JPS601193B2 - Manufacturing method of composite molded body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a composite molded article comprising sequentially laminating a base layer, a cushioning material layer, and a skin material layer.

For example, vehicle interior parts such as door trims, front seat panels, ceiling lining panels, dashboards, etc. are generally made of hard materials with appropriate strength and rigidity (Figure 1).
A composite molded article having a three-layer lamination structure is used, in which the surface is covered with a soft material, a cushion layer 2, and a decorative/protective skin layer 3.

Composite molded bodies having the above-mentioned layer structure are also frequently used in various other interior materials for buildings, furniture, exterior members for electrical appliances, and the like. Generally, the above-mentioned composite molded products are made from a laminated flat plate in which the constituent layers 1, 2, and 3 are laminated together in advance, and are processed by vacuum forming, press working, pressure forming, or other methods.
It is molded into the desired shape using a mold using a plug molding method or the like.

Then, at the same time as this molding or after demolding, unnecessary twill portions around the molded body are cut and removed (trimmed). There are some products that can be completed by trimming this unnecessary green area, but if only trimming is done, the laminated end faces of each layer 1, 2, and 3 will be exposed on the cut surface (outer peripheral end face of the composite molded body) 4, resulting in poor appearance. ,
Products with reinforcing wire mesh are dangerous because the green wire mesh is exposed on the cut surface 4, and each layer is likely to peel and peel at both cut ends. The cut surface of the product is concealed and the edges are finished to create the final product.

In this case, the form of concealment treatment for the cut surface 4 is to extend the circumference of the skin layer 3 as shown by the chain line in FIG.
It is best to cover and hide the cut surfaces of the cushion layer 2 and the base body 1 by folding it back to the back side of the molded body and fixing it with an adhesive or the like, which will give the best appearance and a beautiful green finish.

However, in the case where a composite molded body is obtained using a laminated flat plate in which the constituent layers 1, 2, and 3 are laminated together in advance as in the conventional method, the edge finishing treatment as shown by the chain lines in FIG. In order to do this, the molded body is trimmed to a size that is one size larger than the predetermined external dimensions of the molded body, and then the above-mentioned extra dimensions are trimmed from the green base 1 and cushion layer 2 portions around the molded body to form a skin. This is an extremely inefficient operation in which the layer 3 is removed from the back surface and the skin layer periphery 3', which has become extended as a result, is folded back to the back side of the molded article and stopped, which cannot be used in practice.

Conventionally, for products that require concealment of the cut surface 4, a separately produced molding material is attached around the edge of the trimmed molded body to hide the cut surface 4 and produce the final product. The installation process requires materials and labor, resulting in high costs. Furthermore, the edges of the molded body are often framed with molding material, which is not preferred as a form. In view of the above, an object of the present invention is to mass-produce efficiently and inexpensively a composite molded article having an edge treatment configuration as shown by the chain line in FIG. 1 without using a molding material.

A detailed explanation will be given below based on the drawings.

First, the mold configuration used in the present invention will be explained. 5,6
5 is a split mold for manufacturing a composite molded body, and 5 is a first mold for molding the front side of the composite molded body, and 6 is a second mold for molding the back side of the composite molded body.

When both molds 5 and 6 are clamped, the opposing molding surface 5
Forming with a gap size d that is approximately equal to the sum of the thickness d3 of the skin material 3 after vacuum forming and the thickness d2 of the cushion material 2 after vacuum forming between 1 and 61 (slightly smaller is actually acceptable). The cavity is designed so that a cavity 7 (FIGS. 4 and 5) is formed. Both molds 5 and 6 are provided with a vacuum forming function by closing a number of vacuum holes 52 and 62 on their molding surfaces, respectively.

Further, a hole 63 for injection or pressure feeding of the molten resin is opened in the molding surface 61 of the second mold 6. Then, when the skin material 3 and the cushion material 2 are vacuum-formed using the two molds as described later, and then the molds are clamped (FIG. 4), the two molds face each other around the outer periphery of the forming surface areas 51 and 61 of the two molds. Between the surfaces 51' and 61', there is a skin material part 3' and a cushion material part 2 interposed therebetween.
The mold structure is such that a gap 8 is created so that the two parts are not pressed against each other. In the illustrated example, the surface 61' on the side of the mold 6 is formed into an inclined surface to form a tapered gap 8. Numerals 54 and 64 are vacuum suction holes closed in the surfaces 51' and 61' of both molds 5 and 6, and 65 is a thin pipe for venting provided on the mold 2 side, which will be described later.

