JPS58102754A - Laminated shape and its molding method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laminate molded product having a core made of a fiber-reinforced thermoplastic resin sheet and a method for molding the same.

The fiber-reinforced thermoplastic resin sheet referred to in the present invention is a sheet made of glass fiber or the like as a reinforcing material and a thermoplastic SR resin as a matrix. In particular, the reinforcing material made of mat-like relatively long fibers is impregnated with a thermoplastic resin matrix. This is what I did.

Then, the sheet is trim-cut according to the size of the molded product to be obtained (the cut material before molding is hereinafter referred to as a blank), and then heated and softened in a heating furnace to a temperature higher than the softening temperature of the matrix resin (hereinafter, heated (referred to as a blank), then press-molding the heated blank in a matte metal die maintained at a temperature below the softening temperature of the matrix resin,
By solidifying it, it can be molded into a molded article with a desired curved surface shape.

According to this method, it is possible to press mold a thermoplastic resin containing a relatively long fiber reinforcement into a large size, and the time required for molding is also short. Furthermore, the molded product thus obtained exhibits excellent physical properties in addition to the reinforcing effect of the long fiber reinforcement, and is attracting attention as a lightweight structural material to replace steel.

However, a disadvantage of the seed molded product is that the reinforcing fibers protrude on the surface of the molded product, resulting in poor appearance.

Therefore, forming another decorative surface by laminating it on the surface of the molded product is extremely effective for the molded product made of the seed fiber-reinforced thermoplastic resin sheet.

To achieve this purpose, when placing a heated blank on the mold surface of a matted metal die during press forming,
The decorative surface can be applied to the surface of the molded product by overlaying a sheet with a decorative surface on top of the sheet (hereinafter referred to as an overlay sheet), and simultaneously bonding and integrating the two sheets. If you can attach it,
This is an economically extremely advantageous method (hereinafter this molding method will be referred to as overlay molding).

Therefore, in order to form a fibrous decorative surface on the surface of a press-molded product made of reinforced thermoplastic resin, we attempted overlay molding of a fibrous material. It was found that the material was so severely damaged that it was not possible to obtain the desired decorative surface.

This is because the molten resin in the heated blank penetrates into the fibrous structure due to the pressure during pressing, and further oozes out to the surface, causing the decorative effect of the fibrous surface to be lost.

The present invention is based on fiber ag! As a result of various studies on overlay molding methods to maintain a good decorative surface of i. We have discovered that the above objectives can be achieved by stacking and press-molding an integrated sheet of fiber-reinforced thermoplastic resin whose porous layer has been softened by heating so that it is in contact with the surface of the sheet. This led to the completion of the present invention.

Examples of reinforcing fibers in the reinforced thermoplastic resin sheet used in the present invention include glass fibers, carbon fibers, and amide fibers.

Thermoplastic resins that are matrix resins include industrial materials such as polyethylene, polypropylene, poly(vinyl oxide, polymethyl methacrylate), ABS resin, polyamide resin, polyethylene terephthalate, polybutylene terephthalate, l-licarbonate, and polyacetal. These thermoplastic resins are blended in appropriate proportions with the above-mentioned fiber-reinforced material formed in the form of mat, cloth, yarn, etc., and provided as an integrated flat fiber-reinforced thermoplastic resin sheet.

Next, the breathable decorative skin material with a decorative surface used in the present invention includes woven fabrics and raised hem fabrics made of various natural and/or synthetic fibers.

Examples include knitted fabrics such as knitted fabrics, flocked fabrics, and carpets such as needle punch carpets and tufted carpets. Further, the closed cell foam, that is, the non-air permeable porous layer laminated thereon, is polyethylene or polypropylene.

A flexible material that is easily deformed, such as a foam such as polyvinyl chloride, is preferred, and the foaming ratio is 2 to 2.
It is preferable to have a thickness of about 50 times and a thickness of about 0.1 to 5+lII+. It is also possible to use a plastic film laminated to one of the closed cell foams.

These foams are then firmly laminated to the back side of the sheet having the fibrous decorative surface using an adhesive or the like, and this laminated sheet is used as an overlay sheet.

Next, a molding method using the blank <m-fiber-reinforced thermoplastic resin> constructed as above and the over Louis sheet will be described with reference to the drawings.

First, the blank 1 is trimmed to approximately match the shape of the desired molded product, and then, as shown in FIG. 1, it is placed in an infrared heating furnace 3 and its top and bottom surfaces are heated. Due to this heating)
The temperature is raised above the melting temperature of the resin constituting the matrix, resulting in a softened heated blank 1/. As the matrix resin melts, this heated blank 1' becomes unable to suppress the repulsive force of the fibers that are its reinforcing material, and as a result expands (swells) in the thickness direction, its bulk increases and it contains a large amount of air. It turns out.

