JPH08258200A - Thermoplastic resin composite - Google Patents

Abstract

PURPOSE: To provide a resistibility against chemical substances generated from a polyurethane foam body, and also against erosion during the period of thermoforming or in storage thereof by laminating a compound layer consisting of a polyester resin layer and ethylene, vinyl alcohol copolymer resin layer on a thermoplastic resin layer via an adhesive resin layer. CONSTITUTION: The thermoplastic resin composite is made by laminating a compound layer 4a consisting of a polyester resin layer 4a and ethylene, vinyl alcohol copolymer resin layer 4b on a thermoplastic resin layer 2 via an adhesive thermoplastic resin layer 3. For the thermoplastic resin layer 2, styrenic resin and polyolefinic resin are employed preferably. Further, graft modified polyolefinic resin or a blended matter of this resin and polyolefinic resin is preferably used for the adhesive thermoplastic resin layer 3. As unsaturated carboxylic acid to be grafted, maleic acid or its acid anhydride is used, and a rate of graft is preferably 0.01-10wt.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composite having resistance to CFCs and CFC substitutes. More specifically, it has resistance to CFCs and CFC substitutes (resistance to swelling, cracking, crazing, etc.) and can be preferably used as a heat-moldable laminate for a heat insulating material such as a refrigerator liner. The present invention relates to a thermoplastic resin composite that can be obtained.

[0002]

BACKGROUND OF THE INVENTION Refrigerator walls generally consist of an outer metal cabinet layer, an intermediate foam foam core layer, and an inner plastic liner layer.
The plastic liner layer of the inner layer is generally AB
It is made of S resin (acrylonitrile / butadiene / styrene copolymer resin) or HIPS resin (high impact polystyrene resin) material. The heat insulating foam core layer of the intermediate layer is generally formed of a polyurethane foam material. The foaming agent used in the polyurethane foam material is used as a foaming agent during foam molding and contributes to foaming of the raw material, but remains in a foamed product after foam molding. are doing. As such a foaming agent, those currently commercially used include CFC (CFC-11), totally halogenated methane, fluorotrichloromethane and the like.

However, since the above-mentioned CFCs cause the destruction of the ozone layer, the use of CFCs has been suppressed in recent years from the viewpoint of global environment conservation, and efforts have been made to find alternative CFCs. It continues. Recently, 2-fluoro-2,2, which is a halogenated hydrocarbon having at least one hydrogen atom, has been used as the alternative CFC.
-Dichloroethane (HCFC-141b), 2-dichloro-1,1,1-trifluoroethane (HCFC-12)
3) was proposed.

However, such 2-fluoro-
2,2-Dichloroethane (HCFC-141b), 2-
Dichloro-1,1,1-trifluoroethane (HCFC
-123) alternative CFCs and CFCs (CFC-11)
Exerts a chemical action on the plastic liner layer used as the inner layer of the wall of the refrigerator, and the plastic liner layer causes stress whitening and a decrease in impact resistance (brittleness), resulting in a marked decrease in commercial value. I will let you.
In particular, it has been reported that the foaming agents of alternative CFCs such as HCFC-141b and HCFC-123 have a stronger chemical action on the plastic liner than CFCs (CFC-11). In this way, CFC alternatives for blowing agents erode plastic liners generally
It is considered to occur when the foaming agent after foam molding becomes a liquid by condensation. Therefore, the condensation of the foaming agent occurs during the "heating-cooling" step in manufacturing the refrigerator plastic liner. In particular, since it is cooled during aging after foam molding, this condenses the foaming agent and causes erosion. In addition, such condensation of the foaming agent,
It also occurs during the transportation and storage of the product, during which time the plastic liner will be eroded. Therefore, the sheet for composite heat insulating material used as a plastic liner for the inner layer of the wall of the refrigerator is used in a state of being in contact with the urethane foam, and therefore has resistance to chlorofluorocarbon and alternative chlorofluorocarbon (swelling, cracking, crazing, etc.). It is desirable to have a plastic composite laminate having resistance to ().

