JPH0839740A - Cover material - Google Patents

Abstract

PURPOSE:To provide a cover material having high adhesion to a polypropylene resin container and excellent release property from it at low cost. CONSTITUTION:In a cover material 1, a biaxially stretching resin layer 2, a heat sealant layer 6, and a release layer 5 arranged adjacently to the heat sealant layer 6 and in between the biaxially stretching resin layer 2 and the heat sealant layer 6 are provided. An intermediate layer 4 is arranged adjacently to the release layer 5 and in between the biaxially stretching resin layer 2 and the release layer 5. The heat sealant layer is made of ethylene vinyl acetate as a main component.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lid material, and more particularly to a lid material used for polypropylene resin containers.

[0002]

2. Description of the Related Art Conventionally, various parts, solid or liquid foods, and the like are housed in a synthetic resin container, and the opening is sealed with a lid member for distribution and storage.

For example, an electronic component is housed in each embossed portion of a carrier tape on which a large number of embosses are formed, and a lid material (cover tape) is heat-sealed and sealed on the carrier tape so as to cover the embossed portion. Carrier type taping is used. The carrier tape used for such embossed carrier type taping is usually formed of a material such as polyvinyl chloride, polystyrene, polyester, polypropylene, etc., which can be easily formed into a sheet. The lid member also includes a biaxially stretched resin film and a heat sealant layer formed on one surface of the film. Then, in the electronic component mounting process, the lid member is required to be peelable in order to take out the electronic component housed in the embossed carrier type taping.

Further, in the embossed carrier type taping in which the lid material is heat-sealed, it is inspected at the final stage of shipment whether or not the electronic parts are filled, and the appearance and function of the electronic parts are defective (lead bending, bending, It is necessary to visually check the voids in the packaging part).

[0005]

However, the heat-sealing of the lid member to the carrier tape is performed so that the lid member does not peel off during the transportation and storage of the embossed carrier type taping, and the electronic component does not drop off. , A predetermined strength is required, but if this heat fusion strength is too large, the carrier tape vibrates and the electronic component pops out from the embossed portion of the carrier tape when the lid material is peeled off in the mounting process of the electronic component. There was a problem that an accident occurred. In particular, in polypropylene type carrier tapes, many of those conventionally used as a lid material are those in the form of peeling (interfacial peeling) at the interface between the lid material and the carrier tape. The change in peel strength and the change in peel strength due to the sealing condition were unavoidable.

That is, the lid material used for the polypropylene type carrier tape is also required to be adhered to the carrier tape with sufficient strength and have good peeling property when using electronic parts. However, the conventional interfacial peeling type cover material has a problem that good peelability cannot be obtained from the polypropylene type carrier tape.

Since the lid material is discarded after being peeled from the carrier tape, the cost of the lid material is required to be as low as possible, and the manufacturing cost is reduced by reducing the raw material cost without deteriorating the peeling property. Is required.

The present invention has been made in view of such circumstances, and an object thereof is to provide an inexpensive lid member having both high adhesiveness to a polypropylene resin container and good peelability.

[0009]

In order to achieve such an object, the present invention provides a biaxially stretched resin layer, a heat sealant layer, and the biaxially stretched resin layer and the heat layer adjacent to the heat sealant layer. A release layer located between the release layer and a sealant layer, and an intermediate layer adjacent to the release layer and located between the biaxially stretched resin layer and the release layer, wherein the heat sealant layer comprises ethylene-vinyl acetate. The structure is such that the main component is included. Further, the heat sealant layer is formed in a sea-island pattern on one surface of the lid member, and the area of one sea-island pattern is set to 0.01 to 0.5 mm ² .

[0010]

The lid member includes a biaxially stretched resin layer, a heat sealant layer containing ethylene-vinyl acetate as a main component, and a release layer adjacent to the heat sealant layer between the biaxially stretched resin layer and the heat sealant layer. And having an intermediate layer adjacent to the release layer and between the biaxially stretched resin layer and the release layer, peelable between the release layer and the intermediate layer, or cohesive failure in the release layer or Since it is possible to peel between the peeling layer and the heat sealant layer, the lid material has high adhesiveness to the polypropylene resin carrier tape due to the heat sealant layer, and the heat fusion between the carrier tape and the heat sealant layer is high. The lid material can be peeled off stably and reliably regardless of the attachment strength. Further, by forming a heat sealant layer on one surface of the lid material in a sea-island pattern,
Since the heat sealant layer material can be reduced, the manufacturing cost can be kept low.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view of the lid member of the present invention.
In FIG. 1, a lid material 1 includes a biaxially stretched resin layer 2 and an adhesive layer 3.
An intermediate layer 4 sequentially laminated on the biaxially stretched resin layer 2 via
A release layer 5 and a heat sealant layer 6 are provided.

The biaxially stretched resin layer 2 can be formed of a biaxially stretched film such as a polyester resin such as polyethylene terephthalate (PET), a polyolefin resin such as polypropylene, a polyamide resin such as nylon and a polycarbonate resin. By providing the biaxially stretched resin layer 2 in this way, heat resistance can be imparted to the lid material 1. The thickness of the biaxially stretched resin layer 2 can be appropriately set according to the purpose of use of the lid material, and can be set to, for example, about 6 to 100 μm. If necessary, the surface of the biaxially stretched resin layer 2 on which the adhesive layer 3 is formed is previously corona treated,
Surface treatment such as plasma treatment or sandblast treatment may be performed to enhance the adhesiveness with the adhesive layer 3. In addition, a material that has been subjected to static electricity generation prevention processing as needed can also be used.

The adhesive layer 3 is made of low density polyethylene, ethylene-α / olefin copolymer having a density of 0.915 to 0.940 g / cm ³ , polyethylene vinyl acetate copolymer, ionomer, polypropylene, ethylene methacrylic acid copolymer. , Ethylene acrylic acid copolymer, or modified products thereof, such as polyolefin-based, polyethyleneimine-based, polybutadiene-based, organic titanium compounds, isocyanate-based, urethane-based adhesives, etc. The thickness is preferably about 0.2 to 60 μm. The adhesive layer 3 can be applied or extruded on a biaxially stretched resin film.
The intermediate layer 4 can be dry laminated or extruded laminated on top.

The intermediate layer 4 has a single layer structure and a density of 0.91.
5 to 0.940 g / cm ³ of ethylene-α / olefin copolymer, 50 to 90% by weight of styrene and 50 to butadiene
Styrene-butadiene block copolymer with 10 wt%, styrene 10-50 wt% and butadiene 90-50
It can be formed from three or more kinds of resins containing at least an ethylene-α-olefin copolymer and a styrene-butadiene block copolymer among hydrogenated products of styrene-butadiene block copolymer and high-impact polystyrene in an amount of 1% by weight. it can. The ethylene-α-olefin copolymer used for forming the mid layer 4 is ethylene,
For example, butene, pentene, hexene, heptene, octene, a copolymer with 4-methylpentene-1 and the like. The density of such ethylene-α-olefin copolymer is less than 0.915 g / cm ³ , or 0.940 g / cm ^3.
When it exceeds cm ³ , it is not preferable because the film forming property of the intermediate layer 4 due to the combination with the styrene-butadiene block copolymer is lowered.

When the amount of styrene constituting the styrene-butadiene block copolymer used for forming the intermediate layer 4 is less than 50% by weight, the tackiness of the film increases and handling becomes difficult. When it exceeds the above range, the adhesion to the release layer at low temperature becomes poor, which is not preferable.

Then, the ethylene-α.multidot.
The mixing ratio of the olefin copolymer and the styrene-butadiene block copolymer greatly influences the peel strength when the lid material 1 is heat-sealed to the polypropylene resin container and then peeled off, and the transparency of the lid material 1. To do. In the present invention, the mixing ratio of the ethylene-α-olefin copolymer and the styrene-butadiene block copolymer in the mid layer 4 is ethylene-α.
-Olefin copolymer 30 to 70% by weight and styrene-butadiene block copolymer 70 to 30% by weight. The amount of ethylene-α / olefin copolymer is less than 30% by weight,
When the content of the styrene-butadiene block copolymer is more than 70% by weight, the film forming property of the intermediate layer 4 is lowered, the transparency of the lid material is also lowered, and the adhesive force between the intermediate layer 4 and the peeling layer 5 is too large. However, the peeling strength of the lid material exceeds the suitable strength described below, which is not preferable. On the other hand, when the amount of the ethylene-α / olefin copolymer exceeds 70% by weight and the amount of the styrene-butadiene block copolymer is less than 30% by weight, the intermediate layer 4
The adhesion between the peeling layer 5 and the peeling layer 5 is too small, and the peeling strength of the lid material is less than the appropriate strength, which is not preferable.

When the intermediate layer 4 is formed of four kinds of resins using a hydrogenated product of a styrene-butadiene block copolymer and high-impact polystyrene, 30 to 70% by weight of the above ethylene-α-olefin copolymer is used. %
And a styrene-butadiene block copolymer 70-30
5 parts by weight of the styrene-butadiene block copolymer hydrogenated product of 10 to 50% by weight of styrene and 90 to 50% by weight of butadiene is added to 100 parts by weight of the resin composition.
Add ~ 30 parts by weight and add high impact polystyrene to 5
It is preferable to add about 50 parts by weight.

