JP2002211575A - Barrier property in-molded label container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a barrier property in-molded label container wherein a cover material having top-surface seal-barrier properties retains proper peeling properties, and barrier properties can be improved, suppressing leak of oxygen from under a flange to the utmost. SOLUTION: A barrier injection-molded container body 20 having a flange 21 on its top surface is obtained by in-mold label molding a bottom surface barrier label 14 on the inner surface of a the bottom 24, and a side surface barrier label 12 on the outer surface of a body portion 22. In the in-mold label container 1 wherein a top surface seal barrier cover material 10 is sealed on the flange 21 of the container body 20, the cover material 10 is sealed within a width W of about 7 mm from the inside end edge I of the flange 21, and the edge I has a round shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a barrier in-mold label container which is mainly subjected to in-mold labeling by injection molding, and more particularly to a gas barrier which is almost completely formed by a sealing shape of a barrier lid material sealed on a top surface. TECHNICAL FIELD The present invention relates to a barrier-in-mold label container suitable for storing foods, medicines, and the like, which require a property.

[0002]

2. Description of the Related Art An in-mold label ring is used to set a label having a sealant layer in a mold in advance when molding a molded article such as a container by heating or melting or softening plastic such as blow molding, injection molding or sheet molding. This is a molding method in which the sealant layer of the label is fused to a molded article such as a container by the heat of the resin at the time of molding, thereby performing labeling simultaneously with molding.

[0003] In the in-mold label container obtained by the in-mold labeling, for example, contents such as baby food are stored, and as a container requiring gas barrier properties as much as possible, the opening of the label or the top surface is sealed. Barrier film (sheet) with gas barrier properties for the lid material to be sealed
For example, as shown in the side sectional view of FIG. 4, a flange (21) is provided at the top opening, and the bottom (2) is provided.
4) a bottom barrier label (14) on the inner surface and a torso (2)
Injection-molded container (2) obtained by in-mold label molding of side barrier label (12) on the outer surface of (2)
There is a barrier in-mold label container (1) in which the top surface seal barrier lid (10) is sealed on the flange (21) of (0).

In the conventional barrier in-mold label container (1), for example, when the inner edge (I) of the flange (21), that is, the inner edge, is sealed, the peak of the sealing strength is concentrated on this edge. If an appropriate peel (peeling at opening) strength is not obtained, or if the edge is cut, or if the dimensions of the flange (21) vary, the edge may be sealed. As shown in the schematic side cross-sectional view of FIG. 5, the sealing portion (32) between the top surface sealing barrier lid (10) and the flange (21) of the container is positioned several mm (2) near the center of the flange (21). ３3 mm). Therefore, the flow path of the gas (O ₂ ) from the outside air flows from the lower part of the flange (21) to the sealing part (32).
O passing through the non-seal portion (34) inside the O
To form a _second flow path (P), complete gas barrier property was not be obtained.

Incidentally, as a flow path of gas (O ₂ ) from the outside air, an O ₂ flow path (not shown) leading to the inside from a joint (not shown) of the side barrier label (12) and the above-mentioned flow path From the lower part of the flange (21)
O passing through the non-seal portion (34) inside the O
And _second flow path (P), but the bottom (24) through the body portion (22) from the end there are three of O ₂ flow path (Q) leading to the interior, of these the flange (21) The theoretical oxygen leak amount in the O ₂ flow path (P) passing from the lower part through the non-seal part (34) inside the seal part (32) to the inside occupies 60% or more of the whole. .

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art, and has as its object to provide a flange having an opening at the top surface and a barrier label at the bottom inner surface. And a barrier in-mold label container in which a top sealing barrier lid material is sealed to the flange of an injection molded container body obtained by in-mold label molding of a side barrier label and a side barrier label on the outer surface of the trunk. Barrier properties that maintain moderate peeling of the lid material, and improve the seal width, shape, flange shape, etc., to minimize oxygen leakage from the lower part of the flange as much as possible. It is to provide a mold label container.