[0005]

Due to the above problems, it occurs from the polyurethane foam foamed with the above-mentioned CFC (CFC-11) or CFC substitute (HCFC-141b or HCFC-123). Thermoplastic resin made of thermoformable plastic material that is resistant to chemical substances (swelling, cracking, crazing, etc.) and is not easily corroded during aging, transportation or storage The purpose is to obtain a composite.

[0006]

[Means for Solving the Problems]

[Summary of the Invention] The present inventors have conducted intensive studies in view of the above problems, and as a result, have resistance to CFCs and alternative CFCs, and have a CFC transmission rate that is practically negligible. The present invention has been completed by studying a thermoplastic resin composite having good adhesive strength with urethane foam. That is, the thermoplastic resin composite of the present invention is obtained by laminating a composite layer comprising a polyester resin layer and an ethylene / vinyl alcohol copolymer resin layer on the thermoplastic resin layer via an adhesive thermoplastic resin layer. It is characterized by that.

[Detailed Description of the Invention] [I] Thermoplastic Resin Composite (1) Layer Structure (a) Thermoplastic Resin Layer Thermoplastic resin 2 used in the thermoplastic resin composite 1 of the present invention As the thermoplastic resin, a thermoplastic resin selected from a styrene resin, a polyolefin resin, a vinyl chloride resin, and a blend thereof, or a material obtained by adding an inorganic filler or the like to them can be used. Among these, it is particularly preferable to use a styrene resin or a polyolefin resin.

Styrenic Resin The styrenic resin is a styrene monomer or an α-substituted styrene such as methylstyrene, a derivative monomer such as paratertiarybutylstyrene, paramethylstyrene, vinyltoluene or chlorostyrene. Homogeneous or copolymer, or the styrene monomer 1
Examples thereof include a copolymer of the seed and another copolymerizable monomer. Specifically, polystyrene, poly α-methylstyrene, a styrene-acrylonitrile copolymer (AS resin), a graft copolymer obtained by graft-copolymerizing one or more of the above-mentioned styrene-based monomers with butadiene rubber, for example, , High impact polystyrene (HIP
S), or a graft copolymer obtained by graft copolymerizing another copolymerizable monomer, such as an acrylonitrile / butadiene rubber graft styrene copolymer (ABS resin).

Polyolefin Resin As the above-mentioned polyolefin resin, α having 2 to 4 carbon atoms is used.
-A polyolefin resin containing olefin as a main component, that is, a crystalline polymer containing ethylene, propylene and butene-1 as a main component can be mentioned. Specific examples of these polyolefin resins include polyethylene, polypropylene, and polybutene-1, but these are not limited to homopolymers, and other carbon numbers may be used as long as they contain olefin as a main component. 2-20 α
-It also includes a copolymer with an olefin or a vinyl compound such as vinyl acetate, vinyl chloride, acrylic acid, methacrylic acid, or styrene. Further, these polyolefins may be a mixture.

Examples of the polyethylene include high-pressure low-density polyethylene (LDPE), high-density polyethylene (HDPE), ethylene / α-olefin copolymer,
Examples thereof include ethylene / vinyl acetate copolymers and ethylene / acrylic acid copolymers. Where ethylene / α
The α-olefin constituting the olefin copolymer is usually an α-olefin having 3 to 20 carbon atoms, specifically, for example, propylene, butene-1, hexene-1,
4-methylpentene-1, octene-1, decene-1,
Tetradecene-1, octadecene-1, etc., which can be used alone or as a mixture of two or more kinds.

Examples of the polypropylene include polypropylene (propylene homopolymer), propylene
Propylene random copolymers such as ethylene random copolymer and propylene / ethylene / butene-1 random copolymer (propylene content is usually 90 mol% or more, preferably 95 mol% or more), or propylene / ethylene block Propylene block copolymers such as copolymers (ethylene content is usually 0.3 to 40 mol%, preferably 1 to 30 mol%) and the like.

Examples of the polybutene-1 include butene-1 homopolymer, butene-1 · ethylene copolymer, butene-1 · propylene copolymer, butene-1 · 4-methylpentene-1 copolymer and the like. Can be mentioned.

Vinyl Chloride Resin The vinyl chloride resin may be a vinyl chloride homopolymer or a copolymer having a repeating unit derived from vinyl chloride as a main repeating unit. In particular,
Examples thereof include ethylene / vinyl chloride copolymer and ethylene / vinyl acetate / vinyl chloride copolymer resins. Among these, it is preferable to use polyvinyl chloride resin.

