JP2006272799A - Heat-resistant polystyrene resin foaming laminated sheet and its molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat-resistant polystyrene resin foaming laminated sheet and its molded product by which the occurrence of blisters is reduced by strongly adhering the heat-resistant polystyrene resin foaming laminated sheet and a polypropylene resin film. <P>SOLUTION: The heat-resistant polystyrene resin foaming laminated sheet is constituted by laminating a heat-resistant foaming sheet comprising a heat-resistant polystyrene resin having a Vicat softening point specified by JIS K7206 of 110°C or more and the polypropylene resin film via a adhesive ink layer by heat fusion bonding, and the adhesive ink layer is constituted of at least two layers, an adhesive ink layer whose base material is a chlorinated polypropylene resin is arranged in the side of the polypropylene resin film, and an adhesive ink layer whose base material an acrylic resin is arranged in the side of the heat-resistant foaming sheet. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat-resistant polystyrene-based resin foam laminate sheet capable of increasing the range with excellent peel strength and a molded product formed by molding the sheet into a shape such as a container or a tray.

  In recent years, as microwave microwave ovens have rapidly become widespread, microwave ovens have also been used for heating cooked foods. For this purpose, containers made of crystalline polyethylene terephthalate (C-PET) and containers made of a low-foamed polypropylene sheet have been developed as containers suitable for this purpose. This type of container has heat resistance and suitability for a microwave oven. However, although these containers exhibit good suitability for microwave ovens, they have poor heat insulation properties, so that the temperature of the outer surface of the container rises in a short time as the temperature of the contents rises. For this reason, there is a problem that the contents cannot be held by hand while the contents are hot, and cannot be taken out of the range because the container is hot immediately after heating. In order to solve this drawback, the container may be made of a plastic foam with a high expansion ratio to improve the heat insulation of the container. However, a polypropylene resin foam having a high expansion ratio has poor rigidity and is unsuitable as a container.

  As a plastic foam having a high expansion ratio and excellent heat insulation, expanded polystyrene has been well known and has been widely used as a general food container. Among them, in particular, polystyrene resins having a Vicat softening point of 110 ° C. or higher, such as styrene-methacrylic acid copolymer resins, styrene-maleic anhydride copolymer resins, styrene-maleimide copolymer resins, polyparamethylstyrene resins, etc. Heat resistant polystyrene resin foam sheets are known. However, sufficient heat resistance cannot be obtained in the case of a container used for heating in a microwave oven only with this heat-resistant polystyrene resin foam sheet or a molded product thereof. Therefore, by further laminating a polypropylene film on the surface of the sheet to obtain a heat-resistant polystyrene-based resin foamed laminated sheet, it becomes possible to impart high heat resistance that could not be expressed with a heat-resistant polystyrene-based resin foam sheet alone. It was.

  However, this foamed laminated sheet has a further problem. That is, in order to laminate a polypropylene resin film and a polystyrene resin foam sheet, which are difficult to adhere to each other, they are bonded together via a resin layer that becomes a binder, or a polystyrene resin that becomes a polystyrene resin film and a binder layer in advance. Since many man-hours, such as carrying out dry lamination of the film which laminated | stacked the film, are required, there existed a problem which manufacturing cost became high. In addition, by interposing an extra binder layer, the weight per unit area of the foamed laminated sheet increases and the container that molded it becomes heavier, so the volume of containers and packaging waste in the recently enacted Container Recycling Law has been reduced. There was a problem that was not in line with this policy.

Moreover, as another problem, in packaged foods that are supposed to be heated in recent microwave ovens, many foods rich in oil are contained in the contents, and these may be referred to as microwave oven heating (hereinafter referred to as range up). Then, when only the oil component is directly attached to the container, the portion is locally heated, causing blistering-like peeling (referred to as “hibukule”), resulting in a problem of poor appearance. FIG. 3 is a cross-sectional view schematically showing a state of occurrence of bullets in a conventional laminated foamed sheet molded product. In FIG. 3, reference numeral 11 denotes a heat-resistant polystyrene resin foam laminate sheet, 12 denotes a heat-resistant polystyrene resin foam sheet, Reference numeral 13 denotes a polypropylene resin film, 14 denotes a light blur, and 15 denotes a blur. As shown in FIG. 3, the Hibukure 14 portion is in a state in which the heat-resistant polystyrene resin foam sheet 12 and the polypropylene resin film 13 are peeled off and the polypropylene resin film 13 is expanded, and when the expansion further proceeds, the blurring occurs. 15 and the appearance is remarkably deteriorated.
In order to prevent this, there has been a demand for a heat-resistant polystyrene-based resin foam laminate sheet and a molded container thereof that are less prone to peeling and can be improved in range with excellent peel strength.
Conventionally, technologies aimed at improving heat resistance in laminated foam sheets and the like are disclosed in, for example, Patent Documents 1 to 3.

