closing the mold, the edge 28 of the skin is bent in a substantially U-shape and has high shape retention, so that the edge 28 of the skin is less likely to hang down or wrinkle. In addition, even if the edge 28 of the skin may hang down a little, it is pushed up by the foaming pressure shown below and the core 11
There is almost no problem because it is crimped to

Then, a foaming raw material P such as a polyurethane raw material is injected between the skin 27 and the core 11 from the injection nozzle 40. As shown in FIG. 6, the injected foaming raw material P
Foaming occurs between the core 7 and the core 11, and the edge 28 of the skin 27 is pressed against the surface of the core 11 and sealed by the increasing foaming pressure. Further, the foaming gas generated from the foaming raw material P and the air trapped between the skin 27 and the core 11 at the time of closing the mold pass through the skin through-hole 29 and the core through-hole 12 and the upper mold 31.
Escape into the concave groove 34 on the mold surface. In addition, the skin 27
The foaming raw material P filled between the core 11 and the core 11 leaks into the concave groove 34 of the upper mold 31 through the skin through hole 29 and the core through hole 12 as shown in FIG. The amount of leakage at this time is
The size, number, and the like of the skin through-holes 29 and the core through-holes 12 are determined in advance according to the viscosity and the like of the foaming material to be used so that the foaming material between the core 11 and the foaming material does not run short.

The foaming raw material P is then cured to form a foam 23 integrated with the skin 27 and the core 11 by self-adhesion, and the portion that has entered the skin through-hole 29 and the core through-hole 12 is formed. It becomes the locking portion 25 of the foam.
Thereafter, when the upper mold 31 is separated from the lower mold 33 and the molded article is released, a molded article similar to the molded article 10 shown in FIGS. 1 and 2 is obtained.

In the above embodiment, the molded article was manufactured by the closed injection method in which the foaming material was injected in a closed state. However, the foaming material was injected with the upper mold and the lower mold open, and then the mold was closed. An open injection method may be used.

[0029]

As shown and described above, according to the present invention, since there is no side wall of the concave portion of the core around the foam with the skin, the degree of freedom in design is high, and when the fiber is attached to the counterpart article, There is no fear that the aesthetic feeling is impaired by the interposition of the side wall. In addition, the engaging portion of the foam fits into the skin through hole formed in the edge of the skin and the core through hole formed in the core, and the foam is adhered to the core and the skin, so that the skin is not provided. The foam does not come off or rise.

On the other hand, in the manufacturing method, since the edge of the skin is pressed against the core by the foaming pressure on the back side of the molded article to seal the edge of the skin, the leakage of the foaming material on the front side of the molded article does not occur. And the surface appearance of the molded article is good. Moreover,
Since sealing is performed on the back side of the molded product, the thickness of the foam with skin can be reduced, and the degree of freedom in design is further increased. Further, the foam gas escapes from between the skin and the core to the outside through the skin through-hole formed in the edge of the skin and the core through-hole formed in the core on the back side of the molded product, so that a void is generated in the foam. And a good molded product is obtained.

Further, there is an advantage that the foam with skin can be provided on the entire surface of the core or can be provided partially. In addition, since the foam with the skin is integrated with the core simultaneously with the molding of the foam with the skin, there is no need to assemble the foam with the skin into the core in a later process, making it extremely easy to manufacture and inexpensively produce a molded product. it can.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a plastic molded article having a foam with a skin on the surface according to one embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part thereof.

FIG. 3 is a plan view showing an example of a skin through-hole or a cutout.

FIG. 4 is a cross-sectional view showing an example of a manufacturing method of the present invention when a skin and a core are arranged.

FIG. 5 is a cross-sectional view of a molding die after injection of a foaming raw material at the time of its production.

FIG. 6 is a partially enlarged sectional view thereof.

FIG. 7 is a sectional view showing a state after completion of foaming.

FIG. 8 is a sectional view showing a conventional product.

FIG. 9 is a sectional view showing another example of a conventional product.

FIG. 10 is a partial cross-sectional view showing a conventional manufacturing method.

[Description of Signs] 10 Molded product 11 Core 12 Core through hole 21 Foam with skin 23 Foam 25 Locking part 27 Skin 29 Skin through hole 31 Upper mold 33 Lower mold 34 Groove P Foaming material

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B29C 39/10 B29C 39/22-39/28 B32B 3/00-3/06

Claims (3)

(57) [Claims] 1. A plastic molded product having a foam with a skin on the surface of a core, wherein the core has a core through hole penetrating the front and back surfaces at an edge of a mounting portion of the foam with a skin, The foam has an edge portion having a skin through-hole or notch penetrating the front and back surfaces, is bent toward the back surface in a substantially U-shaped cross section, and the skin through-hole or notch is aligned with the core through-hole, and An outer surface having an edge surface in contact with the surface of the core, and a space between the outer surface and the core, which is adhered to the outer surface and the core, and a part of the outer surface fits into the core through hole or the notch through the cutout. A plastic molded article having a foam with a skin on its surface, characterized in that the molded article comprises a foam that has become a locking portion. 2. A skin is arranged on a lower mold surface and a core is arranged on an upper mold surface, and a foam material injected between the skin and the core is foamed to form a foam integrally with the skin and the core. A method for manufacturing a plastic molded product having a foam with a skin on the surface by forming the skin, wherein the skin has an edge having a skin through hole or a notch penetrating the front and back surfaces, and the back surface has a substantially U-shaped cross section. The core is provided with a core through-hole that penetrates the front and back surfaces at the edge of the foam-attached part with a skin, and the core is formed by bending the core through the core through-hole. Align the position and place the skin on the lower mold surface such that the bent edge surface of the skin comes into contact with the surface of the core,
A method for producing a plastic molded article having a foam with a skin on its surface, wherein the core is disposed on a mold surface of an upper mold, and a foaming material is foamed between the skin and the core. 3. The foamed body with a skin on the surface according to claim 2, wherein a concave groove or a concave portion for allowing foaming gas to escape is provided in the upper mold surface portion where the core through hole is located. Manufacturing method of plastic molded products.