JP2012030843A - Lid material of beverage container, beverage container using the lid material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lid material of a beverage container which uses no metal like aluminum foil as a composing material of the lid material of the beverage container, which has superior preservability of the content in the beverage container, and has an adequate piercing property of a straw or the like, and to provide the beverage container using the lid material.SOLUTION: The lid material of the beverage container seals an upper opening part of the beverage container and can be pierced by the straw. The lid material comprises a laminated structure of a film base material layer, a patten ink layer, a light shielding layer, an adhesive layer, and a thermoplastic resin layer. The film base material layer has polyester as a principal polymer component, total light transmission of the lid material of the beverage container is 1-25%, the piercing strength of the lid material of the beverage container is 3-10 N measured by the Food Sanitation Law test method on the strength, the seal adhesive strength of the thermoplastic resin layer with the beverage container measured by JIS-Z1707 is 5 N/15 mm-15 N/15 mm.

Description

TECHNICAL FIELD The present invention relates to a lid for a beverage container, and more specifically, a beverage container having a straw piercing suitability composed of a resin-based material obtained by removing a metal such as an aluminum foil from a constituent material of the lid. The present invention relates to a lid material and a beverage container using the lid material.

As a container filled with beverages such as juices, coffee drinks, milk component blended drinks, etc., a form sold in a state of being filled in a plastic container is known. In this case, a sheet-like lid is formed at the mouth of the plastic container, and the innermost layer of the lid and the flange of the plastic container are bonded by heat sealing. Is sealed. In addition, a plastic cover is often mounted on the cover for the purpose of strengthening design and packaging strength. When drinking, cover with the cover still attached. The contents are often drunk by inserting a straw or the like into the lid material from a straw hole provided in the lid. Therefore, the lid material is required to have a so-called piercing property of the lid material that penetrates the lid material by piercing with a straw or the like.

  As the lid material, for example, as described in Patent Document 1, a base material made of a resin film or paper alone or a composite, a laminate made of an aluminum foil, a heat sealing layer, and a straw only on the resin film base material. The purpose is to provide a penetration cut for piercing and improve the piercing suitability of a straw or the like.

However, since the structure includes an aluminum foil, when the plastic container is used as an adherend of the lid, it is necessary to separate the plastic container and the lid from each other at the time of disposal. Moreover, since the penetration cut | interruption is made in the resin film base material, the printability to a resin film base material and the lamination suitability are insufficient. Furthermore, in areas other than the through cut, the ability to pierce a straw or the like cannot be obtained. Therefore, in a distribution form using a cover lid, it is necessary to remove the cover lid and insert a straw into a predetermined cut portion.

  In addition, as a lid material, for example, as in the lid material described in Patent Literature 2, an aluminum foil and a sealant resin layer are generally laminated using a stretched plastic film as a front substrate.

However, there is a description that a biaxially stretched polyester film having a thickness of 12 μm or less is used as the stretched plastic film of the present lid material, and it is difficult to obtain a sufficient puncture suitability for practical use within the scope of the present invention. In addition, since aluminum foil is laminated, it is necessary to separate and discard the container and the lid material when disposing of the container after use. Is often cumbersome and often not disposed of separately.

Japanese Utility Model Publication No. 63-180557 JP 2008-80769 A

Moreover, it is common to use the biaxially stretched film or aluminum foil which has polyethylene terephthalate (PET) as a main component, and the base material which bonded these together for the resin film base material of the lid | cover material of a drink container. It is.

However, even if the biaxially stretched PET film is a thin film, it exhibits a tough strength due to crystallization by stretching orientation, and therefore is inferior in piercing suitability such as a straw in this application. In addition, if it is a single-layer aluminum foil base material, the piercing suitability of a straw or the like is good, but a thickness of 20 μm or more is required to give physical strength such as transportability and drop resistance, so a straw etc. The effect of improving the piercing suitability is not sufficient, and it is not appropriate in terms of cost and environment. Furthermore, when the container is discarded after use, the container and the lid need to be separated, and the suitability as a printing substrate is poor.

