JPH11245356A - Laminate having surface-treated sealant layer, lid or label using the laminate, plastic container with the lid and / or label - Google Patents

Abstract

(57) [Summary] An object of the present invention is to provide a lid material excellent in sealing property, opening property and food hygiene.
Label with good sealability and excellent
Labels with excellent label adhesive strength and surface decoration
It is an object to provide a last container. A product having at least a sealant layer on a substrate
In the layered body, the sealant layer is a linear low-density polyethylene
And the sealant layer satisfies the following formula (1).
It is characterized by having been subjected to a surface oxidation treatment. Δ (O / C) ≧ 0.1 Equation (1) (However, △ (O / C) = (O / C)^S-(O / C)⁰so
Yes, here (O / C) ⁰And (O / C)^SIs the surface
Sealant surface and surface oxidation treatment when oxidation treatment is not performed
X-ray photoelectron on the treated sealant surface
Spectroscopically measured number of oxygen and carbon atoms
Represents the ratio. )

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate having a surface-treated sealant layer in a laminate comprising a base material and a sealant layer laminated thereon. The present invention relates to a label and a lid material and / or a plastic container with a label.

[0002]

2. Description of the Related Art As processed food containers, plastic injection molded containers and sheet molded containers are frequently used. Such a molded container is sealed by heat-sealing a lid material, and various heat-sealing techniques have been applied. Generally, the base material has a sealant layer on the base material, and as the base material of the lid material, aluminum foil, polyester (PET) / aluminum foil, paper / aluminum foil, and the like are often used.

[0003] Also, stretched polyester (OPET), stretched polypropylene (OPP), stretched nylon (ONy)
Are also used alone or laminated with a gas barrier film.

For the sealant layer, a hot melt is used in which an ethylene-vinyl acetate copolymer (EVA) is blended with a wax and a tackifier such as rosin or petroleum resin.

[0005] Further, a resin obtained by extruding and coating a resin obtained by blending a tackifier with EVA,
A film obtained by forming a blended resin into a film and dry laminating the film to a substrate is also used.

Examples of the material of the container include expanded polystyrene typified by a cup ramen container, polyester, polystyrene, and polypropylene such as those found in food cup containers such as jelly and yogurt. There is also a container in which polyethylene is laminated on the innermost layer of a paper container, and a material suitable for the material of the container is selected as the sealant layer of the lid.

In general, there is no polymer having good adhesion to containers such as expanded polystyrene and polyester.
For the sealant layer of the lid material, it is essential to add a tackifier to increase the adhesiveness. However, since tacky fire is a low molecular weight component, there is a hygienic limitation in its use as a packaging material for food, and it is difficult to balance the adhesive strength with the container and hygiene. there were.

[0008] In recent years, instead of a glass container, lightweight
Plastic containers with good moldability are widely used. In general, a printed layer or a label is attached to the outer surface of the container in order to provide the display and aesthetics of the contents and products.

[0009] As a conventional label sticking method, after forming a container, an adhesive is applied to the side to be bonded of the label and then attached to the container, or a label having an adhesive applied to the surface to be bonded in advance is used. Although it was affixed to the container, the label was affixed in the process after the container was formed, so that the work efficiency was very poor and it took a long time. Further, at present, a method of attaching a label having an adhesive layer at the same time as molding a container is performed at the time of molding the container. However, the adhesive of this adhesive layer is
Mainly because it is a hot lacquer type or hot melt type adhesive that is mainly composed of ethylene vinyl acetate resin and is generally used as an adhesive for heat sealing, the material of the container, for example, a container made of polyethylene terephthalate resin In this case, there is a problem that the label is not simultaneously attached at the time of molding the container.

[0010]

In view of the above problems, the present invention relates to a lid material having good sealing properties, good openability and excellent food hygiene and a material of a plastic container to be adhered. It is an object of the present invention to provide a label having good sealability without performing the method, and to provide a plastic container with a label having better label adhesive strength and surface decoration than conventional plastic containers with a label.

