JP4939496B2 - Polystyrene resin laminated foam sheet, method for producing the same, and polystyrene resin laminated foam container - Google Patents

Description

  The present invention relates to a polystyrene-based resin laminated foam sheet suitable for food containers such as instant noodles in cups, and more particularly, when formed into a container, the generation of bubbles can be reduced, and the gloss of the polyolefin-based resin layer on the inner surface of the container The present invention relates to a polystyrene resin laminated foam sheet having a reduced degree, a method for producing the same, and a polystyrene resin laminated foam container (hereinafter abbreviated as a container) obtained by thermoforming the sheet.

Polystyrene resin foam sheets have a beautiful surface, are lightweight yet strong, have excellent moldability, are inexpensive, are hydrophobic, hygienic, and have excellent heat and heat insulation properties. It is shaped into a shape, cup shape, and bowl shape, and is widely used as various food packaging materials and simple containers. In the molding, a polystyrene resin foam sheet having a specific primary thickness is heated, and the resin is softened and foamed by the action of a foaming agent such as butane contained in the foam sheet to increase the thickness (this is increased by two). (Referred to as next foaming), press molding, vacuum molding, match mold molding, and the like, and continuous molding into a predetermined container shape.
These containers are mainly used for instant noodles in cups typified by instant noodles, but inside these containers are packs of ingredients filled and sealed in various packaging bags in addition to dry noodles. . If these ingredients are placed in a container without being put in a packaging bag, the dried ingredients will absorb moisture, leading to a decrease in quality, shortening the storage period, and damaging the ingredients themselves. It was necessary to improve the performance. In order to improve the moisture resistance of the polystyrene resin foam container, it is conceivable to form the container using a laminated sheet in which a polyolefin resin film is laminated on the inner surface of the container.
Conventionally, for example, the techniques disclosed in Patent Documents 1 to 3 have been proposed regarding a laminated foam sheet obtained by laminating a polystyrene resin foam sheet and a polyolefin resin film and a container obtained by thermoforming the sheet. ing.

  Patent Document 1 discloses a food container made of a foamed resin obtained by laminating a foamed polystyrene layer rich in heat insulation and a foamed polypropylene layer rich in heat resistance, and the foamed polypropylene layer is laminated inside the foamed polystyrene layer. A foamed polypropylene laminated container characterized by comprising a container wall is disclosed.

  Patent Document 2 discloses a multilayer in which a surface layer made of polyethylene terephthalate (PET) is integrally laminated on one or both sides of a base material layer made of expanded polystyrene via an adhesive layer containing a styrene / butadiene / styrene copolymer. A food container is disclosed in which a resin sheet is formed such that a surface layer made of the above-mentioned polyethylene terephthalate is disposed inside the container.

In Patent Document 3, a polystyrene-based resin non-foamed film (B) having a thickness of 25 to 200 μm is laminated on at least one surface of a polystyrene-based resin foamed sheet (A), and the other polystyrene-based resin non-foamed film is further laminated. On the surface of (B), a polystyrene-based resin laminated foam sheet in which a polyolefin-based non-foamed film (C) having a thickness of 10 to 100 μm was laminated was molded so that the polyolefin-based non-foamed film (C) surface was inside, A container characterized in that the elution amount of styrene dimer and styrene trimer in heptane is 100 ppb or less is disclosed.
JP 2000-190939 A Japanese Patent Laid-Open No. 2001-2134 JP 2003-53911 A

However, the above-described conventional technique has the following problems.
The prior art disclosed in Patent Document 1 is a laminated material of a foamed polystyrene sheet and a foamed polypropylene sheet. The adhesion between these different types of sheets is also described in, for example, paragraph numbers 0009 to 0010 of Patent Document 2. As described above, there is a problem in adhesion, and when a container is manufactured by thermoforming this laminated material, a float called “bubble” occurs between the polystyrene sheet and the polypropylene sheet, and a beautiful container is obtained. There was a problem that I could not.

  In the prior art disclosed in Patent Document 2, a PET film is laminated via an adhesive layer. However, a general PET film has a large difference in melt softening temperature from polystyrene, and cracks occur during molding. And the polystyrene foam layer overheated. For this reason, a special PET film having a low melting point has to be used, and there is a great problem in terms of cost.

The prior art disclosed in Patent Document 3 reduces oligomer elution against piercing and cracking by laminating a polyolefin resin film as the inner surface, but the adhesion method has not been studied and the adhesiveness is improved. There were difficulties, bubbles were generated between the polystyrene layer and the resin film during molding, and it was difficult to obtain a good-looking product.
In particular, when a foamed sheet or film having a low molecular weight component containing styrene dimer or styrene trimer is used, there is a problem that the adhesiveness is further lowered and the above phenomenon becomes remarkable.

In addition, in these conventional technologies, the glossiness of the inner surface of the container obtained by thermoforming the laminated foam sheet becomes too high, causing malfunction during inspection of the inner surface of the container, etc. There was a problem that it looked like this and the impression was bad.
That is, when adhering a foam sheet and a polyolefin film, softening of the resin is promoted by adhering at a high temperature, and the smoothness of the polyolefin film surface is further improved in the cooling roll immediately after the hot roll, so that the polyolefin film side The glossiness of the surface will increase. The container obtained by thermoforming the laminated sheet has a high glossiness of the surface of the polyolefin layer on the inner surface side of the container, and in recent years, a device that inspects an object such as a container with a CCD camera under the mainstream illumination. There was a problem that would cause malfunction due to diffuse reflection. Further, when the consumer visually observes the inner surface of the container, if the gloss on the inner surface of the container is high, there is a problem that the oil appears to be attached and the impression of the product is deteriorated.

  The present invention has been made in view of the above circumstances, and when molded into a container, a polystyrene-based resin laminated foam sheet that can reduce bubble generation and reduce the glossiness of the polyolefin-based resin layer on the inner surface of the container, and the sheet It aims at providing the container obtained by thermoforming.

In order to achieve the above object, the present invention provides a polystyrene resin film (2) having a thickness in the range of 5 μm to 24 μm on one surface of the polystyrene resin foam sheet (1), an adhesive layer (3), A polyolefin resin film (4) having a thickness in the range of 5 μm to 50 μm is laminated in order,
The adhesive strength between the polystyrene resin film (2) and the polyolefin resin film (4) is 500 gf or more, and the adhesive strength between the polystyrene resin foam sheet (1) and the polystyrene resin film (2). Is 650 gf or more,
And the glossiness of the surface of the said polyolefin resin film (4) side is 75% GL or less, The polystyrene resin laminated foam sheet (5) characterized by the above-mentioned is provided.