If the hydrogenated content of the styrene-butadiene block copolymer is less than 5 parts by weight, styrene-
The effect of adding the hydrogenated product of the butadiene block copolymer is not exhibited, and when it exceeds 30 parts by weight, the blocking resistance of the obtained film is insufficient, which is not preferable. When the hydrogenated product of the styrene-butadiene block copolymer is not actually a hydrogenated product, this copolymer has a high butadiene content, so that it is easily oxidized and the intermediate layer 4 is easily oxidized. Gel is likely to be generated during formation.

Further, when an anhydrous additive is used, the film forming accuracy may be poor and it may be difficult to form a film.

When the amount of high-impact polystyrene added is less than 5 parts by weight, the effect of adding high-impact polystyrene is not exhibited, and when it exceeds 50 parts by weight, the adhesive strength between the intermediate layer 4 and the peeling layer 5 is high. Is too large, and the peel strength of the lid material exceeds the appropriate strength, which is not preferable.

The intermediate layer 4 is made of ethylene-α.
To 100 parts by weight of the resin composition of 30 to 70% by weight of the olefin copolymer and 70 to 30% by weight of the styrene-butadiene block copolymer, 5 to 5 parts of the hydrogenated product of the styrene-butadiene block copolymer is used. It may be formed by a resin composition containing 30 parts by weight of three kinds of resins. Further, ethylene-α / olefin copolymer 30-
Resin containing three kinds of resins by adding only 5 to 50 parts by weight of high-impact polystyrene to 100 parts by weight of a resin composition of 70% by weight and styrene-butadiene block copolymer 70 to 30% by weight. It may be formed by the composition.

In the present invention, the intermediate layer 4 having a single layer structure is
In addition to the above structure, the density is 0.915 to 0.940.
g / cm ³ ethylene-α / olefin copolymer 30 to 7
0 parts by weight, 50 to 90% by weight of styrene and 5 parts of butadiene
It can be formed by a resin composition to which 0 to 10% by weight and 70 to 30 parts by weight of a styrene-butadiene block copolymer are added.

In this case, if the amount of styrene constituting the styrene-butadiene block copolymer used is less than 50% by weight, the tackiness of the film is increased and handling becomes difficult, and if it exceeds 90% by weight, it is difficult to handle at low temperature. Adhesion with the release layer deteriorates, which is not preferable. Then, the mixing ratio of the ethylene-α-olefin copolymer and the styrene-butadiene block copolymer in the mid layer 4 is such that the peel strength when peeling after the lid material 1 is heat-sealed to the polypropylene resin container, This greatly affects the transparency of the lid material 1. When the amount of the ethylene-α / olefin copolymer is less than 30% by weight and the amount of the styrene-butadiene block copolymer is more than 70% by weight, the film forming property of the intermediate layer 4 is lowered and the transparency of the lid material is also lowered. , The adhesion between the intermediate layer 4 and the release layer 5 is too large,
The peel strength of the lid material exceeds the suitable strength described below, which is not preferable. On the other hand, when the amount of the ethylene-α / olefin copolymer is more than 70% by weight and the amount of the styrene-butadiene block copolymer is less than 30% by weight, the adhesive force between the intermediate layer 4 and the peeling layer 5 is too small and the lid The peel strength of the material is lower than the appropriate strength, which is not preferable.

Further, in the present invention, the intermediate layer 4 having a single layer structure is prepared by using 30 to 70 parts by weight of an ethylene-α.olefin copolymer having a density of 0.915 to 0.940 g / cm ³ and 10 to 50 of styrene. Hydrogenated product of styrene-butadiene block copolymer of 7 wt% and 90-50 wt% of butadiene 7
It can be formed of a resin composition to which 0 to 30 parts by weight is added.

In this case, the density of the ethylene-α-olefin copolymer is less than 0.915 g / cm ³ , or 0.9
When it exceeds 40 g / cm ³ , the film forming property of the intermediate layer 4 due to the combination of the styrene-butadiene block copolymer with a hydrogenated product is deteriorated, which is not preferable. Further, when the amount of styrene constituting the hydrogenated product of the styrene-butadiene block copolymer used is less than 10% by weight, the tackiness of the film increases to cause blocking, which makes handling difficult, and exceeds 50% by weight. And the adhesion to the release layer at low temperature is poor, which is not preferable. By using a hydrogenated product, flexibility is imparted to the mid layer 4, and compatibility with the ethylene-α-olefin copolymer is good,
The transparency of the mid layer 4 is increased. Then, the mixing ratio of the ethylene-α-olefin copolymer and the hydrogenated product of the styrene-butadiene block copolymer in the mid layer 4 is such that when the lid material 1 is heat-sealed to the polypropylene resin container and then peeled off. The peel strength and the transparency of the lid material 1 are greatly affected. 30% by weight of ethylene-α / olefin copolymer
When the hydrogenated product of the styrene-butadiene block copolymer is more than 70% by weight, the film forming property of the intermediate layer 4 is lowered and the transparency of the lid material is also lowered, and the intermediate layer 4 and the peeling layer 5 are Is too large, and the peeling strength of the lid material exceeds the appropriate strength described below, which is not preferable. On the other hand, the ethylene-α / olefin copolymer amount exceeds 70% by weight, and the hydrogenated product of the styrene-butadiene block copolymer is 30%.
If it is less than wt%, the adhesion between the intermediate layer 4 and the peeling layer 5 is too small, and the peeling strength of the lid material is lower than the appropriate strength, which is not preferable.

Further, in the present invention, the intermediate layer 4 having a single layer structure can be formed of a linear saturated polyester resin having a glass transition temperature of 40 ° C. or higher.

Examples of the linear saturated polyester resin having a glass transition temperature of 40 ° C. or higher include alcohol components such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol, and adipic acid. , A dicarboxylic acid component of an aliphatic dicarboxylic acid such as sebacic acid or an aromatic dicarboxylic acid such as terephthalic acid, isophthalic acid or diphenylcarboxylic acid, specifically, ethylene glycol and terephthalic acid,
Ethylene glycol, isophthalic acid and terephthalic acid,
Co-condensation polymers such as 1,4-cyclohexanedimethanol, ethylene glycol and terephthalic acid, propylene glycol, isophthalic acid and terephthalic acid can be used. The glass transition temperature was set to 40 ° C. or higher in consideration of the environmental condition of using the lid material being lower than 40 ° C.

The thickness of the intermediate layer 4 having a single layer structure as described above is usually preferably about 10 to 60 μm. When the thickness of the intermediate layer is less than 10 μm, the film-forming property is poor, and when it exceeds 60 μm, the heat-sealing property of the lid material 1 is poor.

Further, in the lid member 1 of the present invention, the intermediate layer 4 can have a multi-layer structure.

FIG. 2 is a schematic cross-sectional view showing an example of the lid member of the present invention in which the intermediate layer has a two-layer structure. The intermediate layer 4 is composed of a first resin layer 4a and a second resin layer 4b. There is.

In this case, the first resin layer 4a has a density of 0.9.
It can be formed of 15 to 0.940 g / cm ³ of ethylene-α · olefin copolymer.

The second resin layer 4b has a density of 0.915.
To 0.940 g / cm ³ of ethylene-α / olefin copolymer 30 to 70% by weight, styrene 50 to 90% by weight and butadiene 50 to 10% by weight, styrene-butadiene block copolymer 70 to 30% by weight Resin composition with 10
Formed by a resin composition containing 5 to 30 parts by weight of a hydrogenated product of a styrene-butadiene block copolymer of 10 to 50% by weight of styrene and 90 to 50% by weight of butadiene, relative to 0 parts by weight. You can Further, the second resin layer 4b has a density of 0.915 to 0.940 g / cm ³
Ethylene-α / olefin copolymer of 30 to 70% by weight
And 50 to 90% by weight of styrene and 50 to 10 of butadiene
Styrene-butadiene block copolymer with 70% by weight
It is also possible to form the resin composition by adding 5 to 50 parts by weight of high-impact polystyrene to 100 parts by weight of the resin composition of 30 to 30% by weight. The second resin layer 4b has a density of 0.915 to 0.940 g / cm ³
Ethylene-α / olefin copolymer of 30 to 70% by weight
And 50 to 90% by weight of styrene and 50 to 10 of butadiene
Styrene-butadiene block copolymer with 70% by weight
10 to 50% by weight of styrene and 90 to 50% by weight of butadiene based on 100 parts by weight of the resin composition of 30 to 30% by weight.
5 to 30 parts by weight of a hydrogenated product of a styrene-butadiene block copolymer with
The resin composition may be formed by adding 50 parts by weight.

The thickness of each of the first resin layer 4a and the second resin layer 4b can be about 5 to 30 μm.