Inorganic Fillers Examples of inorganic fillers that can be added to the thermoplastic resin include calcium carbonate, magnesium carbonate,
Dolomite and other carbonates, calcium sulfate, magnesium sulfate, barium sulfate and other sulfates, calcium sulfite and other sulfites, talc, clay, mica, asbestos, glass fiber, glass beads, calcium silicate, montmorillonite, bentonite and other silicates To silicate minerals, metal powders such as iron, zinc and aluminum, metal oxides such as titanium oxide and aluminum oxide, metal hydroxides such as aluminum hydroxide, ceramics such as silicon carbide and silicon nitride, and whiskers thereof , Carbon black, graphite,
Carbon fiber etc. can be mentioned. These inorganic fillers may be used alone or in admixture of two or more kinds. Among the various inorganic fillers described above, it is preferable to use carbonates, sulfates, silicates, metal powders, and further it is preferable to use calcium carbonate, barium sulfate, talc, mica, zinc powder, and the like.
Particularly preferably used are talc and calcium carbonate. The blending amount of these inorganic fillers is 1
It is generally in the range of 50 parts by weight or less, preferably 1 to 50 parts by weight, and particularly preferably 3 to 40 parts by weight with respect to 00 parts by weight.

(B) Adhesive Thermoplastic Resin Layer Graft-Modified Thermoplastic Resin As the adhesive thermoplastic resin layer 3, a part or all of the thermoplastic resin used in the thermoplastic resin layer 2 is graft-modified. It is a graft-modified thermoplastic resin or a blend of the graft-modified thermoplastic resin and the thermoplastic resin. Among these graft-modified thermoplastic resins, it is preferable to use a graft-modified polyolefin resin obtained by graft-modifying a part or all of the polyolefin resin, or a blend of the graft-modified polyolefin resin and the polyolefin resin. Is.

As the unsaturated carboxylic acid or its derivative to be grafted, acrylic acid, maleic acid, fumaric acid,
It is an unsaturated carboxylic acid having 2 to 20 carbon atoms such as tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, or a derivative thereof. Examples thereof include acid halides, amides, imides, anhydrides and esters. Specifically, maleenyl chloride, maleimide,
Mention may be made of maleic anhydride, citraconic anhydride, monomethyl maleate, dimethyl maleate, glycidyl maleate and the like. Among these, it is preferable to use unsaturated dicarboxylic acids or their acid anhydrides, and it is particularly preferable to use maleic acid or these acid anhydrides.

Grafting amount The amount of the unsaturated carboxylic acid or its derivative to be grafted on the thermoplastic resin is generally 0.01 to 10
It is in the range of wt%, preferably 0.1 to 5 wt%.
If necessary, the trimming loss and the like of the laminate produced at the time of production is crushed, or the crushed product is pelletized and used in a thermoplastic resin layer, or,
As shown in FIG. 2, another layer such as a recycled resin layer 5 which is recycled, recovered and recycled may be provided between the thermoplastic resin layer 2 and the adhesive thermoplastic resin layer 3 for use. Between the composite layer 4 and the adhesive thermoplastic resin layer 3 described later,
Other layers can be provided and used. In particular, the adhesive thermoplastic resin layer 3 may be the thermoplastic resin layer 2 having the adhesive thermoplastic resin layer 3 provided on the front and back surfaces as shown in FIG. Further, as shown in FIG. 2, another layer such as a recycled resin layer 5 which is recycled for recovery and recovery may be provided between the thermoplastic resin layer 2 and the adhesive thermoplastic resin layer 3.