[0007]

In order to achieve the above-mentioned object, according to the present invention, first, a flange is provided at an opening on a top surface, a bottom barrier label is provided on an inner surface of a bottom, and an outer surface of a trunk is provided on an inner surface. A barrier injection molded container body obtained by in-mold label molding of a side surface barrier label and a top surface barrier label, wherein the top surface seal barrier lid material is sealed to the flange. The inner edge of the seal of the conductive lid material is located at a position not exceeding the thickness of the container body wall from the inner edge of the flange or the inner edge. Things.

According to the first aspect of the present invention, the inner edge of the seal of the top surface sealing barrier lid material is located at the inner edge of the flange or at a position not exceeding the thickness of the container body wall from the inner edge. Since there is no non-seal portion on the inner edge side of the flange as in the related art, the O ₂ flow path passing from the lower portion of the flange to the inside through the non-seal portion inside the seal portion is blocked, and the gas barrier property is reduced. Thus, it is possible to provide a barrier in-mold label container having improved properties.

In the invention according to claim 2, the inner edge of the flange has an R-shape, which is the barrier in-mold label container according to claim 1.

According to the second aspect of the present invention, by forming the inside edge of the flange of the barrier-molded injection-molded container main body, that is, the inside edge into an R-shape, the sealing strength is not concentrated on the edge, and the flange is extended to the edge. Since the seal is uniformly and easily sealed, an appropriate peel strength can be obtained, and a barrier in-mold label container having more improved gas barrier properties can be obtained.

The above-mentioned R shape refers to a curved chamfered shape, and the inner edge of the flange refers to the R shape.
When no portion is provided, it literally refers to an edge inside the flange (on the container storage portion side), and when an R portion is provided, it refers to the position where the R portion inside the flange starts.

[0012]

Embodiments of the present invention will be described below. The present invention relates to an in-mold label container (1) in which a side barrier label (12) and a bottom barrier label (14) are in-mold labeled by blow or injection molding as shown in the side sectional view of FIG. Particularly, a top surface sealing barrier property which is sealed to the flange (21) of the top opening. It relates to an in-mold label container (1).

As shown in FIG. 1, the barrier in-mold label container of the present invention has a flange (2
Injection-molded container body having 1), wherein a bottom barrier label (14) is provided on the inner surface of the bottom (24) and a side barrier label (12) is provided on the outer surface of the body (22) by in-mold labeling. (20) In the barrier in-mold label container (1) in which the flange (21) is sealed with a top surface sealing barrier material (10), as shown in a schematic side sectional view of FIG. For example, the width (W) of the sealing portion (32) between the top surface sealing barrier material (10) and the flange (21) of the barrier injection molding container body (20) is equal to the outer edge of the flange (21). This is a barrier in-mold label container (1) from O) to the inner edge (I).

In the present invention, as shown in FIG. 2, for example, a flange (2) of a barrier injection molding container main body (20) is used.
This is a barrier in-mold label container (1) in which the inner edge (I) of 1), that is, the inner edge, has an R shape (curved chamfered shape).

As described above, according to the present invention, the sealing portion (32) between the top surface seal barrier lid material (10) and the flange (21) extends from the outer edge (O) to the inner edge of the flange (21). Up to the rim (I), since there is no non-seal portion inside the flange as in the related art, the O ₂ flow path (P) leading from the lower portion of the flange (21) to the inside is blocked by the seal portion (32), The barrier in-mold label container (1) having improved gas barrier properties can be obtained.

In the above case, the sealing portion (32) with the flange (21) extends from the outer edge (O) to the inner edge (I) of the flange (21). In addition, the inner edge of the seal portion (32) is
It is located at a position not exceeding the thickness of the wall of the container body (22) from the inner edge (I) of 1), and its width (W) is 7 mm.
It is sufficient if it is on the order.