FIG. 3 is a schematic cross-sectional view showing an example of the lid material of the present invention in which the intermediate layer has a three-layer structure. The intermediate layer 4 includes a first resin layer 4a, a second resin layer 4b and a peeling layer 5. The third resin layer 4c is in contact with the third resin layer 4c.

In this case, the first resin layer 4a has a density of 0.9.
The second resin layer 4b is formed of an ethylene-α-olefin copolymer of 15 to 0.940 g / cm ³ and has a density of 0.
Styrene-butadiene block copolymer 70-30 wt% of 915-0.940 g / cm ³ ethylene-α / olefin copolymer 30-70 wt%, styrene 50-90 wt% and butadiene 50-10 wt%. % Resin composition.

The third resin layer 4c has a density of 0.91.
5 to 0.940 g / cm ³ of ethylene-α / olefin copolymer 30 to 70% by weight and styrene 50 to 90% by weight
Composition of styrene-butadiene block copolymer 70 to 30% by weight of styrene and 50 to 10% by weight of butadiene
It is formed by a resin composition in which 5 to 30 parts by weight of a hydrogenated product of a styrene-butadiene block copolymer of 10 to 50% by weight of styrene and 90 to 50% by weight of butadiene is added to 00 parts by weight. . In addition, the third resin layer 4
c is a styrene-butadiene block copolymer of 30 to 70% by weight of an ethylene-α-olefin copolymer having a density of 0.915 to 0.940 g / cm ³ , 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene. The resin composition may be formed by adding 5 to 50 parts by weight of high-impact polystyrene to 100 parts by weight of the resin composition containing 70 to 30% by weight of the polymer. Further, the third resin layer 4c contains 30 to 70% by weight of an ethylene-α-olefin copolymer having a density of 0.915 to 0.940 g / cm ³ , 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene. Of styrene-butadiene block copolymer of 70 to 30% by weight relative to 100 parts by weight of the resin composition,
Hydrogenated product of styrene-butadiene block copolymer of 0-50% by weight and butadiene 90-50% by weight 5-3
It can also be formed by a resin composition containing 0 parts by weight and 5 to 50 parts by weight of high-impact polystyrene.

The first resin layer 4a and the second resin layer 4
The thicknesses of b and the third resin layer 4c are 3 to 20 μm, respectively.
It can be set in the range of m.

The intermediate layer 4 as described above can be formed by a dry lamination method or an extrusion lamination method.

Since the lid 1 of the present invention includes the intermediate layer 4 as described above, when the lid 1 thermally fused to the polypropylene resin container is peeled off, the intermediate layer 4 and the peeling layer 5 are separated from each other. Delamination between layers (delamination), cohesive failure in the release layer 5, or delamination between the release layer 5 and the heat sealant layer 6 occur. The peel strength in this case is weaker than the adhesive strength between the peel layer 5 and the heat sealant layer 6 described later or the heat fusion strength between the heat sealant layer 6 and the polypropylene resin container.
It is preferably in the range of 0 to 1200 g / 15 mm. If the peel strength is less than 100 g / 15 mm, there is a risk that peeling may occur between the intermediate layer 4 and the peeling layer 5 when the container after heat-sealing the lid material is transferred, and the contents may fall off. . If the peel strength exceeds 1200 g / 15 mm, the polypropylene resin container may vibrate when the lid material is peeled off, and the contents may pop out, which is not preferable. The peel strength is 18 at 23 ° C. and 40% RH.
It is a value of 0 ° peeling (peeling speed = 300 mm / min). Also,
Peeling (interlayer peeling) between the intermediate layer 4 and the peeling layer 5 as described above occurs, or cohesive failure in the peeling layer 5 or the peeling layer 5 and the heat sealant layer 6
Whether or not the peeling between the layers and is caused can be appropriately selected by controlling the heat sealing conditions.
That is, by deteriorating the conditions at the time of heat sealing (heating temperature is high, heating time is long, and pressure is strong), delamination between the intermediate layer 4 and the peeling layer 5 can be caused. By loosening the condition (1), cohesive failure in the peeling layer 5 or peeling between the peeling layer 5 and the heat sealant layer 6 can be caused. As a specific example of the above heat sealing conditions, in the case of delamination, heating temperature = 130 to 180 ° C., heating time =
0.3 to 1.0 seconds, pressurization = about 1 to 5 kgf / cm ² , and in the case of cohesive failure, heating temperature = 100 to 150 ° C, heating time = 0.1 to 0.8 seconds, pressurization = 0.5 to 2 kgf / cm
It is about ² .

As described above, the lid member 1 should be sufficiently peeled from the polypropylene resin container after being heat-sealed by sufficiently increasing the heat-sealing strength of the heat sealant layer 6 to the synthetic resin container. You can

The release layer 5 of the lid 1 of the present invention is a thermoplastic resin made of at least one of polyester resin, polyurethane resin, vinyl chloride-vinyl acetate copolymer resin and acrylic resin, and fine particles as described later. It is formed by. As a combination of two or more thermoplastic resins, for example, a mixed resin of a polyurethane resin and a vinyl chloride-vinyl acetate copolymer resin (mixing ratio 9: 1 to 4:
6 is preferable), mixed resin of polyester resin and vinyl chloride-vinyl acetate copolymer resin (mixing ratio is preferably 1: 1 to 9.5: 0.5), acrylic resin and vinyl chloride- Examples thereof include a mixed resin with a vinyl acetate copolymer resin (mixing ratio is preferably in the range of 1: 1 to 9.5: 0.5). When the intermediate layer 4 is formed of a linear saturated polyester resin having a glass transition temperature of 40 ° C. or higher, it is preferable to use a mixed resin of polyurethane resin and vinyl chloride-vinyl acetate copolymer resin. .

Further, the release layer 5 includes fine metal particles of iron, silver, gold, nickel, aluminum, copper or the like, barium sulfate, calcium carbonate, silica, magnesium carbonate, aluminum hydroxide, magnesium hydroxide, silicates, At least one kind of fine particles containing an inorganic compound such as mica and potassium titanate as a main component is contained. Further, when imparting antistatic properties to the lid material 1 or adjusting the peel strength, conductive fine particles obtained by imparting conductivity to metal oxides such as tin oxide, zinc oxide and titanium oxide, barium sulfate, etc. Conductive fine particles that are made to have conductivity by an inorganic compound, carbon,
At least one of conductive fine particles obtained by imparting conductivity to sulfides such as zinc sulfide, copper sulfide, cadmium sulfide, nickel sulfide, and palladium sulfide, a Si-based organic compound, a surfactant, alumina, and silicon carbide is used as the release layer 5 Can be included. The primary particles of such fine particles and conductive fine particles preferably have an average particle diameter of about 0.01 to 30 μm. In this case, the mixing ratio of the thermoplastic resin and the fine particles, conductive fine particles, etc. in the release layer 5 is 10: 1 to 1: 1.
It is preferably in the range of 0. When the mixing ratio of the fine particles, the conductive fine particles, etc. is less than the above range, the adhesion between the intermediate layer 4 and the peeling layer 5 becomes weak and the peel strength becomes low. Antistatic effect cannot be obtained. On the other hand, when it exceeds the above range, the transparency of the lid material 1 becomes too poor, which is not preferable.

The thickness of the release layer 5 is 0.1 to 10 μm,
Particularly, the range of 1 to 5 μm is preferable.

When imparting antistatic properties to such a release layer 5, the surface resistivity thereof is in the range of 10 ⁵ to 10 ¹² Ω at 22 ° C. and 40% RH, and 23 ± 5.
5000V to 99% under 12 ° C and 12 ± 3% RH
By setting the charge decay time required to decay to 2 seconds or less, the peeling layer 5 has excellent electrostatic characteristics. When the above surface low efficiency is more than 10 ¹² Omega, peeling effect is extremely poor, the electronic component becomes difficult to protect from electrostatic breakdown, and if less than 10 ⁵ Omega, through the cover member from the outside There is a risk that electricity will be applied to the electronic components, and there is a risk that the electronic components will be electrically destroyed. On the other hand, if the charge decay time, which is a measure of the diffusion rate of charges generated by static electricity, exceeds 2 seconds, the peeling effect becomes extremely poor, and it becomes difficult to protect electronic components from electrostatic breakdown. The above surface resistivity and charge decay time are
It can be measured according to MIL-B-81705C which is a US military standard.

The release layer 5 may contain additives such as a dispersion stabilizer and an antiblocking agent, if necessary.

The release layer 5 as described above can be formed by coating on the intermediate layer 4 by using a known coating means.

Heat sealant layer 6 of lid 1 of the present invention
Is formed of a thermoplastic resin whose main component is ethylene-vinyl acetate resin. The content rate of the ethylene-vinyl acetate resin in the heat sealant layer 6 is 20.
To 100% by weight, preferably 60 to 100% by weight. When the content of the ethylene-vinyl acetate resin is less than 20% by weight, the adhesion strength to the polypropylene resin container becomes low, and the peeling occurs at the interface between the lid material 1 and the polypropylene resin container when the lid material 1 is peeled off. (Interfacial peeling) occurs, the peeling strength changes during storage, and the fluctuation range of the peeling strength depending on the sealing condition is large, which is not preferable.