  Patent Document 1 discloses a foam sheet made of a heat-resistant polystyrene resin having a Vicat softening point of 115 ° C. or more, which is extruded and foam-molded to an expansion ratio of 5 to 20 times and a thickness of 0.5 to 3.0 mm by an extruder. Using a laminated sheet obtained by laminating the print side of the film with a foam sheet and thermocompression bonding with a transparent polypropylene film printed with an adhesive ink containing a polyurethane resin or polyurethane prepolymer Thus, a method for producing a heat-resistant plastic container is disclosed, in which the inner layer of the container is formed by a polypropylene layer of a laminated sheet and heat-pressed with a mold.

  In Patent Document 2, printing is performed with an ink composition in which a chlorinated polypropylene primer is applied to one side of a thermoplastic elastic sheet, and a mixed treatment agent composed of an acrylic resin and a saturated polyester resin is mixed with the ink. A printed composite sheet is disclosed in which a processed printed thermoplastic elastic sheet is fused and integrated on one or both sides of a polyolefin foam sheet.

Patent Document 3 discloses an acid-modified polypropylene resin having an acid value of 10 to 150 mgKOH / g and a weight average molecular weight of 5,000 to 200,000 consisting of an unstretched polypropylene film and a foam sheet or filler sheet mainly composed of polypropylene. Disclosed is a method for producing a PP laminate, characterized in that the laminate is thermally laminated through an intermediate layer contained, and further between the unstretched polypropylene film and the intermediate layer, a polyurethane resin, an acrylic resin, and a polyamide resin And at least one kind of resin selected from the group of nitrified cotton and / or a printing ink containing a chlorinated polypropylene resin as a main binder resin, and then the printed surface is heat-laminated through the intermediate layer Is described.
Japanese Patent Publication No. 6-366 Japanese Examined Patent Publication No. 7-14655 JP 2003-80648 A

However, the above-described conventional technique has the following problems.
The prior art of Patent Document 1 describes the use of an adhesive ink containing a polyurethane resin or a polyurethane prepolymer. There was no hibukure due to peelability or range up, but it gave off a peculiar odor and was sometimes shunned as a food container.
In the prior art of Patent Document 2, chlorinated polypropylene resin and acrylic resin ink are used, but examination by adhesion to polystyrene resin is not performed.
In the prior art of Patent Document 3, polypropylene is used on the foam sheet side, but in order to maintain the strength as a range-up container, the foaming ratio of the foamed sheet is up to about 5 times. There is a problem that the container cannot be taken out from the microwave oven because it is hot. In addition, since the acid-modified polypropylene resin is provided in the intermediate layer, there is a problem that the weight is increased and the number of steps for laminating these is increased.

  The present invention has been made in view of the above circumstances, and provides a heat-resistant polystyrene-based resin foam laminate sheet and a molded product thereof with reduced generation of blurring by firmly bonding a heat-resistant polystyrene resin foam sheet and a polypropylene resin film. Objective.

  In order to achieve the above object, the present invention provides a heat-resistant foamed sheet made of a heat-resistant polystyrene resin having a Vicat softening point of 110 ° C. or higher as defined in JIS K7206 and a polypropylene resin film through an adhesive ink layer. A heat-resistant polystyrene-based foamed laminated sheet laminated by heat-sealing, and the adhesive ink layer is composed of at least two layers, and the adhesive property is based on a chlorinated polypropylene-based resin on the polypropylene-based resin film side. Provided is a heat-resistant polystyrene-based resin foam laminate sheet characterized in that an ink layer is provided, and an adhesive ink layer based on an acrylic resin is provided on the heat-resistant foam sheet side.

  In the heat-resistant polystyrene-based resin foam laminated sheet of the present invention, a polystyrene-based material having a Vicat softening point defined by JIS K7206 of 105 ° C. or lower between the heat-resistant foam sheet and an adhesive ink layer based on an acrylic resin. It is preferable that a foamed sheet or a non-foamed resin layer made of resin is laminated.