  In the polystyrene resin laminated foam sheet of the present invention, a polystyrene resin non-foamed film (6) having a thickness in the range of 40 μm to 250 μm is laminated on the other surface of the polystyrene resin foam sheet (1). preferable.

  In the polystyrene resin laminated foam sheet of the present invention, the polyolefin resin film (4) is preferably a polypropylene resin film.

  In the polystyrene resin laminated foam sheet of the present invention, the adhesive layer (3) is an adhesive selected from a polyurethane adhesive, a polyester adhesive, a polyether adhesive, an acrylic adhesive, and a vinyl acetate adhesive. It is preferable to consist of an agent.

  Moreover, this invention provides the container obtained by thermoforming the polystyrene-type resin laminated foam sheet which concerns on this invention mentioned above so that the inner side may become the said polyolefin-type resin film (4).

  In the container of the present invention, the glossiness of the inner surface of the container is preferably 65% GL or less.

In the container of the present invention, the moisture permeability of the container is preferably 630 g / m ² · 30 days or less.

The present invention also includes a polystyrene resin foam sheet (1), a polystyrene resin film (2) having a thickness in the range of 5 μm to 24 μm, and a polyolefin resin film (4) having a thickness in the range of 5 μm to 50 μm. Prepare a polyolefin-based resin laminated film (7) bonded through an adhesive layer (3),
The roll temperature is in the range of 180 to 210 ° C. in a state where the polystyrene resin film (2) side of the polyolefin resin laminated film (7) is superposed on one surface of the polystyrene resin foam sheet (1). The polystyrene-based resin foamed sheet (1) and the polystyrene-based resin film (2) are adhered to each other through a heat roll, and the polystyrene-based resin laminated foamed sheet (5) according to any one of claims 1 to 4 is used. A method for producing a polystyrene-based resin laminated foam sheet is provided.

  In the method for producing a polystyrene-based resin laminated foam sheet of the present invention, as the polystyrene-based resin foam sheet (1), a polystyrene-based resin having a thickness in the range of 40 μm to 250 μm is formed on the other surface of the polystyrene-based resin foam sheet (1). It is preferable to use a film-laminated foam sheet (8) formed by laminating a resin non-foamed film (6).

  In the method for producing a polystyrene resin laminated foam sheet of the present invention, immediately after the polystyrene resin foam sheet (1) and the polystyrene resin film (2) are bonded through the hot roll, the roll temperature is 40 ° C. or less. It is preferable to cool the polystyrene-based resin laminated foam sheet (5) through the cooling roll.

The polystyrene resin laminated foam sheet (5) of the present invention has a polystyrene resin film (2) having a thickness in the range of 5 μm to 24 μm on one surface of the polystyrene resin foam sheet (1) and an adhesive layer (3 ) And a polyolefin resin film (4) having a thickness in the range of 5 μm to 50 μm in order, and the adhesive strength between the polystyrene resin film (2) and the polyolefin resin film (4) is 500 gf or more. In addition, the adhesive strength between the polystyrene resin foam sheet (1) and the polystyrene resin film (2) is 650 gf or more, and the glossiness of the surface on the polyolefin resin film (4) side is 75% GL or less. Since it is a thing, the adhesive strength between the polystyrene-based resin foam sheet (1) and the polyolefin-based resin film (4) is increased. When manufacturing the container a foam sheet and thermoforming, it prevents the bubble generated in the resultant containers can look to produce a good beautiful container.
Further, since the glossiness of the surface on the polyolefin resin film (4) side is 75% GL or less, containers obtained by thermoforming such that the polyolefin resin film (4) side is on the inside are mainly used in recent years. By using a device that inspects with a CCD camera under illumination, it is difficult to cause malfunction due to irregular reflection, and the gloss on the inside of the container is reduced, so that the appearance of oil adhesion can be prevented.

Since the container of the present invention is obtained by thermoforming the above-described polystyrene-based resin laminated foam sheet according to the present invention so that the inside thereof becomes the polyolefin-based resin film (4), it has excellent moisture resistance. The container is less likely to be peeled off between the layers.
In addition, the adhesive strength between the polystyrene-based resin foam sheet (1) and the polyolefin-based resin film (4) on the inner surface side of the container is increased, and no bubbles are generated on the inner surface side of the container, providing a beautiful and beautiful container. it can.
Furthermore, since the glossiness on the inside of the container is lowered, it becomes difficult to cause malfunction due to irregular reflection by an apparatus that inspects with a CCD camera by applying illumination which has been mainly used in recent years, and can be surely inspected. In addition, the gloss on the inside of the container is reduced, and it is possible to prevent a problem that looks like oil adhesion.

  As described above, the method for producing a polystyrene-based resin laminated foam sheet of the present invention can reduce the generation of bubbles when molded into a container, and also reduces the glossiness of the polyolefin-based resin layer on the inner surface of the container. A laminated foam sheet can be produced efficiently.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a view showing an embodiment of a polystyrene resin laminated foam sheet according to the present invention. In this figure, reference numeral 1 is a polystyrene resin foam sheet, 2 is a polystyrene resin film, 3 is an adhesive layer, 4 Is a polyolefin resin film, 5 is a polystyrene resin laminated foam sheet, 6 is a polystyrene resin non-foamed film, 7 is a polyolefin resin laminated film, and 8 is a film laminated foam sheet.

  The polystyrene resin laminated foam sheet 5 of the present embodiment has a polystyrene resin film 2 having a thickness in the range of 5 μm to 24 μm, an adhesive layer 3 and a thickness of 5 μm on one surface of the polystyrene resin foam sheet 1. The polyolefin resin film 4 in the range of ˜50 μm is laminated in order, and the adhesive strength between the polystyrene resin film 2 and the polyolefin resin film 4 is 500 gf or more, and the polystyrene resin foam sheet 1 The adhesive strength with the polystyrene resin film 2 is 650 gf or more, and the glossiness of the surface on the polyolefin resin film 4 side is 75% GL or less.

  The polystyrene-based resin foam sheet 1 is obtained by supplying a raw polystyrene-based resin together with a foaming agent such as butane to an extruder, melt-kneading, and then extrusion-foaming. The expansion ratio and average thickness of the polystyrene-based resin foam sheet 1 are not particularly limited, but the expansion ratio is about 1.1 to 20 times, preferably about 2 to 15 times, and the average thickness is 0.6 to 3. It is about 0 mm, preferably about 1.5 mm to 2.5 mm.