Examples of the thermoplastic resin other than the ethylene-vinyl acetate resin contained in the heat sealant layer 6 include urethane resin, acrylic resin, vinyl chloride-vinyl acetate copolymer, polyester resin and the like.

The thickness of the heat sealant layer 6 is 0.1 to 1
0 μm, particularly 0.3 to 2 μm is preferable. When the thickness of the heat sealant layer 6 is less than 0.1 μm, it is difficult to form the heat sealant layer, the haze value is 50% or more, and sufficient transparency cannot be obtained. Is more than 10 μm, the total light transmittance becomes 75% or less, which is also not preferable because the transparency is lowered. Even if the heat sealant layer 6 is laminated on the release layer 5, the surface resistivity of the release layer 5 is within the above range (10 ⁵
10 If ¹² Omega) in a heat surface resistivity of the sealant layer 6 is 22 ° C., 10 ⁵ to 10 under 40% RH ¹²
Within the range of Ω, 23 ± 5 ℃, 12 ± 3% RH
Below, the charge decay time required to decay from 5000 V to 99% is also 2 seconds or less, and the lid 1 has excellent antistatic properties.

The heat sealant layer 6 described above is formed on the entire surface of one side of the lid member 1. In the lid member of the present invention, the heat sealant layer 6 is formed on one side of the lid member 1 in a sea-island shape. It may be formed in a pattern. in this case,
The area of one sea-island pattern is 0.01-0.5 mm ^2.
Is preferred. The area of one sea-island pattern is 0.
If it is less than 01 mm ² , the distance between the sea-island patterns becomes large, the container may flutter during peeling, and there is a risk of the contents popping out, which is not preferable. On the other hand, 0.5m
When it exceeds m ² , transparency is deteriorated due to diffuse reflection of light between the sea-island pattern and grooves formed between the sea-island patterns, which is not preferable. Further, the total area of the sea-island-like heat sealant layer 6 provided on one surface of the lid material 1 is preferably within a range of 60 to 98% of one area of the lid material.

The above-mentioned sea-island pattern is not particularly limited, but for example, a circular pattern shape as shown in FIG.
It is possible to have a square pattern shape as shown in FIG. Further, the heat sealant layer 6 having the above-described sea-island pattern may be formed in a region slightly larger than a region corresponding to the line-shaped heat-melted portion H as described later.

As described above, by forming the heat sealant layer 6 on one surface of the lid member 1 in a sea-island pattern,
The heat sealant layer material can be reduced, and the manufacturing cost of the lid material can be kept low. Further, as described above, since the peeling layer 5 contains the conductive fine particles and the like in the predetermined resin, the peeling layer 5 is exposed a lot by forming the heat sealant layer in a sea-island pattern, and the peeling layer 5 The heat fusion property can be utilized. That is, the heat sealing temperature can be lowered while maintaining good peeling characteristics, and the demand for energy saving can be met.

The lid 1 of the present invention is peeled between the intermediate layer 4 and the peeling layer 5, or is cohesively broken in the peeling layer 5 or peeled between the peeling layer 5 and the heat sealant layer 6. Therefore, stable peeling performance is obtained without being affected by the heat-sealing conditions for the polypropylene resin container. Such delamination or peeling due to cohesive failure will be described with reference to FIGS. 6 to 9. First, as shown in FIGS. 6 and 7, for example, a carrier tape 11 having an embossed portion 12 is attached to a lid member 1 as shown in FIG.
Are heat-sealed. This heat fusion is performed on both ends of the embossed portion 12 in a line shape with a predetermined width. In the illustrated example, the line-shaped heat-sealing portion H is shown by a shaded portion. In this state, the adhesion strength between the intermediate layer 4 and the peeling layer 5 of the lid material 1 is 100.
It is in the range of up to 1200 g / 15 mm, which is smaller than the adhesive strength between the release layer 5 and the heat sealant layer 6 or the heat fusion strength between the heat sealant layer 6 and the carrier tape 11. Next, when the lid material 1 is peeled off from the carrier tape 11, the peeling layer 5 and the heat sealant layer 6 in the line-shaped heat-sealed portion H are separated from the carrier tape 1.
1 is still heat-sealed, and peeling occurs between the intermediate layer 4 and the peeling layer 5 (FIG. 8). Therefore, the lid member 1 is peeled off with the line-shaped heat-sealed portion H of the peeling layer 5 and the heat sealant layer 6 left on the carrier tape. Alternatively, in the line-shaped heat-sealing portion H, cohesive failure occurs in the peeling layer 5, and a part of the peeling layer 5 and the heat sealant layer 6 are heat-sealed to the carrier tape 11 and the lid material 1 is It is peeled off (FIG. 9). That is, the lid member 1 of the present invention has the contradictory characteristics of high heat fusion property to the carrier tape 11 and easy peeling property at the time of peeling.

The lid member of the present invention may have an antireflection film or an antireflection film and an antistatic layer on the biaxially stretched resin layer, in addition to the above-described embodiments. 10 and 11 are schematic cross-sectional views showing other examples of such a lid member of the present invention. In FIG. 10, the lid member 21 includes a biaxially stretched resin layer 22, and an intermediate layer 24 sequentially laminated on one surface of the biaxially stretched resin layer 22 with an adhesive layer 23 interposed therebetween.
The peeling layer 25 and the heat sealant layer 26 are provided, and the antireflection film 27 is provided on the other surface of the biaxially stretched resin layer 22. Further, in FIG. 11, the biaxially stretched resin layer 2 is further added.
An antistatic layer 28 is provided between the film 2 and the antireflection film 27.

The antireflection film 27 is intended to suppress diffused reflection in the lid member or the reflection of light from the light source, and to make it easier to visually check the inside of the container. Such an antireflection film 27 is formed of calcium fluoride, sodium fluoride, lithium fluoride, magnesium fluoride, lanthanum fluoride,
Neodymium fluoride, cerium fluoride, silicon dioxide, aluminum oxide, magnesium monoxide, thorium oxide, lanthanum oxide, silicon monoxide, yttrium oxide, zirconium oxide, titanium oxide, cerium oxide, zinc oxide, bismuth oxide, cadmium sulfide, etc. One kind or two or more kinds can be formed by using an ink dispersed in a thermoplastic resin or can be directly formed into a film. As the thermoplastic resin, polyester type, polyurethane type, acrylic type, vinyl chloride-
Vinyl acetate copolymer type, polyvinyl acetate type, phenol type, xylene type, urea resin type and melanin type, ketone type, coumarone / indene type, petroleum resin type, terpene type,
Cyclized rubber type, chlorinated rubber type, alkyd type, polyamide type,
Examples thereof include polyvinyl alcohol type, polyvinyl butyral type, chlorinated polypropylene type, styrene type, epoxy type and cellulose derivatives. As a method for forming the antireflection film 27 by applying ink, an air doctor coating method, a blade coating method, a knife coating method, a rod coating method, a roll coating method, a gravure coating method, a screen method, a kiss coating method, a bead coating method, a slot orifice. The coating method, the spray method, etc. can be mentioned.
When directly forming a film, a vacuum vapor deposition method, a sputtering method, or the like can be used. Such an antireflection film 27
May have either a single-layer structure or a multi-layer structure, and the film thickness is preferably about 0.01 to 0.5 μm.

The antistatic layer 28 is formed for the purpose of preventing dust from adhering to the surface of the lid member 21 due to static electricity. This antistatic layer 28
Is an anionic, cationic, nonionic or amphoteric surfactant as an antistatic agent, a fatty acid derivative,
At least one of tetrafunctional silicon partial hydrolyzate, conductive fine powder obtained by subjecting metal fine powder, metal oxide, metal sulfide or sulfate to conductive treatment, and conductive carbon It is a layer.

As the above-mentioned anionic surfactant, sulfated oil, soap, sulfated ester oil, sulfated amide oil, sulfate ester salts of olefin, fatty alcohol sulfate ester salt, alkyl sulfate ester salt, fatty acid ethyl sulfonic acid. Examples thereof include salts, alkyl sulfonates, alkyl benzene sulfonates, mixtures of naphthalene sulfonic acid and formalin, succinic acid ester sulfonic acid salts, and phosphoric acid ester salts.

Examples of cationic surfactants include primary amine salts, tertiary amine salts, quaternary ammonium compounds, pyridine derivatives and the like.

As the nonionic surfactant, a partial fatty acid ester of polyhydric alcohol, ethylene oxide adduct of fatty alcohol, ethylene oxide adduct of fatty acid, ethylene oxide adduct of fatty amino or fatty acid amide, alkylphenol. And ethylene oxide adduct of alkyl naphthol, ethylene oxide adduct of partial fatty acid ester of polyhydric alcohol, and the like.

Further, examples of the amphoteric surfactant include a carboxylic acid derivative and an imidazoline derivative.

The antistatic layer 28 can be formed on the biaxially stretched resin layer 22 by using the above antistatic agent alone. Alternatively, it may be formed by applying an ink in which an antistatic agent is dispersed to a thermoplastic resin that can be used in forming the antireflection film 27. The thickness of such an antistatic layer 28 is preferably about 0.2 to 20 μm.