[0011]

The present invention solves the above-mentioned problems.
The invention according to claim 1 has been devised to solve the problem.
Is a laminate made by laminating at least a sealant layer on a substrate
In the body, whether the sealant layer is linear low density polyethylene
And the sealant layer satisfies the following formula (2)
It is characterized by having been subjected to a surface oxidation treatment. Δ (O / C) ≧ 0.1 Equation (2) (However, Δ (O / C) = (O / C)^S-(O / C)⁰so
Yes, here (O / C) ⁰Is a place where surface oxidation treatment is not performed.
X-ray photoelectron spectroscopy
Represents the ratio of the specified number of oxygen atoms to carbon atoms, and (O
/ C)^SIndicates that the sealant surface has been
And carbon atoms measured by X-ray photoelectron spectroscopy
Represents the ratio of the number of each atom. )

According to a second aspect of the present invention, in the laminate having the surface-treated sealant layer according to the first aspect, the linear low-density polyethylene includes butene-1, hexene-1, octene-1,4-methylene. It is a copolymer of ethylene and a comonomer selected from Lupentene-1.

[0013] The invention according to claim 3 is the invention according to claim 1 or 2.
In the laminate having the sealant layer subjected to the surface treatment as described above, the linear low-density polyethylene is synthesized using a single-site catalyst.

The invention according to claim 4 is the invention according to claims 1 to 3
In the laminate having the sealant layer subjected to the surface treatment as described above, the linear low-density polyethylene has a density of 0.
860 g / cm ³ or more and 0.925 g / cm ³ or less.

[0015] The invention according to claim 5 is the invention according to claims 1 to 4.
In the laminate having a sealant layer subjected to the surface treatment according to the above, the surface treatment of the sealant layer is any one of a corona discharge treatment, an ozone treatment, a plasma treatment, an electron beam irradiation treatment, an ultraviolet irradiation treatment, and a flame treatment. The processing is performed by a processing method.

According to a sixth aspect of the present invention, there is provided a laminate having a surface-treated sealant layer according to any one of the first to fifth aspects, wherein at least a surface of the sealant layer to be adhered to a container or the like is subjected to a surface treatment. Cover or label for the container.

According to a seventh aspect of the present invention, there is provided a plastic container having a lid and / or a label according to the sixth aspect.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. First, the X-ray photoelectron spectroscopy referred to in the present invention means ESCA (electron spectroscopy for ch
emical analysis) or XPS (X-ray photoel)
This is also referred to as "ectron spectroscopy", and is a spectroscopy using photoelectrons generated by irradiating a substance with X-rays. For (O / C), the abundance ratio of oxygen and carbon (O / C) is determined from the ratio of the value obtained by multiplying the area of each peak intensity of O _ls and C _ls by the relative sensitivity of each peak. In this measurement, the angle at which the film is irradiated with X-rays can be changed in the range of 0 to 90 degrees.
Is a value measured at an irradiation angle of 90 degrees.

The change with time of △ (O / C) will be described. The value of △ (O / C) immediately after the surface treatment tends to decrease over time. This is presumed to be due to the fact that the oxides and oxidatively active species are buried in the film over time. △ (O / C) in the present invention
Is 0.1 or more, preferably 1.0 or more.
If the value of Δ (O / C) is smaller than 0.1, sufficient adhesive strength cannot be obtained.

The density of the linear low-density polyethylene in the present invention is selected from the range of 0.860 to 0.925 g / cm3, preferably 0.880 to 0.910 g / cm3. If the density is less than 0.860 g / cm3, the laminate laminated with the base material is undesirably blocked, and if the density is more than 0.925 g / cm3, good adhesiveness cannot be obtained.

The linear low-density polyethylene of the present invention is selected from those having a melt flow rate at 190 ° C. and a load of 2160 g in the range of 1 to 30 g / 10 min. Further, it is desirable that the value of Mw / Mn measured by GPC is usually 1.0 or more and 5.5 or less, preferably 4.5 or less, and more preferably 3.5 or less.