  The raw material resin of the polystyrene-based resin foam sheet 1 is not particularly limited, and examples thereof include a styrene homopolymer or a copolymer containing 50% by mass or more of styrene. Examples of the copolymer include styrene-maleic anhydride, styrene-methacrylic acid, styrene-acrylic acid (including acrylic acid ester, etc.), copolymer resins such as styrene-acrylonitrile, and ternary copolymers such as acrylonitrile-butadiene-styrene. Polymerized resin etc. are mentioned. Examples of copolymer components in the copolymer include α-methyl styrene, ethyl styrene, isopropyl styrene, dimethyl styrene, paramethyl styrene, t-butyl styrene, chlorostyrene, bromostyrene, and other styrene derivatives, methyl acrylate, and butyl acrylate. And esters of acrylic acid and methacrylic acid such as methyl methacrylate, ethyl methacrylate, and cetyl methacrylate, or various monomers such as acrylonitrile, dimethyl fumarate, ethyl fumarate, vinyl toluene, vinyl xylene, butadiene, and maleic anhydride. . In the raw material resin, other resins (for example, a polyethylene resin, a polypropylene resin, etc.) can be appropriately mixed within a range not impairing the effects of the present invention. Further, as the raw material resin, it is preferable to use a resin in which a low molecular weight component including styrene dimer and styrene trimer is reduced since the elution of the low molecular weight component can be reduced.

  In order to improve the strength and printability of the polystyrene resin laminated foam sheet 5 of this embodiment, a polystyrene resin non-foamed film having a thickness in the range of 40 μm to 250 μm is formed on the other surface of the polystyrene resin foam sheet 1. 6 are stacked. As the raw material resin of the polystyrene-based resin non-foamed film 6, the same resin as the raw material resin of the polystyrene-based resin foamed sheet 1 described above can be used. In particular, the polystyrene resin contains a rubber component and is brittle. A high impact polystyrene resin film having an improvement effect is preferred. Moreover, as a raw material of this polystyrene-type resin non-foamed film 6, it is preferable to use a resin in which a low molecular weight component including styrene dimer and styrene trimer is reduced because elution of the low molecular weight component can be reduced.

  The polystyrene resin film 2 adhered to one surface of the polystyrene resin foam sheet 1 is a polystyrene that can be firmly adhered when the surface of the polystyrene resin foam sheet 1 is adhered to the surface of the polystyrene resin foam sheet 1 by a hot roll. A resin film is used. As the raw material resin of the polystyrene resin film 2, the same material resin as that of the polystyrene resin foam sheet 1 described above can be used. The thickness of the polystyrene resin film 2 is in the range of 5 μm to 24 μm, preferably in the range of 10 μm to 20 μm. If the thickness of the polystyrene-based resin film 2 is less than 5 μm, the strength of the film is weakened, and there is a risk that the film will be cut or wrinkled easily in the laminating process. On the other hand, if the thickness exceeds 24 μm, the thickness of the film becomes thick and heat is not easily transmitted when bonding with a hot roll, and the adhesiveness may be lowered.

  The adhesive 3 is preferably a polyurethane adhesive, a polyester adhesive, a polyether adhesive, an acrylic adhesive, or a vinyl acetate adhesive, and more preferably a polyurethane adhesive or a polyester adhesive.

  Examples of the polyolefin resin film 4 include polyethylene resins and polypropylene resins, and polypropylene resins are particularly preferable. The polyolefin resin film 4 has a thickness in the range of 5 μm to 50 μm, preferably in the range of 15 μm to 35 μm. If the thickness of the polyolefin resin film 4 is less than 5 μm, the strength of the film is weakened, and there is a possibility that the film will be cut or wrinkled easily in the lamination process. On the other hand, if the thickness exceeds 50 μm, the thickness of the film becomes thick and heat is not easily transmitted when bonding with a hot roll, and the adhesiveness may be lowered.

In the polystyrene-based resin laminated foamed sheet 5 of the present embodiment, the adhesive strength between the polystyrene-based resin film 2 and the polyolefin-based resin film 4 (hereinafter referred to as the adhesive strength between layers (2) / (4)) is 500 gf or more. The adhesive strength between the polystyrene resin foam sheet 1 and the polystyrene resin film 2 (hereinafter referred to as the adhesive strength between layers (1) / (2)) is preferably 650 gf or more, preferably 600 gf or more. It is 750 gf or more.
The adhesive strength between the layers (2) / (4) is the adhesive strength between the layers obtained by adhering the polystyrene resin film 2 and the polyolefin resin film 4 with the adhesive 3, and the layer (1) / (2) indirectly. The adhesion strength is determined by superimposing the film-laminated foam sheet 8 and the polyolefin-based resin laminate film 7 on the surface of the polystyrene resin-laminated foam sheet 5 and bonding them through a hot roll. It is the adhesive strength of the part which the polystyrene-type resin film 2 adhere | attached.
When the adhesive strength between layers (2) / (4) is less than 500 gf, when packaging food such as instant noodles in cups using a container obtained by thermoforming the polystyrene-based resin laminated foam sheet 5, When the consumer peels off the lid of the product, the layers (2) / (4) are separated, and there is a possibility that the polyolefin resin film 4 on the inner surface side of the container is peeled off.
If the adhesive strength between the layers (1) / (2) is less than 650 gf, there is a possibility that blister-like film floating (peeling) called so-called bubbles occurs when the container is thermoformed.

Moreover, in the polystyrene-type resin laminated foam sheet 5 of this embodiment, the glossiness of the surface by the side of the said polyolefin-type resin film 4 is 75% GL or less, Preferably it is 70% GL or less.
When this glossiness exceeds 75% GL, when this polystyrene-based resin laminated foam sheet 5 is molded so that the polyolefin-based resin film 4 side is on the inside, a glossiness inside the obtained container is obtained. However, a device that inspects with a CCD camera or the like tends to cause malfunction due to irregular reflection, and the gloss on the inside of the container looks like oil adhesion, which may cause discomfort to the consumer.

The polystyrene-based resin laminated foam sheet 5 of the present embodiment can be manufactured, for example, by the following manufacturing method.
First, a film laminated foamed sheet 8 in which a polystyrene resin non-foamed film 6 having a thickness in the range of 40 μm to 250 μm is laminated on the other surface of the polystyrene resin foamed sheet 1, and a thickness in the range of 5 μm to 24 μm. A polyolefin-based resin laminated film 7 is prepared by bonding a polystyrene-based resin film 2 and a polyolefin-based resin film 4 having a thickness in the range of 5 μm to 50 μm via an adhesive layer 3.