Next, the manufacturing process will be explained step by step.

'1l First step (Fig. 2) With the first and second molds 5 and 6 opened, the first mold 5 molds the skin material 3, and the second mold 6 molds the cushion material 2. Vacuum forming is performed and the molding materials 3 and 2 are held as they are on the mold surface.

The skin material 3 is made of various soft or semi-hard resin sheets, cloth with Z heat elongation with the back side lined with a resin sheet, European synthetic leather, etc., and the cushion material 2 is made of various kinds such as vinyl chloride, polyethylene, polypropylene, etc. Foam sheets with good rebound resilience, polyurethane foam felt lined with resin sheets, etc. can be used.

When the skin material 3 is a soft resin Z resin sheet, by carving a desired uneven pattern such as grain on the molding surface of the first mold 5 in advance, the uneven pattern can be clearly formed on the surface material 3. The composite molded article shown can be obtained. Note that adhesive 9 is applied to the back surface of the skin material 3 and/or the surface of the cushion material 22 in advance.

It is convenient for the handling of the materials 3 and 2 that the adhesive 9 is activated by the heat when the materials 3 and 2 are softened and heated for vacuum forming. 13 is a sealing clamp for vacuum forming each of the materials 2 and 3.

2{2} Second step (Figs. 3 and 4) The first and second surfaces are formed by vacuum forming and holding the skin material 3 and the cushion material 2, respectively.
The molds 5 and 6 are clamped (Fig. 4).

By this mold clamping, the back surface of the skin material 3 and the surface of the cushion material 2 are pressed into contact with each other in the effective molding surface area, and are integrated via the adhesive 9. That is, the gap size d between the opposing molding surfaces of the molding cavity 7 formed by mold clamping is determined by the thickness d3 of the skin material 3 after vacuum forming and the cushioning material 2.
Since the dimension after vacuum forming is approximately equal to 3 plus the thickness after vacuum forming, by clamping the molds 5 and 6, the skin material 3 and the cushion layer 2 have a gap between them in their effective molding surface area. They are brought into pressure contact and integrated via the adhesive 9 without causing any friction. 4 However, regarding the material parts 3' and 2' around the outside of each effective molding surface area of the skin material 3 and the cushion material 2, care should be taken not to press the material parts 3' and 2' together when the mold is clamped as described above. Since the mold is constructed such that a gap 8 is created between the opposing surfaces 51' and 61' of both molds due to the outer periphery of the effective molding surface area of the molds, the parts 3' and 2' are kept separated from each other. In order to ensure this separated state, vacuum suction holes 54 and 64 are respectively closed in the facing surfaces 51' and 61' of both molds around the outside of the effective molding surface area of the skin material 3 and the cushion material 2. It is possible to actively suction and hold each portion 3', 2' to the die facing surface 51', 61', respectively. Also, the skin material 3 and the cushion material 2
In the process of pressing the skin material 3 and the cushion material 2 together by mold clamping in order to closely integrate the effective molding surface areas of the skin material 3 and the cushion material 2 without causing any air accumulation therebetween, the space between the skin material 3 and the cushion material 2 is It is possible to tighten the mold while actively removing air from the mold.

In the illustrated example, a thin air venting pipe 65 is provided in the second mold 6 by penetrating it back and forth so that it can freely move forward and backward, and when vacuum forming the cushioning material 2, the pipe 65 is moved backward to remove the tip of the pipe 65. This is done by holding it substantially flush with the molding surface 61 (Fig. 2)
. After vacuum forming, the pipe 65 is moved forward to penetrate through the thickness of the cushioning material 2 and expose the closed end of the pipe to the surface of the cushioning material 2 (Fig. 3), and while sucking air from the opening, The air between the skin material 3 and the cushion material 2 is actively removed by clamping the mold 6 and the first mold 5 that holds the skin material 3 after vacuum forming (Fig. 3 → Fig. 4). This shows a device that vents air to prevent air accumulation. After mold clamping is completed, the pipe 65 is moved backward to return the pipe tip to a position flush with the molding surface 61 (Fig. 4).
. In addition, if a method is adopted in which long materials 2 and 3 are fed out and introduced between the molds 5 and 6 while being fed intermittently, each material is cut by a cutting device not shown in the figure after the above-mentioned clamping is completed. Cut the edges with subsequent material parts. 31 Third step (Fig. 5) After the mold clamping is completed, the mold clamping state is maintained as it is, and molten resin (for example, polyprolene resin, etc.) is injected into the mold from the resin injection or pressure feeding hole 63 of the second mold 6. (resin, etc.) is press-fitted.