The linear low-density polyethylene in the present invention includes a linear low-density polyethylene synthesized by a multi-site type catalyst represented by a Ziegler type catalyst and a single-site low density polyethylene represented by a metallocene catalyst. Although a linear low-density polyethylene synthesized with a system catalyst can be used, it is more preferable to use a linear low-density polyethylene synthesized with a single-site catalyst. Further, these linear low-density polyethylenes may be blended and used.

The single-site catalyst is not particularly limited, but is exemplified by a cyclopentadienyl zirconocene derivative and a transition metal such as Zr, Ti, Hf and the like, such as a cyclopentadienyl ring and an indenyl ring. A so-called metallocene catalyst comprising a saturated ring is exemplified.

Another example of the single-site catalyst is a single-site catalyst obtained by improving a conventional Ziegler-Natta catalyst, and has a ratio Mw between the weight average molecular weight and the number average molecular weight of the polymer. / Mn is preferably 1.
Those having a value of 0 or more and 3.5 or less can be used.

The comonomer of the linear low-density polyethylene in the present invention may be any one selected from butene-1, hexene-1, octene-1,4-methyl-pentene-1, etc., butene-1, hexene-1, octene-1. Is preferred because of its low cost.

The above-mentioned linear low-density polyethylene 100
If necessary, 100 parts by weight or less, preferably 50 parts by weight or less, more preferably 20 parts by weight or less of low-density polyethylene may be added as required.

Further, additives such as an antioxidant, a lubricant, an antiblocking agent, an antistatic agent, and an antifogging agent can be added to the linear low-density polyethylene as required.

As a method of oxidizing the surface of the sealant, chemical treatment such as ozone treatment, corona discharge treatment,
It is performed by physical treatment such as plasma treatment, electron beam irradiation treatment, ultraviolet irradiation treatment, and flame treatment. In addition, as a chemical treatment method, a method of oxidizing the surface of the sealant using a strong acid such as a chromic acid mixed solution can be performed. However, it is not preferable in view of workability and environmental compatibility.

Next, a description will be given of a cover material or a label formed of a laminate having a surface treatment-treated sealant layer of the present invention.

When the ozone treatment is used, when the linear low-density polyethylene extruded by the T-die method is in a molten state, one or both sides of the linear low-density polyethylene are surface-treated using a known ozone treatment apparatus. Laminate while extruding directly onto the substrate so that the treated surface becomes the surface to be adhered to the container or the like. Alternatively, after laminating an ozone-treated film, dry lamination may be performed so that the treated surface is a surface to be adhered to a container or the like.

When corona discharge treatment is used, a linear low-density polyethylene film formed by a T-die method or an inflation method is subjected to a corona discharge treatment on one or both sides to perform a surface treatment. Dry lamination is performed on one side of the base material so as to be a surface to be bonded to the base material. Alternatively, after laminating while directly extruding onto the substrate, the surface to be bonded may be subjected to corona discharge treatment.

The same applies to the case of using a plasma treatment, an electron beam irradiation treatment, an ultraviolet irradiation treatment, and a flame treatment. A linear low-density polyethylene film formed by a T-die method or an inflation method is subjected to a surface treatment on one or both sides thereof. Dry laminating on one side of the base material so that the surface treated surface becomes the surface to be adhered to the container or the like, or laminating while directly extruding onto the substrate, then performing surface treatment on the surface to be adhered. Is also good.

The plasma treatment is carried out in a simple substance or a mixed gas of argon, helium, neon, xenon, hydrogen, nitrogen, oxygen, ethylene, air, etc., utilizing a discharge phenomenon and a glow discharge. That is, the surface of the linear low-density polyethylene film is treated with active species such as generated ions, radicals, excited species, and electrons.

The electron beam irradiation is performed by irradiating the surface of linear low density polyethylene with an electron beam generated by an electron beam accelerator. As the irradiation dose,
It is performed in the range of 1 to 200 kGy, and if it exceeds this range, the surface may be crosslinked and the adhesiveness may be reduced.