  The polystyrene-based resin foam sheet 1 of the film-laminated foam sheet 8 can be manufactured by extruding and foaming a raw material polystyrene-based resin by a known extrusion foaming method. The extrusion foaming method is performed by putting a raw material resin, a foaming agent and other additives into an extruder so as to obtain a desired density, melt-kneading, and then extruding from an extruder die. In addition, what mixed raw material resin, a foaming agent, and the additive uniformly previously may be supplied to an extruder. Further, the additive may be a so-called master batch product that is added in advance to the same type of resin as the raw material resin in a high concentration.

  Examples of the extruder used in the method of the present invention include known ones such as a single screw extruder and a twin screw extruder. Among them, a single screw extruder which is excellent in that it has low extrusion stability under high pressure and little thermal deterioration is preferable. Examples of the foaming agent used in the method of the present invention include known ones such as a decomposable foaming agent, a gas or a volatile foaming agent.

  Examples of the decomposable foaming agent include inorganic decomposable foaming agents such as ammonium carbonate, sodium bicarbonate, ammonium bicarbonate, ammonium nitrite, calcium azide, sodium azide, sodium borohydride, azodicarbonamide, azobissulfuramide, Azo compounds such as azobisisobutyronitrile and diazoaminobenzene, nitroso compounds such as N, N′-dinitrosopentanemethylenetetramine and N, N′-dimethyl-N, N′-dinitrosotephthalamide, benzenesulfonyl hydrazide , P-toluenesulfonyl hydrazide and p, p′-oxybisbenzenesulfonyl semicarbazide, p-toluenesulfonyl semicarbazide, trihydrazinotriazine, barium azodicarboxylate, citric acid, etc. It is.

  Examples of gaseous blowing agents include nitrogen, carbon dioxide, propane, n-butane, i-butane, tert-butane, dimethyl ether, and the like. In addition, gas means that it is gas at normal temperature (20 degreeC) and a normal pressure (1 atmosphere). Examples of the volatile blowing agent include ether, petroleum ether, acetone, pentane, isopentane, hexane, isohexane, heptane, isoheptane, benzene, toluene and the like. Water can also be used as a blowing agent. These foaming agents may be used alone or in combination of two or more.

  Among these blowing agents, n-butane and i-butane are particularly preferable. When the cell size of the polystyrene resin foam sheet 1 is about 40 μm or less, it is preferable to use nitrogen, carbon dioxide gas or water as the foaming agent. In particular, nitrogen and carbon dioxide are preferable in that they are inexpensive. The addition amount of the foaming agent is about 0.25 to 5.0 parts by mass with respect to 100 parts by mass of the base resin.

  Moreover, in manufacture of the polystyrene-type resin foam sheet 1, you may add a bubble regulator etc. to raw material resin. Examples of the bubble regulator include inorganic powders such as talc and silica, acidic salts such as polyvalent carboxylic acids, and reaction mixtures of polyvalent carboxylic acids with sodium carbonate or sodium bicarbonate. The amount of the bubble regulator added is about 0.01 to 6.0 parts by mass with respect to 100 parts by mass of the raw material resin. When the amount of the air bubble regulator increases, the cell membrane becomes weak against heat, and the cell membrane may be broken during extrusion lamination, resulting in an increase in cell size. In order to prevent such an increase in bubbles, it is preferable to use nitrogen or carbon dioxide as a foaming agent.

  In the production of the polystyrene-based resin foam sheet 1, an ultraviolet absorber, an antioxidant, a colorant, a lubricant, a flame retardant, an antistatic agent, and the like may be added to the raw material resin as desired. The melt-kneaded resin is extruded and foamed from a die adjusted to a temperature suitable for foaming to obtain a foam. This foam can be made into a sheet by directly extruding it into a sheet or once into a cylinder and then cutting it along an arbitrary line.

The extruder barrel temperature when producing the polystyrene-based resin foamed sheet 1 varies depending on the type of the extruder used and the raw material resin, but is preferably about 140 to 260 ° C. In order to laminate the polystyrene resin non-foamed film 6 on the other surface of the polystyrene resin foam sheet 1, a method of laminating the foam sheet and the film together, a heating roll, an adhesive, or the like is used. The method of laminating a film is mentioned.
In particular,
(A) A coextrusion method in which a foam sheet and a film are merged and laminated and then extruded from a die.
(B) A method of directly laminating the foamed sheet in an inline or outline before the film extruded from the extruder is completely cooled,
(C) A method of laminating a film (which may be plain or printed) on a foamed sheet with a resin extruded from an extruder as a binder inline or outline,
(D) A method of pressing and laminating a film (which may be plain or printed) on a foam sheet while heating with a heating roll, and the like.

  Moreover, in order to manufacture the polyolefin resin laminated film 7, a dry laminating apparatus is used, and after applying a solvent-based adhesive to the polyolefin resin film 4, an unnecessary solvent component is removed through a drying furnace to form the adhesive layer 3. A method of bonding the polystyrene-based resin film 2 and the polyolefin-based resin film 4 via the adhesive layer 3 by forming and press-bonding the adhesive layer 3 and the polystyrene-based resin film 2 in a superimposed state is preferable.

  Next, in a state where the polystyrene resin film 2 side of the polyolefin resin laminated film 7 is superimposed on one surface of the polystyrene resin foam sheet 1, a hot roll having a roll temperature in the range of 180 to 210 ° C. is passed, The polystyrene-based resin foamed sheet 1 and the polystyrene-based resin film 2 are adhered to each other to produce a polystyrene-based resin laminated foamed sheet 5 having a structure shown in FIG.

  The container according to the present invention is obtained by thermoforming the polystyrene-based resin laminated foamed sheet 5 manufactured as described above so that the inside thereof becomes the polyolefin-based resin film 4. As a method for thermoforming the polystyrene-based resin laminated foamed sheet 5, for example, after softening the foam in an oven (temperature 230 to 300 ° C.), heating is performed using a desired mold for 3 to 20 seconds. The method of shaping | molding is mentioned.

The shape and dimensions of the container according to the present invention are not particularly limited, and examples include cups and bowls for instant noodles with cups.
The container according to the present invention preferably has a gloss of 65% GL or less on the inner surface of the container. When the glossiness of the inner surface of the container exceeds 65% GL, it becomes easy to cause malfunction due to irregular reflection by a device that inspects with a CCD camera, etc. Also, the gloss on the inner side of the container looks like oil adhesion, so it is uncomfortable for consumers. There is a risk of giving.

