JP3203846B2 - Manufacturing method of laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a laminate in which a heat-softening sheet molding is laminated on a low-density molding.
More specifically, the present invention relates to a method for producing a laminate suitably used for automotive interior materials such as dash insulators and floor insulators, various sound insulating materials, sound absorbing materials, cushioning materials and the like.

[0002]

2. Description of the Related Art In the case of manufacturing a laminate in which a heat-softening sheet molded article is laminated on a low-density molding such as a fiber assembly, conventionally, the heat-softening sheet has to be vacuumed beforehand. The desired shape is formed by a molding method, a compressed air press method or a press molding method, and the heat-softenable sheet molded body and the low-density molded body are bonded in a mold different from the mold in which the heat-softenable sheet is molded. (Japanese Unexamined Patent Publication No. 2-95838)
And so on.

[0003] However, the manufacturing method of the above-mentioned laminate is as follows.
Two steps, a step of forming the heat-softening sheet and a step of bonding the sheet to the low-density formed body, are required, so that the production efficiency is low. Further, the bonding between the heat-softenable sheet molded body and the low-density molded body is performed by externally applying pressure to these in a mold, but the low-density molded body such as a fiber assembly is Since it is easily deformed by pressure, the low-density molded product may be locally overpressurized during bonding using the mold. For this reason, the locally overpressed portion of the low-density compact has a higher density than the other portions, resulting in inferior soundproofing performance and the like, and has a problem that the mold is lost.

[0004] The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a method for manufacturing a laminated body capable of industrially and advantageously performing molding of a heat-softenable sheet and bonding of the heat-softenable sheet molded body and the low-density molded body.

[0005]

Means for Solving the Problems In order to achieve the above object, the present inventor has set forth, as a first invention, a method of manufacturing a laminate formed by bonding and laminating a heat-softening sheet compact on a low-density compact. In this case, the low-density molded body is placed in the cavity of the lower mold, and an adhesive or a pressure-sensitive adhesive is applied to the upper surface of the low-density molded body, while the suction is engaged with the upper surface of the low-density molded body and communicates with the inside. A heat-softening sheet is supplied to the lower surface of a vacuum forming die having a lower surface with holes formed therein, and the sheet is heated. The sheet is sucked, the sheet is formed into a shape corresponding to the lower surface of the vacuum forming die, and then the heat-softening sheet molded body is pressed against the upper surface of the low-density molded body,
Provided is a method for manufacturing a laminate, which is characterized by bonding.

Further, as a second invention, in manufacturing a laminated body formed by bonding and laminating a heat-softening sheet molded body on a low-density molded body, the low-density molded body is pressed against a pressing force from above. The low-density molded body is disposed in a cavity of a lower mold having an elastically deformable cushion body, and an adhesive or a pressure-sensitive adhesive is applied to an upper surface of the low-density molded body. Pressing the heat-softening sheet molded body molded into
Provided is a method for manufacturing a laminate, which is characterized by bonding.

Further, as a third invention, in manufacturing a laminated body obtained by bonding and laminating a thermo-softening sheet molded body on a low-density molded body, the low-density molded body is resistant to pressing force from above. And placed in the cavity of the lower mold having a cushion body that can be elastically deformed, while applying an adhesive or a pressure-sensitive adhesive to the upper surface of the low-density molded body, engaging with the upper surface of the low-density molded body, and A heat-softening sheet is supplied to the lower surface of a vacuum forming die having a lower surface on which a communicating suction hole is formed, and this is heated and, at the same time, the inside of the vacuum forming die is vacuum-sucked, so that the heat-softening sheet is supplied through the suction hole. The heat-softening sheet is sucked, the sheet is formed into a shape corresponding to the lower surface of the vacuum forming die, and then the heat-softening sheet molded body is pressed and adhered to the upper surface of the low-density molded body. To provide a method for producing a laminated body

[0008]

According to the first aspect of the present invention, the step of forming the heat-softening sheet and the step of bonding the sheet to the low-density formed body can be performed in one step, thereby increasing the production efficiency. According to the second aspect of the present invention, since the pressure applied to the low-density molded product of the heat-softening sheet molded product is evenly performed by the elastic action of the cushion body, the upper and lower shapes of the low-density molded product are different. Even in such a case, pressure can be applied uniformly without losing the shape of each part, and partial overpressurization of the low-density molded body is eliminated as much as possible, and one part of the low-density molded body is replaced with another part. Without becoming denser than
Since the low-density state can be maintained uniformly and the shape does not collapse, a laminate having a desired shape can be easily and reliably manufactured. Therefore, the laminate according to the present invention is suitably used as a sound insulating material or the like.

