JPS58102753A - 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 one in which glass fiber or the like is used as a reinforcing material and a thermoplastic resin is used as a matrix. IJ'FW Ma) Impregnated with IJ Lux.

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 bale blank), and then heated and softened in a heating furnace to a temperature higher than the softening temperature of the matrix resin (hereinafter referred to as (referred to as a heated 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 due to the reinforcing effect of the long fiber reinforcement, and is attracting attention as an AT 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 is applied to the surface of the molded product by stacking a sheet with a decorative surface on top of it (several sheets are hereinafter referred to as overlay sheets), shaping it with a press, and simultaneously joining and integrating the two sheets. If possible,
This is an economically extremely advantageous method (hereinafter this molding method will be referred to as overlay molding).

However, when we tried overlay molding using a non-air permeable, smooth-surfaced sheet with its smooth surface in contact with a heated blank, we found that there was a close contact between the blank-shaped molded product and the overlay sheet. It was found that there were parts that were not bonded, and even if there were parts that were in close contact, there was no bonding force and they were easily peeled off.

The reason for this is that the reinforcing fibers expand when the blank is heated and contain air inside, but if pressure is applied in this state, the air between the heated blank and the overlay sheet cannot be degassed sufficiently. , remains between the two. In addition, regarding the bonding force between the two, the thermoplastic resin component in the heated blank flows through the press, is shaped, and solidifies while in contact with the smooth surface of the overlay sheet, so there is a special bond between the two. It cannot be expected that strong bonding force will be generated.

The present invention was developed as a result of various studies on an overlay molding method that firmly connects and integrates an overlay sheet and a molded body without leaving any air bubbles between them. A breathable porous layer is placed on the back surface and integrated with the decorative skin, and the integrated sheet is placed in such a way that the breathable porous layer is in contact with the surface of the heat-softened fiber-reinforced thermoplastic resin sheet. The inventors have discovered that the above objects can be achieved by overlapping and press-molding, and have thus completed 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.

In addition, thermoplastic resins that are matrix resins include polyethylene, polypropylene, polyvinyl chloride, polymethyl methacrylate), ABC resin, polyamide resin,
Examples include industrial materials such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and boria heptatal.
It is blended in an appropriate proportion with the fiber reinforced material formed in the form of yarn or the like, and provided as an integrated flat fiber reinforced thermoplastic resin sheet.

Next, the non-breathable decorative skin used in the present invention may have a smooth surface, or may have various textures such as cloth, leather fas, or simulated leather, or may be a processed plastic sheet (or film) or metal foil. , a plastic sheet (or film) subjected to metal vapor deposition, and the like.

Another example is woven fabric, I! Examples include materials that have a fibrous surface such as cloth, nonwoven fabric, flocked fabric, etc., and are breathable, but have lost their breathability due to backing up a film or coating on the back side.

Examples of the porous layer used in the present invention include open-cell plastics such as polyurethane foam, woven fabrics (knitted fabrics) made of various fiber materials, non-woven fabrics or glass fibers (pine), or fibrous materials such as paper. In order to laminate this layer to the back side of the above-mentioned decorative skin, it is necessary to bond the two with an adhesive, or to laminate the breathable porous layer to the back side of the above-mentioned decorative skin. If it is a thermoplastic, it can be bonded by heat fusion.

Next, a molding method using the blank fiber-reinforced thermoplastic resin and overlace (breathable porous sheet) constructed as above will be described with reference to the drawings.

First, the blank 1 is trim-cut to roughly match the shape of the desired molded product, and then, as shown in Figure 1, it is placed in an infrared heating furnace 3, where it is heated from the top and bottom to a temperature above the melting temperature of the resin constituting the matrix. The heated blank 1' is heated to a temperature of 1, and becomes a softened heated blank 1'. As the matrix resin melts, the heated blank 1' becomes unable to suppress the repulsive force of the reinforcing fibers, and as a result of expanding in the thickness direction, it contains a large amount of air.

