JPS6280036A - 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 as automobile interior materials such as automobile bumpers and door trims that require cushioning properties, surfboards, etc.

[Prior art]

The main body and door of the refrigerator are made of baked-on stainless steel or steel plate to prevent rust from forming the structural base material (outer frame) and to form the shelves. ) A lining material obtained by vacuum forming, pressure forming, or forming using a combination of vacuum and pressure (hereinafter, these forming methods are collectively referred to as thermoforming) is provided. Furthermore, instead of the ABS lining material, it has been proposed to use a polypropylene lining material that has excellent surface gloss and low water absorption.

In order to completely 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).

Additionally, Uni and Topas door materials are currently made from 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 sheets of derovirene are added to the aluminum sash frame instead of using a polyvinyl chloride sheet.Aluminum sash frame Consideration is being given to filling the space surrounded by the sheet with polyurethane foam to provide rigidity for the door.

Furthermore, with the transition from metal to resin for interior materials such as automobile door trims, 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.

[Problems that the invention attempts 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,
Foaming? Due to the insufficient adhesion with urethane, 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 processes is not desirable.

The present invention eliminates such a treatment step and improves the adhesive force with the urethane foam by blending an ethylene/acrylic acid random copolymer or the like into the olefin resin that comes into contact with the urethane foam.

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

Resin composition A) Olefin resin 65-95% by weight B) Ethylene/acrylic acid random copolymer 35-5% by weight The olefin resin of component A) is a propylene homopolymer, which has propylene as its main component. and ethylene,
Random copolymers or pro-copolymers with olefins such as butene-1, hexene, 4-methyl-4-ten-1, polypropylene such as maleic anhydride raft polypropylene; high-density polyethylene, low-density polyethylene,
Polyethylenes such as linear polyethylene and ethylene/vinyl acetate copolymers can be used, and these can be used alone or as a mixture.

In particular, pyrene-ethylene pro- or polypropylene copolymers or polypropylene with an ethylene content of 2 to 12 weight ratios of 50 to 9
It is preferable to use a mixture of 0 weight borage and polyethylene 50 to IO weight % because it allows for good deep drawability during vacuum forming and has high adhesion between the molded product and the urethane foam. .

B) Component ethylene/acrylic acid random copolymer is:
M measured at 190°C according to JISK-6758
The resin has an FR of 30 to 40 ON/10 minutes, which contains 70 to 99% by weight of ethylene and 30 to 1% by weight of acrylic acid.
It is a relatively low molecular weight resin obtained by random copolymerization of Such a product is sold by Mitsubishi Yuka Co., Ltd. under the name Yucalon EAAA500W (trade name).

If the concentration of component B) in the ethylene/acrylic acid random copolymer in the resin composition is less than 5% i1%, the adhesion between the urethane foam and the resin molded article will be low, making it impractical. On the other hand, if it exceeds 35% by weight, mold release properties will be poor when a sheet made of the resin composition is vacuum formed, press formed, pressure formed, or the resin composition is injection molded.

In order to improve such mold releasability, if necessary, 25% by weight or less, preferably 5 to 10% by weight, of styrene-based fat is added, and the amount of ethylene/acrylic acid copolymer added is doubled:
It may be reduced to ifS.

Such styrene-based materials (such as polystyrene,
Styrene φ butadiene/styrene block copolymer (S
BS), styrene-acrylonitrile copolymer (S
A), ABS, Noiin Sectopolystyrene (T
(IPS) etc. can be used. Among these, Mo ABS
(7) The adhesion to the urethane foam is lower.O However, the olefin resin as a captive component in the resin alone does not have adhesion to the urethane foam.

The resin composition having this composition is melt-kneaded using an extruder, extruded into a sheet shape or a non-stick shape, and then vacuum formed, compression molded, blow molded, and cooled to 6 tons lff.
1. Surfing is used as the lining material and the outer skin material for single-handed.

Molded products such as bumpers are obtained by injection molding a resin composition into a mold.

The surface of these molded articles may be subjected to corona discharge treatment or plasma treatment, if necessary.

(Composite molded product) The composite molded product is obtained by bonding the resin molded product and urethane foam together.

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

When used as an interior material for a refrigerator, as shown in Figure 1, a mold made of decorative steel plate (1) and the vacuum-formed molded product (2) are used.
A foamable urethane solution (4) is injected into the cavity (3) formed by the process, and then foamed.

By curing, a composite molded article in which the formwork (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 sections in the examples are based on weight.

Sheet manufacturing example Example 1: Crystalline propylene-ethylene block copolymer with 5% ethylene content, MFR 0.51/10 minutes, boiling hebutane extraction residue 98% by weight, and Mitsubishi Yuka (flavor)
! l"j Ethylene/acrylic [2 (20wt%) random copolymer "500W" (trade name, MFR300g/
(10 minutes) A mixture of 10% by weight was kneaded using an extruder, extruded into a strand, and cut into a pellet.

The above resin pellets were processed using an extruder with a diameter of 90 mm.
℃ and fed into a flat die with a width of 700 mm.