In particular, according to the third aspect of the present invention, such a laminate can be produced more industrially and advantageously.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for producing a laminate according to the present invention comprises laminating a low-density molded body and a heat-softening sheet molded body while applying pressure to the low-density molded body using an adhesive or a pressure-sensitive adhesive. The low-density molded product used in the present invention preferably has a soft average apparent density of 0.04 to 0.15 g / cm ³ , and if the average apparent density is in this range, the material is particularly limited. Although not a thing, the fiber distribution is 3
A fiber obtained by mixing a binder into short fibers having a denier of 0 or less and a cut length of 10 to 100 mm is suitably used.

The type of the fiber may be any of inorganic fiber, organic fiber, natural fiber and synthetic fiber, but practically, polystyrene, polypropylene, polyester, polyamide, rayon, vinylon, acryl, polyurethane, acetate , Cupra, cellulose, cotton, wool, hemp and the like are used. These may be used alone or in combination of two or more.

As the binder, powder or fiber having a melting point lower than the melting point of the fiber material is preferably used. Generally, thermoplastic polyethylene, polypropylene, or the like is used.
Polyester, polyamide, polyvinyl chloride, EVA
(Ethylene vinyl acetic acid copolymer), resins such as polyurethane, bituminous powder and fibers are used. Further, a thermosetting resin such as a phenol resin is also used. Further, as the binder, a composite fiber shape called a sheath-core type or a side-by-side type may be used. 1 binder
The species may be used alone or in combination of two or more. Usually, the compounding ratio of these binders is preferably 5 to 40% by weight, particularly preferably 5 to 20% by weight of the fiber material.

Incidentally, such a low-density molded article can be produced, for example, by the method described in JP-A-2-95838.

On the other hand, the heat-softening sheet is not particularly limited as long as it has a heat-softening property.
A thermoplastic resin sheet having sound insulation properties is preferably used in terms of performance, cost, ease of molding, and the like, and further, an inorganic filler such as calcium carbonate is blended, and a thermoplastic resin sheet having an increased density is used. In this case, the sound insulation performance is further improved. Specifically, a sheet of polyvinyl chloride, polyethylene, polypropylene, or the like can be used as the thermoplastic sheet, but polyvinyl chloride is preferably used from the viewpoint of performance and productivity. The density of these heat-softening sheets is not less than 1.2 g / cm ³ , especially from 1.5 to 2.
It is preferably 5 g / cm ³ . When a polyvinyl chloride sheet is used as the heat-softening sheet, it is preferable that the sheet is heated to 100 to 150 ° C. in view of ease of molding.

The adhesive and pressure-sensitive adhesive for adhering the low-density molded article and the heat-softening sheet are not particularly limited, and the method of adhesion may be any of point adhesion, line adhesion and surface adhesion. Although a method may be used, when the heat-softening sheet and the low-density molded article are adhered to each other, an acrylic emulsion type is preferably used. In addition, when bonding, tens to hundreds of grams / gram at 60 to 80 ° C. for 5 to 20 seconds.
Preferably, a pressure of cm ² is applied.

Next, an example of manufacturing a laminate according to the present invention will be described with reference to FIG. 1. In FIG. 1, reference numeral 1 denotes a lower mold integrated with a receiving stand. Is provided with a cushion body 4 composed of an airbag 3 having the same shape as the upper surface of the cavity 2 (the lower surface of a low-density molded body 5 described later). The airbag 3 is connected to an air introduction / discharge device (not shown) such as a compressor through an air port (not shown) for introducing air into the inside and discharging the inside air. Can expand into the same shape as the upper surface of the cavity (the lower surface of the low-density molded body 5), and the low-density molded body 5 is placed thereon.