This heating blank 1' is placed on the mold surface 4 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.

The reinforcing material fibers and molten resin constituting the softened heated blank flow in the cavity formed in the mold during press molding, when the upper mold 6 descends and the space between the two molds 4 and 5 is closed. However, on the side in contact with the overlay sheet 2, the press pressure is applied to the heated blank 1' through the overlay sheet 2, and flows along the air permeable porous surface of the overlay sheet 2. Then, the air in the heating blank 1/ is exhausted toward the mold surfaces 4a, 5m of the mold surfaces 4.6 of both the molds 4.6 as the upper mold 6 descends and press molding progresses.

Figure 3 shows the same mold in a closed state, and the upper and lower molds 4 and 15 at the periphery are shear edges, and air is exhausted, but in order to prevent the resin from flowing out as much as possible, it is made very small. The air permeable porous layer 2b has the function of dispersing and passing air bubbles in the above-mentioned defoaming process, and therefore, the air bubbles are dispersed and passed through the porous layer 2b in this way. The defoamed air is discharged outside the mold through the clearance d.

In addition, in the case of overlacing F without the porous layer 2b, it is difficult for all the air contained in the heating blank to be degassed from the above-mentioned clearance.
As a result of local accumulation between the overlay sheet and the heated blank, unevenness occurs and the appearance of the product is significantly impaired.

Another function of the porous layer 2b is to strongly bond the overlace (2) to the surface of the molded product. That is, through the above-mentioned press forming process, the cavity inside the mated metal die is completely filled with the heated blank and overlay sheet and closed, leaving a shear edge clearer, and the inside of the mold is filled with 100 to 160 g/l. pressure is applied. As a result, defoaming is almost completed, and the molten resin permeates into the air-permeable porous layer of the overlay sheet. Since the mold 4.6 is kept at a lower temperature than the softened mixed carbon of the matrix resin, the matrix resin is cooled and solidified inside the mold, but the resin that has penetrated into the porous layer solidifies in this state. , a strong bond can be created between the porous layer and the reinforced thermoplastic layer.

This bonding can also be thought of as a physical anchoring effect that acts on the large contact surface area created by the fibers or open-cell foam constituting the porous layer being embedded in the matrix resin.

On the other hand, in the case of an overlay sheet that does not have a porous layer, even if the overlay sheet is in close contact with the surface of the molded product, there is a flat surface between them, so no such bonding force occurs. As a result, it becomes easy to peel off.

Therefore, in the overlay molded product obtained by the present invention, a smooth surface can be obtained without leaving any air bubbles on the surface as described above, and the bonding force with the plank is also large, and the overlay molded product is Because the breathable porous layer also has a cushioning effect, this material can be used as a structural material for parts that require strength and appearance, such as exterior and interior materials for automobiles, casing parts for home appliances, etc.
It is widely used in furniture, furnishings, and industrial parts that require a metal layer on the surface.

Next, specific examples of the present invention will be described.

However, the present invention is not limited to the following examples.

Example 1 Reinforced thermoplastic resin sheet (trade name: Azdel, manufactured by PPG) consisting of 40% by weight of matte glass fiber reinforcement and 60% by weight of Giripropylene as a matrix resin, with a thickness of a7sw7 and 4.3 Ky/rrl. 15 Qw
A blank 2 piece cut to the dimensions of x3 Q Q++w was used. A heated blank was obtained by heating the blank until the internal resin temperature reached 200°C. The blank contained air as the matrix polypropylene melted due to heating and expanded to about three times its original thickness due to the repulsive force of the reinforcing glass fiber mat. Press molding was carried out using a mated metal die as shown in FIG. 2 to obtain a box-shaped product.