The container according to the present invention preferably has a moisture permeability of 630 g / m ² · 30 days or less. If the moisture permeability is 630 g / m ² · 30 days or less, it is possible to effectively prevent moisture from entering the container, so the drying tool material can be directly put into the container without putting it in the inner bag made of resin film. Even if it is filled, the dry state of the ingredients can be kept good. Further, if the moisture permeability exceeds 630 g / m ² · 30 days, it is necessary to put the ingredients in an inner bag made of a resin film in order to keep the drying ingredient dry.

Another embodiment of the present invention will be described.
(A) When the adhesive strength between the polystyrene-based resin film 2 and the polyolefin-based resin film 4 is measured, the strength difference between the maximum point and the minimum point in the peeling section is preferably 100 gf or less. If this strength difference is 100 gf or less, even if a peeling action due to a sudden force occurs, delamination hardly occurs.

(B) When the film-laminated foam sheet 8 and the polyolefin-based resin laminated film 7 are bonded with a hot roll, bonding at a high temperature (although depending on the roll speed, usually around 220 ° C.) is not preferable, and a lower temperature. It is preferable to improve the adhesion. In the case of high-temperature bonding, the adhesion is improved, but the surface gloss of the polyolefin resin on the inner surface of the container is increased, and the inspection device used causes malfunction due to irregular reflection in the inspection with the CCD camera on the inner surface of the container It becomes. In order to satisfy both sufficient adhesiveness and moderate glossiness, it is preferable to set the hot roll temperature in the range of 180 ° C. to 200 ° C. and cool the sheet immediately after the hot roll.

(C) When adhering the film-laminated foam sheet 8 and the polyolefin-based resin laminated film 7 with a hot roll, it is preferably cooled with a metal roll having a surface temperature of 25 ° C. to 35 ° C. after passing through the hot roll. By this method, over-foaming of the obtained polystyrene-based resin laminated foamed sheet 5 is prevented, and warpage of the sheet itself due to shrinkage of the polyolefin-based resin film 4 can be reduced.

(D) The lower limit of the gloss on the inner surface of the container is not particularly specified, but it is desirable that the gloss of the polyolefin resin film 4 itself before adhesion is low. From such a viewpoint, for example, in a polypropylene resin film, it is generally preferable to use an unstretched film (CPP film) rather than a stretched film (OPP film). The glossiness of a general CPP film is around 100% GL, and the glossiness is likely to decrease due to lamination conditions.

(E) The styrene dimer and trimer content in the polystyrene resin film 2 is more preferably 1400 ppm or less, and the elution value of the styrene dimer and trimer in the obtained container is more preferably 50 ppb or less.

[Example 1]
(Method for producing polystyrene-based resin foam sheet 1 and film-laminated foam sheet 8)
As the polystyrene-based resin foam sheet 1, a foam sheet obtained by an extrusion foaming method was used.
Polystyrene resin (product name: HRM-52 (manufactured by Toyo Styrene Co., Ltd., MI = 2.2), 100 parts by mass of butane gas (isobutane / normal butane = 65/35) as a foaming agent, 3.8 parts by mass, bubble regulator As a master batch product containing 0.85 parts by mass of powder talc (DSM-1401A (manufactured by Toyo Styrene Co., Ltd.)), a maximum temperature of 260 ° C. is used using a tandem extruder in which an extruder having a diameter of 115 mmφ and 180 mmφ is connected. The raw material resin was melted and kneaded in an extruder set to 1, and then cooled and adjusted to a resin temperature of 153 ° C., and foamed and extruded from a circular die having a diameter of 170 mm (clearance 0.6 mm).
0.13 m ³ / ^{m 2} the air 35 ° C. inside immediately after the extrusion, spraying at a rate of 0.30 m ³ / ^{m 2} on the outside, a thickness of 2.0 mm, magnification 9.2 times the polystyrene-based resin foam sheet Got. The obtained cyclic foamed sheet was passed through a cooling mandrel having a diameter of 671 mm, cut into two sheets with a cutter, and wound into a roll to obtain a polystyrene-based resin foamed sheet 1.
After replacement for foaming gas, after storing for 14 days, a high impact polystyrene resin film was laminated on the surface of the polystyrene resin foam sheet 1. In this lamination process, a high impact polystyrene resin (product name: E-640N (manufactured by Toyo Styrene Co., Ltd.)) is melted with a 120 mmφ extruder set at a maximum temperature of 240 ° C., extruded in a film form from a T die, and cannot be cooled completely. The film was laminated on the surface of the polystyrene-based resin foam sheet so as to have a thickness of 100 μm and adhered through a roll to obtain a film-laminated foam sheet. Furthermore, immediately before winding up the sheet, silicone oil was sprayed using a silicone coating apparatus (Nikka Co., Ltd.) to obtain a final film laminated foam sheet 8.

(Polyolefin resin laminated film 7)
30 μm unstretched polypropylene film AT (manufactured by Osaka Resin Chemical Co., Ltd.) and 20 μm polystyrene resin film made from HRM-52 (manufactured by Toyo Styrene Co., Ltd., styrene dimer, trimer content 1200 ppm) as a raw material, TM329 of polyurethane adhesive (Toyo Morton Co., Ltd.) was adhered as an adhesive layer to obtain a polyolefin-based resin laminated film 7.

(Manufacture of polystyrene resin laminated foam sheet)
The surface of the film-laminated foamed sheet 8 (the surface on the side of the polystyrene-based resin foamed sheet 1) is overlapped with the polystyrene-based resin film side of the polyolefin-based resin-laminated film 7 and passed through a pair of hot rolls having a diameter of 250 mmφ. A hot roll process was performed under conditions of a roll temperature of 195 ° C. and a take-off speed of 9.0 m / min, and immediately after that, a cooling roll having a surface temperature of 25 ° C. was passed through and cooled to obtain a polystyrene-based resin laminated foam sheet 5.

(Manufacture of containers)
Using the polystyrene-based resin laminated foam sheet 5 produced as described above, molding was performed so that the polyolefin-based resin film was on the inside. Molding conditions were as follows: furnace atmosphere temperature was 160 ° C. and molding time was 13 to 15 seconds, followed by thermoforming using a mold for manufacturing a round container having a diameter of 110 mm × depth of 60 mm.

  For the polystyrene-based resin laminated foam sheet 5 and container produced as described above, according to the measurement method and judgment criteria described later, adhesive strength, glossiness, elution amount of styrene dimer / trimer, moisture permeability, container appearance, lid peeling, container Measurement and evaluation were performed for each of the test items of evaluation and overall evaluation of the appearance of the inner surface.

