JP2001353834A - Method for manufacturing laminated structure and laminated structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an inexpensive and lightweight laminated structure keeping bonding strength high and reduced in the amount of a thermosetting resin. SOLUTION: A PE film 2', an epoxy resin 3' and a glass fiber mat 4' are laminated on the surface of a core material 1 comprising a porous material in this order and hot-pressed at a predetermined temperature or higher. At first, the PE film 2' is melted to delay the impregnation of the core material 1 with the epoxy resin 3' and the impregnation amount in the core material 1 is reduced and the use amount of the epoxy resin 3' is can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated structure useful as a base material for an interior material of an automobile and a method for producing the same.

[0002]

2. Description of the Related Art A sandwich structure in which a porous material such as a paper honeycomb body or urethane foam is used as a core material as an interior material such as a sunshade or a moon roof door of an automobile, and a fiber reinforcing layer is bonded to both surfaces thereof. Substrates are known. Then, a skin made of PVC or the like is further laminated on the surface of the base material to form an automobile interior material.

[0003] The laminated structure such as the base material of the interior material is
Light weight due to the use of a porous body. Further, since it can be easily formed into a predetermined shape by hot pressing, mass production is possible and the cost can be reduced.

That is, to manufacture such a laminated structure, a plate-shaped core material formed in advance is prepared, and a thermosetting resin plate such as a phenol resin or an epoxy resin is laminated on both surfaces of the core material. Further, a plate-like fiber assembly formed of glass fiber or the like is laminated on the surface of the thermosetting resin plate. Then, when hot pressing is performed, the thermosetting resin plate becomes liquid and is impregnated into both the fiber assembly and the core material, and is thermoset in that state to integrally join the fiber assembly and the core material. Then, the laminate is shaped into a predetermined shape by hot pressing, and a sandwich-like laminated structure is formed.

[0005] In the obtained laminated structure, a thermosetting resin layer is formed between the fiber assembly and the core material, and the thermosetting resin layer impregnates the fiber assembly and the core material and cures. Both are integrally joined. In addition, the shape formed into a predetermined shape is retained by the thermosetting resin layer,
The rigidity of the laminated structure is ensured.

[0006] In a separate step, if the skin material formed into a predetermined shape by vacuum molding or the like is joined to the surface of the laminated structure obtained above, an interior material having a predetermined shape can be manufactured.

Japanese Patent Application Laid-Open No. 63-212136 also discloses a similar laminated structure.

[0008]

However, the thermosetting resin once becomes liquid by heating, and then the reaction proceeds to be cured. Therefore, in the above-described method for manufacturing a laminated structure, the thermosetting resin that has become liquid during hot pressing impregnates deep inside the core material. The thermosetting resin impregnated deep inside the core material does not contribute to the bonding between the fiber assembly and the core material at all. On the other hand, if the amount of the thermosetting resin is reduced, the bonding strength between the fiber assembly and the core material becomes insufficient, so that an excessive thermosetting resin is necessary more than necessary, and the interior material base material is accordingly reduced. The cost was high. Also, the weight increases due to the excess thermosetting resin.

The present invention has been made in view of such circumstances, and has as its object to reduce the amount of thermosetting resin while maintaining a high bonding strength, and to provide an inexpensive and lightweight laminated structure. .

[0010]

The feature of the method for manufacturing a laminated structure according to the present invention that solves the above-mentioned problems is that a thermoplastic resin film and a thermoplastic resin are provided on the surface of a plate-shaped core member made of a porous material. An adhesive resin that cures or softens at a predetermined temperature higher than the melting point of the film, and a fiber assembly are laminated in this order, and then heated and pressed at a predetermined temperature or higher to melt the thermoplastic resin film and to integrate the fiber with the adhesive resin. It is to join a body and a core material integrally.