Cellophane is generally known as a film excellent in piercing suitability such as a straw. However, since cellophane has a hygroscopic property, various physical properties vary depending on the season, so that it is difficult to maintain a certain quality of the filling when used as a film for a lid of a beverage container.

In addition, a uniaxially oriented polyester film (Japanese Patent Publication No. 55-8551), a polyethylene terephthalate film copolymerized with a diethylene glycol component, etc. (Japanese Patent Publication No. 56-50692), a low molecular weight polyester blended film (Japanese Patent Publication No. 56-50692), etc. Has been proposed.
However, in the above-mentioned uniaxially oriented polyester film, the orientation direction can be easily cut linearly, but there is a problem that it is difficult to cut other than the orientation direction, and in the diethylene glycol component and the low molecular weight polyester blended film, The original properties of polyethylene terephthalate were impaired, and film formation suitability, processability, and impact resistance were insufficient, and were not practical.

  Therefore, the present invention does not use a metal such as aluminum foil from the constituent material of the beverage container lid material, is excellent in the preservation of the contents of the beverage container, and has a suitability for piercing such as a straw. An object of the present invention is to provide a beverage container using the lid.

The present invention relates to a lid for a beverage container that seals the upper opening of the beverage container and can be pierced with a straw, wherein the lid for the beverage container comprises a film base layer, a pattern ink layer, and a light shielding ink layer , Consisting of a laminated structure of an adhesive layer and a thermoplastic resin layer, wherein the film base layer is a polymer component mainly composed of polyester, and the total light transmittance of the lid of the beverage container is 1% or more and 25% or less, The piercing strength of the lid of the beverage container measured by the food hygiene law strength test method is 3N or more and 10N or less, and the seal adhesive strength between the thermoplastic resin layer measured by JIS-Z1707 and the beverage container is It is a lid | cover material of the container for drinks characterized by being 5N / 15mm or more and 15N / 15mm or less.

  Moreover, the adhesive layer is a gas barrier adhesive layer made of an epoxy resin. In addition, the beverage container is characterized in that the content of the container is a milk component-blended beverage that requires cold and warm circulation. Furthermore, it is a beverage container characterized by having a covering lid on the lid material of the beverage container.

When the beverage container lid according to the present invention is used, it can be disposed of without separating the plastic container and the lid material by using no metal such as aluminum foil, and the metal such as aluminum foil is used. Even if it does not, it is excellent in the preservation | save property of the content of the container for drinks, and it can have straw piercing suitability.

Sectional drawing of the lid | cover material of the container for drinks concerning this invention Sectional drawing of the lid | cover material of another drink container concerning this invention

  Hereinafter, the present invention will be described in detail. As shown in FIG. 1, the beverage container lid 6 of the present invention is laminated in the order of a film base layer 1, a light shielding ink layer 2, an adhesive layer 3, and a thermoplastic resin layer 4.

Said film base material layer 1 becomes the outermost layer of the lid | cover material 6 of a drink container, and when using it as the cover material 6 of the drink container concerning this invention, it displays the content of a product and appeals to a buyer. Since it has a role, a resin having good straw piercing suitability without impairing printing suitability and laminate suitability is preferable.

As this resin, in a film in which at least two types of polyester resin layers having different melting points are laminated, the outermost layer is a layer having a high melting point, and there is no molecular orientation of the low melting point polyester layer as an intermediate layer. The feature film can be used.

Examples of the polyester resin having a higher melting point include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and copolymers mainly composed of these components. Polyesters having terephthalic acid as the main acid component and ethylene glycol as the main alcohol component are preferred.