Further, as shown in FIG.
1) the inner edge (I), i.e. the inner edge, with a radius in the cross section ranging from 0.3 to 3.0, preferably 0.5 mm
By forming a curved surface having a degree of curvature, the sealing strength is not concentrated on the inner edge (I), that is, the inner edge, and the sealing is uniformly and easily performed up to the edge, so that an appropriate peel strength is obtained. The barrier in-mold label container (1) having more improved gas barrier properties can be obtained. Depending on the relationship with the thickness of the container, if this R is too large, the width (W) of the seal portion (32) becomes small, and as a result, O ₂ passing from the lower part of the flange (21) to the inside is reduced.
When the flow path (P) is easily obtained, that is, the amount of oxygen leak increases and the gas barrier property cannot be improved, and when R is too small, the seal strength tends to concentrate on the inner edge (I), that is, the inner edge. As a result, an appropriate peel strength cannot be obtained, which is not preferable. The width (W) of the seal portion (32) is preferably 3 mm or more in order to obtain the completeness of the seal (sealability). Also, in order for a person to be able to open it by hand, the sealing surface should be 20 mm or less,
It is preferably 10 mm or less, and more preferably about 7 mm as described above.

The top surface sealing barrier material (1) constituting the barrier in-mold label container (1) of the present invention.
0), a gas barrier sheet (film) used for the side barrier label (12) and the bottom barrier label (14), for example, as shown in the side sectional view of FIG. ), A gas barrier layer (17) in the middle, and a sealant layer (18) in the innermost layer in consideration of fusing property or sealing property with the injection resin. Each layer is formed by, for example, a dry lamination method, an extrusion lamination method, or an extrusion method. In general, a laminate is formed by laminating by a coating method or the like.

As the printing base material layer (16) constituting the gas barrier sheet (film), for example, paper having a white surface and suitable for multicolor printing can be used, and the basis weight is 50 g / m2.
² to 120 g / m ^2, preferably about 75 g / m ² to 1
Both art papers, single art papers, or double-sided, single-sided coated papers of about 00 g / m ² can be suitably used.
In some cases, for example, a polyethylene terephthalate film (PET), a biaxially stretched nylon film (ONy) or a stretched polypropylene film (OPP) having a thickness of about 12 μm can be used. In addition,
It is preferable that such a plastic film is used as a label when the container is subjected to retort and boil sterilization.

The above gas barrier sheet (film)
For example, an aluminum foil having a thickness of about 7 μm is used as the gas barrier layer (17). However, the environmental load related to waste disposal in recent years is large, and the contamination of metal-based foreign matter by a metal detector after filling the contents is performed. Due to the problem that inspection is impossible, an aluminum-less gas barrier layer (17) has been applied. For example, a polyethylene terephthalate film having a thickness of about 12 μm, on which aluminum is vapor-deposited, or an inorganic oxide in consideration of transparency. Aluminum oxide such as Al ₂ O ₃ , Si
There is a ceramic vapor-deposited film in which a silicon oxide such as O ₂ or SiO is vapor-deposited by a physical vapor deposition method or a chemical vapor deposition method, and the thickness of these aluminum vapor-deposited or ceramic vapor-deposited layers is preferably about 5 to 50 nm. Furthermore, even in this ceramic vapor-deposited film, the polyethylene oxide terephthalate film is anchor-coated because the aluminum oxide has an excellent gas barrier property and the vapor-deposited layer of the aluminum oxide prevents the gas barrier property from being deteriorated by cracks or the like caused by rubbing. As the layer, for example, at least an acrylic polyol, an isocyanate compound, and a general formula: R′Si (OR) ₃ (where R ′ is an alkyl group, a vinyl group, or a glycyoxypropyl group, and R is an alkyl group) A composition containing a trifunctional organosilane or a hydrolyzate of an organosilane, or a composition having the general formula: M (OR) _n (where M is a metal element, and R is an alkyl group such as CH ₃ or C ₂ H ₅₎ , N is the oxidation number of the metal element) or a metal alkoxide represented by For example, a water-soluble polymer, (a) one or more metal alkoxides and hydrolysates thereof, b) An aqueous solution containing at least one of tin chloride or a coating agent mainly containing a water / alcohol mixture can be used. That is, by covering the deposited layer of the aluminum oxide with the anchor coat layer and the coating layer in such a manner, it can be suitably used as a material for preventing cracks or the like caused by rubbing of the deposited layer.