The laminated structure of the present invention manufactured by the above manufacturing method is characterized by a plate-shaped core layer made of a porous material, an adhesive resin layer formed on at least one surface of the core layer, and an adhesive layer. In a laminated structure composed of a fiber reinforcing layer integrally joined to a core layer by a resin layer, a laminated structure has a thermoplastic resin layer between the core layer and the adhesive resin layer.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method for producing a laminated structure according to the present invention, a thermoplastic resin film is provided on a surface of a plate-shaped core material.
The adhesive resin and the fiber assembly are laminated in this order, and then heated and pressed at a predetermined temperature or higher, which is higher than the melting point of the thermoplastic resin film, to melt the thermoplastic resin film and to bond the fiber assembly and the core material with the adhesive resin. And are integrally joined.

At the time of heating and pressing, the thermoplastic resin film is first melted and impregnated into the core material. Therefore, the impregnation of the core material with the liquid adhesive resin is suppressed by the thermoplastic resin impregnated in the core material. Is done. Also, if the heating and pressing time is the same as in the past, the time required for the adhesive resin to impregnate the core material is delayed due to the presence of the thermoplastic resin, and the time required for the impregnation is substantially reduced. Impregnation into the core material is suppressed.

Therefore, the amount of the adhesive resin interposed between the fiber assembly and the core material without impregnating the core material increases, and the same bonding strength as before can be secured even if the amount of the adhesive resin used is reduced. Becomes possible. And since thermoplastic resin is much cheaper than adhesive resin such as thermosetting resin, even if the raw material cost increases by the amount of thermoplastic resin film,
Overall, it can be significantly cheaper. Further, since the weight of the adhesive resin which is reduced as compared with the weight of the thermoplastic resin film to be used is larger, the weight can be reduced accordingly.

As the core material, a plate-like porous body formed of a paper honeycomb body, a urethane foam, a polymer foam, or the like is used, and the same material as in the related art can be used. In the case of a honeycomb body, the core material is formed such that the honeycomb passage extends in the thickness direction.

As the thermoplastic resin film, polyethylene, polypropylene, polystyrene, nylon, PV
Those formed from thermoplastic resins such as C, vinyl acetate, AS resin, polyester resin, acrylic resin, and thermoplastic elastomer can be used. This thermoplastic resin film has a content of 20 to 100 g /
It is preferable to use a thickness of m ² . If the amount of the thermoplastic resin film is less than this range, the effect of the interposition cannot be obtained. If the amount is more than this range, the effect is saturated, the cost and weight increase, and the bonding strength may decrease. It is necessary to use a thermoplastic resin film having a melting point lower than the temperature at which the adhesive resin hardens or softens.

The adhesive resin may be a thermosetting resin such as a phenol resin or an epoxy resin, a hot melt adhesive, or the like. The fiber assembly and the core material can be joined by heating and pressing, and the laminated structure is formed into a predetermined shape. What can hold | maintain in the state shape | molded to is used. A thermosetting resin that can provide a certain degree of rigidity after curing or solidification is desirable. Alternatively, a thermosetting foamed resin that foams and cures can be used.

The shape of the adhesive resin before bonding may be any shape as long as it can be arranged on the thermoplastic resin film, and may be in the form of a sheet, a plate, a powder, or in some cases a liquid. In the case of a thermosetting resin, it goes without saying that a curing agent for curing by heating is included. In the case of a thermosetting resin, its curing temperature needs to be higher than the melting point of the thermoplastic resin film. In the case of a hot melt adhesive, it is necessary that the melting point be lower than the melting point of the thermoplastic resin film. And after the hot melt adhesive is sufficiently melted, the thermoplastic resin film melts,
It is desirable that the hot melt adhesive is configured to flow slightly to the core material side.

In any case, it is desirable that the curing temperature or melting point of the adhesive resin is higher than the melting point of the thermoplastic resin film by about 50 ° C. or more. When this temperature difference is smaller than about 50 ° C., the time difference between the melting of the thermoplastic resin film and the impregnation of the adhesive resin into the core material becomes small, and the adhesive resin is impregnated deep into the core material.