The ultraviolet irradiation is a step of irradiating ultraviolet rays in an air atmosphere to generate atomic oxygen and oxidize the film surface. In this ultraviolet irradiation, ultraviolet rays of 180 to 400 nm are used, but when ultraviolet rays of about 185 nm and about 255 nm are used together, the oxidation treatment effect is improved.

For the flame treatment, air or oxygen,
A natural gas such as methane, propane or butane is sprayed on the film in a completely burned state to treat the surface. Flame treatment is generally used for thick materials such as blows and injection molded products.However, by passing the film over a sufficiently cooled plated metal drum and blowing the flame on the opposite surface, Surface treatment of the film can be performed.

These surface treatments are described in JIS K67.
68, that is, by using a mixture prepared by mixing formamide and ethylene glycol monoethyl ether at a specified ratio as a standard solution, the treatment state can be easily confirmed. In other words, when the standard film is applied to the sample surface and the liquid film is kept applied on the sample surface for 2 seconds or more without interruption, it is judged as "wet" and the sample surface is determined to be "wet". Wet out of the standard solution,
When the wetting index is 32 dyn / cm or more, with the value of the formamide having the highest proportion as the wetting index, it can be determined that the surface treatment has been performed.

As the base material for using the laminate having the surface treatment-treated sealant layer of the present invention as a lid, aluminum foil, polyethylene terephthalate / aluminum foil,
Paper / aluminum foil, biaxially oriented polypropylene film, biaxially oriented polyester, biaxially oriented nylon film and the like can be used.

As the material of the container to be bonded to the lid material in the present invention, polyester, polypropylene, polystyrene, polyethylene and the like can be mentioned, and further, these foams may be used. Good adhesiveness is obtained for any of the materials.

The base material for the label using the laminate having the surface treated sealant layer of the present invention as a label is not particularly limited, but may be paper, stretched polyester, or the like.
Stretched polypropylene, aluminum foil, and the like are common, and these may be laminated.

The structure of the label of the present invention is not particularly limited, either, but the following (a), (b),
The layer configuration of (c) is mentioned. (A) Varnish coat layer / Picture layer / Paper layer / Sealant layer structure (B) Varnish coat layer / Picture layer / Synthetic paper layer / Sealant layer structure (C) Base layer / Picture layer / Adhesive layer structure As the paper used for the paper layer, normal art paper, coated paper, or the like can be used. In the above (b), synthetic paper is also used as ordinary synthetic paper (for example, YUPO,
Synthetic paper such as peach coat) is used. In the above (c), the substrate layer is made of a plastic film, and more desirably, an unstretched polypropylene film, or a stretched polypropylene film, a stretched polyester film, or a stretched nylon film.

Further, specific structures of the label of the present invention include the following layer structures (d), (e), (f), (g), and (h). (D) Configuration of base layer / design layer / aluminum foil layer / sealant layer (e) Base layer / design layer / aluminum deposited film layer /
Sealant layer configuration (f) Base layer / Picture layer / Aluminum-deposited paper layer / Sealant layer configuration (G) Base layer / Picture layer / Aluminum-deposited synthetic paper layer / Sealant layer configuration (H) Base layer / Picture layer / Aluminum vapor deposited layer / sealant layer constitution The base layer used in each constitution is composed of a plastic film, and more desirably, an unstretched polypropylene film, a stretched polypropylene film, a stretched polyester film, or a stretched polyester film. Made of nylon film. Further, in the above (e),
The aluminum-deposited film used for the aluminum-deposited film layer is a plastic film, such as a polypropylene film or a polyester film. In the above (f), as the aluminum-deposited paper used for the aluminum-deposited paper layer, ordinary art paper, coated paper, or the like can be used. For example, synthetic paper such as YUPO or peach coat) is used.