This heating blank 1/ is placed on the mold surface 4a of the lower mold 4 of the mated metal die as shown in FIG. The heating blanks 2b and 2b are stacked in contact with the heating blank 1', and then the upper mold 6 is immediately lowered to perform press molding.

During press molding, the reinforcing material fibers and molten resin constituting the softened heated blank 1' flow through the cavity formed in the mold as the upper mold 6 descends and the mold is closed. On the side in contact with the overlay sheet 2, the pressing pressure is applied to the heated blank through the overlay sheet 2 and flows along the surface of the closed cell foam layer 2b of the overlay sheet 2.

Figure 3 shows the mold in a closed state, and there is a shear edge between the upper and lower molds 4 and 6 at the periphery.
Although air is discharged, a small clearance d is provided to prevent the resin from flowing out as much as possible.

In the final stage of the above molding process, the cavity inside the mated metal die is completely filled with the heating blank 1' and the overlay sheet 2, and is closed leaving the above-mentioned shear edge clearance d.
~15011: A pressure of V- is applied, thereby almost completing defoaming.

Furthermore, since the mold 4.5 is maintained at a temperature lower than the softening temperature of the matrix resin, the matrix resin is cooled and solidified inside the mold. Therefore, if the upper mold 6 is separated from the upper mold 6 after cooling and heating is sufficient, and the molded product is demolded, an overlay molded product having the desired curved surface shape in which the blank 1 and the overlay sheet 2 are integrated can be obtained.

The function of the closed-cell foam layer provided as an intermediate layer in the above overlay molding process is that the molten thermoplastic resin in the heated blank is forced into the internal voids of the vA fiber PA weave by the pressure during press molding. prevent it from penetrating. Secondly, the texture of the fibrous surface decoration layer is protected by the insulation effect against the heat from the heated blank and the line drawing effect against the press pressure. For example, in the case where the fibrous material has a raised surface, it is possible to prevent the hair from falling down due to press pressure, and to prevent permanent deformation due to heat when the hair falls down. Third, when the molten resin in the heated blank softens and destroys a portion of the foamed skin of the closed-cell foam and penetrates into the foamed cells of the surface layer, the thermoplastic resin cools and solidifies. A strong bond is created between the layer of closed cell foam and the reinforced thermoplastic resin layer due to physical interleaving effects.

Note that the closed cell foam layer has no air permeability, but when the heated blank is press-molded, the air bubbles between the closed cell foam layer and the heated blank are dispersed on the surface of the foam layer and directed toward the periphery of the mold. The gas is removed and degassed effectively.

In addition, if this effect is not sufficient, try using hot water in the heated blank! By drilling small pores at an appropriate density over the entire surface of the closed-cell foam layer to prevent the resin from seeping out when pressed, but allowing air to pass through, the air on the heated blank side can be removed. It can also be allowed to escape to the surface fiber layer side through small holes.

Therefore, as mentioned above, the overlay molded article obtained by the present invention, Atsu-C, has a good appearance of the air permeable decorative skin on its surface, and also has a strong bonding force with the blank, and has a good bonding strength with the blank. The non-breathable porous layer also has a cushioning effect, so it can be used as a structural material for parts that require strength and decorative appearance, such as exterior and interior materials for automobiles, casing parts for home appliances, etc. It can be applied to a wide range of applications such as furniture and furnishings.

Next, further specific examples of the present invention will be described.6However, the present invention is not limited to the following examples.

Practical example 1゜40% by weight of matte glass integrated reinforcement material, matrix t
The QW is a reinforced thermoplastic resin sheet made of 60% polypropylene (trade name Aztyll, manufactured by PPG) with a thickness of a7W and a unit weight of 4.3 Kg/d, which is 160WX.
Two blanks cut to a size of 300 wes were used.

A heated blank was obtained by heating the blank until the internal resin temperature reached 2oo<0>C. The press molding was carried out using a mated metal die as shown in FIG. 3 to obtain a box-shaped product. Approximate dimensions of the box are 190LX390WX40H
, thickness 41. The outer surface of the hooker portion is R7, the inner surface R3, and the draft angle is 1° on the outer surface and 5° on the inner surface. Figure 3 shows the mold in a closed state, and its periphery has a shear edge as shown by the symbol d, and the shear edge clearance between the lower matted metal and the upper die is set to 0.6 blinds. ing.