  The present invention also provides a heat-resistant polystyrene resin foam laminate sheet molded product obtained by thermoforming the heat-resistant polystyrene resin foam laminate sheet according to the present invention.

The heat-resistant polystyrene resin foam laminate sheet of the present invention is an adhesive ink comprising a heat-resistant foam sheet made of heat-resistant polystyrene resin and a polypropylene resin film, and a chlorinated polypropylene resin as a base material on the polypropylene resin film side. Layer, and an adhesive ink layer based on an acrylic resin on the heat-resistant foam sheet side, and are heat-sealed and laminated through at least two adhesive ink layers. A heat-resistant foam sheet and a polypropylene resin film can be firmly bonded by an ink layer, and a heat-resistant polystyrene-based resin foam laminate sheet with little odor and a molded product thereof can be provided.
Moreover, it is not necessary to interpose a binder layer between the heat-resistant foam sheet and the polypropylene resin film, the weight can be reduced, and the weight of a molded product such as a container formed using the sheet can be reduced.
In addition, since the heat-resistant foam sheet and the polypropylene resin film can be firmly bonded, the molded product obtained by thermoforming this sheet is less likely to cause blurring when heated in a microwave oven, and does not deteriorate the appearance. Can provide.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a container A which is an example of a heat-resistant polystyrene-based resin foam laminated sheet molded product according to the present invention. This container A is produced by thermoforming the heat-resistant polystyrene resin foam laminated sheet 1 according to the present invention shown in FIG. 2 into a container shape. In addition, although the container A of FIG. 1 has illustrated the rectangular container, the shape of the molded article which concerns on this invention is not limited to this, It shall be a bowl-shaped container, a cup-shaped container, a square tray, etc. Can do. Further, the dimensions of the container are not particularly limited.

  A heat-resistant polystyrene-based resin foam laminated sheet 1 shown in FIG. 2 includes a heat-resistant foamed sheet 2 made of a heat-resistant polystyrene-based resin and a polypropylene-based resin film 3, and a chlorinated polypropylene-based resin as a base material on the polypropylene-based resin film 3 side. The adhesive ink layer 4 and the heat-resistant foam sheet 2 are laminated by heat-sealing through the two adhesive ink layers of the acrylic resin base material on the heat-resistant foam sheet 2 side. ing.

The heat-resistant foam sheet 2 is a heat-resistant polystyrene resin having a Vicat softening point of 110 ° C. or higher as defined in JIS K7206, such as styrene-methacrylic acid copolymer, styrene-maleic anhydride copolymer, styrene-maleimide copolymer A heat-resistant polystyrene resin foam sheet obtained by extrusion foam molding of coalesced polypolymethylstyrene resin, etc., the heat-resistant polystyrene resin foam sheet, and a polystyrene resin having a Vicat softening point as defined in JIS K7206 of 105 ° C. or lower A heat-resistant polystyrene resin laminated foam sheet obtained by laminating a foam sheet (hereinafter referred to as a general-purpose polystyrene resin foam sheet), and the Vicat softening point defined in JIS K7206 is 105 ° C. Non-foamed resin consisting of the following polystyrene resins (Hereinafter referred to as a general-purpose polystyrene-based non-foamed resin layer), or a heat-resistant polystyrene-based resin-laminated foam sheet, or the heat-resistant polystyrene-based resin foam sheet, a general-purpose polystyrene-based resin foam sheet, and a general-purpose polystyrene-based non-foamed resin. It is desirable to use a heat-resistant polystyrene-based resin laminated foam sheet formed by laminating layers.
By laminating general-purpose polystyrene-based resin foam sheets, brittleness is reduced and moldability can be improved. Further, by laminating a general-purpose polystyrene-based non-foamed resin layer, strength and surface smoothness can be improved.
The method for laminating the general-purpose polystyrene-based resin foam sheet is not particularly limited, and a co-extrusion method, a heat fusion method using heat, an adhesion method using an adhesive, or the like can be appropriately used.
In addition, the method of laminating the general-purpose polystyrene-based non-foamed resin layer is not particularly limited, and is a co-extrusion method in which a molten resin is merged in a die at the tip of the extruder, and the molten resin is heated on the surface of the foam sheet. An extrusion laminating method for fusing and laminating, a heat laminating method for laminating a non-foamed resin film on the surface of the foamed sheet, a method for adhering the non-foamed resin film to the foamed sheet via an adhesive, etc. are used as appropriate. be able to.