Reference numeral 6 denotes a hollow body 9 having a shape capable of engaging with the upper surface of the low-density molded body 5 and having a lower plate 8 in which a number of suction holes 7 are formed. A vacuum forming die for forming the same shape as the lower plate 7. An air suction device (not shown) such as a vacuum pump is connected to the hollow body 9 through a suction port 10. The air in the hollow body 9 is sucked by the operation of the device.

When a laminate is manufactured using this apparatus, as shown in FIG. 1 (B), a heat-softening sheet 11 is supplied to the lower side of a vacuum forming die 6, and an air suction device is operated. The air in the vacuum forming die 6 is sucked, and the heat-softening sheet 11 is sucked through the suction holes 7.
Is vacuum formed into the same shape as the lower plate 8. In this case, the sheet 11 is heated in advance, or the lower plate 8 of the mold 6 is heated by an appropriate means, whereby the sheet 1 contacting the lower plate 8 is heated.
1 is heated to form and maintain the sheet 11 in a predetermined shape.

On the other hand, a low-density molded body 5 is placed on a cushion body 4 (airbag 3) provided on the cavity 2 of the lower mold 1, and an adhesive or a pressure-sensitive adhesive 12
Is applied.

Next, as shown in FIG.
Same shape as the lower plate 8 of the empty mold 6 (the upper surface of the low-density molded body 5)
The heat-softenable sheet molded body 11 'vacuum-formed into a
Engage and press on the upper surface of low-density compact 5 while maintaining suction
You. At the same time or prior to this,
The air bag 3 is operated to introduce air into the air bag 3, and
Inflate the bag 3 (at this time, the air pressure of the airbag 3
Is 0.1-1 kgf / cm^Two Is preferable).

As a result, the low-density compact 5 made of the heat-softening sheet compact 11 ′ by the cushioning action of the airbag 3.
Pressure is equalized and local overpressurization is eliminated, so that the low-density molded body 5 maintains its surface (upper surface) shape without causing high density due to local overpressurization. Then, the heat-softenable sheet molded body 11 'is bonded to the low-density molded body 5.

FIG. 2 illustrates another method of the present invention. In this example, the lower mold 1 is formed in a plate shape having the same shape as the lower surface of the low-density molded body 1. This lower mold 1
And a plurality of supporting legs 13 are fixed to the lower surface of the lower mold 1, and these supporting legs 13 are attached to the upper wall of the receiving base 1 '. The lower die 1 and the receiving table 1 ′ are respectively inserted into these support legs 13.
The coil spring 14 is wound around the upper wall.
The cushion body 4 is formed by the coil spring 14 in this manner.
Of the coil spring 1 by the pressing force on the low-density compact 5
4 is reduced, the pressing force is equalized by the cushion action, and the local excessive pressurization is eliminated. in this case,
The reaction force of the coil spring is preferably several hundred grams.
Since other configurations, functions and effects are the same as those in FIG. 1, the same components are denoted by the same reference numerals and description thereof will be omitted.

In the present invention, an air bag or a coil spring is used as the cushion body in the above embodiment, but other air cushion mechanisms or mechanical cushion mechanisms may be used. There is no particular limitation as long as the shape of the surface can be maintained without causing it.

In the above embodiment, the heat-softening sheet is vacuum-formed, and is pressed and bonded to the low-density molded body as it is while utilizing the cushioning action of the cushion body. It is also possible to use a heat-softening sheet molded article molded by another mold and press it against a low-density molded article by utilizing the cushioning action of the cushion body. If necessary, the provision of such a cushion body may be omitted, and the vacuum-molded heat-softening sheet may be directly adhered to the low-density molded body to form the heat-softening sheet and adhere to the low-density molded body. By performing it in a process, processing can be performed in a short time, and therefore, product cost can be significantly reduced.

Next, the present invention will be described more specifically with reference to experimental examples.

[Experimental Example 1] 6 to 8 deniers and average length of 4
0 denier polyester fiber, 4 denier, average length 5
A mixture of a low-melting polyester fiber of 0 mm and 20% by weight of the above polyester fiber was molded, and an apparent density of 0.
A porous molded article (low-density molded article) of 08 g / cm3 was obtained.