On the other hand, the overlay sheet is made of brushed woven fabric made by Kaneka Fyo Co., Ltd. (unit weight 244F/#/*thickness L41M) as a decorative surface layer.
was used. Also, as a closed-cell foam, the apparent thickness is Qw.
, using a foamed polyethylene sheet with a foaming ratio of 35 times.
Both are laminated in advance using synthetic rubber latex as an adhesive. This was then placed over the heating blank, and the upper die was immediately lowered. (overlace) was molded to cover the outer surface of the box as the linear die descends.

Next, as shown in FIG. 3, with the mold closed leaving a small shear edge clearance at the periphery, a pressure of 100 m was applied and held for 20 seconds, and the opening temperature was maintained at aO<0>C. In this state, defoaming through the air edge clearance was completed and the heating blank and overlay sheet were in close contact.

Next, the mold was pulled up and the molded article was demolded. Observation of this product shows that the molten plastic pyrene in the heated blank is prevented from penetrating into the raised woven fabric layer by the foamed polyethylene sheet, and the texture of the decorative surface of the raised hem fabric layer is maintained well. ).

In addition, an overlay molded product that was firmly bonded to the base layer could be obtained. By the way, the peel strength between the two is α6 Kv'
The measurement results showed that the molded product had relatively high strength compared to CD.

Comparative example 1゜Example 1. Overlay molding was carried out in the same process using the raised woven fabric manufactured by Kaneka Tan as the overlay sheet. In this case, the molten polypropylene in the heated blank penetrates into the structure of the raised woven fabric during press molding and seeps out to the surface, causing significant damage to the fiber structure, resulting in a complete loss of the decorative effect on the surface. Ta.

Example λ Overlay molding was performed in the same manner as in Example except that the overlay sheet was replaced with the following one.

Overlay sheet: A double-foamed polyethylene sheet with a thickness of 0.6 was laminated on the back side of a polypropylene fiber needle punch carpet (manufactured by Dynic, unit weight: 420 F, Otsu-) via synthetic rubber latex.

In the case of this example, a needle-punched decorative surface is formed on the inner surface of the box-shaped molded body, and the overlay sheet is placed along the lower die so that the surface of the needle-punch carpet is in contact with the lower matte metal. Overlapping portions at the four corners of the overlay sheet were cut out in advance so that it could be covered and molded along the outer surface of the lower mold.

Next, two heated blanks were placed on top of each other, and the upper mold was immediately lowered to perform molding.

When the product in this case was observed, a box was obtained in which the needle punch carpet was firmly attached to the inner surface of the molded box without any damage. Incidentally, the peel strength between the overlay and the base layer was α5Kg/rrl.

Comparative Example 2 In Example 2, the needle punch carpet was used as an overlay sheet and molded in the same manner as in Example 2.

However, in this case, the softened and melted polypyrene penetrates into the carpet tissue and even penetrates to the surface.
The desired beautiful appearance was completely lost.

[Brief explanation of drawings]

Figures 1 to 3 are for explaining the details of this invention. Figure 1 is an explanatory diagram showing the heating process of the blank, and Figure 2 is a diagram showing the blank and overlay sheet set on a press molding hot water. FIG. 3 is a cross-sectional view showing the press molding die in a secured state. 1-Blank (fiber-reinforced thermoplastic resin sheet) 1'-Heating blank 2-Overlay sheet 2a-Decorative skin 2b-Closed cell layer (non-breathable porous layer) 3-Heating furnace Imaichi lower mold 4m - Mold surface 6 - Upper mold 5m - 1 mold surface Patent applicant Ube Nitto Kasei Co., Ltd. agent Patent attorney - Ken Iro Axle box 1 Figure 2 Figure 2 265 Figure 3

Claims (2)

[Claims] (1) A core made of a fiber-reinforced thermoplastic resin sheet molded into the desired shape, one side of which is heat fused to the outer surface of the core, and a breathable decorative skin formed on the surface. A laminated molded product made of non-breathable porous sheets. (2) A molded article of a desired shape is formed by placing a heat-softened fiber-reinforced thermoplastic resin sheet on one mold surface of a press molding die and applying pressure to the other mold. In this step, a non-breathable porous layer is laminated on the back side of an air-permeable decorative skin having a decorative surface, and is integrated with the decorative skin, and the integrated sheet is laminated with the porous layer on one mold surface. A method for molding a laminate molded article, in which the installed fiber-reinforced thermoplastic resin sheets are stacked so as to be in contact with the surface, and then the other mold is held and pressurized.