JP2007090662A - Laminated film or sheet having foamed resin layer, and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated film or sheet comprising a foamed layer laminated on a substrate, which is useful for a material having a diathermacy for manufacturing such as a paper container, an aluminum foil container and a film or sheet for packaging, and to provide a method for readily manufacturing the same, with high productivity and at a low cost. <P>SOLUTION: The laminated film or sheet including at least a substrate and a thermoplastic resin foamed layer is characterized in that a thermoplastic resin composition containing a foaming agent is made to foam to form, when it is extruded on the substrate to be laminated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminated film or sheet and a method for producing the same, and more particularly to a laminated film or sheet having a specific thermoplastic resin foam layer formed by foaming during extrusion lamination and a method for producing the same.

  Conventionally, paper used for containing and packaging heated or cooled foods and beverages, containers, films, and sheets made of a base material such as polyester, in order to impart heat insulation properties to the paper or For example, a resin foam layer made of, for example, a vinyl chloride resin, a polystyrene resin, a polyurethane resin, a polyolefin resin, or the like is frequently laminated on the surface of a plastic substrate. Many inventions have already been proposed.

  For example, in Patent Document 1, a blank sheet is produced by punching a laminated sheet provided with a paper layer as a base material and a polypropylene resin layer as an innermost layer and a layer of low density polyethylene or a copolymer thereof as a foamed layer as an outermost layer. A paper container in which a resin foam layer is formed by foaming in a heating furnace after forming the blank board into a container shape is disclosed. Patent Document 2 discloses a polyethylene resin foam layer from the inner surface to the outer surface, A heat insulating bag made of a laminated sheet laminated in the order of a polyethylene resin heat-fusible layer and a substrate is disclosed.

  Further, Patent Document 3 discloses an ethylene / α-olefin polymerized using a metallocene catalyst as a synthetic resin in a foam laminated sheet in which a foamed layer made of a synthetic resin composition mainly composed of an olefin resin is formed. Foam made of a synthetic resin composition in which a copolymer is mixed with at least one selected from low density polyethylene, linear low density polyethylene and olefin rubber, and a foaming agent is added to this synthetic resin. An invention of a foamed laminated sheet obtained by laminating a heat-resistant synthetic resin layer with a substrate and then foaming by heating is disclosed.

  A laminated film or sheet obtained by laminating such a resin foam layer on a base material or a molded product made of them is, for example, a container, a sheet, or the like as in the inventions of Patent Document 1, Patent Document 3, and the like. After forming into an article shape, the resin foam layer is formed by heating and foaming to obtain a product, or already foamed as in the invention of the method for producing a polypropylene resin laminated foam sheet described in Patent Document 4. In general, a non-foamed resin layer or a base film is laminated on a sheet-like material by extrusion lamination or the like.

  In the above general method, since the resin foaming step and the laminating step are performed in separate steps, much labor and time are required, and there is a problem in terms of productivity improvement.

Even in an attempt to rationalize the above processes and further reduce production costs, a specific case, for example, a base material and a foam layer are both thermoplastic resins that can be extruded, and both are, for example, polyethylene resins. In the case of substantially the same kind of material, it has already been proposed.
A resin melt for forming a resin layer made of a polyethylene resin composition and a resin composition for forming a foam layer made of a polyethylene resin composition are introduced into an annular die and coextruded from the annular die, thereby at least forming the foam layer. It describes that a cylindrical laminated foam having a resin layer laminated on one side is formed.

  However, the method of Patent Document 5 described above may be used when the base material and the resin constituting the foamed layer are different, particularly when the base material is not a thermoplastic resin such as paper, or even if it is a thermoplastic resin. When the difference in physical properties such as the melting point between the base resin and the foamed layer resin is large and the coextrusion is not possible, the above method cannot be adopted. Therefore, the above proposal is sufficient for the conventional request. I couldn't say it was a response.

Japanese Patent Laid-Open No. 2003-341752 JP 2001-270572 A JP 11-129421 A JP 2005-119147 A JP 2004001401 A

  The present inventors have been searching for various solutions that can be widely responded to the above-mentioned demands. For example, foaming agents such as olefin polymer compositions can be applied to substrates such as paper, aluminum foil, and PET resin. When laminating the containing thermoplastic resin composition, the idea was to complete the formation of a foamed layer in the apparatus at the same time during the lamination operation using an extrusion laminating apparatus.