Moreover, as a polyester resin having a lower melting point, terephthalic acid such as terephthalic acid-isophthalic acid-ethylene glycol copolymer, terephthalic acid-ethylene glycol-neopentyl glycol copolymer, and the like are mainly composed of terephthalic acid and ethylene glycol. A polyester containing an acid component and / or other glycol component as a copolymer component is preferred. Other acid components include aliphatic dibasic acids (for example, adipic acid, sebacic acid, azelaic acid) and aromatic dibasic acids (for example, isophthalic acid, diphenyldicarboxylic acid, 5-tert-butylisophthalic acid, 2,2,6,6-tetramethylbiphenyl-4,4-dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,1,3-trimethyl-3-phenylindene-4,5-dicarboxylic acid) . Glycol components include aliphatic diols (eg neopentyl glycol, diethylene glycol, propylene glycol, butane diol, hexane diol), alicyclic diols (eg 1,4-cyclohexanedimethanol) or aromatic diols (eg Renglycol, bis (4-β-hydroxyphenyl) sulfone, 2,2- (4-hydroxyphenyl) propane derivative) are used.
The polyester resin having a higher melting point is not particularly limited as long as it has a melting point higher by 10 ° C. or more, preferably 20 ° C. or more than the polyester resin having a lower melting point.
By laminating at least two kinds of polyester resin layers having different melting points, and setting the heat setting temperature after stretching to an intermediate value between the two melting points, the strength derived from the orientation of the low melting point layer disappears, such as a straw. It is possible to impart piercing suitability.

As for the thickness of the film base material layer 1, 9 micrometers or more and 25 micrometers or less are preferable. If it is 9 μm or less, the physical strength of the film substrate 1 is lowered. On the other hand, when the thickness is 25 μm or more, the suitability for piercing such as a straw is deteriorated.

Although not shown in the figure, a pattern ink layer with a pattern can be provided on one side of the film base layer 1. The pattern ink layer can be provided between the film substrate layer 1 and the light-shielding ink layer 2 or on the outermost surface of the film substrate layer 1, and gravure ink, offset ink and flexo ink are used to print each ink. Can be provided.

The light-shielding ink layer 2 is provided on the innermost layer side of the film base layer 1 and can block light from the outside for the purpose of protecting the contents of the beverage container.
The ink of the light-shielding ink layer 2 includes a colorant, a vehicle, an auxiliary agent, and the like. As the colorant for the light-shielding ink layer 2, a dye or a pigment is used. A pigment is a white or colored inorganic compound and organic compound that are finely dispersed in a vehicle.
As specific examples of the pigment, a black pigment, a red pigment, a white pigment, or a mixture of these pigments can be used.

The vehicle is composed of a resin / solvent, and its role is to uniformly transfer the colorant to the substrate to be printed.

The auxiliary agent is within a range that does not deviate from the purpose of the light-shielding ink layer 2, for example, a dispersant for improving the wettability of the pigment and the resin, or an antioxidant or an ultraviolet absorber that prevents the resin or the like from being deteriorated by light or heat. Etc.
The light-shielding ink layer 2 may have a multilayer structure. For example, a white ink layer using a white pigment can be laminated on a sepia ink layer in which a black pigment and a red pigment are mixed.
In order to improve the adhesion between the ink used in the light-shielding ink layer 2 and the film substrate layer 1, it is desirable to use a urethane / vinyl chloride / vinyl acetate copolymer resin system as the resin system of the ink.

The adhesive layer 3 may be a two-component urethane adhesive using a polyurethane resin having an NH group or an NH ₂ group as a main component and a polyisocyanate compound or a modified product thereof as a curing agent. Good adhesion is achieved by mixing the two so that the ratio of the NCO group in the curing agent to the active hydrogen group in the main agent (for example, NH group, NH ₂ group or OH group) is in the range of 1-20. To do. Moreover, when preparing an adhesive agent, an appropriate amount of additives such as the urethanization catalyst as described above, other silane coupling agents, and anti-aging agents can be blended as necessary to accelerate the reaction.

  Further, the adhesive layer 3 may be replaced with a barrier adhesive layer 4. (See FIG. 2) The barrier adhesive layer 4 has a role of preventing the odor of the ink used in the light-shielding ink layer 2 from being transferred to the contents. As a specific example of the barrier adhesive layer 4, a two-component mixed epoxy adhesive obtained by mixing two liquid agents composed of a main agent (A agent) and a curing agent (B agent) can be used. An epoxy resin can be mainly used as the main agent, and a polyamide resin or a polythiol resin can be mainly used as the curing agent.