<Measurement method of adhesive strength>
Measured by cutting a measurement sample to a width of 15 mm and a length of 200 mm, using Tensilon RTM-500 manufactured by Orientec Corporation, and pulling the ends of each layer to each other in a 90 ° direction at a speed of 200 mm per minute. In the 80 mm peeling section, the first and last 20 mm were respectively passed, and the integrated average load (gf) in the section of 20 mm to 60 mm from the start of peeling was used as the peeling data of the measurement sample. By this method, the number of measurement samples (N) = 5 was measured in the sheet width direction, and the average value was defined as the adhesive strength (gf).
In this example, the adhesive strength between layers (1) / (2) and the adhesive strength between layers (2) / (4) of the produced polystyrene-based resin laminated foamed sheet 5 were measured. Also, the adhesive strength between the layers (1) / (2) or the adhesive strength between the layers (2) / (4) is very high, and any one of the layers (1), (2), (4) is not peeled off. When it was destroyed, “material destruction” was displayed.

<Glossiness measurement method>
JIS K7105: Measured by the method described in “Testing method for optical properties of plastic”. That is, using a handy gloss meter Gloss Checker IG-320 (Horiba Seisakusho Co., Ltd.), measure the surface of the measurement sample (the surface on the polyolefin resin film side) at 5 points in the width direction with a 60-degree meter (incident angle 60 degrees). The average value was defined as the glossiness.
In this Example, the glossiness of the polyolefin resin film side surface (glossiness of sheet properties) and the glossiness of the inner surface of the container (glossiness of container properties) of the produced polystyrene resin laminated foam sheet 5 Each was measured.

<Measurement method of elution amount of styrene dimer / trimer>
(1) Preparation of eluate After 570 mL of double-distilled heptane (distilled twice in order to recycle the heptane used for elution) was used as the elution solvent in the sample vessel, and elution was performed at 25 ° C. for 1 hour. From this solution, 100 ml was collected, concentrated to 1 mL at 50 ° C. using a fully automatic concentrator (Zymark, Turbobop 500), and 40 μL of internal standard solution (pyrene 100 μg / mL) was added immediately before the measurement. The test solution was made up to 2 mL with n-heptane.
(2) GCMS analysis GCMS analysis is performed under the following conditions, and quantified by using a calibration curve of styrene oligomer prepared in advance using the peak area of 4 dimer peaks and 6 trimer peaks in the chromatogram and the peak area of the internal standard substance. did. Calibration curves for dimers and trimers were prepared using standard materials manufactured by Kanto Chemical.
GCMS analysis condition device: GCMS QP5050 (manufactured by Shimadzu Corporation).
Column: DB-5 (manufactured by J & W) φ0.25 mm × 30 m × film thickness 0.25 μm.
Inlet temperature: 240 ° C.
Interface temperature: 260 ° C.
Carrier gas: helium (1.2 mL / min).
Test solution injection volume: 1 μL (using an autosampler).
Column temperature: 70 ° C. (1 min) to 15 ° C./min to 260 ° C. (0 min) to 10 ° C./min to 300 ° C. (3.0 min).

<Measurement method of moisture permeability>
It was measured by the method described in JIS Z0222. That is, 50 g of calcium chloride is put into a container 110 mm in diameter and 60 mm in depth obtained by thermoforming, and the same sealant as that used for general instant noodles in cups with extremely low moisture permeability is used as a lid. An attached aluminum seal lid (diameter: 110 mm) was used to cover the lid by heat compression, and paraffin melted to prevent leakage was applied to the cross section of the lid and the container to make it completely sealed. Thereafter, the sample was left in an environment of 40 ± 0.5 ° C. and a humidity of 90 ± 2% for 24 hours, and the moisture permeability was calculated from the increased mass. For the moisture permeability, the measured numerical value was converted to a mass that permeates moisture per 1 m ² in 30 days.

<Appearance evaluation of container>
The appearance of the obtained container was visually evaluated.
◯: Good without bubbles (peeling) on the inner surface of the container.
X: There is a float (peeling) such as a bubble on the inner surface of the container, which is defective.

<Measurement and evaluation of lid peeling>
A lid of 110 mm in diameter and 60 mm in depth obtained by thermoforming is heated and compressed using an aluminum seal lid (diameter 110 mm) with the same sealant as that used for general instant noodles with cups. And left at room temperature for a day. After leaving the container, the lid of the container was peeled off by hand, and the peeled state was visually observed and evaluated based on the following evaluation criteria.
○: Good with no abnormality in peeling between lid and container.
X: A part of the container is peeled off together while adhered to the lid side, resulting in a bag-like defect.

<Appearance evaluation of inner surface of container>
The appearance of the inner surface of the obtained container was visually evaluated.
○: Good because the inner surface of the container is not glossy and does not appear to have oil.
X: The inner surface of the container is glossy and appears to be oily, and is defective.

<Comprehensive evaluation>
For each test item described above, one satisfying the reference value or evaluation standard was evaluated as ◯: good, and at least one of the test items was evaluated as x: defective when the reference value or evaluation standard was not satisfied.

The polystyrene-based resin laminated foam sheet 5 and container of this example were measured and evaluated for each test item described above, and the results are shown in Table 1.
The polystyrene-based resin laminated foam sheet 5 and the container of this example both have high adhesive strength between layers (1) / (2) and adhesive strength between layers (2) / (4), and the surface on the polyolefin-based resin film side. The glossiness of became low.
The moisture permeability of the container was 375 (g / m ² · 30 days), which was below the reference value.
The elution amount of styrene dimer and trimer in the container was as low as 34 ppb.
The evaluation of the appearance of the container, the lid peeling, and the appearance of the inner surface of the container was also good.
As a result, the overall evaluation of this example was good: good.

[Example 2]
In advance, a 20 μm polystyrene resin film made of 30 μm unstretched polypropylene film E2C (manufactured by Tosero Co., Ltd.) and HRM-52 (manufactured by Toyo Styrene Co., Ltd.) was bonded as an adhesive layer with AD393 (manufactured by Toyo Morton Co., Ltd.) as a polyurethane adhesive. Except having used the polyolefin-type resin laminated film, the polystyrene-type resin laminated foam sheet was obtained with the manufacturing method similar to Example 1, and also the container was manufactured.
The polystyrene-based resin laminated foam sheet 5 and container of this example were measured and evaluated for the test items described above in the same manner as in Example 1, and the results are shown in Table 1.
The polystyrene-based resin laminated foam sheet 5 and the container of this example both have high adhesive strength between layers (1) / (2) and adhesive strength between layers (2) / (4), and the surface on the polyolefin-based resin film side. The glossiness of became low.
The moisture permeability of the container was 612 (g / m ² · 30 days), which was below the reference value.
The elution amount of styrene dimer and trimer in the container was a low level of 45 ppb.
The evaluation of the appearance of the container, the lid peeling, and the appearance of the inner surface of the container was also good.
As a result, the overall evaluation of this example was good: good.