  The heat-resistant polystyrene resin laminated foam sheet is preferably prepared by co-extruding (co-extrusion) a general-purpose polystyrene resin foam sheet or a general-purpose polystyrene non-foamed resin layer and the heat-resistant polystyrene resin foam sheet. Examples of the polystyrene resin used as the material for the general-purpose polystyrene resin foam sheet or the general-purpose polystyrene non-foamed resin layer used herein include styrene monomers such as styrene, methylstyrene, ethylstyrene, isopropylstyrene, dimethylstyrene, and paramethyl. Homopolymer of styrene, chlorostyrene, bromostyrene, vinyl toluene, vinyl xylene, or the styrene monomer and other monomers such as acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, methyl methacrylate, anhydrous Copolymers with vinyl monomers such as maleic acid and butadiene can be used. Among them, polystyrene resin, styrene-maleic anhydride copolymer, styrene-acrylic acid copolymer, high impact polystyrene resin (HIPS), styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene terpolymer, etc. Is preferably used. These can be used alone or in combination.

The polypropylene resin film 3 is particularly preferably a film made of polypropylene having a Vicat softening point of 140 ° C. or higher as defined in JIS K7206. The thickness of the polypropylene resin film 3 used in the present invention is preferably in the range of 15 to 100 μm, and more preferably in the range of 20 to 50 μm.
The polypropylene resin film may be any of an unstretched film, a uniaxially stretched film, and a biaxially stretched film, but an unstretched film having excellent moldability is preferable. Further, in order to improve the adhesion to the adhesive ink layer, the surface of the polypropylene resin film may be subjected in advance to a surface treatment such as corona discharge treatment, flame treatment or ozone treatment.

  The adhesive ink layer 4 based on the chlorinated polypropylene resin can contain a colorant, other adhesive resin components and the like in addition to the chlorinated polypropylene resin as the main component. The adhesive ink layer 4 based on this chlorinated polypropylene resin is a printing method on the surface of the polypropylene resin film 3 using the above-mentioned components, an organic solvent, and other additives as a printing ink. Is applied. The thickness of the adhesive ink layer 4 based on this chlorinated polypropylene resin is preferably in the range of 1 to 2 μm.

  Various inorganic pigments and organic pigments can be used as the colorant to be blended in the printing ink. Specific examples of inorganic pigments include colored pigments such as titanium oxide, bengara, antimony red, cadmium yellow, cobalt blue, bitumen, ultramarine, carbon black, graphite, calcium carbonate, kaolin, clay, barium sulfate, aluminum hydroxide, talc. And extender pigments. Examples of organic pigments include azo pigments, azo lake pigments, condensed azo pigments, copper phthalocyanine pigments, and condensed polycyclic pigments.

  As organic solvents, aromatic solvents such as toluene and xylene, which are highly soluble and dispersible in chlorinated polypropylene resins, and alicyclic solvents such as cyclohexane and methylcyclohexane are used as the main solvents. Ethyl acetate, propyl acetate, acetic acid An ester solvent such as amyl, a ketone solvent such as acetone and methyl ethyl ketone, and an alcohol solvent such as ethanol and propanol can be used as a cosolvent, and can be used in appropriate combinations as necessary.

  As a method for preparing the printing ink, a known method in which a chlorinated polypropylene resin, a colorant, an additive and the like are dissolved and dispersed in the organic solvent can be employed. Moreover, the method of printing the prepared printing ink on the polypropylene resin film 3 surface is not specifically limited, It can select suitably from conventionally well-known printing methods, such as a gravure printing system and a flexographic printing system, and can employ | adopt. The viscosity of the printing ink can also be appropriately selected according to the printing method.

  The adhesive ink layer 5 based on the acrylic resin can contain a colorant, other adhesive resin components and the like in addition to the acrylic resin as the main component. As the acrylic resin as the main component, an alkyl ester or glycidyl ester of acrylic acid or methacrylic acid is preferable. The thickness of the adhesive ink layer 5 based on this acrylic resin is preferably in the range of 1 to 2 μm.