  As a result, the present inventors have completed a method capable of obtaining a product that is almost satisfactory, except when forming a foam layer having a particularly high expansion ratio or when operating under operating conditions at a particularly high processing speed.

  Furthermore, unexpectedly, in the course of the study, in the product obtained by the method of the present invention, that is, in the laminated film or sheet having a foam layer, the foam layer has an infinite number of fine elongated shapes. It contains foam cell groups, and from the local density of the dispersion density of the foam cell groups, it was discovered that the appearance exhibits a vertical stripe pattern on a frosted glassy translucent ground, and the laminated film or sheet is used as a decorative article. It has also been found that it can be used sufficiently for other applications.

  Accordingly, an object of the present invention is to provide a laminated film or sheet in which a foam layer useful as a raw material for producing paper containers, aluminum foil containers, packaging films, sheets and the like with heat insulation properties is laminated on a substrate. And providing a method for producing the laminated film or sheet simply, with good productivity and at low cost.

  Another object of the present invention is to contain a myriad of fine elongated foam cells, and from the local density of the dispersion density of the cells, the appearance of streaky stripes on the frosted glassy translucent ground. An object of the present invention is to provide a laminated film or sheet useful as a decorative article material on which a foamed layer to be presented is laminated, and to provide a method for producing the laminated film or sheet simply and with good productivity at low cost.

  According to the present invention, a laminated film or sheet including at least a base material and a thermoplastic resin foam layer, the foam layer extruding a thermoplastic resin composition containing a foaming agent and laminating the base material on the base material. There is provided a laminated film or sheet characterized by being foamed.

The laminated film or sheet of the present invention is a film or sheet obtained by foaming a foaming agent-containing thermoplastic resin composition at the time of extrusion lamination, and the foamed layer is formed simultaneously with the lamination to the substrate. This is a structural feature.
The foam layer of the present invention preferably contains an infinite number of fine elongated foam cell groups, thereby imparting high heat insulating properties to the substrate, and more preferably, the local density of the dispersion density. Due to the light and shade, the appearance is a cloudy glassy translucent ground with vertical stripes.
Thereby, the laminated film or sheet of the present invention is a raw material for producing paper containers, aluminum foil containers, packaging films, sheets, etc., which are provided with heat insulation necessary to accommodate high-temperature foods and beverages. It is also useful as a material for producing decorative articles that require an aesthetic appearance.

  More preferably, the laminated film or sheet is formed by further laminating at least one layer made of a thermoplastic resin not containing a foaming agent. In particular, the laminated film or sheet is made of a thermoplastic resin not containing the foaming agent. It is preferable that it is formed by coextrusion of at least one layer and the foaming agent-containing thermoplastic resin composition.

  Further, the layer made of the thermoplastic resin not containing the foaming agent is a transparent layer or a colored layer, and the layered one side of the thermoplastic resin foam layer is used for pattern diversification and pattern protection. Particularly preferable from the viewpoint.

The expansion ratio of the thermoplastic resin foam layer is preferably 1.2 to 5 times.
Furthermore, it is particularly preferable that the thermoplastic resin constituting the foam layer is composed of an ethylene polymer.

Furthermore, according to the present invention, the foaming agent-containing thermoplastic resin composition is melt-extruded from a die of an extrusion laminator, and the cooling roll is placed in a state where one surface of the extruded molten web and one surface of the substrate are overlapped. In a manufacturing method of a laminated film or sheet having a step of passing through a gap with a nip roll and laminating the two together, a cooling roll and a nip roll after the foaming agent-containing thermoplastic resin composition exits the die And a method for producing a laminate, wherein foaming is completed in a period until it finishes passing through the gap,
And, a foaming agent-containing thermoplastic resin composition and a resin or resin composition not containing a foaming agent are melt-coextruded from a die of a coextrusion laminator, and one side of the extruded molten web and one side of the substrate are overlapped. In the manufacturing method of a laminated film or sheet having a step of passing through a gap between a cooling roll and a nip roll in a state of being made and thermally bonding and laminating both, the foaming agent-containing thermoplastic resin composition includes a die. Each of the methods for producing a laminate is characterized in that foaming is completed in a period from when it exits until it passes through the gap between the cooling roll and the nip roll to complete the formation of the foamed layer.