(C) Composite Layer Polyester Resin Layer As the polyester resin layer 4a of the composite layer 4, an aliphatic glycol such as ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol or hexamethylene glycol, cyclohexane is used. Aliphatic glycols such as dimethanol, aromatic dihydroxy compound units such as bisphenol, and aromatic carboxylic acids such as terephthalic acid, isophthalic acid and 2,6-naphthalene dicarboxylic acid, oxalic acid, succinic acid, adipic acid, sebacic acid A polyester resin formed from an aliphatic dicarboxylic acid such as undecadicarboxylic acid, an alicyclic dicarboxylic acid such as hexahydrodicarboxylic acid, or a dicarboxylic acid unit selected from two or more of these, As long as it shows plasticity, a small amount of triol or trica It may be modified with rubic acid or the like. Specific examples of these thermoplastic polyester resins include polyethylene terephthalate, polybutylene terephthalate, and polyethylene isophthalate / terephthalate copolymers.
The molecular weight of the polyester resin is not particularly limited, but usually, the relative viscosity (JIS-K6810, 98%
A polyester resin having a (measured in sulfuric acid) of 0.5 or more is used.

Ethylene / vinyl alcohol copolymer resin
Layer The ethylene / vinyl alcohol copolymer resin layer 4b of the composite layer 4 has an ethylene copolymerization ratio of 10 to 65.
Mol% ethylene / vinyl alcohol copolymer resin, at least 90% ethylene / vinyl acetate copolymer
It can be obtained by saponification as described above. An ethylene / vinyl alcohol copolymer having a copolymerization ratio of ethylene of 30 mol% or more, preferably 30 to 50 mol% is preferably used.

Complexation In the thermoplastic resin composite laminate 1 of the present invention, it is important to use the composite layer 4 in which the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer resin layer 4b are laminated. is there. The ethylene / vinyl alcohol copolymer has excellent CFC barrier properties and excellent thermoformability, but it absorbs moisture in a short time when exposed to the atmosphere, and foams during secondary molding (thermoforming) to give an appearance. As it gets worse
Resistance to CFCs and CFC substitutes decreases. It is considered that this is due to local thinning of the CFC barrier layer or formation of holes at the location where foaming occurred.

On the other hand, although the polyester resin has a strong initial adhesive strength to urethane foam and a CFC barrier property, it has poor thermoformability and causes necking during secondary processing (thermoforming), resulting in local film breakage. In some cases, the molded product does not exhibit the desired CFC barrier properties (whitening occurs). By using a composite layer consisting of two layers of an ethylene / vinyl alcohol copolymer resin and a polyester resin, it is possible to obtain CFCs and alternative CFCs that have good deep drawability without the above-mentioned problems and have a strong adhesive strength with urethane. And a laminate having durability is obtained. Further, the molded product obtained from the thermoplastic resin composite laminate having excellent thermoformability also has urethane adhesiveness, resistance to CFCs and alternative CFCs.

The thickness of each of the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer layer 4b in the composite layer 4 must be 10 μm or more, and the polyester resin layer 4a is generally 10 to 200 μm, preferably 20 to 15 μm.
The thickness of the ethylene / vinyl alcohol copolymer layer is 0 to 200 μm, and preferably 20 to 150 μm. The thickness ratio of the polyester resin layer 4a / ethylene / vinyl alcohol copolymer layer 4b is generally 1/5.
˜5 / 1, preferably 1 / 0.5 to 0.5 / 1, particularly preferably 1/1.

By using such a composite layer, it is possible to obtain a laminate having a good deep drawability and a good CFC barrier property with a strong adhesive strength with urethane. Particularly, in these composite layers 4, as shown in FIG. 1, the adhesive thermoplastic resin layer 3 side is placed on the ethylene / vinyl alcohol copolymer layer 4b.
By setting the polyurethane foam material layer 6 side to the polyester resin layer 4a, it is possible to further increase the resistance, which is preferable. When the adhesive thermoplastic resin layer 3 side is the polyester resin layer 4a and the polyurethane foam material layer 5 side is the ethylene / vinyl alcohol copolymer layer 4b, secondary molding by moisture absorption of the polyester resin layer 4a ( It is possible to avoid deterioration of physical properties due to foaming during thermoforming). Thermoplastic resin composite laminate 1 of the present invention
In the above, if only the polyester resin layer 4a is used as a single layer, foaming will occur during secondary molding. Also, if the ethylene / vinyl alcohol copolymer resin layer 4b alone is used as a single layer, film breakage will occur during secondary molding.