  The adhesive ink layer 5 based on the acrylic resin is the same as the adhesive ink layer 4 based on the chlorinated polypropylene resin. Alternatively, it can be applied on the adhesive ink layer 4 based on the chlorinated polypropylene resin printed on the surface of the polypropylene resin film 3, and in particular, it is continuously printed on the adhesive ink layer 4. Is preferred. As in the case of the adhesive print layer 4 described above, the adhesive ink layer 5 based on this acrylic resin is a mixture of an acrylic resin as a main component, other components such as a colorant, and an organic solvent. Thus, a printing ink can be prepared and printed by the same method as in the case of the adhesive printing layer 4. The viscosity of the printing ink can also be appropriately selected according to the printing method.

  The adhesive ink layer 4 based on a chlorinated polypropylene resin has good heat-fusibility to the polypropylene resin film 3. The adhesive ink layer 5 based on an acrylic resin has good heat-fusibility to the heat-resistant foam sheet 2. The adhesive ink layer 4 based on the chlorinated polypropylene resin and the adhesive ink layer 5 based on the acrylic resin exhibit good heat-fusibility. Therefore, this heat-resistant polystyrene-based resin foam laminated sheet 1 has an adhesive property in which a heat-resistant foamed sheet 2 made of polystyrene-based resin and a polypropylene-based resin film 3 are used as a base material on the polypropylene-based resin film 3 side. Since the ink layer 4 and the heat-resistant foam sheet 2 side are laminated by heat-sealing through the two adhesive ink layers 4 and 5 of the adhesive ink layer 5 based on an acrylic resin. The heat-resistant foam sheet 2 and the polypropylene resin film 3 can be firmly bonded by the adhesive ink layers 4 and 5.

Since the heat-resistant polystyrene-based resin foam laminated sheet 1 has the above-described configuration, the heat-resistant foamed sheet 2 made of a polystyrene-based resin and the polypropylene-based resin film 3 that are inherently difficult to adhere can be easily bonded. Therefore, it is possible to obtain a heat-resistant foamed laminated sheet with less odor, and particularly to provide a heat-resistant foamed laminated sheet suitable for food containers, trays and the like, and molded articles thereof.
In addition, the heat-resistant polystyrene-based resin foam laminated sheet 1 can be produced by firmly laminating the heat-resistant foamed sheet 2 and the polypropylene resin film 3 without interposing an adhesive resin layer called a binder. It is possible to reduce the weight of containers and trays obtained by molding this sheet.
In addition, since the heat-resistant foam sheet 2 and the polypropylene resin film 3 can be firmly bonded, a molded product obtained by thermoforming this sheet is less likely to cause a blur when heated in a microwave oven, resulting in a decrease in appearance. Providing products that are not invited.

  Next, an example of the manufacturing method of this heat-resistant polystyrene-type resin foam lamination sheet 1 is demonstrated with reference to FIG.4 and FIG.5. FIG. 4 shows a rotary press in which an adhesive ink layer 4 based on a chlorinated polypropylene resin and an adhesive ink layer 5 based on an acrylic resin are continuously formed on the surface of a polypropylene resin film 22. A printing machine is illustrated, (a) is a block diagram of the rotary printing machine 20, and (b) is an enlarged view of the printing units 23A and 23B. FIG. 5 is a configuration diagram showing a case where the laminating process of the heat resistant foam sheet 2 and the printed film 25 is performed by a thermal laminating method.

  In this manufacturing method, first, an adhesive ink layer 4 based on a chlorinated polypropylene resin and an acrylic resin are used as a base material on the surface of the polypropylene resin film 2 using a rotary printing machine 20 shown in FIG. The adhesive ink layer 5 to be printed is continuously printed to produce a printed film 25. The polypropylene resin film 22 drawn out from the film supply roll 21 is sent to the first printing unit 23A through a plurality of guide rolls, applied with printing ink containing a chlorinated polypropylene resin, and placed in the first drying chamber 24A. Then, the ink is dried to form the adhesive ink layer 4, and then sent to the second printing unit 23 </ b> B, and the printing ink containing the acrylic resin is applied onto the adhesive ink layer 4, and the second drying chamber 24B, the ink is dried to form the adhesive ink layer 5, and the printed film 25 is taken up on the take-up roll 26.

  As shown in FIG. 4B, the first and second printing sections 23A and 23B are configured to include a pressure roll 27, a printing roll 28, a container 30 containing printing ink 29, and a blade 31. . When the polypropylene-based resin film 22 passes between the printing roll 28 partially immersed in the printing ink 29 and the pressure-bonding roll 27 provided thereon, the printing ink 29 adhered to the surface of the printing roll 28. Is transferred and coated on the surface, and the coating thickness is adjusted by the blade 31 and then sent to the drying chambers 24A and 24B.