In each of the above methods of the present invention, the foam layer is preferably formed by adjusting the extrusion resin temperature of the extrusion laminator, the processing speed, the air gap, and the gap length between the cooling roll and the nip roll.
Further, in the adjustment, the extrusion resin temperature is in the range of 150 to 300 ° C., the extrusion laminator processing speed is in the range of 5 to 150 m / min, the air gap is in the range of 50 to 150 mm, and the gap length between the cooling roll and the nip roll is 0. It is preferable to adjust each within a range of ˜2 mm.

  As described above, the laminated film or sheet having the foamed layer of the present invention is formed by extrusion-foaming and laminating a foaming agent-containing thermoplastic resin composition on a substrate, and the foamed layer is formed simultaneously with the lamination to the substrate. This foam layer contains a myriad of fine elongated foam cells, thereby imparting high heat insulating properties to the base material, and the appearance of the foam layer from the local density of the dispersion density. A streaky pattern of vertical stripes on a cloudy glassy translucent ground.

Thereby, the laminated film or sheet of the present invention is a raw material for producing paper containers, aluminum foil containers, packaging films, sheets, etc., which are provided with heat insulation necessary to accommodate high-temperature foods and beverages. It is also useful as a material for producing decorative articles that require an aesthetic appearance.
Further, according to the method of the present invention, the laminated film or sheet can be produced simply and with good productivity at low cost.

Embodiments according to the present invention will be described below in detail and specifically with reference to the drawings.
FIG. 1 shows an example of an apparatus (extrusion laminator) for producing a laminated film or sheet according to the present invention.
In the apparatus 10 of FIG. 1, reference numeral 1 is a cooling roll, 2 is a nip roll, 3 is a T die, 4 is a substrate, 5 is a molten polymer flow path in the die, 5 ′ is a manifold, 6 is a laminated film, Reference numeral 7 denotes an air gap, 8 denotes a gap between the cooling roll 1 and the nip roll 2, and a denotes a molten web in progress of foaming.

For example, in order to manufacture the laminated sheet of the present invention using the apparatus 10, first, the base material layer 4 such as paper or PET is placed along the nip roll 2 while the gap 8 between the nip roll 2 and the cooling roll 1 is formed. Pull out and take along the cooling roll 1.
At this time, the melt-kneaded foaming agent-containing polymer composition is pressed down from the flow path 5 in the T die 3 and is expanded to the full width of the die by the manifold 5 ′, and then pushed out of the T die 3 as a molten web a. put out.

  The molten web a extruded out of the T-die 3 immediately starts to foam, and continues to form layered foam while flowing down the distance of the air gap 7, reaching the gap 8 between the nip roll 2 and the cooling roll 1, where the foaming is performed. When the molten web a layer and the base material layer 4 are pressure-bonded and passed through the gap, the formation of the foamed layer and the lamination of the base material layer and the layer are completed at the same time. obtain.

The laminated sheet thus obtained has an infinite number of elongated foamed cells in the foamed polymer layer, and the appearance is schematically shown in FIG. As shown in Fig. 4, vertical stripes appear on the frosted glassy translucent ground.
Thereby, the laminated sheet of the present invention not only has excellent heat insulation, but also has an aesthetic effect based on the above pattern and also has excellent decorativeness.

  For example, in the case where a laminated film or sheet having a further non-foamed resin layer laminated on the foamed layer is produced by coextrusion, the extrusion die portion 3 of the extrusion laminator is used as a coextrusion die. The foamed resin composition was extruded by coextruding the foaming agent-containing resin composition from the flow path on the side in contact with the substrate surface and the resin not containing the foaming agent from the flow path on the side away from the base material. While the material-melting web is foamed, one surface is thermally bonded to the substrate and the other surface is thermally bonded to the resin web not containing the foaming agent.

  The expansion ratio of the foamed resin layer is 1.2 to 5 times, more preferably 1.5 to 4 times the layer thickness in the unfoamed state. From the viewpoints of the aesthetic effect of the property and appearance pattern, etc.

  As a base material used for the laminated film or sheet of the present invention, a base material made of a material that can be processed in a processing apparatus line such as an extrusion laminator and can be thermally bonded to the foamed layer resin. If it can be used, there is no particular limitation.