Also, a sealant (18) as the innermost layer
Examples include linear low-density polyethylene (LLDPE) and low-density polyethylene (LDP)
E), polyolefin-based resins such as high-density polyethylene (HDPE) and unstretched polypropylene (CPP) are preferably used. Particularly, as the top surface sealing barrier lid material (10), the adhesive strength and the peel strength of these resins alone are used. In some cases, for example, the polyolefin resin may be further mixed with an incompatible component made of polystyrene, polybutene, or the like. Further, a hot melt adhesive composed of an ethylene-vinyl acetate copolymer resin, an ethylene-acrylic acid copolymer resin, or the like is applied in an amount of 15 to 25 g / m ^2.
The sealant layer (18) allows sufficient sealing and peel-opening with the flange (21) of the injection molded container body (20).

The resin for the injection molded container body (20) constituting the barrier in-mold label container (1) of the present invention is a thermoplastic resin which can be injection molded, for example, polypropylene resin, polyethylene resin, polystyrene. Resins and the like are mentioned, and are appropriately selected depending on the kind of the contents and the like.

[0023]

Next, the present invention will be described in detail with reference to examples. <Example 1> As shown in FIG.
6) A polyethylene terephthalate film (PET) having a thickness of 12 μm and an intermediate gas barrier layer (1)
7) As an example, an anchor coat layer having the following composition is provided on one side of a polyethylene terephthalate film (PET) having a thickness of 12 μm, and a 30 nm-thick aluminum oxide vapor-deposited layer is provided thereon. Was provided with a coating layer having the following composition to obtain a transparent film having excellent gas barrier properties. <Components of anchor coat layer> 2- (epoxycyclohexane) ethyltrimethylsilane (hereinafter referred to as E
2.5 times the amount (weight ratio) of an acrylic polyol was mixed with ETMS, and a tin chloride / methanol solution (adjusted to 0.003 mol / g) was added so as to be 1/135 mol with respect to the EETMS. Then, tolylene diisocyanate was mixed so that the NCO group was equivalent to the OH group of the acrylic polyol to obtain a coating liquid for the anchor coat layer. <Components of coating layer> To 10.4 g of tetraethoxysilane, 89.6 g of hydrochloric acid (0.1 N) was added, and the mixture was stirred for 30 minutes, and a solution having a hydrolyzed solid content of 3 wt% (in terms of SiO ₂ ),
The coating solution of the coating layer was obtained by mixing a polyvinyl alcohol solution.

Of the innermost sealant layer (18), the sealant layer (18) for the top surface sealing barrier lid material (10) has a thickness of 35 μm obtained by mixing polybutene which is an incompatible component with polyethylene. Easy peel film: trade name CF7601 (manufactured by Toray Gosei Co., Ltd.) with side barrier label (12) and bottom barrier label (14)
As a sealant layer (18), a 35 μm-thick non-stretched polypropylene film is used, and each layer is made of a polyester / urethane-based adhesive for dry lamination: A-515 / A-50 (manufactured by Takeda Pharmaceutical Co., Ltd.) ) And cut into a predetermined size to obtain a top seal barrier lid material (10), a side barrier label (12), and a bottom barrier label (14).

Subsequently, as shown in FIG. 1, the side barrier label (12) and the bottom barrier label (14) obtained above are obtained.
Is placed on the side and top of the bottom of the mold, injecting polypropylene resin into the mold to perform in-mold label molding,
A barrier injection molded container (20) having an inner volume of 100 ml was obtained.

Subsequently, the inner edge (I) of the flange (21) of the barrier injection molded container (20) obtained above is R
The surface of the sealant layer (18) of the top surface seal barrier lid material (10) obtained above is heat-sealed to the flange (21) having an R shape of 0.5 to form a seal portion (32) having a width of 7 mm. ) Was formed and the container opening was sealed to obtain a barrier in-mold label container (1).

Example 2 Top Surface Sealing Barrier Lid (1)
A barrier in-mold label container (1) was obtained in the same manner as in Example 1 except that a 9 μm-thick aluminum foil was used as the gas barrier layer (17) for 0).

COMPARATIVE EXAMPLE 1 As shown in FIG. 5, except that the top surface sealing barrier material (10) and the sealing portion (32) of the flange (21) were set to a width of 2 mm at substantially the center of the flange (21). In the same manner as in Example 1, a barrier in-mold label container (1) was obtained.