The adhesive layer 3 or the barrier adhesive layer 4 is preferably bonded to the surface of the film base layer 1 on which the light-shielding ink layer 2 is provided and the thermoplastic resin layer 4 described later using a non-solvent lamination method.
Since the organic solvent is not used in the non-solvent lamination method, the residual solvent after bonding does not migrate to the contents of the container and can maintain a good flavor.

The thermoplastic resin layer 4 is a resin layer that can be heat-sealed. Examples of the resin include polyethylene having an easy peel property with a polypropylene beverage container, and polyolefin obtained by polymerizing polypropylene. . In particular, when the content is a milk beverage, polystyrene (PS) and ethylene / vinyl acetate copolymer (EVA) are not preferred as resin components because of compliance with eluate regulations according to the ordinance of milk and the like.

This resin layer is composed of a single layer or multiple layers, and is peeled at the cohesive failure of the interlayer or innermost layer or at the container interface, and the lid material is opened from the container.

  The seal adhesive strength between the thermoplastic resin layer 4 and the beverage container needs to be 5 N / 15 mm or more and 15 N / 15 mm or less.

  By setting the seal adhesive strength to 5 N / 15 mm or more, the seal adhesive strength can be secured, and it can withstand impacts such as dropping during distribution. Moreover, especially about coffee drinks and fermented milk, since it will be in the pressurization state by the carbon dioxide generation | occurrence | production after filling, the sealing performance which bears this can be ensured.

  By making the seal adhesive strength 15N / 15mm or less, the lid of the beverage container can be easily peeled off from the container, and when drinking, the mouth of the container flange is put directly on the container, or when it is discarded In addition, the lid of the beverage container can be easily separated from the container. When the seal adhesive strength is 15 N / 15 mm or more, the lid of the beverage container breaks and the film base layer 1 and the light-shielding ink layer 2 are peeled off. Can not be peeled off.

The lid for the beverage container of the present invention needs to have a total light transmittance of 1% to 25%. The total light transmittance was measured using JIS K-7105. Specifically, the transmittance integrated at all wavelengths using a light source close to natural light is shown. When the pattern ink layer is laminated in addition to the light-shielding ink layer 2, there is a possibility that regions having different transmittances may be generated in the lid of the beverage container. Therefore, the transmittance of the entire surface of the lid of the beverage container The average value of

  When the total light transmittance is 1% or less, the lamination thickness of the ink of the light-shielding ink layer 2 or the content of the pigment contained in the light-shielding ink layer 2 is increased, and the cohesive force of the light-shielding ink layer 2 is increased. Therefore, the laminate strength between the film base material layer 1 and the light-shielding ink layer 2 cannot be ensured. On the other hand, when a small amount of a special pigment having high light shielding properties is used, the flavor and safety of the contents may be affected due to problems of odor and hygiene.

  If the total light transmittance is 25% or more, vitamins, milk fat, pigments, and other components that are altered or decomposed by light, such as vitamins contained in the beverage filling the container, cannot be retained, and the quality can be maintained. I can't.

Moreover, the lid material of the beverage container of the present invention is required to have a puncture strength of 3N or more and 10N or less. The puncture strength is measured using the food hygiene law strength test method. Specifically, the intensity peak value is shown when a 0.5 mmR hemispherical needle is used and pierced from the film base material layer 1 side at a piercing speed of 50 mm / min.

  By setting the puncture strength to 3N or more, it is possible to impart distribution resistance such as drop of the container.

  By setting the puncture strength to 10 N or less, it is possible to easily pierce the straw into the lid member, and it is particularly desirable that the puncture strength is 3 N or more and 5 N or less.

It is preferable to provide a covering lid on the lid of the beverage container of the present invention after the lid of the beverage container of the present invention is bonded to the plastic container filled with the milk beverage by heat sealing.
By providing the cover lid, deformation of the container mouth can be reduced, and impact resistance when the container is dropped can be improved.