As a base material in the present invention, a polyester resin such as PET resin, a polyamide resin such as nylon 6 resin, a polyolefin resin such as polypropylene resin, a metal foil such as aluminum foil, paper, non-woven fabric, felt Among them, paper, PET, and aluminum foil are particularly preferable.
Moreover, when a base material consists of resin films or sheets, such as a polyester-type resin and a polyamide-type resin, what has a stretching orientation is more preferable.

Next, as the thermoplastic resin used in the foaming agent-containing thermoplastic resin composition for forming the foamed layer in the present invention,
It can be used without particular limitation as long as it is a thermoplastic resin that can be thermally bonded to the base material and can form a foamed film. Examples of such resins include polyester resins, polyamide resins, Polyolefin resins can be exemplified, but among these, polyolefins, particularly ethylene polymers are preferred.
As the ethylene polymer, in addition to polyethylenes such as high density polyethylene, low density polyethylene, linear low density polyethylene, metallocene catalyzed polymerized linear low density polyethylene, ethylene / α-olefin mainly composed of ethylene Copolymers such as ethylene and propylene, 1-butene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 4-methyl-1-pentene, etc. Polymer.

Ethylene / unsaturated carboxylic acid copolymer or ethylene / unsaturated carboxylic acid ester copolymer based on ethylene, for example, ethylene and acrylic acid, methacrylic acid, ethacrylic acid, fumaric acid, maleic acid, monoalkyl maleate Copolymer of unsaturated carboxylic acid such as maleic anhydride, or unsaturated carboxylic acid such as ethylene and alkyl acrylate, alkyl methacrylate, ethacrylic acid alkyl ester, fumaric acid dialkyl ester, maleic acid dialkyl ester, etc. Copolymer with ester.
In addition, as said alkyl ester, ester, such as methyl, ethyl, n-butyl, i-butyl, 2-ethylhexyl, isooctyl, can be mentioned as a suitable example.

  A multi-component copolymer such as ethylene / unsaturated carboxylic acid / unsaturated carboxylic acid ester terpolymer comprising ethylene and the above unsaturated carboxylic acid and unsaturated carboxylic acid ester,

  Zinc or alkali metal ionomer of the ethylene / unsaturated carboxylic acid copolymer or ethylene / unsaturated carboxylic acid / unsaturated carboxylic acid ester terpolymer,

Further, ethylene / vinyl acetate copolymers and partially saponified products thereof, ethylene / vinyl propionate copolymers and partially saponified products thereof, and ethylene-based polymers such as polyvinyl alcohol can be exemplified.
Furthermore, a resin composition in which two or more of these polymers are mixed can also be used.

  Of these, low-density polyethylene such as low-density polyethylene, linear low-density polyethylene, metallocene-catalyzed polymerized linear low-density polyethylene, and ethylene / unsaturated carboxylic acid copolymers such as ethylene (meth) acrylic acid copolymer. Polymers and ionomers such as alkaline earth metals or alkali metal ionomers of ethylene (meth) acrylic acid copolymers can be preferably used. Among them, particularly preferred polymers are ethylene (meth) acrylic acid copolymers. Zinc ionomer, sodium ionomer, and potassium ionomer, most preferably zinc ionomer and sodium ionomer having a neutralization degree of 90 mol% or more of an ethylene (meth) acrylic acid co-layer having a (meth) acrylic acid content of 5 to 30% by weight. , Potassium ionomer.

  As the foaming agent to be blended in the polymer composition, it can be uniformly dispersed and mixed in the polymer resin, and foams in the polymer composition at or near the melting temperature of the composition. Any suitable foaming agent is preferably selected in consideration of the melting temperature, melt viscosity, and other physical properties of the polymer.

Typical inorganic foaming agents that can be used in the present invention include, for example, sodium bicarbonate (sodium bicarbonate), ammonium bicarbonate, ammonium carbonate and the like, and organic foaming agents include N, N ′. -Dinitroso pentamethylene tetramine (DPT), azodicarbonamide (ADCA), azobisisobutyronitrile, benzene sulfonyl hydrazide, 4,4'-oxybis (benzenesulfonyl hydrazide), toluene sulfonyl hydrazide, p -Toluene sulfonyl semicarbazide, barium azodicarboxylate, etc. can be mentioned.
Furthermore, so-called water foaming using water (water vapor) can be employed, and examples of the foaming agent used include water, inorganic substances containing crystal water, and hygroscopic resins (potassium ionomer, etc.).