(D) Arbitrary layer recycled resin layer From the thermoplastic resin layer 2, the adhesive thermoplastic resin layer 3, and the composite layer 4 including the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer resin layer 4b. From the viewpoint of effective utilization of resources and economical efficiency, the recycled resin layer 5 is basically constituted, but is replaced with a part of the thermoplastic resin and is recycled and recovered to be regenerated.
Can also be provided. The thickness of the recycled resin layer 5 is 80% or less of the total thickness of the thermoplastic resin composite 1,
More preferably 50% or less, particularly preferably 10-40
%.

Polyurethane Foam Material Layer A polyurethane foam material layer 6 is provided on the side of the composite layer 4 comprising the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer resin layer 4b of the thermoplastic resin composite 1 of the present invention. Can be provided. The polyurethane foam material layer 6 is obtained by blending a polyurethane material with a foaming agent,
It is a layer foamed 10 to 200 times, preferably 50 to 150 times. As the foaming agent, a halogenated hydrocarbon having at least one hydrogen atom, specifically, Freon (CFC-11), total halogenated methane, fluorotrichloromethane, 2-fluoro-2,2-dichloroethane (HCFC -141b), 2-dichloro-1,1,1-
Examples thereof include trifluoroethane (HCFC-123). The polyurethane foam material layer 6 is used as a heat insulating material.

Metal Cabinet Layer As shown in FIG. 5, a metal cabinet layer 7 can be further provided on the polyurethane foam material layer 6 side. With such a structure, a structure suitable for the refrigerator liner 9 and the like can be obtained. The metal cabinet layer 7 is generally formed of a coated metal plate, and is formed into various shapes depending on its use. The metal cabinet layer 7 is the outermost layer, the polyurethane foam material layer 6 is provided on the inner side of the metal cabinet layer 7, and the thermoplastic resin composite 1 of the present invention is formed on the inner side of the metal cabinet layer 7 to form a heat insulating exterior and inner wall for a refrigerator. It can be used as an inner box.

(2) Laminate Layer Each of these resin layers is formed into a film or sheet and laminated as shown in FIG. As a stacking method,
Various methods can be adopted. Specifically, the laminate 4 of the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer resin layer 4b and the thermoplastic synthetic resin sheet layer 2 are molded in advance and bonded to the middle of these layers 2 and 4. The thermoplastic resin 3 can be melt-extruded and pressure-bonded with a roll or the like to be laminated. In addition, polyester resin 4a,
The ethylene / vinyl alcohol copolymer resin 4b, the adhesive thermoplastic resin 3 and the thermoplastic resin 2 may be melted and coextruded using a die having a feed block or a multi-manifold die. Also,
It is also possible to form a part of the layers in advance and then co-extrude and laminate other layers on the layer.

The layer structure of the thermoplastic resin composite laminate 1 of the present invention is such that the thermoplastic resin layer 2, the adhesive thermoplastic resin layer 3,
Further, although it is basically composed of a composite layer 4 composed of a polyester resin layer 4a and an ethylene / vinyl alcohol copolymer resin layer 4b, in addition to the layer structure shown in FIGS. Both outermost layers, as shown in FIG. 4, polyester resin layer 4a / ethylene / vinyl alcohol copolymer resin layer 4b / adhesive thermoplastic resin layer 3 / recycled resin layer 5 / thermoplastic resin layer 2 / recycled resin The layer 5 / adhesive thermoplastic resin layer 3 / ethylene / vinyl alcohol copolymer resin layer 4b / polyester resin layer 4a can also be used.

(3) Thickness The total thickness of the thermoplastic resin composite laminate 1 of the present invention is not particularly limited, but is generally 1.0 to 5 mm, preferably 1.5 to 3 mm. The thickness of the thermoplastic resin layer 2 is generally 400 to 4,970 μm, preferably 700 to 4,900 μm. The thickness of the adhesive thermoplastic resin layer 3 is generally 10 to 400 μm.
And preferably 50 to 200 μm. The thickness of the composite layer 4 of the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer resin layer 4b is generally 20 to 300 μm, preferably the total thickness of the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer layer 4b. Is 50 to 100 μm. The thickness of the composite layer 4 is 10μ
If it is less than m, it tends to be difficult to form a layer having a uniform thickness in the width direction, and if it exceeds 300 μm, it becomes economically unrealistic.