  The printed film 25 produced using the above-described rotary printing press 20 is bonded to the heat resistant foamed sheet 2 by a heat laminating method to produce the heat resistant polystyrene-based resin foam laminated sheet 1.

  In the heat laminating method shown in FIG. 5, the heat-resistant foam sheet 2 and the printed film 25 are superposed and passed between the cooling roll 34 and the dielectric heating roll 35 and heated to use an acrylic resin as a base material. The adhesive ink layer 5 and the heat resistant foam sheet 2 are heat-sealed. The obtained heat-resistant polystyrene-based resin foam laminated sheet 1 is wound up on a roll.

In addition, this invention is not limited to the illustration mentioned above, A various correction and change are possible.
For example, the colorants of the first adhesive print layer 4 and the second adhesive print layer 5 may be the same or different.
The adhesive ink layer may be three or more layers.

[Example 1]
<Method for producing heat-resistant polystyrene-based resin foam sheet>
In an extruder in which an extruder with an inner diameter of 150 mm and a 180 mm extruder are connected as an extruder, T080 (Vicat softening point 116 ° C., MI = 2.0, Toyo Styrene Co., Ltd.) is a styrene-methacrylic acid copolymer as a heat-resistant polystyrene resin. 95 parts by mass), 5 parts by mass of Toughprene 125 (Asahi Kasei Co., Ltd.) which is a styrene-butadiene copolymer, and 0.8 parts by mass of DSM1401A (manufactured by Toyo Styrene Co.) which is talc MB After melting and kneading at a temperature of 230 ° C., 3.0 parts by mass of butane (iso / normal = 50/50) was added as a foaming agent. Thereafter, the resin was cooled to 169 ° C. suitable for foaming.
Further, the inner surface of the foamed sheet extruded from a circular die set at a tip of 200 mm and a slit clearance of 0.45 mm was cooled by a cooling mandrel having an outer diameter of 673 mm and a length of 1000 mm. The outer periphery was also cooled with air, then cut into two sheets and wound into a roll. The obtained heat-resistant foam sheet had a thickness of 1.8 mm and a density of 0.111 g / cm ³ .

<Manufacture of a polypropylene resin film provided with an adhesive ink layer>
Pel-Snw (Osaka Ink Co., Ltd.), an adhesive ink based on chlorinated polypropylene resin, is printed on an unstretched polypropylene film (Santox Co., CPKT series) with a thickness of 30 μm. Printing was performed with STIPURI (manufactured by Osaka Ink Co., Ltd.), which is an adhesive ink based on an acrylic resin, to obtain a polypropylene resin film provided with two adhesive ink layers.

<Manufacture of heat-resistant polystyrene-based resin foam laminate sheet>
Adhesive ink using acrylic resin as a base material with a polypropylene resin film provided with a heat-resistant foam sheet and an adhesive ink layer at a contact pressure of 0.2 MPa and a laminating temperature of 160 ° C. using a dielectric heating roll having an outer diameter of 300 mm Heat-adhesion was carried out so that the layer side would be the heat-resistant foamed sheet side to obtain a heat-resistant polystyrene-based resin foam laminated sheet.

<Measurement method of Vicat softening point>
A test piece having a size of 12.7 × 64 × 6.4 mm was molded at a cylinder temperature of 220 ° C. using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine. Using this test piece, measurement was performed under the condition of a load of 49.0 N in accordance with JIS K7206 (unit: ° C.).

<Measurement method of peel strength>
Using a Tensilon universal testing machine UCT-10T manufactured by Orientec Co., Ltd., measurement was performed in a peel test mode. The test speed was 200 mm / min, and the maximum point load was the peel strength. The test piece is 15 × 175 mm with 180 degree peeling. The test starts after peeling about 10 mm.

<Manufacturing method of container>
The obtained heat-resistant polystyrene-based resin laminated foam sheet was molded by a single molding machine (FM-6AS (manufactured by Tosei Sangyo Co., Ltd.)). Molding conditions are as follows: After heating at a furnace atmosphere temperature of 160 ° C. and a heating time of 13 to 15 seconds, a rectangular resin having a shape of 120 × 180 × 35 mm shown in FIG. A container was formed.