Then, the press-fit resin compresses the cushion material 2 in the direction of the skin material 3 against the elasticity of the cushion material 2 and enters between the back surface of the cushion material 2 and the molding surface 61 of the mold 6. As a result, the resin base layer 1 is integrally formed on the back surface of the effective molding surface area of the cushion material 2. The thickness d of the base layer 1 is the thickness d2 of the cushion material 2 before resin press-fitting, and the thickness d2 (
The thickness is approximately equal to the difference between the two (Fig. 5).

Also, due to the pressing force of this resin, the cushioning material 2 and the skin material 3 between the molds 5 and 6 are strongly pressed, and the bonding of both 2 and 3 is strengthened. The entire surface is pressed and adhered to the surface 51, and good molding is delayed even in details such as highlighted areas.

The cushioning material layer 2 and the base layer 1 are integrated by heat fusion.

In this case, there is a risk that the cushioning material layer 2 and the base Z layer 1 are made of materials that have poor mutual heat fusion properties, or that the cushioning material layer 2 may melt due to the heat and pressure of the molten resin press-fitted into the mold. In the case where the cushioning material layer 2 has a bonding layer and a heat insulating layer on the back surface thereof, the cushioning material layer 2 has mutual thermal fusion properties with the base layer 1 as an adhesive layer and a heat insulating layer. For example, it may be integrally lined with a similar hard or semi-hard solid resin sheet (not shown). Further, when the molten resin is press-fitted between the molds 5 and 6, the back surface portion of the cushioning material 22 facing the molten resin press-fitting hole 63 receives the resin press-fitting pressure and heat most strongly.

As a result, if there is a risk of local melting of the cushioning material in that area, place a heat shielding/pressure-resistant piece of an appropriate size and thickness on the molding surface area of the mold 6 centering on the resin press-fit hole 63 in advance. -10.For example, it is a good idea to attach a piece of metal sheet or cardboard with adhesive on both sides. As the metal sheet piece, for example, an aluminum sheet is suitable because it is flexible. That is, when the resin is press-fitted into the mold, the heat shielding/pressure-resistant piece 10 is moved away from the molding surface 61 by the resin pressure coming out of the hole 63 and attached to the back surface of the cushioning material 2 facing the hole 63. The pressure and heat of the molten resin on the back surface of the cushioning material is alleviated. As shown in FIG. 6, one of the pieces is finally embedded between the cushioning material layer 24 and the base layer 1. The attachment of the piece 10 to the molding surface 61 may be automated using a robot or the like. In addition, if there is a risk that the molten resin press-fitted into the mold may enter the vacuum forming hole 62 closed to the molding surface 61 of the mold 6 or the hole of the venting pipe 65, for example, All you have to do is attach an on-off valve to the tip of the valve.

As an example, FIG. 8 shows that the opening of the molding surface is normally closed at the tip of the vacuum forming hole 62 by the pressing force of the spring 11 (dashed line), and during vacuum suction, the suction force is used to internally resist the elasticity of the spring 11. This device is equipped with a valve 12 (solid line) that opens the molding surface by being pulled toward the molding surface. During resin press-fitting, compressed air is sent into the vacuum hole 62 in the opposite direction, so that the vacuum opening on the molding surface is tightly closed. Intrusion of the resin into the round holes 62 is prevented.

An on-off valve similar to the above may be provided at the tip of the air venting pipe 65 to feed compressed air into the pipe 65 during resin press-fitting to keep the pipe tip closed in the open state. Or the ninth
As shown in the figure, the effective molding surface 61 of the second mold 6 is covered with a fine continuous porous surface member 14.

The porous surface member 14 is formed by thermally spraying a metal such as an alloy of aluminum, zinc, etc. on a model mold surface such as a wooden mold having the shape of the effective molding surface 61 of the second mold 6, for example, to form fine metal particles. A thin surface part corresponding to the shape of the molding surface 61 can be obtained with the fine open-pore porous texture that has been deposited.
The molding surface 6 of the second mold 6 is made into a template from the model mold surface.
All you have to do is berth on board 1. Through holes are previously formed in the surface member 14 in a surface portion corresponding to the injection or press-in hole 63 for the molten resin and the inlet/outlet hole for the venting pipe 65. As described above, when the effective molding surface 61 of the second mold 6 is covered with both porous fleshy members 14 and the vacuum hole 62 is brought into an air suction state, the outside air is sucked through the bolus fleshy of the porous fleshy fillet member 14. Vacuum forming of the cushion material 2 is carried out without any problems. Further, when the molten resin is injected, unless the pressure is extremely high, the molten resin will not enter the porous flesh of the face member 14, and therefore the molten resin will be prevented from entering the vacuum holes 62. As for the venting pipe 65, as shown in FIG. 5, if the molten resin 1 is injected or press-fitted while the closed end of the pipe 65 is held in a state in which it protrudes into the cushioning material layer 2, the pipe is forced to open. There is no need to install the above-mentioned on-off valve at the tip of 65.