  Such a foaming agent is, for example, uniformly mixed with a small amount of the same or similar polymer as the constituent polymer of the foamed resin layer such as polyethylene, and if necessary, an additive such as a foaming aid is blended into a master batch. Is sold as a commercial product (for example, Polyslen EE), and it is convenient to use it.

  The blending ratio of the foaming agent to the ethylene polymer composition varies depending on the type of foaming agent and polymer used, the thickness of the foamed layer to be formed, the foaming ratio, etc., and is appropriately determined in consideration of them. However, 100 ppm to 30% by weight is usually preferable with respect to 100 parts by weight of the resin. For example, when the polymer is an ethylene / methacrylic acid copolymer zinc ionomer and the foam layer thickness is about 100 μm and the expansion ratio is about 2 times, Polyslen EE205D (PE-based 20% concentration, carbon dioxide foaming inorganic foaming agent) foaming agent In general, about 2 to 5 parts by weight per 100 parts by weight of the composition is used.

  The laminated film or sheet of the present invention has a basic laminated structure in which a foamed resin layer is formed on one side of the base as described above, and an aspect in which the foamed layer is laminated on both sides of the base according to the application. Or a mode in which the foamed resin layer is sandwiched between two substrates.

Further, one or more resin layers not containing a foaming agent may be further laminated on the laminate, and the resin used for such a foaming agent-free resin layer can be laminated on the base material or the foamed layer resin. It is possible to use without particular limitation on the assumption, and specifically, the same resin as that used for the foamed layer can be mentioned.
In particular, it is preferable to select a resin having thermal adhesiveness to the resin within a melting point range capable of coextrusion with the foaming agent-containing resin composition.
For example, as a suitable example thereof, there can be mentioned an embodiment in which at least one layer made of an ethylene polymer not containing a foaming agent is further laminated.
For example, a layer of an ethylene polymer that does not contain a foaming agent is laminated on the surface of the foamed polymer layer of the above basic laminate structure, and further, a foaming agent-free ethylene system is also formed on the substrate surface side of the laminate of the structure. The thing etc. which laminated | stacked the polymer layer can be illustrated.

  Among these, in particular, the foaming agent-free thermoplastic resin layer is a transparent layer or a colored layer, and a resin layer not containing a foamed layer is laminated on one side of the foamed layer made of the thermoplastic resin composition. This embodiment is preferable in that the surface of the foam layer can be protected from abrasion damage and the decorative effects of the foam layer of the present invention can be more varied.

The following can be illustrated as a typical layer structure of the laminated film or sheet of the present invention.
1) Foam layer / base material 2) (Transparent) resin layer / foam layer / base material 3) Foam layer / base material / resin layer,
4) Foam layer / resin layer / base material,
5) (Transparent) resin layer / foamed layer / base material / resin layer,
6) (Transparent) resin layer / foamed layer / resin layer / substrate / resin layer,

Each thickness of the base material, the foamed layer, and the (non-foamed) resin layer in the laminated film or sheet of the present invention is not particularly limited, and the layer configuration, use, and other conditions of the laminated film or sheet However, in general, the substrate thickness is about 5 to 1000 μm, particularly 10 to 500 μm, and the thickness of the foam layer depends on the foaming ratio and the like, and varies within a considerable range. Generally, about 5 to 1000 μm, particularly 10 to 500 μm is preferable.
The thickness of the non-foamed resin layer is appropriately set according to the purpose of lamination, but is usually preferably about 3 to 100 μm.

As an apparatus for producing the laminated film or sheet of the present invention, for example, in the case where the layer constitution is a basic layer constitution comprising a foam layer and a substrate, an extruder with a die as shown in FIG. Extrusion laminator generally used for laminating a resin on a base material such as paper or PET can be used, but from the relationship of laminating a foamed resin layer, a cooling roll and a nip roll The gap is set slightly wider than in the case of lamination of non-foamed resin layers.
Moreover, when manufacturing the laminated film or sheet | seat of the aspect which consists of a foaming layer, a non-foaming resin layer, and a base material by coextrusion, the die part of the said extrusion laminator uses the laminator of a coextrusion die structure.