The antistatic layer 28 has a surface resistivity in the range of 10 ⁵ to 10 ¹² Ω at 22 ° C. and 40% RH, and at 23 ± 5 ° C. and 12 ± 3% RH. The charge decay time required to decay from 5000 V to 99% is 2 seconds or less, and has an excellent antistatic effect.

In the lid member 21, the biaxially stretched resin layer 22, the adhesive layer 23, the intermediate layer 24, the peeling layer 25 and the heat sealant layer 26 are the same as the corresponding layers constituting the lid member 1. Therefore, the description is omitted.

Next, the lid material of the present invention will be described in more detail with reference to specific examples. (Example 1-A) As a biaxially stretched resin layer, a biaxially stretched polyethylene terephthalate (PET) film (Spett 6140, manufactured by Toyobo Co., Ltd., thickness 12 μm, corona treated product) was prepared. A polyethyleneimine solution (P-100 manufactured by Nippon Shokubai Kagaku Co., Ltd.) was prepared as an adhesive. Furthermore, as an adhesive layer, low density polyethylene (LDPE) (Mitsui Petrochemical Co., Ltd. Mirason 16-
P) was prepared.

Next, in order to form an intermediate layer, the following linear low density polyethylene (L.LDPE) as an ethylene-.alpha..olefin copolymer and styrene 70-90 are used.
The following S / B copolymer as a styrene-butadiene block copolymer (S / B copolymer) of 20% by weight and 30 to 10% by weight of butadiene, 20 to 50% by weight of styrene and 80 to 50% by weight of butadiene. The following S.B copolymer hydrogenated products and high-impact polystyrene (HIPS) were prepared as hydrogenated products of the styrene-butadiene block copolymer (S.B copolymer). Further, the following S / B block elastomer was prepared as a non-hydrogenated product of a styrene-butadiene block copolymer (S / B copolymer) of 20 to 50% by weight of styrene and 80 to 50% by weight of butadiene.

L·LDPE: Mult Petroleum Chemical Co., Ltd. Ultzex 3550A Density = 0.925 g / cm ³ S / B Copolymer: Asaflex 810 S / B Copolymer Hydrogenation Thing: Asahi Kasei Kogyo Co., Ltd. Tuftec H1041 HIPS: Asahi Kasei Kogyo Co., Ltd. Styron 475D S / B block elastomer: Asahi Kasei Kogyo Co., Ltd. Toughprene A Next, using such materials, first, PET film After applying the adhesive to the above, an intermediate layer (single-layer structure, thickness 30 μm) was formed by an extrusion lamination method via an LDPE layer (thickness 20 μm) under the mixing conditions shown in Table 1 below. Then, a release layer coating solution having the following composition was applied onto the intermediate layer by a gravure reverse method to form a release layer (thickness 2
μm), a coating solution for heat sealant layer having the following composition is applied by a gravure reverse method to form a heat sealant layer (thickness 0.5 μm), and a lid material (Sample 1).
-11 and comparative samples 1-5) were prepared. (Composition of coating liquid for release layer) Polyurethane resin (Nipporan 5120 manufactured by Nippon Polyurethane Industry Co., Ltd.) 30 parts by weight Vinyl chloride-vinyl acetate copolymer resin (Vinylite VAGH manufactured by Union Carbide Co., Ltd.) 7.5 weight Part Fine powder (conductive fine particles T-1 manufactured by Mitsubishi Materials Corp.) 62.5 parts by weight (composition of coating liquid for heat sealant layer) Ethylene-vinyl acetate resin (Q066PP manufactured by Toyo Ink Mfg. Co., Ltd.) 100 Parts by weight

[0068]

[Table 1] Further, using each of the above materials, first, an adhesive is applied to the PET film, and then the L·LDPE layer is formed through the LDPE layer (thickness 20 μm) by the extrusion lamination method.
An intermediate layer (two-layer structure, thickness 30 μm) as shown in FIG. 2 is formed by forming a first layer (thickness 15 μm) consisting of layers and a second layer (thickness 15 μm) having the composition shown in Table 2 below. ) Was formed. After that, the release layer coating solution and the heat sealant layer coating solution having the above-mentioned composition are applied on the intermediate layer by a gravure reverse method to form a release layer (thickness 2 μm) and a heat sealant layer (thickness 0.5 μm). To form the lid material (Sample 1
2 to 17 and comparative samples 6 to 8) were prepared.

[0069]

[Table 2] Further, using each of the above materials, first, an adhesive is applied to the PET film, and then the L·LDP is formed through the LDPE layer (thickness 20 μm) by the extrusion lamination method.
As shown in FIG. 3, a first layer (thickness 10 μm) consisting of an E layer, a second layer (thickness 10 μm) and a third layer (thickness 10 μm) having the compositions shown in Table 3 below are formed. An intermediate layer (three-layer structure, thickness 30 μm) was formed. After that, the release layer coating solution and the heat sealant layer coating solution having the above-mentioned compositions are applied on the intermediate layer by a gravure reverse method to form a release layer (thickness 2 μm) and a heat sealant layer (thickness 0.5).
μm) to form a lid material (samples 18 to 25, comparative sample 9)
.About.12) was prepared.

[0070]

[Table 3] Furthermore, except that the heat sealant layer was not formed, Sample 2
(Intermediate layer is a single layer), Sample 15 (intermediate layer is two layers) and Sample 25 (intermediate layer is three layers) in the same manner as the lid material (Comparative Sample 1).
3-15) was prepared.

Next, the haze and the total light transmittance of each of the above-mentioned lid materials (Samples 1 to 25 and Comparative Samples 1 to 15) were measured under the following conditions. In addition, each of the above lid materials was applied to a polypropylene resin base material (chip sheet manufactured by Showa Denko KK) using a heat seal bar at 150 ° C., 0.5 seconds, 3.0.
After heat-sealing under the condition of kgf / cm ² , the peel strength was measured under the following conditions. (Measurement conditions of haze degree and total light transmittance) Suga Test Instruments Co., Ltd. color computer SM-5SC was used for measurement. (Peeling strength measurement conditions) Tensilon universal tester manufactured by Toyo Baldwin Co., Ltd. at 23 ° C. and 40% RH
It was measured with HTH-100. (Peeling speed = 300 mm / min, 1
80 ° peeling) The measurement results and peeling form of the above items for each lid material are shown in Table 4 below.

[0072]

[Table 4] (Example 1-B) A heat sealant layer coating solution was applied by a gravure method to form a heat sealant layer (thickness 0.5 μm).
m, sea-island pattern (pattern shape = square, one pattern area = 0.04 mm ² ) except that the lid material (Samples 1 to 25, Comparative sample 1) was prepared in the same manner as in Example 1-A. ~
15) was created. Using this lid material, a polypropylene resin substrate (manufactured by Showa Denko KK) in the same manner as in Example 1-A
Each lid material is heat-sealed to the chip sheet), and then the first embodiment is performed.
The peel strength was measured in the same manner as in -A.

The measurement results and the peeling form of each lid material were the same as those in Example 1-A, and thus the description thereof is omitted. (Example 1-C) Lids (Samples 1 to 25 and Comparative samples 1 to 15) were prepared in the same manner as in Example 1-B. Using this lid material, heat fusion conditions were 140 ° C, 0.4 seconds, 1.0 kgf /
Each cover material was heat-sealed to a polypropylene resin base material (chip sheet manufactured by Showa Denko KK) in the same manner as in Example 1-A except for cm ^2, and then peeled off in the same manner as in Example 1-A. The strength was measured.

The measurement results and peeling morphology of each lid material are shown in Table 5 below.

[0075]

[Table 5] (Example 1-D) Lids (Samples 1 to 25 and Comparative samples 1 to 15) were prepared in the same manner as in Example 1-A. Using this lid material,
Each polypropylene resin base material (chip sheet manufactured by Showa Denko KK) was capped in the same manner as in Example 1-A except that the heat fusion conditions were 140 ° C., 0.4 seconds, and 1.0 kgf / cm ^2. The material was heat-sealed, and then the peel strength was measured as in Example 1-A.

The measurement results and the peeling form of each lid material are shown in Table 6 below.

[0077]

[Table 6] (Example 2-A) As a biaxially stretched resin layer, a biaxially stretched polyethylene terephthalate (PET) film (Spett 6140, manufactured by Toyobo Co., Ltd., thickness 12 μm, corona treated product) was prepared.

Next, in order to form an intermediate layer, the following linear low-density polyethylene (L.LDPE) as an ethylene-.alpha..olefin copolymer and styrene 50-90 are used.
The following S.B copolymer was prepared as a styrene-butadiene block copolymer (S.B copolymer) containing 50% by weight of butadiene and 50 to 10% by weight of butadiene, and a film was obtained by an inflation method.

L / LDPE: Mitsui Petrochemical Industry Co., Ltd.
Ultzex 3550A manufactured by Density = 0.925 g / cm ³ S / B copolymer: Asaflex 8 manufactured by Asahi Kasei Corporation
10 In addition, in order to form the release layer, the following polyester resin, vinyl chloride-vinyl acetate copolymer resin, polyurethane resin and fine powder were prepared.