Examples of the material of the plastic container to which the label is to be attached include polyester such as polyethylene terephthalate and polyethylene naphthalate, polyolefin such as polyethylene and polypropylene, polystyrene, polyvinyl chloride, polycarbonate, polyamide, and high nitrile resin. Can be used. Preferably, use of polypropylene, polyethylene terephthalate, or polyethylene naphthalate is desirable. Further, the material of these plastic containers may have a single layer or a multilayer structure.

<Action> Although the details of the reason why the adhesiveness is developed are not well understood, an oxidized layer is formed on the surface of the linear low-density polyethylene film by oxidizing the surface thereof, and the oxidized oxide or It is presumed that a strong sealing property with the container is obtained by the action of the active oxidizing species. In particular, when linear low-density polyethylene polymerized with a single-site catalyst is used, oxides and oxidatively active species are effectively used because low-molecular-weight components that elute largely near the surface under high-temperature melting are small. It is presumed that stronger sealing strength can be obtained because of the work.

[0045]

EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited to the following examples.

Example 1 A polyester film which is a biaxially stretched film (thickness: 25 μm; Espet E510)
0; manufactured by Toyobo Co., Ltd.) and low-density polyethylene (density: 0.919 g / cm3; Mirason 14P; manufactured by Mitsui Chemicals, Inc.) with a thickness of 20 μm was used as a base material. On the low-density polyethylene side of the base material, a linear low-density polyethylene (density: 0.910; Moortec 1014D)
1; Idemitsu Chemical Co., Ltd.) at a thickness of 25 μm and 280 ° C.
To form a sealant layer on the substrate. Then, 50 W / m2 / mi is applied to the surface of the sealant layer.
The surface treatment was performed by a corona discharge treatment having a treatment strength of n to produce the lid material of the present invention. △ (O / C) at this time
Was 7.0 as a result of measurement by X-ray photoelectron spectroscopy.

<Example 2> On the same base material as in Example 1,
The same linear low-density polyethylene (density;
910; Moretec 1014D1; Idemitsu Chemical Co., Ltd.)
Is discharged at 280 ° C. with a thickness of 25 μm, a sealant layer is formed on the base material, and at the same time, an ozone gas having a concentration of 40 g / Nm 3 is discharged on the surface of the sealant layer to oxidize the surface, thereby forming a cover material of the present invention. Was prepared. At this time
(O / C) was measured by X-ray photoelectron spectroscopy and found to be 6.2.

<Example 3> A linear low-density polyethylene (density 0.902 g / cm3; PT1450; manufactured by Dow) polymerized by a single-site catalyst on the same base material as in Example 1 was applied to a thickness of 25 µm. Extrusion was performed at 280 ° C. to form a sealant layer on the substrate. Then, the surface of the sealant layer was subjected to plasma surface treatment in a mixed gas of helium gas and ethylene gas to produce a lid material of the present invention. △ (O / C) at this time was 12.5 as a result of measurement by X-ray photoelectron spectroscopy.

Example 4 On the same substrate as in Example 1,
Linear low-density polyethylene polymerized by the same single-site system as in Example 3 (density 0.902 g / cm3; P
T1450; Dow) at a thickness of 25 μm and 280 ° C.
To form a sealant layer on the substrate. Then, an irradiation dose of 20 kGy is applied to the surface of the sealant layer.
The surface treatment was performed to produce a lid material of the present invention. At this time, △ (O / C) was determined by X-ray photoelectron spectroscopy to be 14.1.

<Example 5> On the same substrate as in Example 1,
Linear low-density polyethylene polymerized by the same single-site system as in Example 3 (density 0.902 g / cm3; P
T1450; Dow) at a thickness of 25 μm and 280 ° C.
To form a sealant layer on the substrate. 185 nm and 254 nm are applied to the surface of the sealant layer.
Ultraviolet rays were also irradiated for 30 seconds to produce the lid material of the present invention. △ (O / C) at this time was 5.1 as a result of measurement by X-ray photoelectron spectroscopy.