Of course, it will be more effective if a valve is provided. ■ Fourth step (Figures 6 and 7) After the base layer 1 formed by pouring the molten resin is sufficiently hardened by cooling, the parts 3' and 2' of the skin material and cushion material are removed by the vacuum suction holes 54 and 64. Stop holding the suction and open the mold to take out the molded product.

As shown in Figure 6, the molded product has three parts, the base layer 1, the cushioning material layer 2, and the skin material layer 3, joined together in the effective molding area, and the cushioning material part 2' on the outer periphery and the skin material layer 3 are joined together in the effective molding area. The material portions 3' are separated from each other. Furthermore, if the adhesive layer 9 on the surfaces of the portions 2' and/or 3' is activated by heat, it will cool down and lose its adhesive properties during the cooling period of the base layer 1; Even if they come into contact with each other, mutual adhesion will not occur. When the cushioning material layer 2 is opened, it returns from the compressed state d2' to approximately the original thickness state d2 due to its own elastic force.
The state will be restored to . Therefore, after taking out the molded product, the cushioning material portion 2' of the outer box of the effective molding area is removed by cutting 13-13 (FIG. 6) along the periphery of the base layer 1.

In this case, the base of the cushion material portion 2' is the skin material portion 3.
Even if it is adhered to the root part of ' with adhesive 9, the adhesive width is small, so by pulling the cushioning material part 2' a little forcefully, it can be easily and beautifully separated and removed from the skin material part 3'. be able to. Should the skin material part 3' be left as is? Alternatively, trimming is performed leaving only the extension width 1 required for commercialization. and extended skin material portion 3 around the molded body.
The final product is obtained by folding (wrapping) this onto the back side of the base body 1 and fixing it to the back face of the base body with an adhesive or a suitable fastener as shown in FIG. 7.
As described above, according to the method of the present invention, {a) Since the skin material part 3' and the cushion material 2' part around the outer area of the effective molded part can be obtained in a form that is separated from each other from the beginning, the cushion material part 2' is extremely easy to remove, and therefore the end face 4 of the molded product is covered by folding the extension piece 3' of the skin layer 3, resulting in a molded product with a nice and beautiful green finish (Figs. 1 and 7). can be obtained easily and efficiently.

(b} The molded product body is obtained by vacuum forming the skin material 3 and the cushioning material 2 using the molding surfaces 51 and 61 of the injection molds 5 and 6, respectively, and then pressing them together by clamping the molds. Since the base layer 1 is injection molded on the back side of the base layer 1 and integrated, each layer is sequentially molded and laminated, so the molded shape is more consistent and the highlighted areas are clearer than when vacuum forming a composite material of three layers and one layer. Sharp molded products can be easily obtained.

'c} Because the cavity gap dimension d between the molding surfaces 51 and 61 when the mold is clamped is approximately the same as the sum of the thickness d3 of the skin material 3 and the thickness of the cushion material 2 after vacuum forming. By clamping the mold, the effective molding surface areas of the skin material 3 and the cushion material 2 are fully integrated with each other through the adhesive layer 9, and are further pressed by the pressure of the molten resin injected for molding the base layer 1. A product with enhanced adhesion and no delamination can be obtained.

In addition, by actively removing air between the skin material 3 and the cushion material 2 during mold clamping, it is possible to manufacture a product with no so-called air pockets between the layers 3 and 2. [d1 The cushion material and the skin material, which are the waste materials removed by trimming, are each separated separately, so they can be recovered and reused (for example, melted and reused), reducing material costs and eliminating any waste.

'e} Heat softening treatment of the skin material 3 and cushion material 2 → Introduction of both materials 3 and 2 into the molds 5 and 6 → Vacuum forming of both materials 3 and 2 → Mold clamping → Press-fitting of molten resin → Mold It is easy to automatically and continuously open the opening cycle, and the desired molded products can be mass-produced at low cost.

