JPS6280034A - Composite molded shape - 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] [Field of Industrial Application] The composite molded product of the present invention can be used as lining insulation material for refrigerator bodies and doors, door materials for show window cases and unit baths that require heat insulation, It is useful for automobile interior materials such as automobile bumpers and door trims that require cushioning properties, surfing boards, etc.

[Prior art]

The body and doors of the refrigerator are coated with a styrene resin (acryloni) and IJ-butadiene-styrene copolymer (IJ-butadiene-styrene copolymer) to prevent rust on the baked-on stainless steel and copper plate structural base material (outer frame) and to form shelves. (commonly known as rABsJ) sheet by vacuum forming, pressure forming, forming using a combination of vacuum and pressure forming (hereinafter, these forming methods are collectively referred to as 1 thermoforming), or injection molding. In addition, instead of ABS lining material, it has excellent surface gloss, low water absorption, and
The use of polypropylene lining material, which is also advantageous for intravenous injection, has been proposed.

In order to improve the heat insulation properties of these lining materials, it has been proposed to interpose foamed polyurethane between the structural base and the lining material (Japanese Patent Laid-Open No. 60-97841).

In addition, door materials for unit baths are currently made of polyvinyl chloride sheets, but when used at high temperatures,
There is a problem that the aluminum sash frame is corroded by the chlorine gas generated by decomposition, so in order to improve this problem, two polypropylene sheets are attached to the aluminum sash frame instead of using a polyvinyl chloride sheet, and the aluminum sash frame and the sheet are enclosed. Consideration is being given to filling the empty space with polyurethane foam to give it more rigidity as a door.

Furthermore, with the conversion from metal to resin for interior materials such as automobile doors (IJs), filling polyurethane foam by injection method is being considered for the purpose of cushioning or heat insulation.

As described above, there is a demand for composites of resin materials and foamed polyurethane in resin products with various complex shapes.

[Problem that the invention seeks to solve]

However, the resin material is usually a sheet or a sheet molded by thermoforming or injection molding, and when polyolefin resin in such a shape is used,
Due to insufficient adhesion to foamed polyurethane, voids are formed, which has the disadvantage that the purpose of rigidity and heat insulation cannot be fully achieved.

In order to improve the adhesive strength between this resin material and foamed polyurethane, it is possible to apply a liquid adhesive or adhesive liquid or to treat the surface with chemicals (Japanese Patent Application Laid-open No. 60-97841), but this increases the number of coating and surface treatment steps. The addition of complicated steps is not desirable.

Furthermore, the resin layer that adheres to the urethane foam needs to be resistant to corrosion by the Freon gas mixed in the urethane.

The present invention eliminates such processing steps, is resistant to corrosion by Freon gas, and is inexpensive and advantageous in terms of cost and adhesion to urethane foam by blending an ethylene acrylic acid copolymer or the like with an olefin resin that adheres to urethane foam. It improves strength.

(Structure of the Invention) The present invention provides a composite molded product having a structure in which an olefin resin molded product and a urethane foam are integrally laminated via a resin layer having the following composition.

Resin layer composition N, olefin resin 40-85% by weight B), MF
60 to 15% by weight of ethylene/acrylic resin with an R of less than 30y/10min The recovered olefin resins include polyethylene, polypropylene, ethylene/propylene copolymer, ethylene/propylene/butene copolymer, etc. Resin can be used,
These can be used alone or as a mixture. Particularly preferred is a propylene/ethylene block copolymer containing 2 to 12% by weight of ethylene or a mixture of 50 to 90% by weight of polypropylene and 50 to 10% by weight of polyethylene.

Resins such as polyamide, ABS, and ethylene/vinyl acetate copolymers, stabilizers, rubbers, pigments, and inorganic fillers may be blended with this olefin resin.