In the method for producing a laminated film or sheet of the present invention using the apparatus, the foam layer formation timing is adjusted mainly by the extrusion resin temperature, the extrusion laminator processing speed (take-off speed), the air gap, and the cooling roll. This is done by adjusting the gap of the nip roll.
These adjustments are appropriately made in consideration of the material of the laminated film or sheet to be manufactured, the size such as the thickness and width, the polymer material of the foamed layer, the type of foaming agent, the foaming ratio, the layer thickness, etc. Generally, the extrusion resin temperature is in the range of 150 to 300 ° C., the extrusion laminator processing (take-off) speed is in the range of 5 to 150 m / min, the air gap is in the range of 50 to 150 mm, the cooling roll It is preferable that the gap length between the nip roll and the nip roll is adjusted in the range of 0 to 2 mm.

The present invention will be specifically described by the following examples, but the present invention is not limited to these examples.
"Example 1"
A coextrusion laminator (extruder: 65 mmφ diameter, die: 850 mm width, cooling roll 600 mmφ, nip roll 250 mmφ) in which the die portion of the extrusion laminator shown in FIG. 1 is replaced with a coextrusion die is used. The gap was adjusted to about 0.1 mm and the air gap was set to 110 mm.
Also, a PET film (thickness 12 mm, width 500 mm, laminated side corona treatment) is used as a base material, and a foaming agent (polyethylene base coating) is added to a zinc ionomer (Himiran 1650) of an ethylene / methacrylic acid copolymer as a resin composition for a foam layer. 20% concentration master batch, carbon dioxide foaming: Polyslene EE205D) blended at 97.5 / 2.5 (weight ratio), and ethylene ion / methacrylic acid copolymer zinc ionomer (Himiran 1650) (foaming agent) (Not contained) was prepared.
Then, these are loaded into the respective predetermined loading locations of the coextrusion laminator so that the laminated structure is a base material / foam layer / (foaming agent-free) resin layer, the resin temperature is 260 ° C., and the processing (take-off) speed is Under the condition of 40 m / min, the resin composition for foamed layer and the resin (containing no foaming agent) were coextruded at a thickness of 20 μm, and extrusion foaming lamination was performed.

The obtained laminated film (Example product 1) has a foam layer thickness of 90 μm, a foaming ratio of 2.3 times, a foamed state is good, and contains an infinite number of fine elongated foam cell groups. As shown in FIG. 2, a striped streak pattern was formed on a frosted glassy translucent ground.
Moreover, the heat conductivity of this laminated film was 0.098 (W / m · k). The test method for thermal conductivity is as follows.
Test conditions Test equipment: GH-1 (Alpac Riko)
Measurement method: steady state thermal flow meter method Measurement temperature: 25 ° C
Sample size 50φ x sample thickness

“Examples 2 to 4”
Example 1 except that the processing (take-off) speed condition, roll gap, foam layer resin composition and foaming agent-free resin coextrusion thickness in Example 1 were changed to the conditions shown in Table 1, respectively. Extrusion foam lamination was performed in the same manner.
The results are shown in Table 1.

"Example 5"
The extrusion laminator (extruder: 65 mmφ diameter, die: 850 mm width, cooling roll 600 mmφ, nip roll 250 mmφ) shown in FIG. 1 is used, and the gap between the cooling roll and nip roll of the apparatus is about 0.1 mm and the air gap is 110 mm. Set, PET film (thickness 12 mm, width 500 mm, laminated side corona treatment) as a base material, ethylene / methacrylic acid copolymer zinc ionomer (Himiran 1650) as foaming layer resin composition, foaming agent (Polyslen EE205D) ) Was prepared at 99 / 1.0.
Then, these are loaded into a predetermined loading place of the extrusion laminator, and the above resin composition for the foam layer is extruded in a single layer at a thickness of 20 μm under the conditions of a resin temperature of 260 ° C. and a processing (take-off) speed of 80 m / min, and extrusion. Foam lamination was performed.
Table 1 shows the results of evaluation of the obtained laminated film (single-layer extrusion) in the same manner as in Example 1.

"Example 6"
In Example 1, the resin composition for a foam layer was prepared by adding a neutralization degree of an ethylene / methacrylic acid copolymer (methacrylic acid content: 15% by weight) to an ethylene / methacrylic acid copolymer zinc ionomer (High Milan 1650). Replacing with a composition in which mol% potassium ionomer is mixed at a ratio of 7/3 (weight ratio), the foaming is water foaming, the resin temperature is 280 ° C., and the processing (take-off) speed is 20 m / min. Extruded foam laminate was carried out in the same manner as in Example 1 except that the coextruded thickness of the product and the foaming agent-free ionomer resin was changed to 40 μm, and the obtained laminated film was evaluated in the same manner as in Example 1.
The results are shown in Table 1.