<Comparative Example 2> As shown in FIG. 5, the top surface sealing barrier material (10) and the sealing portion (32) of the flange (21) were made to have a width of 2 mm at substantially the center of the flange (21). In the same manner as in Example 2, a barrier in-mold label container (1) was obtained.

Container 1 of barrier in-mold label container (1) obtained in Examples 1 and 2 and Comparative Examples 1 and 2
The oxygen permeation amount (cc / pkg · day) per piece was measured and evaluated for gas barrier properties. Further, the easy peel property of the top surface sealing barrier lid material (10) was evaluated. The results are shown in Table 1.

[0031]

[Table 1]

According to Table 1, the barrier properties of Examples 1 and 2 in which the wide seal portion (32) was used, compared with the barrier properties of the in-mold label containers of Comparative Examples 1 and 2 in which the seal portion (32) was narrow. In the in-mold label container, the oxygen permeation amount was surely reduced, and the gas barrier property was improved. Further, even in the top surface sealing barrier lid material (10) of the first and second embodiments in which the sealing portion (32) is widened by forming the inner edge of the flange into an R shape, the easy peel property at the time of opening can be maintained. there were. In addition, the thing which used the aluminum foil for the gas barrier layer (17) of the top surface sealing barrier lid material (10) was excellent in the whole gas barrier property compared with the ceramic vapor deposition film.

[0033]

As described above, the present invention has the following effects. That is, the top of the barrier injection-molded container body obtained by in-mold label molding of a bottom barrier label on the bottom inner surface and a side barrier label on the trunk outer surface having a flange at the top opening, and a top surface seal on the flange. In the barrier in-mold label container in which the barrier lid material is sealed, the top surface seal has an inner edge of the seal of the barrier lid material, the inner edge of the flange or the thickness of the container body wall from the inner edge. Position, and there is no non-seal part on the inner edge side of the flange as in the past,
O ₂ flow path from the lower portion of the flange is cut off, it is possible to produce a barrier in-mold label container gas barrier property is improved.

Further, by forming the inner edge of the flange, that is, the inner edge into an R shape, the sealing strength is not concentrated on the edge, and the sealing is uniformly and easily performed to the edge, so that an appropriate peel strength is maintained. Thus, a barrier in-mold label container having improved gas barrier properties can be obtained.

Therefore, the present invention exerts an excellent practical effect as a barrier in-mold label container for accommodating a baby food or the like and requiring strong gas barrier properties (oxygen and water vapor barrier properties).

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a barrier in-mold label container of the present invention in a side cross section.

FIG. 2 is a cross-sectional side view schematically illustrating one embodiment of the barrier in-mold label container of the present invention.

FIG. 3 is a side cross-sectional view for explaining an example of a top seal barrier lid, a side barrier label, and a bottom barrier label that constitute the barrier in-mold label container of the present invention.

FIG. 4 is an explanatory view showing an example of a conventional barrier in-mold label container in a side cross section.

FIG. 5 is a side sectional view schematically illustrating one example of a conventional barrier in-mold label container.

[Explanation of symbols]

1 barrier in-mold label container 10 ceiling seal barrier lid material 12 side barrier label 14 bottom barrier label 16 printing substrate layer 17 gas barrier layer 18 sealant layer 20 {Barrier Injection Molded Container Main Body 21} Flange 22} Body 24} Bottom 32 {Seal Part 34} Non-Seal Part I ‥‥ Inner Edge O ‥‥ Outer Edge P ‥‥ From the bottom of the flange O ₂ flow path W ‥‥ seal portion of the width from the O ₂ flow path Q ‥‥ bottom

Claims (2)

[Claims] 1. A barrier injection-molded container main body obtained by in-mold label molding of a top surface opening with a flange and a bottom barrier label on a bottom inner surface and a side barrier label on a trunk outer surface. In the barrier in-mold label container in which the top seal barrier lid material is sealed, the inner edge of the seal of the top seal barrier lid material is
A barrier in-mold label container characterized by being located at the inner edge of the flange or at a position not exceeding the thickness of the container body wall from the inner edge. 2. The barrier in-mold label container according to claim 1, wherein the inner edge of the flange is rounded.