Polyester resin: manufactured by Toyobo Co., Ltd. Byron (glass transition temperature = 50 ° C.) Vinyl chloride-vinyl acetate copolymer resin: manufactured by Union Carbide Vinylite VAGH Polyurethane resin: manufactured by Nippon Polyurethane Industry Co., Ltd. Nipporan 5120 Micro Powder: Mitsui Mining & Smelting Co., Ltd. Pastran IV (average particle size = 0.1 μm) Further, in order to form a heat sealant layer, ethylene-vinyl acetate resin (Toyo Ink Mfg. Co., Ltd. Q
066PP) was prepared. Next, using each of the above materials, first, an adhesive is applied to the PET film, and then the LDPE layer (thickness 20 μm is formed by the extrusion lamination method.
L) LDPE shown in Tables 7 and 8 below via m)
Intermediate layer (thickness 30 μm) under the mixing condition of S and B copolymer
Was formed. After that, a release layer (thickness: 2 μm) having the composition shown in Tables 7 and 8 below was formed on the intermediate layer by a gravure reverse method, and then a heat sealant layer (thickness: 0.5 μm) by a gravure reverse method. To form the lid material (Sample 1
26) were prepared.

Furthermore, a lid member (Sample 27, Sample 27, Sample 15) was prepared in the same manner as Sample 4 and Sample 15 except that the heat sealant layer was not formed.
28) was prepared.

[0082]

[Table 7]

[0083]

[Table 8] Next, the haze degree, the total light transmittance, and the peel strength of each of the above lid materials (Samples 1 to 28) were measured in the same manner as in Example 1-A. In addition, blocking resistance was measured under the following conditions. (Blocking resistance) A lid material having a length of 100 m and a width of 50 mm was wound into a reel and allowed to stand in an environment of 40 ° C. and 90% RH for 24 hours, and the occurrence of blocking was observed.

The measurement results of the above items and the peeling form of each lid material are shown in Tables 9 and 10 below.

[0085]

[Table 9]

[0086]

[Table 10] As shown in Table 9 and Table 10, Samples 1 to 6 and Samples 15 to 20 had good transparency, and peeling occurred between the intermediate layer and the peeling layer with an appropriate peeling strength. On the other hand, in Samples 7, 9, and 12, the total light transmittance was less than 75% and the transparency was poor because the content of fine powder was large. Further, since the samples 8, 10, and 22 contained a small amount of fine powder, the peel strength was less than the appropriate strength. Further, Samples 11, 12, and 24 had poor coatability because the release layer had a large amount of vinyl chloride-vinyl acetate copolymer resin. Also,
Since the sample 23 had a large amount of polyurethane resin, the peel strength was less than the proper strength. Samples 13 and 25 had a slightly large amount of L·LDPE in the intermediate layer, and conversely, Samples 14 and 26 had L·LDPE.
Due to the small amount of LDPE, the peel strength of Samples 13 and 25 was low, and the peel strength of Samples 14 and 26 was too high. Further, since Samples 27 and 28 did not have the heat sealant layer, they had a high haze value and did not have sufficient transparency. (Example 2-B) A heat sealant layer coating solution was applied by a gravure method to form a heat sealant layer (thickness 0.5 μm).
m, a sea-island pattern (pattern shape = square, one pattern area = 0.04 mm ² ) was formed, and lid materials (samples 1 to 28) were prepared in the same manner as in Example 2-A. .
The haze, total light transmittance, blocking resistance and peel strength of this lid material were measured in the same manner as in Example 2-A.

The measurement results and the peeling form of each lid material were the same as in Example 2-A, and thus the description thereof is omitted. (Example 2-C) Lids (Samples 1 to 28) were prepared in the same manner as in Example 2-A. About this lid material, Example 2-
The haze degree, total light transmittance, blocking resistance, and peel strength were measured in the same manner as in A. The heat fusion condition is 14
The temperature was 0 ° C., 0.4 second, and 1.0 kgf / cm ² .

The measurement results and peeling morphology of each lid material are shown in Tables 11 and 12 below.

[0089]

[Table 11]

[0090]

[Table 12] (Example 3-A) As a biaxially stretched resin layer, a biaxially stretched polyethylene terephthalate (PET) film (Spett 6140, manufactured by Toyobo Co., Ltd., thickness 12 μm, corona treated product) was prepared. A polyethyleneimine solution (P-100 manufactured by Nippon Shokubai Kagaku Co., Ltd.) was prepared as an adhesive. Furthermore, as an adhesive layer, low density polyethylene (LDPE) (Mitsui Petrochemical Co., Ltd. Mirason 16-
P) was prepared.

Next, in order to form an intermediate layer, the following linear low-density polyethylene (L.LDPE) as an ethylene-.alpha..olefin copolymer and styrene 10 to 50 are used.
As a hydrogenated product of a styrene-butadiene block copolymer (S / B copolymer) containing 90% by weight of styrene and 90 to 50% by weight of butadiene, the following hydrogenated product of the S / B copolymer is prepared,
A film was obtained by the inflation method.

L / LDPE: Mitsui Petrochemical Industry Co., Ltd.
Ultzex 3550A manufactured by Density = 0.925g / cm ³ S / B copolymer Hydrogenated product: Tuftec H1041 manufactured by Asahi Kasei Kogyo Co., Ltd. Further, in order to form a release layer, the following polyester resin, vinyl chloride-vinyl acetate is used. A copolymer resin, a polyurethane resin, and a fine powder were prepared.

Polyester resin: manufactured by Toyobo Co., Ltd. Byron (glass transition temperature = 50 ° C.) Vinyl chloride-vinyl acetate copolymer resin: manufactured by Union Carbide Vinylite VAGH Polyurethane resin: manufactured by Nippon Polyurethane Industry Co., Ltd. Nipporan 5120 Micro Powder: Mitsui Mining & Smelting Co., Ltd. Pastran IV (average particle size = 0.1 μm) Further, in order to form a heat sealant layer, ethylene-vinyl acetate resin (Toyo Ink Mfg. Co., Ltd. Q
066PP) was prepared. Next, using each of the above materials, first, an adhesive is applied to the PET film, and then the LDPE layer (thickness 20 μm is formed by the extrusion lamination method.
L) LD shown in Tables 13 and 14 below via m)
An intermediate layer (thickness 30 μm) was formed under the mixed conditions of PE and S / B copolymer hydrogenated product. Then, a release layer (having a thickness of 2 μm) having the composition shown in Tables 13 and 14 below was formed on the intermediate layer.
m) was formed by the gravure reverse method, and then a heat sealant layer (thickness: 0.5 μm) was formed by the gravure method to prepare lid materials (Samples 1 to 26).

Further, a lid member (Sample 27, Sample 27, Sample 15) was prepared in the same manner as Sample 4 and Sample 15 except that the heat sealant layer was not formed.
28) was prepared.

[0095]

[Table 13]

[0096]

[Table 14] Next, the haze degree, total light transmittance, peeling strength, and blocking resistance of each of the above lid materials (Samples 1 to 28) were measured in the same manner as in Example 1-A and Example 2-A.

Tables 15 and 16 below show the measurement results and the peeling form of the above items for each lid member.

[0098]

[Table 15]

[0099]

[Table 16] As shown in Table 15 and Table 16, each lid member of Example 3 (Samples 1 to 28) is the same as each lid member of Example 2-A (Sample 1).
The same tendency as that observed in Samples 1 to 28)
6, Samples 15 to 20 had good transparency, and peeling occurred between the intermediate layer and the peeling layer with an appropriate peeling strength. On the other hand, Samples 7, 9, and 12 contain a large amount of fine powder,
The total light transmittance was below 75%, and the transparency was poor.
Further, since the samples 8, 10, and 22 contained a small amount of fine powder, the peel strength was less than the appropriate strength. Further, Samples 11, 12, and 24 had poor coatability because the release layer had a large amount of vinyl chloride-vinyl acetate copolymer resin. Further, since the sample 23 has a large amount of polyurethane resin,
The peel strength was less than the proper strength. Samples 13 and 25
Shows that the amount of L / LDPE in the intermediate layer is rather large, and conversely, sample 1
Since Nos. 4 and 26 had a small amount of L·LDPE, Samples 13 and 25 had low peel strength, and Samples 14 and 26 had too high peel strength. Furthermore, the samples 27 and 28 are
Since there was no heat sealant layer, it had a high haze value and did not have sufficient transparency. (Example 3-B) A heat sealant layer coating solution was applied by a gravure method to form a heat sealant layer (thickness 0.5 μm).
m, a sea-island pattern (pattern shape = square, one pattern area = 0.04 mm ² ) was formed, and lid materials (samples 1 to 28) were prepared in the same manner as in Example 3-A. .
The haze, total light transmittance, blocking resistance, and peel strength of this lid material were measured in the same manner as in Example 3-A.