The molten sheet extruded from the die was sequentially cooled and solidified using three rolls having a width of 700 mm, and then subjected to corona discharge treatment to obtain a sheet for vacuum forming.

The temperature of the rolls is 10℃, 95℃ from the roll closest to the die.
℃, 50℃, and the rotation speed of the roll is 1.5 m/
It was a minute. The sheet thickness was 1.6 tones in total.

Examples 2 to 9 Sheets were obtained in the same manner as in Example 1, except that the composition of the resin was changed as in Fit 1.

The abbreviations in the table are as follows.

PP: f-ropylene/ethylene block copolymer E-AA
: Ethylene/acrylic acid random copolymer A300W
: Ethylene/acrylic acid copolymer manufactured by Mitsubishi Yuka (a) (
Acrylic plate content 20 fL%, IξR300V 10 minutes) A221M: Ethylene-acrylic acid copolymer manufactured by Mitsubishi Yuka (Mahi) (acrylic acid content 8.5, R'l/10 minutes) PS: Mitsubishi Holistyrene “Dialex HT516” (product name) manufactured by Monsando Kasei Co., Ltd. SBS: Asahi Kasei (
Co., Ltd.;d SBS "Tafrun A" (trade name) Example 1 The sheet obtained in Example 1 was molded into about 2
Place it in a heating furnace set at 30°C and fill it with compressed air (5.0 kg/
crrr? ) and reduced pressure (-600 mmHg) to perform plug assist molding (drawing ratio H/D=1/1). The sheet had good μ and lt type properties, 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 formed by the frame and the shaped sheet ( Inject a two-component foaming urethane solution "HM-1" manufactured by Polyurethane Kagaku Kasei Co., Ltd. into the cavity from the injection port.
When 510'' (trade name) was injected, foaming started after 10 seconds, and after 1 minute, the space was completely filled with urethane foam.The density of this urethane foam was 0.
05! y/Confucian 3. The same operation was repeated 20 times to obtain 20 samples of retained composite structures η.

A sheet of MML, t, = urethane 7 ohm was cut out for 24 hours, and the adhesion between the urethane 7 ohm and the sheet was measured by the following method.

The urethane foam was removed by hand from the sample piece, and the sheet with the remaining urethane foam was cut with a knife for 10 minutes.
0 mortar squares were cut into pieces, then adhesive tape was pasted on the squares, and when the adhesive tape f was vigorously peeled off from the sheet, the urethane foam remaining on the sheet ω11 was examined.

The results are shown in Table 1.

The evaluation criteria for adhesion are as follows.

○: Cohesive failure of urethane foam, 81100 Adhesive part of square, top to ■: Cohesive failure of urethane foam and interfacial peeling between resin molded product and urethane occur simultaneously.

, 5080 squares -10,000 koku to 10,000 koku'' ×: The adhesion between the urethane foam and the resin molded product is weak, and the sheet is easily peeled off from the interface with the urethane 7 ohm.

Square Knee 9 - 1 Examples 2 to 5, Comparative Examples 1 to 3 Composite molded bodies were obtained in the same manner except that the resin sheets in Example 1 were replaced with those in Examples 2 to 7.

Table 1 shows the adhesion between the urethane 7 ohm and the sheet of these composite molded bodies.

Example 5 A resin composition was made of a mixture of 80% by weight of the glopyrene/ethylene block copolymer used in Example 1 and 20% by weight of the ethylene/acrylic acid random copolymer "500 W", extruded into a parison shape, and then A hollow molded body for a two-fin board was obtained by blow molding. .

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

The adhesion between the urethane 2 ohm and the resin hollow body of this product was stronger than that of the urethane 2 ohm and the resin hollow body.

Example 6 80-layer crystalline propylene-ethylene block copolymer with ethylene content of 15% by weight, MFR 1.2 g/10 minutes, back side 20-layer ethylene-acrylic acid random copolymer "A300W" used in Example 1 i% mixture as a resin composition, a Mitsubishi Natco injection molding machine (800 tons) was used, the resin temperature was 230°C, and the injection pressure was 1,000 kg/c.
The molded product was molded by injection molding at a mold temperature of 40° C. to obtain a molded product for a passenger car pan/throat. This molded product was assembled into a foam frame, and a foamable two-component urethane resin was injected and foamed to obtain a car pan. Clothing 1 shows the adhesion of this molded article to the urethane foam.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention. In the figure, 1 is a stainless steel frame, 2 is a resin molded product (lining material), 3 is a cavity, 41 is a urethane foam, and 5 is an injection port.

Claims (3)

[Claims] (1) A composite molded product having a structure in which urethane foam and a resin molded product having the composition shown below are laminated together. Resin composition A) Olefin resin 65-95% by weight B) Ethylene/acrylic acid random copolymer with MFR of 30 g/10 minutes or more 35-5% by weight (2) Olefin resin has an ethylene content of 2 to 12% by weight
The composite molded article according to claim 1, which is a propylene/ethylene block copolymer. (3) Olefin resin is polypropylene 50-90
The composite molded article according to claim 1, which is a mixture of 50 to 10% by weight of polyethylene and polyethylene.