The following effects can be obtained, and this method is effective and suitable as a method for producing this type of laminate molded product.

Incidentally, in the molding surface of the mold 6, a groove (not shown in the figure) for forming reinforcing convex ribs may be formed on the back surface of the base layer 1, and in this case, a vacuum hole 62 is closed in the groove. By preventing the groove from forming, the presence of the groove does not harm the vacuum forming of the cushion material 2 in any way.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of an example of the product, Fig. 2 is a cross-sectional view of a state in which the skin material and cushioning material are vacuum-formed, and Fig. 3 is a cross-sectional view of a part of the state in which the mold is clamped while releasing air. Figure 4 is a cross-sectional view of a part of the mold after it has been closed, Figure 5 is a cross-sectional view of a part of the molded product after the molten resin has been injected, and Figure 6 is an enlarged cross-section of a part of the molded product taken out after opening the mold. Figure 7 is the same figure with the edges treated; Figure 8 is an enlarged sectional view of the on-off valve provided at the tip of the vacuum hole; Figure 9 is the second mold molding surface covered with a porous surface member. 1 is a base layer, 2 is a cushioning material layer, 3 is a skin layer, 5, 6
is a mold. 1st figure 3rd figure rhombus? Figure 5, Figure 6, Figure 7

Claims (1)

[Scope of Claims] 1. In obtaining a composite molded article consisting of a base layer 1, a cushion material layer 2, and a skin material layer 3, which are successively laminated, a skin layer (described later) is formed between the opposing effective molding surfaces 51 and 61 when the mold is clamped. The first molding cavity 7 for forming the surface side of the composite molded body is configured with a molding cavity 7 having a gap size d approximately equal to the sum of the thickness d_3 of the material 3 after vacuum forming and the thickness d_2 of the cushion material 2 after vacuum forming. A mold 5 and a second mold 6 for back side molding are prepared, and both the molds 5 and 6 are each equipped with a vacuum forming function, and the molding surface 61 of the second mold 6 is The injection or pressure feeding hole 63 for molten resin is opened, and when the skin material 3 and cushion material 2, which will be described later, are vacuum-formed and clamped using both molds 5 and 6, the effective molding surface area of both molds is Both mold facing surfaces 51 on the outer periphery
A gap 8 is formed between ' and 61' so as not to press the skin material part 3' and cushion material part 2' interposed therebetween, and the skin material 3 is formed by the first mold 5. , the cushion material 2 is vacuum-formed using the second mold 6, and the molds 5 are then molded while the molding materials are held in the respective molds.
, 6, the skin material 3 and the cushion material 2 are pressed against each other in the effective molding surface area and bonded together via the adhesive 9 previously interposed between them. The molten resin injection area is formed between the molding surface 61 of the mold 6 and the cushion material 2 surface by press-fitting the molten resin from the pressure feeding hole 63 against the elasticity of the cushion material 2.
The base layer 1 is formed and deposited on the back side of the effective molding surface area to produce a composite molded body consisting of the base layer 1, cushion material layer 2, and skin material layer 3 sequentially laminated, and then the mold is opened to take out the composite molded body. The material portion 2' of the cushion material layer 2 outside the effective molding area is trimmed, and the material portion 3' of the skin material layer 3 around the outside of the effective molding area is folded back to the back side of the base layer 1 and fixed. A method for manufacturing a composite molded article. 2 In the process of pressing the skin material 3 and the cushion material 2, which are vacuum-formed and held in the first and second molds 5 and 6, respectively, by the mold clamping of the molds 5 and 6, the skin material 3 and the cushion material The air between the two was actively vented. A method for manufacturing a composite molded article according to claim 1. 3
Vacuum suction holes 54 are provided in the opposing surfaces 51' and 61' of the effective molding surfaces 51 and 61 of the first and second molds 5 and 6, respectively.
64 is opened, and the skin material 3 and cushion material 2 are inserted into both molds 6.
, 6, the skin material portion 3' intervening in the gap 8 between the facing surfaces of both molds around the outer periphery of the effective molding surfaces of both molds.
2. The method of manufacturing a composite molded article according to claim 1, wherein the cushion material portions 2' and 2' are actively held apart from each other by the suction force of the vacuum suction holes 54, 64, respectively. 4. As the second mold 6, a mold whose effective molding surface 61 is covered with a continuous microporous porous surface member 14 is used. A method for manufacturing a composite molded article according to claim 1.