The measurement results and the peeling form of each lid material were the same as those in Example 3-A, and thus the description thereof is omitted. (Example 3-C) Lid materials (Samples 1 to 28) were prepared in the same manner as in Example 3-A. About this lid material, Example 3-
The haze degree, total light transmittance, blocking resistance, and peel strength were measured in the same manner as in A. The heat fusion condition is 14
The temperature was 0 ° C., 0.4 second, and 1.0 kgf / cm ² .

The measurement results and peeling morphology of each lid material are shown in Tables 17 and 18 below.

[0102]

[Table 17]

[0103]

[Table 18] (Example 4-A) As a biaxially stretched resin layer, a biaxially stretched polyethylene terephthalate (PET) film (Spett 6140 manufactured by Toyobo Co., Ltd., thickness 12 μm, corona treated product) was prepared. A polyethyleneimine solution (P-100 manufactured by Nippon Shokubai Kagaku Co., Ltd.) was prepared as an adhesive. Furthermore, as an adhesive layer, low density polyethylene (LDPE) (Mitsui Petrochemical Co., Ltd. Mirason 16-
P) was prepared.

Next, in order to form an intermediate layer, a saturated polyester resin film (KS-0 manufactured by Tohcello Chemical Co., Ltd.)
11C, thickness 30 μm, glass transition temperature 50 ° C.) was prepared.

In order to form the release layer, the following polyurethane resin, vinyl chloride-vinyl acetate copolymer resin and fine powder were prepared.

Polyurethane resin: Nippon Polyurethane Industry Co., Ltd., Nipporan 5120 Vinyl chloride-vinyl acetate copolymer resin: Union Carbide, Vinylite VAGH Fine powder: Fuji Devison Chemical Co., Ltd. Syloid 16
2 (silica) (average particle size = 0.1 μm) Further, in order to form a heat sealant layer, ethylene-vinyl acetate resin (Q manufactured by Toyo Ink Mfg. Co., Ltd.)
066PP) was prepared. Next, using each of the above materials, first, an adhesive is applied to the PET film, and then the LDPE layer (thickness 20 μm is formed by the extrusion lamination method.
m), an intermediate layer (thickness 30 μm) made of a saturated polyester resin film was formed. Then, a release layer (thickness: 2 μm) having the composition shown in Table 19 below was formed on the intermediate layer by a gravure reverse method, and then a heat sealant layer (thickness: 0.5 μm) was formed by a gravure reverse method. Then, lid materials (Samples 1 to 10) were prepared.

[0107]

[Table 19] Next, with respect to each of the above-mentioned lid materials (Samples 1 to 10), the haze degree, total light transmittance and peel strength were measured in the same manner as in Example 1-A.

The measurement results of the above items and the peeling form of each lid material are shown in Table 20 below.

[0109]

[Table 20] (Example 4-B) A heat sealant layer coating solution was applied by a gravure method to form a heat sealant layer (thickness 0.5 μm).
m, a sea-island pattern (pattern shape = square, one pattern area = 0.04 mm ² ) was formed, and lid materials (samples 1 to 10) were prepared in the same manner as in Example 4-A. .
The haze, the total light transmittance, and the peel strength of this lid material were measured in the same manner as in Example 4-A.

Since the measurement results and the peeling form of each lid material were the same as those in Example 4-A, the description thereof is omitted. (Example 4-C) Lids (Samples 1 to 10) were prepared in the same manner as in Example 4-A. About this lid material, Example 4-
In the same manner as in A, the haze degree, total light transmittance and peel strength were measured. The heat fusion conditions are 140 ° C., 0.4 seconds,
It was set to 1.0 kgf / cm ² .

The measurement results and peeling morphology of each lid material are shown in Table 21 below.

[0112]

[Table 21] (Example 5) As a biaxially stretched resin layer, a biaxially stretched polyester film (Tetoron Tetron Co., Ltd., thickness 16 μm)
An intermediate layer, a release layer and a heat sealant layer were formed on one surface of the biaxially stretched polyester film in the same manner as in Sample 15 of Example 2-A except that m) was used.

Next, the following two types of antistatic agents were prepared as antistatic agents.

Nippon Oil & Fats Co., Ltd. New Elegan A (cationic) ... A Catalytic Chemicals Co., Ltd. ELCOM P3501 ... B Furthermore, as an antireflection film, an antireflection coating composition having the following composition Prepared. (Composition of coating for antireflection film) Magnesium fluoride 30 parts by weight Polyester resin (Vylon manufactured by Toyobo Co., Ltd.) (Glass transition temperature 50 ° C) 20 parts by weight Solvent (toluene / methyl ethyl ketone = 1/1) 50 By weight, an antistatic agent is applied to the surface of the biaxially stretched polyester film opposite to the surface on which the intermediate layer, the release layer and the heat sealant layer are formed by the gravure reverse method to form an antistatic layer (thickness 0.5 μm). Then, a coating material for an antireflection film is applied on the antistatic layer by a gravure reverse method to form an antireflection film (thickness 0.1 μm) to prepare a lid material (samples 1 to 2). did.

Next, for each of the above-mentioned lid materials (Samples 1 and 2), the haze degree, total light transmittance, surface resistivity and charge decay time were measured in the same manner as in Example 1-A and Example 2-A. It was measured.

Table 22 below shows the measurement results of the above items and the presence or absence of surface reflection for each lid member.

[0117]

[Table 22] As shown in Table 22, Samples 1 to 1 each provided with an antireflection layer
In No. 2, there was no surface reflection, and it was possible to effectively prevent irregular reflection in the lid material and shadowing of the light source.

[0118]

As described in detail above, according to the present invention, the release layer is located between the biaxially stretched resin layer and the heat sealant layer, adjacent to the heat sealant layer constituting the lid material. The intermediate layer is located between the biaxially stretched resin layer and the peeling layer, and the heat sealant layer is mainly composed of ethylene-vinyl acetate, so that the lid material is good for polypropylene resin containers. When the lid material is peeled off, peeling between the intermediate layer and the peeling layer occurs, or cohesive failure inside the peeling layer or peeling between the peeling layer and the heat sealant layer occurs. As a result, good peelability can be obtained while maintaining high adhesiveness of the heat sealant layer, and it becomes easy to set conditions for heat-sealing the lid member to the polypropylene resin container.
Furthermore, by forming the heat sealant layer in a sea-island pattern, it is possible to reduce the raw material for the heat sealant layer and reduce the manufacturing cost.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a lid member of the present invention.

FIG. 2 is a schematic cross-sectional view showing another example of the lid material of the present invention.

FIG. 3 is a schematic cross-sectional view showing another example of the lid material of the present invention.

FIG. 4 is a diagram showing an example of a pattern shape of a heat sealant layer of the lid material of the present invention.

FIG. 5 is a diagram showing another example of the pattern shape of the heat sealant layer of the lid material of the present invention.

FIG. 6 is a perspective view showing a state in which the lid member of the present invention is heat-sealed on a carrier tape.

7 is a sectional view taken along line VII-VII of FIG.

FIG. 8 is a view corresponding to FIG. 7, showing a state in which the lid member is peeled off from the carrier tape.

FIG. 9 is a view corresponding to FIG. 7, showing a state in which the lid member is peeled off from the carrier tape.

FIG. 10 is a schematic cross-sectional view showing another example of the lid material of the present invention.

FIG. 11 is a schematic cross-sectional view showing another example of the lid material of the present invention.

[Explanation of symbols]

 1, 21 ... Lid material 2, 22 ... Biaxially stretched resin layer 3, 23 ... Adhesive layer 4, 24 ... Intermediate layer 4a ... First resin layer 4b ... Second resin layer 4c ... Third resin layer 5, 25 ... Peeling Layers 6, 26 ... Heat sealant layer 11 ... Carrier tape 12 ... Embossed portion 27 ... Antireflection film 28 ... Antistatic layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B32B 27/30 A 8413-4F B 8413-4F 101 8413-4F 27/32 103 8413-4F 27 / 36 8413-4F 27/40 8413-4F B65B 15/04 Z B65D 77/20 L

Claims (22)