[Example 3]
A 20 μm unstretched polypropylene film AT (manufactured by Osaka Resin Chemical Co., Ltd.) and HRM-52 (manufactured by Toyo Styrene Co., Ltd.) as a raw material and a polyurethane adhesive TM329 (manufactured by Toyo Morton Co., Ltd.) as an adhesive layer. A polystyrene resin laminated foam sheet was obtained by the same production method as in Example 1 except that the adhered polyolefin resin laminated film was used, and a container was further produced.
The polystyrene-based resin laminated foam sheet 5 and container of this example were measured and evaluated for the test items described above in the same manner as in Example 1, and the results are shown in Table 1.
The polystyrene-based resin laminated foam sheet 5 and the container of this example both have high adhesive strength between layers (1) / (2) and adhesive strength between layers (2) / (4), and the surface on the polyolefin-based resin film side. The glossiness of became low.
The moisture permeability of the container was 413 (g / m ² · 30 days), which was below the reference value.
The elution amount of styrene dimer and trimer in the container was a low level of 39 ppb.
The evaluation of the appearance of the container, the lid peeling, and the appearance of the inner surface of the container was also good.
As a result, the overall evaluation of this example was good: good.

[Example 4]
A 20 μm polystyrene resin film made from 30 μm unstretched polypropylene film AT (manufactured by Osaka Resin Chemical Co., Ltd.) and HRM-26 (manufactured by Toyo Styrene Co., Ltd.) (styrene dimer, trimer content 3750 ppm) as a raw material is AD585 (polyester adhesive) A polystyrene resin laminated foam sheet was obtained by the same production method as in Example 1 except that a polyolefin resin laminated film adhered with Toyo Morton Co., Ltd.) as an adhesive layer was used, and a container was further produced.
The polystyrene-based resin laminated foam sheet 5 and container of this example were measured and evaluated for the test items described above in the same manner as in Example 1, and the results are shown in Table 1.
The polystyrene-based resin laminated foam sheet 5 and the container of this example both have high adhesive strength between layers (1) / (2) and adhesive strength between layers (2) / (4), and the surface on the polyolefin-based resin film side. The glossiness of became low.
The moisture permeability of the container was 395 (g / m ² · 30 days), which was below the reference value.
The amount of styrene dimer and trimer eluted from the container was as low as 112 ppb.
The evaluation of the appearance of the container, the lid peeling, and the appearance of the inner surface of the container was also good.
As a result, the overall evaluation of this example was good: good.

[Comparative Example 1]
Polyolefin resin obtained by adhering a 20 μm polystyrene resin film made from 30 μm unstretched polypropylene film AT (manufactured by Osaka Resin Chemical Co., Ltd.) and HRM-52 (manufactured by Toyo Styrene Co., Ltd.) with AD585 (manufactured by Toyo Morton Co., Ltd.) as an adhesive layer. Except having used the laminated film, the polystyrene-type resin laminated foam sheet was obtained with the manufacturing method similar to Example 1, and also the container was manufactured.
The polystyrene-based resin laminated foam sheet and the container were measured and evaluated for each test item described above in the same manner as in Example 1, and the results are shown in Table 1.
Although this polystyrene-based resin laminated foam sheet had an adhesive strength between layers (1) / (2) of 865 gf, the adhesive strength between layers (2) / (4) was as low as 330 gf, and the polystyrene-based resin according to the present invention. It was below the lower limit (500 gf) of the adhesive strength between the layers (2) / (4) in the laminated foam sheet.
In addition, the container of this example had an evaluation of the appearance of the container and the appearance of the inner surface of the container: ◯: good, but the evaluation of lid peeling was x: poor.
When the elution amount of styrene dimer and trimer was measured in the obtained container, it was 53 ppb.
The moisture permeability was 415 (g / m ² · 30 days).
As a result of cutting out a part of the obtained container and measuring the glossiness, it was 55% GL.
As a comprehensive evaluation, the adhesive strength between the layers (2) / (4) was weak, and the polyolefin resin layer portion was peeled off in a bag shape in the evaluation of lid peeling, and x: poor.

[Comparative Example 2]
Adhesion layer of A969V (made by Mitsui Chemicals Polyurethane Co., Ltd.), a polyurethane adhesive, using a 20 μm polystyrene resin film made from 30 μm unstretched polypropylene film AT (made by Osaka Resin Chemical Co., Ltd.) and HRM-52 (made by Toyo Styrene Co., Ltd.) in advance. A polystyrene resin laminated foam sheet was obtained by the same production method as in Example 1 except that the polyolefin resin laminated film adhered as was used, and a container was further produced.
The polystyrene-based resin laminated foam sheet and the container were measured and evaluated for each test item described above in the same manner as in Example 1, and the results are shown in Table 1.
Although this polystyrene-based resin laminated foam sheet had an adhesive strength between layers (1) / (2) of 788 gf, the adhesive strength between layers (2) / (4) was as low as 250 gf, and the polystyrene-based resin according to the present invention. It was below the lower limit (500 gf) of the adhesive strength between the layers (2) / (4) in the laminated foam sheet.
In addition, the container of this example had an evaluation of the appearance of the container and the appearance of the inner surface of the container: ◯: good, but the evaluation of lid peeling was x: poor.
When the elution amount of styrene dimer and trimer was measured in the obtained container, it was 53 ppb.
The moisture permeability was 431 (g / m ² · 30 days).
As a result of cutting out a part of the obtained container and measuring the glossiness, it was 43% GL.
As a comprehensive evaluation, the adhesive strength between the layers (2) / (4) was weak, and the polyolefin resin layer portion was peeled off in a bag shape in the evaluation of lid peeling, and x: poor.