[II] Method for Processing Laminated Body After the inner box made of the thermoplastic resin composite 1 of the present invention is heat-molded, it is combined with the metal cabinet wall 7 to be the outer wall to form the inner box. The urethane foamable resin material 6 is injected into the space between the metal cabinet wall 7 on the outside and foamed to be integrated, and the metal cabinet layer 7 / polyurethane foam material layer 6 / polyester resin layer 4a and ethylene vinyl By forming the composite layer 4 including the alcohol copolymer resin layer 4b / adhesive thermoplastic resin layer 3 / thermoplastic resin layer 2, the outer wall and the inner wall for the refrigerator can be formed. The plastic inner box includes a polyurethane foam material layer 6
Since it is formed in the intermediate layer, it can be used as a heat insulating material (heat insulating wall) that prevents heat from escaping from inside the refrigerator. In addition, when thermoforming,
After heating to 40 to 180 ° C., an inner box having a length of 800 × width of 400 × depth of 380 mm was formed using a vacuum forming machine.

[III] Application As shown in FIG. 5, metal cabinet layer 7 / polyurethane foam material layer 6 / polyester resin layer 4a and ethylene
By forming a composite layer 4 composed of a vinyl alcohol copolymer resin layer 4b / adhesive thermoplastic resin layer 3 / thermoplastic resin layer 2, liner 9 for outer and inner walls of a refrigerator,
It can be used as a plastic inner box. In the thermoplastic resin composite 1 of the present invention, the composite layer 4 including the polyester resin layer 4a and the ethylene / vinyl alcohol copolymer resin layer 4b is formed on the side in contact with the polyurethane foam material layer 6. , Resistant to the CFCs used in the polyurethane foam material layer 6 and alternative CFCs, and the CFC transmission is so small that it is practically negligible. It has resistance (resistance to swelling, cracking, crazing, etc.) and is not easily corroded during aging, transportation and storage, and can be used as an outer wall, an inner wall for a refrigerator and a plastic inner box.

[0032]

EXAMPLES The present invention will be described in more detail with reference to the following examples and comparative examples. Example 1 Production of Thermoplastic Resin Composite As the thermoplastic resin layer 2, a high-impact polystyrene having a thickness of 1,800 μm (Dialex H manufactured by Mitsubishi Chemical Corporation) was used.
T-516), and on one side thereof, as an adhesive thermoplastic resin layer 3, a 100 μm thick maleic anhydride grafted polypropylene resin (MODIC F manufactured by Mitsubishi Chemical Corporation).
-3300F) as the composite layer 4 as the ethylene / vinyl alcohol copolymer layer 4b (Eval EP-E1).
51B, Kuraray Co., Ltd. 50 μm and polyester layer 4a (Mitsubishi Chemical Co., Ltd. Novamid 1030) 50 μm
The composite layer 4 having a total thickness of 2.0 mm is coextruded and laminated to form a three-layer structure (high impact polystyrene / maleic anhydride grafted polypropylene resin / ethylene.
A thermoplastic resin composite 1 of a composite layer of a vinyl alcohol copolymer layer and a polyester layer) was molded.

Evaluation Method (1) Urethane Adhesion Test pieces having a size of 30 cm × 30 cm were prepared from the thermoplastic resin composite 1, and a pair of closed foams were formed on the CFC barrier resin layer 4 side of the test pieces. It was placed in the jig. The distance between the pair of composites was 1 cm. Then, a polyurethane foaming chemical is introduced between the pair of composites in the jig to fill the space of the test piece with the polyurethane foaming chemical, and the thermoplastic resin composite 1 / polyurethane foam as shown in FIG. A composite structure 8 consisting of layer 6 / thermoplastic resin composite 1 was produced. 15 mm from the composite structure 8
Several 100 mm test pieces were cut out, and the thermoplastic resin composite was peeled off from the polyurethane foam layer. At that time, when the polyurethane foam layer was cohesively broken, it was judged that the adhesive strength was good, and when breakage occurred at the interface between the two (interfacial break), the adhesive strength was judged to be insufficient. Table 1 shows the results.