[Claims] 1. A biaxially stretched resin layer, a heat sealant layer, and a release layer adjacent to the heat sealant layer and located between the biaxially stretched resin layer and the heat sealant layer.
A lid material comprising an intermediate layer adjacent to the release layer and located between the biaxially stretched resin layer and the release layer, wherein the heat sealant layer contains ethylene-vinyl acetate as a main component. 2. The lid member according to claim 1, wherein the heat sealant layer is formed on the entire one surface of the lid member. 3. The heat sealant layer is formed in a sea-island pattern on one surface of the lid member, and 1
The lid material according to claim 1, wherein the area of each sea-island pattern is in the range of 0.01 to 0.5 mm ² . 4. The intermediate layer has a density of 0.915 to 0.94.
0 g / cm ³ ethylene-α / olefin copolymer, styrene-butadiene block copolymer of styrene 50 to 90% by weight and butadiene 50 to 10% by weight, styrene 1
A hydrogenated product of a styrene-butadiene block copolymer of 0 to 50% by weight and 90 to 50% by weight of butadiene, and at least an ethylene-α-olefin copolymer and a styrene-butadiene block copolymer among high-impact polystyrene. The lid member according to any one of claims 1 to 3, which is formed of three or more kinds of resins. 5. The intermediate layer has a single layer structure and a density of 0.9.
70 to 30% by weight of a styrene-butadiene block copolymer of 30 to 70% by weight of an ethylene-α-olefin copolymer of 15 to 0.940 g / cm ³ , 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene. % With respect to 100 parts by weight of the resin composition, 5 to 30 parts by weight of hydrogenated product of styrene-butadiene block copolymer of 10 to 50% by weight of styrene and 90 to 50% by weight of butadiene, and high impact polystyrene 5 The lid material according to claim 4, wherein the lid material is formed of a resin composition to which -50 parts by weight is added. 6. The intermediate layer has a single layer structure and a density of 0.9.
70 to 30% by weight of a styrene-butadiene block copolymer of 30 to 70% by weight of an ethylene-α-olefin copolymer of 15 to 0.940 g / cm ³ , 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene. % Of a resin composition of 100% by weight, and 5 to 30 parts by weight of a hydrogenated product of a styrene-butadiene block copolymer of 10 to 50% by weight of styrene and 90 to 50% by weight of butadiene. The lid member according to claim 4, wherein the lid member is formed of a composition. 7. The intermediate layer has a single layer structure and a density of 0.9.
70 to 30% by weight of a styrene-butadiene block copolymer of 30 to 70% by weight of an ethylene-α-olefin copolymer of 15 to 0.940 g / cm ³ , 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene. % High-impact polystyrene 5 to 100 parts by weight of the resin composition
The lid material according to claim 4, wherein the lid material is formed of a resin composition to which -50 parts by weight is added. 8. The intermediate layer has a two-layer structure of a first resin layer and a second resin layer in contact with the heat sealant layer, and the first resin layer has a density of 0.915 to 0.940 g / cm ³ . The second resin layer is formed of an ethylene-α-olefin copolymer, and the second resin layer has an ethylene-α-olefin copolymer density of 0.915 to 0.940 g / cm ³ 30 to 70% by weight.
And 50 to 90% by weight of styrene and 50 to 10 of butadiene
Styrene-butadiene block copolymer with 70% by weight
10 to 50% by weight of styrene and 90 to 50% by weight of butadiene based on 100 parts by weight of the resin composition of 30 to 30% by weight.
The lid material according to claim 4, which is formed of a resin composition to which 5 to 30 parts by weight of a hydrogenated product of a styrene-butadiene block copolymer with is added. 9. The intermediate layer has a two-layer structure of a first resin layer and a second resin layer in contact with the heat sealant layer, and the first resin layer has a density of 0.915 to 0.940 g / cm ³ . The second resin layer is formed of an ethylene-α-olefin copolymer, and the second resin layer has an ethylene-α-olefin copolymer density of 0.915 to 0.940 g / cm ³ 30 to 70% by weight.
And 50 to 90% by weight of styrene and 50 to 10 of butadiene
Styrene-butadiene block copolymer with 70% by weight
5. The lid material according to claim 4, which is formed of a resin composition in which 5 to 50 parts by weight of high-impact polystyrene is added to 100 parts by weight of the resin composition of 30 to 30% by weight. . 10. The intermediate layer has a two-layer structure of a first resin layer and a second resin layer in contact with the heat sealant layer,
The first resin layer has a density of 0.915 to 0.940 g / cm ³
Formed of an ethylene-α / olefin copolymer of
The second resin layer has a density of 0.915 to 0.940 g / cm ^3.
Ethylene-α / olefin copolymer of 30 to 70% by weight
And 50 to 90% by weight of styrene and 50 to 10 of butadiene
Styrene-butadiene block copolymer with 70% by weight
10 to 50% by weight of styrene and 90 to 50% by weight of butadiene based on 100 parts by weight of the resin composition of 30 to 30% by weight.
5 to 30 parts by weight of a hydrogenated product of a styrene-butadiene block copolymer with
The lid member according to claim 4, wherein the lid member is formed of a resin composition to which 50 parts by weight is added. 11. The intermediate layer has a three-layer structure including a first resin layer, a second resin layer, and a third resin layer in contact with the heat sealant layer, and the first resin layer has a density of 0.915 to 0. 9
The second resin layer is formed of a 40 g / cm ³ ethylene-α-olefin copolymer, and the second resin layer has a density of 0.915 to 0.9.
40 g / cm ³ of ethylene-α / olefin copolymer 30
Of 70 to 30% by weight, 70 to 30% by weight of styrene-butadiene block copolymer of 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene, and the third resin layer has a density of 0. .915-0.940 g /
ethylene-.alpha. · olefin copolymer 30-70 wt% of cm ^3, styrene 50-90% by weight of butadiene 50
10 to 50% by weight of styrene and 90 to 50% of butadiene based on 100 parts by weight of the resin composition containing 70 to 30% by weight of the styrene-butadiene block copolymer with 10% by weight.
The lid material according to claim 4, which is formed of a resin composition to which 5 to 30 parts by weight of a hydrogenated product of a styrene-butadiene block copolymer with 5% by weight is added. 12. The intermediate layer has a three-layer structure of a first resin layer, a second resin layer, and a third resin layer in contact with the heat sealant layer, and the first resin layer has a density of 0.915 to 0. 9
The second resin layer is formed of a 40 g / cm ³ ethylene-α-olefin copolymer, and the second resin layer has a density of 0.915 to 0.9.
40 g / cm ³ of ethylene-α / olefin copolymer 30
Of 70 to 30% by weight, 70 to 30% by weight of styrene-butadiene block copolymer of 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene, and the third resin layer has a density of 0. .915-0.940 g /
ethylene-.alpha. · olefin copolymer 30-70 wt% of cm ^3, styrene 50-90% by weight of butadiene 50
It is formed of a resin composition in which 5 to 50 parts by weight of high-impact polystyrene is added to 100 parts by weight of the resin composition of 10 to 30% by weight of a styrene-butadiene block copolymer and 70 to 30% by weight. The lid material according to claim 4, wherein 13. The intermediate layer has a three-layer structure of a first resin layer, a second resin layer, and a third resin layer in contact with the heat sealant layer, and the first resin layer has a density of 0.915 to 0. 9
The second resin layer is formed of a 40 g / cm ³ ethylene-α-olefin copolymer, and the second resin layer has a density of 0.915 to 0.9.
40 g / cm ³ of ethylene-α / olefin copolymer 30
Of 70 to 30% by weight, 70 to 30% by weight of styrene-butadiene block copolymer of 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene, and the third resin layer has a density of 0. .915-0.940 g /
ethylene-.alpha. · olefin copolymer 30-70 wt% of cm ^3, styrene 50-90% by weight of butadiene 50
10 to 50% by weight of styrene and 90 to 50% of butadiene based on 100 parts by weight of the resin composition containing 70 to 30% by weight of the styrene-butadiene block copolymer with 10% by weight.
% Of hydrogenated styrene-butadiene block copolymer and 5 to 50 parts by weight of high-impact polystyrene, and 5 to 50 parts by weight of the resin composition. Item 4. The lid member according to item 4. 14. The intermediate layer has a density of 0.915 to 0.9.
40 g / cm ³ of ethylene-α / olefin copolymer 30
To 70 parts by weight, and 70 to 30 parts by weight of a styrene-butadiene block copolymer of 50 to 90% by weight of styrene and 50 to 10% by weight of butadiene are added to the resin composition. The lid member according to any one of claims 1 to 3. 15. The intermediate layer has a density of 0.915 to 0.9.
40 g / cm ³ of ethylene-α / olefin copolymer 30
To 70 parts by weight and 70 to 30 parts by weight of a styrene-butadiene block copolymer hydrogenated product of 10 to 50% by weight of styrene and 90 to 50% by weight of butadiene. The lid member according to any one of claims 1 to 3, wherein 16. The intermediate layer has a glass transition temperature of 40 ° C.
The lid material according to any one of claims 1 to 3, which is formed of the linear saturated polyester resin described above. 17. The lid member according to any one of claims 1 to 16, wherein the heat sealant layer contains 20% by weight or more of ethylene-vinyl acetate. 18. The inorganic compound comprising a thermoplastic resin, a metal, conductive fine particles, barium sulfate, silica, magnesium carbonate, aluminum hydroxide, magnesium hydroxide, silicates, mica and potassium titanate in a thermoplastic resin. 18. The lid material according to claim 1, which is a layer containing at least one kind of a fine particle group containing any of the above as a main component. 19. The thermoplastic resin forming the release layer contains at least one of a polyester resin, a polyurethane resin, a vinyl chloride-vinyl acetate copolymer resin, and an acrylic resin. The described lid material. 20. The lid member according to claim 1, further comprising an antireflection film on the biaxially stretched resin layer. 21. An antistatic layer is provided between the biaxially stretched resin layer and the antireflection film.
The lid material according to 0. 22. The lid material according to claim 1, wherein the total light transmittance is 75% or more and the haze value is 50% or less.