The amount of the adhesive resin to be used varies depending on the type of the resin, but is generally 50 to 500 g / g to the surface of the core material.
It is preferable to use m ² . If the amount of the adhesive resin is less than this range, the bonding strength or shape retention between the fiber assembly and the core material is reduced, and if it is more than this range, the bonding strength is saturated and the cost and weight increase.

Examples of the fiber aggregate include woven fabrics, nonwoven fabrics, knitted fabrics, mats, and paper made of short fibers or long fibers of various fibers such as organic fibers, inorganic fibers, and metal fibers. The amount of the fiber aggregate varies depending on the fiber type, apparent density, and the like, but it is generally preferable that the fiber aggregate be used in an amount of 50 to 500 g / m ² relative to the surface of the core material.

In the manufacturing method of the present invention, a thermoplastic resin film is disposed on the surface of the core material, an adhesive resin is disposed thereon, and a fiber assembly is further disposed thereon. The laminate may be laminated only on one surface of the core material, or may be laminated on both surfaces. Then, it is clamped by a predetermined mold and heated and pressed at a predetermined temperature. The predetermined temperature is a temperature at which the thermoplastic resin film melts and the adhesive resin cures or melts. Various pressures can be selected depending on the case.

The thermoplastic resin film is melted by heating and pressing, and pores of the core material are exposed, into which the liquid adhesive resin is impregnated. The liquid adhesive resin also impregnates the fiber assembly. The melting and impregnation of the thermoplastic resin film delays the impregnation of the adhesive resin into the core material, and also reduces the amount of impregnation into the core material. By controlling the mold temperature and the hot pressing time, the impregnation amount of the adhesive resin can be controlled.
Then, by solidifying the adhesive resin, the fiber assembly and the core material are integrally joined to form a laminated structure shaped into a predetermined shape.

Therefore, according to the manufacturing method of the present invention, it is possible to secure the same bonding strength as before with a smaller amount of adhesive resin than before, and to manufacture a low-cost and lightweight laminated structure.

[0025]

The present invention will be described below in detail with reference to examples.

FIG. 1 is a schematic sectional view of a base material of an automobile interior material manufactured by the manufacturing method of this embodiment. The base material includes a honeycomb core material 1 made of paper, a thermoplastic resin layer 2 laminated on both surfaces of the core material 1 and partially impregnated into pores of the core material 1, and a thermoplastic resin layer 2. Epoxy resin layer 3 laminated on the surface and partially impregnated into pores of core material 1 and cured
And a fiber reinforcing layer 4 made of a glass fiber mat laminated on the surface of the epoxy resin layer 3 and partially impregnated and cured.

In the actual cross section, the thermoplastic resin layer 2
Has a plurality of openings corresponding to the honeycomb passage of the core material,
A part is impregnated in the core material 1. Also, most of the epoxy resin layer 3 is impregnated in the core material 1 and the fiber reinforcement layer 4, so that the boundary is not clear as shown in FIG.

Hereinafter, the method for producing the base material will be described with reference to FIGS. 2 to 4, and the detailed description of the structure will be substituted.

First, a honeycomb-shaped core material 1 made of paper separately formed in advance is prepared. The core material 1 has a honeycomb shape in which a honeycomb passage having a square cross section and a side of about 5 mm is arranged in a grid pattern, and a thickness direction of the honeycomb passage extends in a thickness direction of about 5 mm.

Next, polyethylene (P) having a thickness of about 50 μm
E) A film 2 ′ is prepared and placed on both surfaces of the core material 1. The amount of PE is 50 g with respect to the surface of the core material 1.
/ M ² .