"Example 7"
In Example 1, the resin composition for the foam layer was changed to one in which a foaming agent (Polyslen EE205D) was blended at a ratio of 95 / 5.0 to a zinc ionomer (Himiran 1650) of an ethylene / methacrylic acid copolymer. Except for the above, extrusion foaming lamination was carried out in the same manner as in Example 1, and the obtained laminated film was evaluated in the same manner as in Example 1.
The results are shown in Table 1.

"Example 8"
Extrusion foam lamination was carried out in the same manner as in Example 7 except that the layer structure was changed to base material / resin layer / foamed layer, and the obtained laminated film was evaluated in the same manner as in Example 1.
The results are shown in Table 1.

The schematic diagram which shows an example of the extrusion foaming laminator for manufacturing the laminated | multilayer film or sheet | seat of this invention. The figure which shows an example of the pattern which appears on the foaming layer surface of the laminated | multilayer film or sheet | seat of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooling roll 2 Nip roll 3 T die 4 Base material 5 Flow path of molten polymer (foaming agent) 5 ′ manifold 6 Laminated film (sheet)
7 Air gap 8 Gap between rolls 10 Extrusion laminating machine a Foamed molten web

Claims (11)

  A laminated film or sheet comprising at least a base material and a thermoplastic resin foam layer, wherein the foam layer is foamed when the thermoplastic resin composition containing a foaming agent is extruded and laminated on the base material. A laminated film or sheet characterized by being a thing.   The laminated film or sheet according to claim 1, wherein at least one layer made of a thermoplastic resin containing no foaming agent is further laminated.   The laminated film or sheet is formed by coextrusion of at least one layer made of a thermoplastic resin containing no foaming agent and the foaming agent-containing thermoplastic resin composition on a base material. The laminated film or sheet according to claim 2.   The laminated film or sheet according to any one of claims 1 to 3, wherein a foaming ratio of the thermoplastic resin foam layer is 1.2 to 5 times.   The laminated film or sheet according to any one of claims 1 to 4, wherein the thermoplastic resin constituting the foamed layer comprises an ethylene polymer.   The foam layer contains innumerable fine elongated foam cell groups, and from the local density of the dispersion density of the foam cell groups, the appearance thereof exhibits a vertical stripe pattern on a cloudy glassy translucent ground. The laminated film or sheet according to any one of claims 1 to 5.   The laminated film or sheet according to claim 6, wherein the layer made of a thermoplastic resin not containing the foaming agent is a transparent layer or a colored layer, and is laminated on one surface side of the thermoplastic resin foam layer.   The foaming agent-containing thermoplastic resin composition is melt-extruded from an extrusion laminator die, and drawn through a gap between a cooling roll and a nip roll in a state where one side of the extruded molten web and one side of the substrate are overlapped. In the method for producing a laminated film or sheet having a step of thermally bonding and laminating both, the foaming agent-containing thermoplastic resin composition is discharged from the die until passing through the gap between the cooling roll and the nip roll. A method for producing a laminate, comprising foaming during a period to complete formation of a foam layer.   A foaming agent-containing thermoplastic resin composition and a resin or resin composition not containing a foaming agent were melt-coextruded from a die of a coextrusion laminator, and one side of the extruded molten web and one side of the substrate were overlapped. In a method for producing a laminated film or sheet having a step of passing through a gap between a cooling roll and a nip roll and then thermally bonding and laminating both, the foaming agent-containing thermoplastic resin composition exits the die. And a foaming layer formation is completed by foaming in a period from when the cooling roller and the nip roll pass through the gap between the cooling roll and the nip roll.   The method according to claim 8 or 9, wherein the foamed layer is formed by adjusting an extrusion resin temperature of an extrusion laminator, a processing speed, an air gap, and a gap length between a cooling roll and a nip roll.   The extrusion resin temperature is in the range of 150 to 300 ° C., the extrusion laminator processing speed is in the range of 5 to 150 m / min, the air gap is in the range of 50 to 150 mm, and the gap length between the cooling roll and the nip roll is in the range of 0 to 2 mm. The method of claim 10, each adjusted.

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