JPH0263814A - Composite plastic product - Google Patents

Abstract

PURPOSE:To enable simultaneous molding of a composite plastic product by a method wherein parts molded of ABS resin beforehand is set into a blank space of the inside of a mold, a polyester resin layer containing styrene content is formed on the inside of the mold and the surface of parts, a boundary surface of both the resins are melted and bonded to each other under a contacting state of them and both the resins layers are cured. CONSTITUTION:The legs 2 made of ABS resin are set into blank spaces 61, 61 of the inside of a female mold 6, unsaturated polyester resin comprised of resin and a curing agent is laminated along with a glass mat by a hand lay-up method and a back layer 10 of 1-2mm thick is formed. When the same is left as it is for 2-3 hours at a temperature of 50-80 deg.C under this state, the unsaturated polyester resin of the back layer 10 is cured. At the same time boundaryless melting and adhesion where both the resins form a harmonious whole through compatible action of styrene content within both the resins are performed in the vicinity of a boundary 11 of the leg part made of the ABS resin.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a composite plastic product made by bonding different plastic parts to the main body of a plastic product.

(Prior art and its problems) Generally, the spray-up method and casting method are used to manufacture bathtubs, bath units, balcony floors, top plates, etc., but bathtubs and top plates formed using such methods Unlike injection molding methods, it is difficult to mold accessory parts such as legs or reinforcing ribs simultaneously with the main body. To attach accessory parts to the main body, as shown in Figure 5, After molding, the adhesive surface is sanded with paper, etc., and after degreasing, an epoxy or urethane adhesive B is applied to adhere the accessory part P, or as shown in Figure 6, the accessory part P is attached to the interior. After being temporarily fixed as a material, it is overlaid with a glass mat and resin R and then hardened to attach it by post-processing.

Therefore, there are problems in that the mounting is likely to be misaligned and loose, and the mounting strength is likely to be insufficient.

In order to solve this problem, a method has been proposed in which the attached parts are fixed to the main body at the same time as the main body is molded, instead of the above-mentioned attachment by post-processing (Japanese Patent Application Laid-Open No. 55-32681). Even if the same resin is used for the main body side and accessory parts side, the pressurization during compression molding alone will not provide sufficient adhesion, and it is currently difficult to manufacture composite plastic products by simultaneous molding.

(Problem of the Invention) An object of the present invention is to provide a composite plastic product that can firmly fix attached parts at the same time as the main body is cured by a spray-up method, a casting method, or the like.

(Means for Solving the Problems) The present invention uses polyester resin as a molding material for the main body molded by the spray amplification method, casting method, etc., while making the accessory parts pre-molded t\BS resin products. When these two are brought into contact, they melt and harden due to the compatibility between the styrene content in the polyester resin and the styrene content in the ABS resin at the contact interface between the two, which is faster than when other resins are combined. We discovered that it would be possible to obtain greater bonding strength, and we completed this product, which is a composite plastic product made by bonding different thermoplastic plastic parts to a thermosetting plastic main body. In the cavity inside the mold, AB
A component pre-molded with S resin is set, a polyester resin layer containing styrene is formed on the inner surface of the mold and the surface of the component, and the boundary surfaces of both resins are melted and bonded to each other under the state of contact between the two resins. , a composite plastic product made by curing a polyester resin layer.

Examples of polyester resins that can be used in the present invention include unsaturated polyester resins containing styrene, such as U-Pica 4080 (manufactured by Nippon U-Pica Co., Ltd.).

On the other hand, when using ABS resin as a molding material for accessory parts, it is necessary that the styrene content of both parts is highly compatible when the molded product is in contact with uncured polyester resin. (manufactured by Toshiku Co., Ltd.).

Spraying or casting polyester resin is usually carried out under the following conditions.

Curing temperature: 50 to 80°C Curing time: 2 to 3 hours As shown in FIG. 1, a product to which the present invention is applied includes a polyester resin hastab body 1 and a leg portion 2 made of a BS lubricant layer 2I. It would be possible to attach them by simultaneous molding, but as shown in Fig. 4, I attached A B S resin h11 strength ribs 4 to the polyester resin top plate 3.
It is widely applicable when attaching ABS resin accessories to a polyester resin main body without attaching them via the S resin plate 5.

Regarding the attachment of the legs of the bathtub, first attach the ABS resin plate 5 to the bathtub body l by simultaneous molding, as shown in FIG.
In the same manner as the resin leg part 2 is attached, different parts of various sizes may be attached to the same mold.