Approximate dimensions of the box are 190L x 90 W x 40 H, thickness 4 electric, hooker part outer surface R7, inner surface R3, draft angle outer surface 1°,
The inner surface angle is 6°. FIG. 3 shows the state when the mold is closed, and the peripheral edge is a shear edge as shown by the symbol d, and the shear edge clearance between the lower die mated metal and the upper die is α5vaz.

An overlay sheet was prepared in which 0.2wI thick paper was adhered in advance to the back side of a 0.3M thick hard vinyl chloride sheet using synthetic rubber latex as an adhesive.

As shown in Fig. 2, two heated blanks 2 were stacked on top of the lower mated metal 4 of a press molding die, and an overlay sheet was placed over the heated blank so that the surface covered with kraft paper was in contact with the heated blank.

Heat the overlay sheet to 120℃30 in a hot air oven beforehand.
It was heated for about seconds to soften it.

The upper die was immediately lowered. The softened overlay sheet was squeezed as the upper die descended and was formed to cover the outer surface of the box. During the pressing process, the air contained in the heated blank is exhausted from the peripheral edge clearance, but at this time, the paper layer stretched on the back of the overlay sheet disperses the air and allows it to pass through the shear edge clearance. It served the purpose of escaping. As shown in FIG. 8, a pressure of 100 tons was applied and held for 20 seconds while the mold was closed leaving a small shear edge clearance at the periphery. The mold mixed coal was kept at 60°C. In this state, deaeration through the shear edge clearance was completed, the heating blank and the overlay sheet were brought into close contact, and the molten polypropylene was further solidified while penetrating into the tissue space of the paper layer on the back side of the overlay sheet. An overlay molded product was obtained in this way, and the peel strength between the overlay layer and the base layer was measured and the result was α5 Ky/an.
Met.

This strength corresponds to the force with which the navy blue cellulose fibers embedded in the base layer are torn off.

Comparative example 1゜Example 1. Thickness 06 as overlay sheet in
Overlay molding was performed in the same manner using a hard vinyl chloride sheet of No. 8 as it was.

The overlay sheet is molded and covers the surface of the molded product, but on the top surface of the molded box, air remains over a wide area between the overlay sheet and the base of the molded product, and this area is in contact with the molded product. I haven't. Also, the peel strength between the overlay layer and the base layer was 0 for the portions of the side surface of the box that were apparently in close contact with each other.

Example λ A glass fiber reinforced nylon resin sheet was prepared by the following method. Continuous strand mat (manufactured by Asahi Fiberglass) as glass tan-rut.

Unit weight: 5 oor/I/) E: A sheet of 05 thick nylon 6 was prepared as the resin. Knife sheet 1 from below
1 glass mat, 2 nylon sheets, 1 glass mat, and 1 nylon sheet, and put them between the hot plates of a heating press and heat them at 260℃ to melt the nylon 6. The glass fiber strand mat was sufficiently impregnated with molten nylon 6 by pressing to a thickness of about 100 ml, and then solidified in the cold to obtain a reinforced thermoplastic resin sheet. This sheet consists of 35% by weight glass fiber and 66% by weight nylon seam. As an overlay sheet, a foamed polyurethane sheet (expansion ratio: 30 times) having an apparent thickness of Im was stretched on the back side of a hard vinyl chloride sheet α8-thick having an aluminum vapor deposited layer (aooA) and synthetic rubber latex as an adhesive. Three blanks made by cutting reinforced nylon resin seeds into dimensions of 160W x 7300ss were prepared and heated in an infrared heating furnace until the internal resin temperature reached 240°C to obtain heated blanks.

Example! Geo-burley molding was performed in the same manner using the same mold as in . However, the mold temperature was maintained at 120°C.

During the press molding process, air passed through the foamed polyurethane layer and was completely degassed from the clearance at the shear edge, and the nylon resin entered the foamed polyurethane voids and solidified, strongly bonding to the foamed layer. As a result, an overlay molded product was obtained in which the hard vinyl chloride layer on the surface was firmly and closely bonded to the base layer via the foam layer. The peel strength between the overlay layer and the base layer was 0.6 F'4/an, which corresponds to the force with which the urethane breaks when foamed.