On the other hand, a polyvinyl chloride sheet having a thickness of 3 mm and a density of 1.7 g / cm ³ was used as a heat-softening sheet.
This was heated to 145 ° C., and an acrylic emulsion-type adhesive was applied to the surface of the porous molded body to obtain a laminate according to the process shown in FIG. That is, the vacuum forming die is lowered by the elevating device, and the polyvinyl chloride sheet is formed by performing vacuum suction. Then, the porous formed body and the sheet formed body are engaged with each other at 80 ° C. for 20 seconds, and simultaneously the air is formed. Air was injected into the bag, and the sheet compact was adhered to the porous compact while pressing it.

[Experimental Example 2] Using the same porous molded body, acrylic emulsion adhesive and polyvinyl chloride sheet as in Experimental Example 1, according to the process shown in FIG. Was obtained.

[0029]

According to the present invention, a laminate of a low-density molded body and a heat-softening sheet useful as a sound insulating material, a sound absorbing material, a cushion material, etc., has uniform physical properties as a whole, , And can be produced industrially advantageously.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating an embodiment of the present invention.
(A) is a state where a vacuum forming die is arranged above the lower die,
(B) shows a state in which a low-density molded body is placed on a lower mold and a heat-softening sheet is arranged below the vacuum mold, (C).
FIG. 3 is a cross-sectional view showing a state in which a low-density molded body and a thermally softened sheet molded body are bonded to each other.

FIG. 2 is a schematic sectional view illustrating another embodiment of the present invention.
(A), (B), and (C) correspond to FIGS.
It is sectional drawing same as (B) and (C).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower mold 3 Airbag 4 Cushion body 5 Low-density molded object 6 Vacuum molding die 11 Heat-softening sheet 12 Adhesive 14 Coil spring

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 65/00-65/82 B29C 51/10

Claims (3)

(57) [Claims] 1. A method for producing a laminate comprising bonding and laminating a heat-softening sheet molded article on a low-density molded article, placing the low-density molded article in a cavity of a lower mold, An adhesive or pressure-sensitive adhesive is applied to the upper surface of the molded body, while the lower surface of the vacuum forming mold having a suction hole which is engaged with the upper surface of the low-density molded body and communicates with the internal hollow portion is formed on the lower surface by heat-softening. A sheet is supplied, heated and, at the same time, the heat-softening sheet is sucked through the suction hole by vacuum suction of the inner hollow portion of the vacuum forming die, and the sheet is placed on the lower surface of the vacuum forming die. A method for producing a laminate, comprising: forming a sheet into a corresponding shape; and then pressing and bonding the heat-softening sheet formed body to the upper surface of the low-density formed body. 2. In producing a laminate formed by bonding and laminating a heat-softening sheet molded article on a low-density molded article, the low-density molded article can be elastically deformed against a pressing force from above. Placed in the cavity of the lower mold with a perfect cushion body,
An adhesive or a pressure-sensitive adhesive is applied to the upper surface of the low-density molded body, and a heat-softening sheet molded body formed into a shape engaging with the upper surface is pressed and adhered to the upper surface of the low-density molded body. A method for manufacturing a laminate. 3. In producing a laminate formed by bonding and laminating a heat-softening sheet molded article on a low-density molded article, the low-density molded article can be elastically deformed against a pressing force from above. Placed in the cavity of the lower mold with a perfect cushion body,
While applying an adhesive or pressure-sensitive adhesive to the upper surface of the low-density molded body, the lower surface of the vacuum molding die having a lower surface formed with a suction hole that engages with the upper surface of the low-density molded body and communicates with the internal hollow portion is formed on the lower surface. Supply a heat-softening sheet and heat it,
The heat softening sheet is sucked through the suction hole by vacuum suction of the inner hollow portion of the vacuum forming die, and the sheet is formed into a shape corresponding to the lower surface of the vacuum forming die. A method for producing a laminate, comprising pressing and bonding this thermosoftening sheet molded article to the upper surface of the molded article.