Hereinafter, the present invention will be explained in detail based on examples.

(Example 1) The manufacturing of the bathtub will be explained in FIG.

As shown in FIG. 7(a), the inner cavity 61.6 of the female mold 6
Place the I\BS resin leg part 2 in 1, and add unsaturated polyester resin Lennon Upica 4080 (manufactured by Nippon Yubika 00ffl+) with the following composition.
A hardening agent, 1 part of methyl ethyl ketone peroxide, is laminated together with a glass mat by a hand lay-up method to form a hard layer 10 having a thickness of 1 to 2 mm. When left in this state for 2 to 3 hours at a temperature of 50 to 80°C, the unsaturated polyester resin of the back layer 10 will harden, but at the same time, the styrene content in both resins will be Due to the compatibility of the two, seamless melt adhesion is performed in which the two become one.

On the other hand, as shown in Fig. 7 (b), the male mold 7 used separately
Apply a gel coat of hisphenol polyester resin to the surface to form a clear gel coat layer 12 with a thickness of 0.3 to 0.5 mm, and cure.

After that, as shown in FIG. 7(c), the female mold 6 and the male mold 7 are overlapped, and the back layer lO and the clear gel coat layer 12 are layered.
In the space between the
IWJ (methyl ethyl ketone peroxide) curing accelerator
0.5 part coloring agent and others Approximately 1 part of dung powder is injected from the injection lower 1 that forms the drainage hole of the bathtub, and left to harden at 50 to 80°C for 2 to 3 hours to form resin concrete. Form layer 13.

After the entire bathtub was cured, the mold was opened and the bathtub shown in FIG. 7(d) was taken out, and a joint strength test of the legs was conducted. Dimensions of the legs are as shown.

That is, in the state shown in Fig. 8, height H = 1100 mm to 2
A weight W of kg is dropped onto the leg 2, and the impact energy is 21
．． 6 kg-m"/see", but it withstood it.

On the other hand, the conventional resin concrete legs glued with urethane adhesive will be destroyed by the impact energy from the height H=1100mm,
withstood impact energy from Therefore, it can be seen that the composite plastic product manufactured by the method of the present invention can improve the bonding strength by at least 10%.

(Example 2) B X L = 40 x 80 on the inner surface of the female mold for bathtub molding
mm.

Create a space with a depth of approximately 5 mm, and use a thickness of 5 mm to fit the space.
A bathtub is molded in the same manner as in Example 1 by setting an ABS resin plate of It was bonded with a dope (ABS resin dissolved in methyl ethyl ketone) and cured. The adhesive strength of Example 2 was almost the same as that of Example 1.

(Effects of the Invention) As is clear from the above description, according to the present invention, in a composite plastic product formed by bonding different thermoplastic plastic parts to a thermosetting plastic main body, the outer surface of the main body is formed. AB in the cavity inside the mold for
A component pre-molded with S resin is set, a polyester resin layer containing styrene is formed on the inner surface of the mold and the surface of the component, and the boundary surfaces of both resins are melted and bonded to each other under the state of contact between the two resins. Since the polyester resin layer is allowed to harden, it is possible to mold the composite plastic product at the same time, and there is no misalignment between the two, and the manufacturing cycle time can be shortened. Moreover, unlike normal bonding, the styrene monomer invades the bonding interface, so as shown in FIG. 2, they mix with each other at the main body side contact interface If, and high bonding strength can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing the joined state of the legs of a bathtub, which is a specific example of the product according to the present invention, Fig. 2 is an enlarged view of the joined part, and Fig. 3 shows a modification of the joining mode shown in Fig. 1. FIG. 4 is a sectional view showing a joining mode of a second embodiment of the present invention, FIGS. 5 and 6 are sectional views showing a joining mode of a conventional bathtub, and FIGS. D) is an explanatory diagram showing the manufacturing process of the present invention, and FIG. 8 is an explanatory diagram of a bonding strength test. 1...Bathtub body, 2...Legs 3...Top plate, 4...Reinforcing ribs, 5...ABS resin plate 6...Female type, 7...Male type

Claims (1)

[Claims] 1. In a composite plastic product in which different thermoplastic plastic parts are adhered to a thermosetting plastic main body, AB
A component pre-molded with S resin is set, a polyester resin layer containing styrene is formed on the inner surface of the mold and the surface of the component, and the boundary surfaces of both resins are melted and bonded to each other under the state of contact between the two resins. , a composite plastic product characterized by being made by curing a polyester resin layer.