Example 3 Example 1. The overlay sheet was replaced with the following. A polyethylene terephthalate fiber nonwoven fabric (trade name: Spunlace Gentara 48000, manufactured by Toyo Pu! Daktsu, unit weight: 40 f/n?) was adhered to the back side of a 0.251111 thick aluminum foil using an epoxy adhesive.

This sheet was previously drawn and formed using a press so that it conformed to the outer surface of a box, which was a molded product. At this time, the surface on which the nonwoven fabric was stretched was made to be the inner surface.

Example 1. When performing overlay molding in a similar manner using the same mold as above, two heated blanks were placed on top of the lower mold, and on the other hand, the overlay sheet was drawn from the laminated sheet of aluminum foil and nonwoven fabric prepared earlier. Pressing was performed by lowering the upper die while it was inserted into the upper die.

The adhesive bond between the aluminum foil and the base layer was good, and no air bubbles remained. When the peel strength between the two was measured, it was 2.4 KV-, which corresponds to the strength that can tear the polyethylene terephthalate fibers that make up the entire nonwoven fabric.

Example 4゜Example 1. The overlay sheet was replaced with the following one. Synthetic rubber latex is applied to the back side of a polypropylene fiber needle punch carpet (manufactured by Dynic, unit weight 420 f/n/) to make it a non-breathable sheet.
Furthermore, before drying the latex, knitted stockinette fabric (AA 74
80 f/lt? ) and then dried. In this way, an overlay sheet was obtained which had a non-porous decorative surface layer and an air-permeable porous layer on the back surface.

Example 1. When overlay molding is performed in the same way using the same mold as above, the overlay sheet is first placed over the lower mold so that the surface of the needle punch carpet is in contact with the lower mold matte metal, and then the overlay sheet is molded along the outer surface of the lower mold. The folded parts at the four corners of the overlay sheet were cut and removed in advance. The old barley sheet is placed over the bottom mold with the knitted fabric surface facing up, and two heating blanks are placed on top of this! Immediately after that, the upper mold was lowered and press molding was performed. The inner surface of the box, which is a molded product, has a strong needle punch carpet 9! A sealed molded article was obtained. The peel strength was two-dimensional.

[Brief explanation of drawings]

Figures 1 to 3 are for explaining the present invention in detail. Figure 1 is an explanatory diagram showing the blank heating process, and Figure 2 is a diagram showing the blank and overlay sheet set on the press molding die. A cross-sectional view showing the state, and Figure -3 is a cross-sectional view showing the secured state of the press molding die. 1-Blank (fiber-reinforced thermoplastic 11j sheet) 1'-Heating blank 2-Overlay sheet 2m-Non-breathable decorative skin 2b-Breathable porous layer 3-Infrared heating furnace 4-Lower mold 4a-mold Surface 6-Upper mold 6a-Mold surface Patent applicant Ube Nitto Kasei Co., Ltd. Agent Patent attorney - Ken Iro Saya box 1 Figure 2

Claims (2)

[Claims] (1) A core made of a fiber-reinforced thermoplastic resin sheet molded into the desired shape, and a
A laminated molded product consisting of a breathable porous sheet whose surfaces are heat-sealed and a non-breathable decorative skin is formed on the surface. (2) In a molded product of a desired shape by placing a heat-softened fiber-reinforced thermoplastic @J resin receipt press mold on one mold surface and pressurizing the other mold, A breathable porous layer is laminated on the back side of a decorative skin having a non-breathable decorative surface, and is integrated with the decorative skin, and the integrated sheet is bonded so that the breathable porous layer is on one of the mold surfaces. A method for molding a laminate molded product, in which the fiber-reinforced thermoplastic resin sheet placed above is stacked so as to be in contact with the surface thereof, and then the other mold is held and pressurized.