(2) Freon resistance and alternative flon resistance The above-mentioned composite structure 8 was repeatedly subjected to a heat cycle several times between -40 ° C and 60 ° C. By this thermal cycle,
Condensation and evaporation of the foaming agent occur at the portion where the surface of the composite structure 8 composed of the thermoplastic resin composite 1 / polyurethane foam layer 6 / thermoplastic resin composite 1 is exposed to the polyurethane foam layer 6. . Then, it was visually observed whether the test piece was attacked by the polyurethane foaming chemical and whitening, cracking and crazing occurred. Table 1 shows the results.

(3) Thermoformability This resin composite was measured using a large vacuum forming machine to a length of 800 mm.
A box-type refrigerator inner box having a width of 400 mm and a depth of 380 mm was molded, and a thermoforming test of the resin composite 1 was performed. The thermoforming conditions were the usual refrigerator inner box molding conditions. When the sheet surface temperature at the time of thermoforming was actually measured, it was 165 to 180 ° C. The evaluation was judged to be good when the shape of the mold was properly transferred to the molded product and the composite layer did not cause film breakage. Table 1 shows the results.

Example 2 In Example 1, polypropylene resin (Mitsubishi Polypro EC9) was used as the thermoplastic resin layer 2, and maleic anhydride grafted polypropylene resin (manufactured by Mitsubishi Chemical Co., Ltd.) was used as the adhesive thermoplastic resin layer 3. MODIC P-371
Except that K) was used, sheet molding was performed by coextruding and laminating in the same manner as in Example 1, urethane adhesiveness,
The CFC resistance, alternative CFC resistance, and thermoformability were tested according to Example 1. Table 1 shows the results.

Example 3 In Example 1, polypropylene resin containing a filler (Mitsubishi Polypro TX1088 manufactured by Mitsubishi Chemical Corporation) was used as the thermoplastic resin layer 2, and maleic anhydride grafted polypropylene was used as the adhesive thermoplastic resin layer 3. Sheet molding was performed by co-extruding and laminating in the same manner as in Example 1 except that a resin (MODIC P-300F manufactured by Mitsubishi Chemical Co., Ltd.) was used, and urethane adhesion, flon resistance and alternative flon resistance were obtained. A thermoformability test was performed according to Example 1. Table 1 shows the results.

Example 4 In Example 1, as the thermoplastic resin layer 2, high-impact polystyrene (Dialex HT manufactured by Mitsubishi Chemical Corporation) was used.
-516), except that a 30% blended pulverized product of the composite laminate was used, sheet formation was performed by coextrusion and lamination in the same manner as in Example 1, urethane adhesion,
The CFC resistance, alternative CFC resistance, and thermoformability were tested according to Example 1. Table 1 shows the results.

Example 5 The same as Example 1 except that a layer made of a pulverized product of the composite laminate was provided between the thermoplastic resin layer 2 and the adhesive thermoplastic resin layer 3. Sheet molding was carried out by coextrusion and lamination, and urethane adhesion, CFC resistance, CFC resistance resistance, and thermoformability were tested according to Example 1. Table 1 shows the results.

Example 6 Thermoplastic resin composites 1 to 30c molded in Example 1
A test piece with a size of m × 30 cm was prepared, and the test piece was placed in a closed jig so that the CFC barrier resin layer of the test piece and the metal plate (1 mmt) face each other. The distance between them is 1 cm
Met. Next, a polyurethane foaming chemical is introduced between the test piece in the jig and the metal plate to fill this space with the polyurethane foaming chemical, and the thermoplastic resin composite 1 / polyurethane foam layer 6 as shown in FIG. / Composite structure 9 consisting of metal plate 7 was manufactured, and urethane adhesion, CFC resistance, CFC resistance resistance, and thermoformability were tested according to Example 1. Table 1 shows the results.

Comparative Example 1 High-impact polystyrene (Dialex HT-516 manufactured by Mitsubishi Chemical Co., Ltd.) was extruded under the same conditions as in Example 1 to form a sheet having a total thickness of 2.0 mm. The CFC resistance, alternative CFC resistance, and thermoformability were evaluated according to Example 1. Table 1 shows the results.

Comparative Example 2 A polypropylene resin (Mitsubishi Polypro EC9) was used in Example 1
The sheet was extruded under the same conditions as described above to form a sheet having a total thickness of 2.0 mm, and urethane adhesion, chlorofluorocarbon resistance, alternative chlorofluorocarbon resistance, and thermoformability were evaluated according to Example 1. Table 1 shows the results.