<Example 6> On the same base material as in Example 1,
Linear low-density polyethylene polymerized by the same single-site system as in Example 3 (density 0.902 g / cm3; P
T1450; Dow) at a thickness of 25 μm and 280 ° C.
To form a sealant layer on the substrate. Then, the surface of the sealant layer was subjected to a flame treatment to prepare a lid material of the present invention. △ (O / C) at this time was 15.7 as a result of measurement by X-ray photoelectron spectroscopy.

<Comparative Example 1> A lid material was produced in the same manner as in Example 1 except that the surface of the sealant layer was not subjected to the surface treatment by corona discharge treatment in Example 1.

Comparative Example 2 A lid material was produced in the same manner as in Example 1 except that the surface of the sealant layer was not subjected to the plasma surface treatment in Example 3.

Each of the lid members produced in Examples 1 to 6 and Comparative Examples 1 and 2 has a width of 15 mm.
Of polystyrene paper (PSP) with an expansion ratio of 12 times and injection-molded polyester (PE)
T) The plate was heat-sealed at 150 ° C., and the heat-sealing strength was measured. The results shown in Table 1 were obtained. From this result, it became clear that the lid material of the present invention has excellent heat sealing strength.

[0055]

[Table 1]

<Example 7> On a pattern layer side of a base material having an unstretched polypropylene film / pattern layer structure, Mooretec 1014 manufactured by Idemitsu Chemical Co., Ltd., which is a linear low-density polyethylene.
D1 (density 0.910) at a thickness of 25 μm at 280 ° C.
To form a sealant layer on the substrate. Then, 50 W / m2 / mi is applied to the surface of the sealant layer.
The surface treatment was performed by a corona discharge treatment having a treatment strength of n to produce the label of the present invention. △ (O / C) at this time
Was 7.0 as a result of measurement by X-ray photoelectron spectroscopy.

<Example 8> On the same base material as in Example 7,
The same linear low-density polyethylene as in Example 7, Moitec 1014D1 manufactured by Idemitsu Chemical Co., Ltd. (density 0.91
0) is discharged at 280 ° C. with a thickness of 25 μm, a sealant layer is formed on the substrate by lamination, and at the same time, an ozone gas having a concentration of 40 g / Nm 3 is discharged on the surface of the sealant layer to oxidize the surface. A label was made. At this time, △ (O / C) was 6.2 as a result of measurement by X-ray photoelectron spectroscopy.

<Example 9> A kernel 57L manufactured by Nippon Polychem Co., Ltd., which is a linear low-density polyethylene polymerized on a substrate similar to that of Example 7 with a single-site catalyst.
(Density 0.905) was extruded and laminated at 290 ° C. with a thickness of 25 μm to form a sealant layer on the substrate. Then, the surface of the sealant layer was subjected to plasma surface treatment in a mixed gas of helium gas and ethylene gas to produce a label of the present invention. △ (O / C) at this time was 10.6 as a result of measurement by X-ray photoelectron spectroscopy.

<Example 10> Nippon Polychem Co., Ltd., which is a linear low-density polyethylene polymerized on the same base material as in Example 7 by the same single-site system as in Example 9
57L (density 0.905) manufactured by Extruder Co., Ltd. was extruded and laminated at 290 ° C. with a thickness of 25 μm to form a sealant layer on the substrate. Then, the surface of the sealant layer was subjected to a surface treatment at an irradiation dose of 20 kGy to produce a label of the present invention. △ (O / C) at this time was 12.1 as measured and obtained by X-ray photoelectron spectroscopy.

<Example 11> Nippon Polychem Co., Ltd., which is a linear low-density polyethylene polymerized on the same base material as in Example 7 by the same single-site system as in Example 9
57L (density 0.905) manufactured by Extruder Co., Ltd. was extruded and laminated at 290 ° C. with a thickness of 25 μm to form a sealant layer on the substrate. Then, 185 is applied to the surface of the sealant layer.
The ultraviolet rays of 30 nm and 254 nm were irradiated for 30 seconds to produce the label of the present invention. △ (O / C) at this time was 4.7 as a result of measurement by X-ray photoelectron spectroscopy.