[Comparative Example 3]
As a heat laminating condition between the polyolefin resin laminated film and the polystyrene resin foamed sheet, a polystyrene resin laminated foamed sheet is obtained by the same production method as in Example 1 except that the heat roll temperature is 220 ° C. Manufactured.
The polystyrene-based resin laminated foam sheet and the container were measured and evaluated for each test item described above in the same manner as in Example 1, and the results are shown in Table 1.
This polystyrene-based resin laminated foam sheet had a high glossiness of 81% GL on the polyolefin resin film side and exceeded the upper limit (75% GL) of the glossiness of the polystyrene-based resin laminated foam sheet according to the present invention.
Also, the inner glossiness of the container was as high as 75% GL, and the appearance evaluation of the inner surface of the container was x: poor.
As a comprehensive evaluation, in the evaluation of the appearance of the inner surface of the container, it was poor because the inner surface of the container was glossy and oil was attached.

[Comparative Example 4]
Except that the take-up speed was 12.0 m / min as the thermal lamination condition between the polyolefin resin laminated film and the polystyrene resin foam sheet, a polystyrene resin laminate foam sheet was obtained by the same production method as in Example 1, and A container was manufactured.
The polystyrene-based resin laminated foam sheet and the container were measured and evaluated for each test item described above in the same manner as in Example 1, and the results are shown in Table 1.
This polystyrene-based resin laminated foam sheet has a low adhesive strength between layers (1) / (2) of 377 gf, and is weak enough that the adhesive strength between layers (2) / (4) cannot be measured. The interlayer adhesive strength in the polystyrene-based resin laminated foam sheet was not satisfied.
Further, in the container of this example, bubbles floated on the inner surface, and the appearance evaluation of the container was x: poor.
As a comprehensive evaluation, the adhesive strength between the layers (1) / (2) and the adhesive strength between the layers (2) / (4) were weak, bubbles were generated on the inner surface in the appearance evaluation of the container, and the evaluation of lid peeling. The polyolefin resin layer part was peeled off in a bag shape, and x: defective.

[Comparative Example 5]
A 30 μm polystyrene resin film SPH (manufactured by Oishi Sangyo Co., Ltd.) was used instead of the polyolefin resin laminated film, and the heat roll temperature under heat lamination conditions was 170 ° C. and the take-up speed was 12.0 m / min. In the same manner as in Example 1, a polystyrene resin laminated foam sheet not having a polyolefin resin film was obtained, and a container was further produced.
The polystyrene-based resin laminated foam sheet and the container were measured and evaluated for each test item described above in the same manner as in Example 1, and the results are shown in Table 1.
Since this polystyrene-based resin laminated foam sheet does not have a polyolefin-based resin film, the container manufactured using this laminated foam sheet has a high moisture permeability of 1027 (g / m ² .30 days). .
The overall evaluation was poor in moisture permeability, and x: poor.

  From the results described in Table 1, in Examples 1 to 4 according to the present invention, when molded into a container, the generation of bubbles can be reduced, and the polystyrene system in which the glossiness of the polyolefin resin layer on the inner surface of the container is reduced. It has been demonstrated that resin laminated foam sheets and containers can be provided.

It is sectional drawing which shows one Embodiment of the polystyrene-type resin laminated foam sheet which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Polystyrene resin foam sheet, 2 ... Polystyrene resin film, 3 ... Adhesive layer, 4 ... Polyolefin resin film, 5 ... Polystyrene resin laminated foam sheet, 6 ... Polystyrene resin non-foam film, 7 ... Polyolefin resin Laminated film, 8 ... film laminated foam sheet.

Claims (10)

On one surface of the polystyrene resin foam sheet (1), a polystyrene resin film (2) having a thickness in the range of 5 μm to 24 μm, an adhesive layer (3), and a polyolefin system having a thickness in the range of 5 μm to 50 μm. The resin film (4) is laminated in order,
The adhesive strength between the polystyrene resin film (2) and the polyolefin resin film (4) is 500 gf or more, and the adhesive strength between the polystyrene resin foam sheet (1) and the polystyrene resin film (2). Is 650 gf or more,
And the glossiness of the surface of the said polyolefin resin film (4) side is 75% GL or less, The polystyrene resin laminated foam sheet (5) characterized by the above-mentioned.   The polystyrene resin according to claim 1, wherein a polystyrene resin non-foamed film (6) having a thickness in the range of 40 µm to 250 µm is laminated on the other surface of the polystyrene resin foam sheet (1). Laminated foam sheet.   The polystyrene resin laminated foam sheet according to claim 1 or 2, wherein the polyolefin resin film (4) is a polypropylene resin film.   The adhesive layer (3) is made of an adhesive selected from a polyurethane adhesive, a polyester adhesive, a polyether adhesive, an acrylic adhesive, and a vinyl acetate adhesive. The polystyrene-based resin laminated foam sheet according to any one of -3.   A polystyrene resin laminated foamed container obtained by thermoforming the polystyrene resin laminated foam sheet according to any one of claims 1 to 4 so that the inside thereof becomes the polyolefin resin film (4). .   6. The polystyrene-based resin laminated foam container according to claim 5, wherein the glossiness of the container inner surface is 65% GL or less. The moisture permeability of the container is 630 g / m ² · 30 days or less, and the polystyrene-based resin laminated foam container according to claim 5 or 6. An adhesive layer (3) comprising a polystyrene resin foam sheet (1), a polystyrene resin film (2) having a thickness in the range of 5 μm to 24 μm, and a polyolefin resin film (4) having a thickness in the range of 5 μm to 50 μm. And a polyolefin-based resin laminated film (7) formed by bonding via
The roll temperature is in the range of 180 to 210 ° C. in a state where the polystyrene resin film (2) side of the polyolefin resin laminated film (7) is superposed on one surface of the polystyrene resin foam sheet (1). The polystyrene-based resin foamed sheet (1) and the polystyrene-based resin film (2) are adhered to each other through a heat roll, and the polystyrene-based resin laminated foamed sheet (5) according to any one of claims 1 to 4 is used. A method for producing a polystyrene-based resin laminated foam sheet, which is characterized by being obtained.   As the polystyrene resin foam sheet (1), a film laminate in which a polystyrene resin non-foam film (6) having a thickness of 40 μm to 250 μm is laminated on the other surface of the polystyrene resin foam sheet (1). The method for producing a polystyrene-based resin laminated foam sheet according to claim 8, wherein the foam sheet (8) is used.   Immediately after adhering the polystyrene resin foam sheet (1) and the polystyrene resin film (2) through the hot roll, the polystyrene resin laminated foam sheet (5) is passed through a cooling roll having a roll temperature of 40 ° C. or less. It cools, The manufacturing method of the polystyrene-type resin laminated foam sheet of Claim 8 or 9 characterized by the above-mentioned.

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