(The ethylene/acrylic acid copolymer of the Bl component is JI
MFR measured at 190°C according to the regulations of SK-6758
is less than 30y/10 minutes, preferably 2 to 20y/lo, and is a relatively high molecular weight resin obtained by random copolymerization of 70 to 99% by weight of ethylene and 30 to 1% by weight of acrylic acid. It is resin. Such items are "Yukalon EAA A221M', "Yukalon EAAA200'S @ Yucalon EAA XA21" from Mitsubishi Yuka ■.
0S" (all product names).

If the concentration of component (B) in the ethylene/acrylic acid copolymer in the resin composition is less than 15% by weight, the adhesion between the urethane foam and the resin layer will be low, making it impractical. vice versa,
If it exceeds 60% by weight, mold release properties will be poor when the laminate sheet is subjected to vacuum forming, press forming, pressure forming, or injection molding. However, in the case of blow molding, since the resin layer surface is the inner surface of the hollow molded body, such troubles regarding mold releasability can be ignored.

In order to improve such mold releasability, a styrene resin may be added if necessary to reduce the amount of ethylene/acrylic acid copolymer added. Such styrene resins include polystyrene, ABS, and SBS.

SA, HIPS, etc. can be used. Among these, ABS
O has higher adhesion between the urethane foam and the resin layer.

However, the olefin resin of component (4) in the resin alone does not have adhesive properties with the urethane foam.

The resin layer is melted and mixed using an extruder, supplied to an extrusion die and extruded into a sheet or polyson shape, and then vacuum formed, compression molded, or blow molded, and is used as a refrigerator lining material or a surfboard.

Molded objects such as bumpers are injection molded.

The thickness of the molded body (resin layer) is 0.5 to 15-1, preferably 2 to 5I+Ill+, and the surface of these molded bodies may be subjected to corona discharge treatment, flame treatment, or plasma treatment if necessary.

(Composite molded product) A composite molded product is a composite molded product in which a urethane foam and a resin layer are bonded together.

In the case of a surfing board, a foaming urethane liquid is injected into the hollow portion of the blow-molded laminate and foamed.

When used as interior material for a refrigerator, as shown in Fig. 1, a formwork (1) made of decorative steel plate and the vacuum-formed laminate (2) are used.
A foamable urethane solution (4) is injected into the cavity (3) formed by the mold, which is then foamed and hardened to form the mold (
A multi-layered structure in which 1), the urethane foam (4'), and the lining material (2) are integrated is manufactured.

Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that parts and parts in the examples are based on weight.

Sheet manufacturing example Example 1 Resin bonded to urethane foam: 90% by weight of a crystalline propylene/ethylene block copolymer with a L/N content of 5% by weight, MF R0.5P/10 minutes, and a residual amount of 98% by weight after extraction with boiling heptane, and an ethylene block copolymer manufactured by Mitsubishi Yuka ■.
Acrylic acid (8.5wt%) copolymer “EAA A2”
21M' (trade name, MFR7f/10 minutes) at 20% by weight was kneaded using an extruder, extruded into strands, and cut into pellets.

The above pellets were processed at 230C using an extruder with a diameter of 90mβ.
The mixture was melt-kneaded and supplied to a manifold flat die with a width of 700 wr. The molten sheet extruded from the die has a width of 8
A solidified sheet was sequentially cooled and solidified using three rolls of 00 m. The temperature of the rolls is 40℃, 80℃, 6 from the roll closest to the die.
The temperature was 0° C., and the rotation speed of the roll was 1.5 m/min. The sheet thickness was 1.5 mm.

Example 2 The abbreviations in the table are as follows.