Comparative Example 3 A label was produced in the same manner as in Example 7 except that the surface of the sealant layer was not subjected to the surface treatment by corona discharge treatment in Example 7.

<Comparative Example 4> A label was produced in the same manner as in Example 7, except that the surface of the sealant layer was not subjected to the plasma surface treatment in Example 9.

Using the extrusion blow molding machine having one screw extruder, each of the labels prepared in Examples 7 to 11 and Comparative Examples 3 and 4 was used.
At the same time as the container was molded, it was simultaneously adhered to the surface of a container made of polyethylene terephthalate resin to form a labeled bottle having a body thickness of 750 μm and an internal volume of 800 ml. Then, in order to measure the adhesive strength between the label and the polyester container, cut out into a strip having a width of 15 mm, and use Tensilon UT
When the adhesive strength was measured using M500 (manufactured by Orientec), the results in Table 2 were obtained. From this result, it became clear that the label of the present invention has excellent adhesive strength.

[0064]

[Table 2]

[0065]

According to the present invention, by applying a surface treatment to the sealant layer, a tackifier for increasing the adhesiveness is not added, and a good adhesiveness with a container made of expanded polystyrene, polyester or the like is obtained. In addition, it is possible to provide a lid material which is easy to process, has good sealing properties with the container, and does not contain a low molecular weight component such as tackifier and is excellent in hygiene. In addition, by applying a surface treatment to the sealant layer, it is possible to provide a label exhibiting excellent adhesive strength with a plastic container, and furthermore, it is possible to provide an extrusion blow molding method, a stretch blow molding method, an injection molding method, or a vacuum or a sheet. In a pressurized air method or the like, it is possible to obtain a labeled plastic container having good adhesiveness and excellent surface decorativeness by simultaneously attaching a label during container molding.

Continuation of the front page (72) Inventor Hideo Fukushima 1-5-1, Taito, Taito-ku, Tokyo Letterpress Printing Co., Ltd.

Claims (7)

[Claims] (1) laminating at least a sealant layer on a substrate
In the laminate, the sealant layer is a linear low-density polyether
The sealant layer is made of styrene and has the following formula (1)
A surface characterized by a surface oxidation treatment that satisfies
A laminate having a treated sealant layer. Δ (O / C) ≧ 0.1 Expression (1) (However, Δ (O / C) = (O / C)^S-(O / C)⁰so
Yes, here (O / C) ⁰Is a place where surface oxidation treatment is not performed.
X-ray photoelectron spectroscopy
Represents the ratio of the specified number of oxygen atoms to carbon atoms, and (O
/ C)^SIndicates that the sealant surface has been
And carbon atoms measured by X-ray photoelectron spectroscopy
Represents the ratio of the number of each atom. ) 2. The linear low-density polyethylene is a copolymer of ethylene with a comonomer selected from butene-1, hexene-1, octene-1,4-methyl-pentene-1. A laminate having the sealant layer subjected to the surface treatment according to 1. 3. The laminate having a surface-treated sealant layer according to claim 1, wherein the linear low-density polyethylene is synthesized by a single-site catalyst. 4. The linear low-density polyethylene has a density of:
The laminate having a surface-treated sealant layer according to any one of claims 1 to ^{3, wherein the} thickness is 0.860 g / cm ³ or more and 0.925 g / cm ³ or less. 5. The surface treatment of the sealant layer includes a corona discharge treatment, an ozone treatment, a plasma treatment, an electron beam irradiation treatment,
The laminate having a surface-treated sealant layer according to any one of claims 1 to 4, wherein the laminate is treated by any one of an ultraviolet irradiation treatment and a flame treatment. 6. A laminate having a surface-treated sealant layer according to claim 1, wherein at least a surface of the sealant layer to be adhered to a container or the like is subjected to a surface treatment. Container lid or label. 7. A plastic container with a lid and / or a label according to claim 6.