Hereinafter, the present invention will be described in more detail with reference to examples. The following were used as each material.
Film base layer: PET film (Tearfine TF110 14 μm manufactured by Toyobo Co., Ltd.)
-Light-shielding ink layer: Sepia ink layer (Toyo Ink Manufacturing Co., Ltd .; Fine Star 92 Black and Toyo Ink Manufacturing Co., Ltd .; Fine Star 16 Red) mixed with a white ink layer (Sakata Inx Co., Ltd .; Bell Color 115D White) Laminated / Adhesive layer: Two-component mixed urethane adhesive (Toyo Morton ADN369)
-Barrier adhesive layer: Two-component mixed epoxy adhesive (Mitsubishi Chemical Gas Co., Ltd. Maxive)
-Thermoplastic resin layer: A resin layer based on polyethylene and laminated with a resin obtained by polymerizing polyethylene and polypropylene (VMX-XB16C 30 μm, manufactured by J Film Co., Ltd.)
Pattern ink layer: Fine Star 23/16 Orange (manufactured by Toyo Ink Manufacture), Fine Star 23/3 yellow (manufactured by Toyo Ink Manufacture), and Fine Star 23/3 beige (manufactured by Toyo Ink Manufacture) are used.

For the light-shielding ink layer and the pattern ink layer, each ink is diluted with a solvent, and the viscosity is 20 seconds with Zahn cup No. 3. Especially for the light-shielding ink, a screen gravure plate having a plate depth of 35 μm is used on the film base layer. Formed on the front of the product placement section. Next, a thermoplastic resin layer was laminated on the surface of the film base layer on which the light-shielding ink layer and the pattern ink layer were provided using a non-solvent lamination method. The application amount of the adhesive layer applied by this non-solvent lamination method is 1.7 g / m ² . Next, after aging at 38 degrees for 2 days, a lid for a beverage container of the present invention was produced.

  Further, the adhesive layer can be replaced with a gas barrier adhesive layer.

  Table 1 shows the total light transmittance, puncture strength, seal adhesive strength, distribution environment, and presence / absence of a cover.

Examples 4 to 7 in Table 1 are comparative examples of the present invention.
〔Evaluation methods〕
A plastic container was filled with the milk beverage as the contents, and the lid of the beverage container of the present invention was heat sealed at 160 ° C. for 1 second. Then, the following evaluation was performed. The results are shown in Table 2.

(1) Preservability: When the filled product is stored for 2 weeks in a cool / warm environment and has no off-flavor: ○
(2) Puncture suitability: When piercing is possible with a straw: ○
(3) Openability: When the lid of the beverage container of the present invention is peeled from the container, it can be completely peeled between the sealant layer of the lid of the beverage container of the present invention and the container: ○

DESCRIPTION OF SYMBOLS 1 Film base material layer 2 Light-shielding ink layer 3 Adhesive layer 4 Thermoplastic resin layer 5 Barrier adhesive layer 6 Beverage container lid

Claims (4)

In the lid of a beverage container that seals the upper end opening of the beverage container and can be pierced with a straw, the lid of the beverage container includes a film base layer, a pattern ink layer, a light-shielding ink layer, an adhesive layer, It consists of a laminated structure of thermoplastic resin layers, the film base layer is made of polyester as a main polymer component, and the total light transmittance of the lid of the beverage container is 1% or more and 25% or less, and the strength of the Food Sanitation Law The puncture strength of the lid of the beverage container measured by the test method is 3N or more and 10N or less, and the seal adhesive strength between the thermoplastic resin layer measured by JIS-Z1707 and the beverage container is 5N / 15 mm. As mentioned above, the lid | cover material of the container for drinks characterized by being 15 N / 15mm or less. The lid for a beverage container according to claim 1, wherein the adhesive layer is a gas barrier adhesive layer made of an epoxy resin. The container for beverages according to claim 1 or 2, wherein the content of the container is a milk component-blended beverage that requires cold and hot circulation. The beverage container according to claim 1, further comprising a covering lid on the lid material of the beverage container.

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