Further, on the surface of the PE film 2 ',
Phenol epoxy resin 3 'and glass fiber mat 4'
Are laminated in this order. Phenol epoxy resin 3 'is powder
Glass fiber mat consisting of short glass fibers
4 'in a layered manner. FIG. 2 schematically
Separately from the glass fiber mat 4 '. this
The phenol epoxy resin 3 ′ is applied to the surface of the core material 1.
500g / m on both sides ^Two And the amount of Also glass
The fiber mat 4 ′ is 50 on both sides with respect to the surface of the core material 1.
0 g / m^Two And the thickness of the material.

As shown in FIG. 3, the laminate 10 is placed in a mold 5 of a predetermined shape which is temperature-controlled by oil, and as shown in FIG.
Hot press molding was performed at a pressure of 0 kg / cm ² for 60 seconds. Thereafter, the mold was opened, and a substrate having a cross-sectional structure shown in FIG. 1 was obtained.

The obtained base material for the interior material is shaped into the mold surface shape of the mold 5, and the core material 1 and the fiber reinforcing layer 4 are impregnated with a part of the epoxy resin layer 3 and cured. While maintaining its shape, the core material 1 and the fiber reinforcement layer 4 are integrally and firmly joined. The rigidity is mainly ensured by the epoxy resin layer 3.

Then, the thermoplastic resin film 2 'is interposed
Not the conventional manufacturing method, phenol epoxy
The amount of the resin 3 ′ is 600 g on both sides with respect to the surface of the core material 1.
/ M ^Two If the above conditions are not met, is it possible to secure the required bonding strength
However, in the present embodiment, 5
00g / m^Two The required adhesive strength can be secured with the amount of
The amount of the epoxy resin 3 ′ is 1 to the surface of the core material 1.
00g / m^Two Could be reduced. Therefore this implementation
According to the example manufacturing method, is it cheaper than the conventional manufacturing method?
One lightweight substrate could be manufactured.

[0035]

According to the manufacturing method of the present invention, the same bonding strength as that of the related art can be secured with a smaller amount of the adhesive resin, and a low-cost and lightweight laminated structure can be manufactured.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a laminated structure obtained by a manufacturing method according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a laminated structure of each layer in the manufacturing method according to one embodiment of the present invention.

FIG. 3 is an explanatory cross-sectional view showing a state in which a laminate is disposed in a mold in the manufacturing method according to one embodiment of the present invention.

FIG. 4 is an explanatory cross-sectional view showing a state where a laminate is hot-pressed in a mold in the manufacturing method according to one embodiment of the present invention.

[Explanation of symbols]

1: core material 2: thermoplastic resin layer
2 ': PE film 3: Epoxy resin layer 3': Phenol epoxy resin
4: Fiber reinforcement layer 4 ': Glass fiber mat 5: Mold

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuo Ishiguro 2-10-10, Amisumi-Shirayama-cho, Kasugai-shi, Aichi F-term in Howa Textile Industry Co., Ltd. 4F100 AG00C AK01B AK01C AK01E AK01E AK04B AK04E AK33B AK33E AK53B AK53E BA05 BA06 BA10D BA26C BA26E DG06D DG06E DJ01A EC032 EC051 EC182 EJ172 EJ422 GB33 JA04B JA04C JA04E JB16B JB16E JK06 JL02 JL11C JL11E

Claims (2)

[Claims] 1. A thermoplastic resin film, an adhesive resin that cures or softens at a predetermined temperature higher than the melting point of the thermoplastic resin film, and a fiber assembly on a surface of a plate-shaped core material made of a porous material. In this order, the thermoplastic resin film is melted by heating and pressing at a temperature equal to or higher than the predetermined temperature, and the fiber assembly and the core material are integrally joined with the adhesive resin. A method for manufacturing a laminated structure. 2. A plate-shaped core layer made of a porous body, an adhesive resin layer formed on at least one surface of the core layer, and fibers integrally joined to the core layer by the adhesive resin layer. A laminated structure comprising a reinforcing layer, wherein the laminated structure has a thermoplastic resin layer between the core layer and the adhesive resin layer.