<Evaluation method of odor sensory test>
The sensory test for odor was conducted immediately after obtaining the heat-resistant polystyrene-based resin laminated foam sheet and immediately after producing the container by putting the obtained section or container in a plastic bag.

<Evaluation method of microwave oven heating>
20 g of a mixture of water / oil = 50/50 was put as the contents in the obtained container and heated in a microwave oven. The output of the microwave oven was 500 W, and the heating time was 30 seconds. The microwave oven used was EM-1503T (manufactured by Sanyo Electric Co., Ltd.).
After heating, the removed container was visually evaluated in three stages according to the following categories.
◎… No float ○… Float less than 5mm occurs (4 or less)
× ... Many floats (5 or more) of less than 5 mm occur or floats of 5 mm or more occur

<Results of each evaluation>
Both the section and the container of Example 1 had no odor, the peel strength was 370 g, and the microwave oven evaluation was ◎.

[Example 2]
<Manufacture of heat-resistant polystyrene resin foam sheet (coextrusion)>
In an extruder (A) in which an extruder with an inner diameter of 150 mm and a 180 mm extruder are connected as an extruder, T080 (Vicat softening point 116 ° C., MI = 2.0, which is a styrene-methacrylic acid copolymer as a heat-resistant polystyrene resin) 95 parts by mass of Toyo Styrene Co., Ltd., 5 parts by mass of Taffeprene 125 (Asahi Kasei Co., Ltd.), a styrene-butadiene copolymer, and 0.8 parts by mass of DSM1401A (Toyo Styrene Co., Ltd.), talc MB After melting and kneading at a maximum temperature of 230 ° C., 3.9 parts by mass of butane (iso / normal = 50/50) was added as a foaming agent. Thereafter, the resin was cooled to 165 ° C. suitable for foaming.
On the other hand, in an extruder (B) in which an inner diameter 115 mm extruder and a 150 mm extruder are connected, 100 mass of polystyrene resin HRM-12 (Vicat softening point 101 ° C., MI = 2.0, manufactured by Toyo Styrene Co., Ltd.) Part of the raw material containing 0.6 parts by mass of MO60 (produced by Kihara Kasei Co., Ltd.), which is talc MB, is melted and kneaded at a maximum temperature of 240 ° C., and then butane (iso / normal = 50/50) is used as a blowing agent. 2 parts by mass were added. Thereafter, it was cooled to a resin temperature of 156 ° C. suitable for foaming having closed cells.
Extruder (A) and Extruder (B) are merged in a merging die, laminated, and a foam sheet extruded from a circular die set at a tip diameter of 190 mm and slit clearance of 0.45 mm The inner surface was cooled with a cooling mandrel having an outer diameter of 673 mm and a length of 1000 mm, and at the same time the outer periphery was cooled with air at a cooling temperature of 30 ° C., then cut into two sheets and wound into a roll.
The obtained laminated foam sheet is composed of a heat-resistant foam layer made of a heat-resistant polystyrene resin having a Vicat softening point of 110 ° C. or higher and a foam layer made of a polystyrene resin having a Vicat softening point of 105 ° C. or less. The thickness ratio was 1: 1, the total thickness was 2.0 mm, and the total density was 0.120 g / cm ³ .

<Manufacture of a polypropylene resin film provided with an adhesive ink layer>
The same operation as in Example 1 was performed.

<Manufacture of heat-resistant polystyrene-based resin foam laminate sheet>
Adhesive ink layer using acrylic resin as a base material with a polypropylene resin film provided with a heat-resistant foam sheet and an adhesive ink layer at a contact pressure of 0.2 MPa and a laminating temperature of 160 ° C. using a dielectric heating roll having a diameter of 300 mm The heat-resistant foamed sheet was heat-bonded so that the Vicat softening point of the heat-resistant foamed sheet was a foamed layer side made of a polystyrene-based resin having a temperature of 105 ° C. or lower, to obtain a heat-resistant polystyrene-based resin foamed laminated sheet.

<Manufacturing method of container>
The same operation as in Example 1 was performed.

<Results of each evaluation>
Both the section and the container of Example 2 had no odor, the peel strength was 350 g, and the microwave oven evaluation was ◎.