Comparative Example 3 Acrylonitrile / butadiene / styrene copolymer (Taflex YT-197 manufactured by Mitsubishi Chemical Corporation) was used in Example 1.
The sheet was extruded under the same conditions as described above to form a sheet having a total thickness of 2.0 mm, and urethane adhesion, chlorofluorocarbon resistance, alternative chlorofluorocarbon resistance, and thermoformability were evaluated according to Example 1. Table 1 shows the results.

Comparative Example 4 A polypropylene resin containing a filler (Mitsubishi Polypro TX1088 manufactured by Mitsubishi Chemical Co., Ltd.) was extruded under the same conditions as in Example 1 to form a sheet having a total thickness of 2.0 mm, and urethane adhesion and CFC resistance. Further, the evaluation of the alternative CFC resistance and thermoformability was carried out according to Example 1. Table 1 shows the results.

Comparative Example 5 In Example 1, sheet formation was carried out by coextruding and laminating in the same manner as in Example 1 except that only the polyester resin was used as the composite layer 4, urethane adhesion, flon resistance and Evaluation of alternative CFC resistance and thermoformability was carried out. Table 1 shows the results.

[0046]

[Table 1]

[0047]

EFFECTS OF THE INVENTION The thermoplastic resin composite of the present invention is resistant to freon and alternative freon (resistant to swelling, cracking, crazing, etc.) and has good thermoformability. Is. Therefore, such a thermoplastic resin composite can be suitably used as a laminate for a heat insulating material such as a liner for a refrigerator.

[Brief description of drawings]

FIG. 1 is a sectional view of a thermoplastic resin composite having a three-layer structure according to an embodiment of the present invention.

FIG. 2 is a sectional view of a thermoplastic resin composite having a four-layer structure according to an embodiment of the present invention.

FIG. 3 is a sectional view of a thermoplastic resin composite having a five-layer structure according to an example of the present invention.

FIG. 4 is a sectional view of a thermoplastic resin composite having a seven-layer structure according to an example of the present invention.

FIG. 5 is a cross-sectional view of a refrigerator liner in which a polyurethane foam material layer and a metal cabinet layer are laminated on the thermoplastic resin composite having the three-layer structure of FIG.

FIG. 6 is a cross-sectional view of a composite structure in which a polyurethane foam layer is sandwiched by the thermoplastic resin composite having the three-layer structure of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thermoplastic resin composite 2 Thermoplastic resin layer 3 Adhesive thermoplastic resin layer 4 Composite layer, Freon barrier resin layer 4a Polyester resin layer 4b Ethylene / vinyl alcohol copolymer resin layer 5 Recycled resin 6 Polyurethane foam material layer 7 Metal Cabinet Layer 8 Composite Structure 9 Refrigerator Liner

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location B32B 27/36 B32B 27/36 27/40 27/40 (72) Inventor Jun Maeda Yokkaichi, Mie Prefecture City Toho-cho 1-shi, Mitsubishi Chemical Co., Ltd. Yokkaichi Research Institute (72) Inventor Hitoshi Yamada 1 Toho-cho, Yokkaichi-shi, Mie Mitsubishi Chemical Co., Ltd. Yokkaichi Research Institute (72) Inventor Shiro Ueki Tokyo 1-12 Ueno, Taito-ku Kodama Chemical Industry Co., Ltd.

Claims (4)

[Claims] 1. A thermoplastic resin layer comprising a polyester resin layer and an ethylene / vinyl alcohol copolymer resin layer laminated on the thermoplastic resin layer via an adhesive thermoplastic resin layer. Resin composite. 2. The thermoplastic resin composite according to claim 1, wherein the adhesive thermoplastic resin layer is a thermoplastic resin modified with a polar compound. 3. The thermoplastic resin composite according to claim 1, wherein a polyurethane foam material layer is laminated on the composite layer side comprising a polyester resin layer and an ethylene / vinyl alcohol copolymer resin layer. 4. The thermoplastic resin composite according to claim 3, further comprising a metal cabinet layer laminated on the polyurethane foam material layer side.