PP: Propylene/ethylene block copolymer E-AA
: Ethylene/acrylic acid copolymer A200K : Ethylene/acrylic acid copolymer manufactured by Mitsubishi Yuka ■ (acrylic acid content 7% by weight, MFR 5y/10 min) XA210S : Ethylene/acrylic acid copolymer manufactured by Mitsubishi Yuka ■ (Contains acrylic acid, 19% by weight, MFR 17F/10 minutes) A221M: Ethylene/acrylic acid copolymer manufactured by Mitsubishi Yuka (acrylic acid content: 8.5% by weight, MF R7F/LO) PS2 Mitsubishi Monsanto Kasei@Encyclopedia Polystyrene “Dialex HT516” (product name) SBS: Asahi Kasei ■SBS “Toughprene A” (product name) Example 1 Using a molding machine, the product was introduced into a heating furnace set at about 230°C.
Compressed air (5,0t, v/cd) and reduced pressure (-soomHg
) was used in combination with plug assist molding (drawing ratio H/D=
1/ ). The release properties of the sheet were good, and the plug was easily separated from the sheet.

After drilling an injection port in a part of this shaped sheet, this sheet is inserted into the stainless steel frame that is the frame of the refrigerator body, and then the space (cavity) formed by the frame and the shaped sheet is inserted. From the injection port inside, add a two-component foaming urethane solution - HM-1510 manufactured by Polyurethane Kagaku Kasei ■.
1 (trade name) was injected, foaming started 10 seconds later, and the space was completely filled with urethane foam 1 minute later. The density of this urethane foam is 0.05y
It was /-. The same operation was repeated 20 times to obtain 20 composite molded body samples.

After 24 hours, the sheet with the urethane foam adhered to it was cut out, and the adhesion between the urethane foam and the sheet was measured by the following method.

After separating the urethane foam from the sample piece by hand, use a knife to remove the urethane foam from the remaining urethane foam.
Next, adhesive tape was pasted onto the squares, and when the adhesive tape was vigorously peeled off from the sheet, the squares of urethane foam remaining on the sheet side were examined.

The results are shown in Table IK.

The evaluation criteria for adhesion are as follows.

It is weak and the sheet easily peels off from the interface with the urethane foam.

A composite molded body was obtained in the same manner except that the above was replaced.

Table 1 shows the adhesion between the urethane foam and the sheet of these composite molded bodies.

Example 7 Propylene/ethylene block copolymer 80% by weight used in Example 1 and ethylene/acrylic acid copolymer “A22”
A 1M"20% by weight mixture was melted and kneaded at about 220℃ using an extruder, fed to one die, extruded into a parison shape, and then blow-molded. A molded article for a surfing board was obtained.

A two-component urethane solution was injected into the hollow part of this molded body and foamed to obtain a surfing board.

The adhesion between the urethane foam and the resin layer of this product was stronger than that of Example 2.

Example 8 Resin: The same resin as in the example was used. (PPs.

% by weight, E-AA”A221M’20% by weight).

Using an 800 ton injection molding machine, injection molding was carried out at a temperature of about 220° C., an injection pressure of 100 Ail/ca, and a mold temperature of 60° C. to obtain a molded body for a bumper.

This molded product was placed in a foam frame, and a two-component urethane solution was injected and foamed to obtain a bumper for an automobile.

The adhesion between the urethane foam and the molded product is shown in Table 1.
Shown below.

[Brief explanation of drawings]

The figure is a sectional view showing one embodiment of the present invention. In the figure, 1 is a stainless steel frame, 2 is a resin sheet (lining material), 3 is a capacitance, 4' is a urethane foam, and 5 is an injection port. .

Claims (1)

[Claims] 1) Composition of the resin layer of a composite molded product having a structure in which urethane foam and a resin layer having the following composition are integrally laminated A) Olefin resin 40 to 85% by weight B) MFR of 30 g /Less than 10 minutes ethylene/acrylic acid random copolymer 60-15% by weight 2) Olefin resin has ethylene content of 2-12% by weight
The composite molded article according to claim 1, which is a propylene/ethylene block copolymer. 3) The composite molded article according to claim 1, wherein the olefin resin is a mixture of polypropylene and polyethylene, and the blending ratio is 50 to 90% by weight of polypropylene and 50 to 10% by weight of polyethylene. .