[Example 3]
Except that the lamination temperature was set to 140 ° C. in <Production of heat-resistant polystyrene-based resin foam laminated sheet>, sensory evaluation, peeling evaluation, and microwave evaluation were performed in the same manner as in Example 2.
As a result, both the section and the container of Example 3 had no odor, the peel strength was 210 g, and the microwave oven evaluation was ○.

[Comparative Example 1]
In <Manufacture of polypropylene-based resin film provided with an adhesive ink layer>, a polypropylene-based resin film printed only with Pel-Snw (Osaka Ink Co., Ltd.), which is an adhesive ink based on a chlorinated polypropylene resin, is used. Except for the above, it was performed in the same manner as in Example 1, and sensory evaluation, peeling evaluation, and microwave evaluation were performed.
As a result, both the section and the container of Comparative Example 1 had no odor, the peel strength was 85 g, and the microwave oven evaluation was x.

[Comparative Example 2]
In <Manufacture of polypropylene-based resin film provided with an adhesive ink layer>, a polypropylene-based resin film printed only with Pel-Snw (Osaka Ink Co., Ltd.), which is an adhesive ink based on a chlorinated polypropylene resin, is used. Except for the above, it was carried out in the same manner as in Example 2, and sensory evaluation, peeling evaluation and microwave evaluation were performed.
As a result, both the section and the container of Comparative Example 2 had no odor, the peel strength was 70 g, and the microwave oven evaluation was x.

[Comparative Example 3]
Except that the lamination temperature was 140 ° C. in <Production of heat-resistant polystyrene-based resin foam laminated sheet>, the same method as Comparative Example 2 was performed, and sensory evaluation, peeling evaluation, and microwave evaluation were performed.
As a result, both the section and the container of Comparative Example 3 had no odor, the peel strength was 5 g, and the microwave oven evaluation was x.

[Comparative Example 4]
In <Manufacture of a polypropylene resin film provided with an adhesive ink layer>, as an adhesive ink, a polypropylene resin film printed only with LB (made by Osaka Ink Co., Ltd.), which is an adhesive ink based on a urethane resin. Except having used, it carried out by the method similar to Example 2, and sensory evaluation, peeling evaluation, and microwave oven evaluation were performed.
As a result, both the section and the container of Comparative Example 4 had a strong odor of x, a peel strength of 330 g, and a microwave oven evaluation of ◯.

It is a perspective view which shows the container of an example of the heat-resistant polystyrene-type resin foaming laminated sheet molded product which concerns on this invention. It is sectional drawing which shows an example of the heat-resistant polystyrene-type resin foam lamination sheet which concerns on this invention. It is sectional drawing which illustrates the state of the occurrence of a bullet in a conventional container. The rotary printing machine used for manufacture of a heat-resistant polystyrene-type resin foam lamination sheet is shown, (a) is a block diagram of a rotary printing machine, (b) is an enlarged view of a printing part. It is a block diagram of the apparatus for lamination used for manufacture of a heat-resistant polystyrene-type resin foam lamination sheet.

Explanation of symbols

A ... container (heat-resistant polystyrene resin foam laminate sheet molded product), 1 ... heat-resistant polystyrene resin foam laminate sheet, 2 ... heat-resistant polystyrene resin foam sheet, 3 ... polypropylene resin film, 4 ... chlorinated polypropylene resin base Adhesive ink layer as a material, 5 ... Adhesive ink layer based on an acrylic resin.

Claims (3)

A heat-resistant polystyrene system in which a heat-resistant foamed sheet made of a heat-resistant polystyrene resin having a Vicat softening point of 110 ° C. or higher as defined in JIS K7206 and a polypropylene resin film are heat-sealed through an adhesive ink layer. A resin foam laminated sheet,
The adhesive ink layer comprises at least two layers, an adhesive ink layer based on a chlorinated polypropylene resin is provided on the polypropylene resin film side, and an acrylic resin is provided on the heat resistant foam sheet side. A heat-resistant polystyrene-based resin foam laminated sheet, characterized in that an adhesive ink layer as a material is provided.   A foamed sheet or a non-foamed resin layer made of a polystyrene-based resin having a Vicat softening point of 105 ° C. or less as defined in JIS K7206 is laminated between the heat-resistant foamed sheet and an adhesive ink layer based on an acrylic resin. The heat-resistant polystyrene-based resin foam laminated sheet according to claim 1, wherein A heat-resistant polystyrene resin foam laminate sheet molded product obtained by thermoforming the heat-resistant polystyrene resin foam laminate sheet according to claim 1 or 2.

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