JP3780075B2 - Easy-open composite film for heat-resistant containers - Google Patents
Easy-open composite film for heat-resistant containers Download PDFInfo
- Publication number
- JP3780075B2 JP3780075B2 JP23316997A JP23316997A JP3780075B2 JP 3780075 B2 JP3780075 B2 JP 3780075B2 JP 23316997 A JP23316997 A JP 23316997A JP 23316997 A JP23316997 A JP 23316997A JP 3780075 B2 JP3780075 B2 JP 3780075B2
- Authority
- JP
- Japan
- Prior art keywords
- layer
- thickness
- composite film
- heat
- resin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Landscapes
- Closures For Containers (AREA)
- Laminated Bodies (AREA)
Description
【０００１】
【発明の属する技術分野】
本発明は、複合フイルムに係り、特にそのシール層が通常のポリオレフィン系樹脂に限らず、ポリカーボネート樹脂、熱可塑性ポリエステル樹脂等の高耐熱性樹脂にも優れたヒートシール性を有し、流通過程における密封性に優れるとともに、使用時には容易に剥離できる耐熱容器用の蓋材や底材に好適に使用できる易開封性複合フイルムに関する。
【０００２】
【従来の技術とその課題】
食品を深絞り包装体に充填し、窒素ガス等の不活性ガスを充満してなるガスパック包装体においては、密封性と易開封性を兼ね備えた包材が要求されている。従来、このような用途に使用される易開封性複合フイルムのシール層は通常のポリオレフィン系樹脂が使用されているため、電子レンジ用の耐熱容器では、その構成樹脂として使用されているポリカーボネート樹脂や熱可塑性ポリエステル樹脂等の高耐熱性樹脂との完全密封性が保持でき難いという問題があった。
【０００３】
【課題を解決するための手段】
本発明は、上述の問題点を解消できる密封性と易開封性を兼ね備えた易開封性複合フィルムを見出したものであり、その要旨とするところは、ヒートシール層がエチレングリコール、テレフタル酸及び１，４−シクロヘキサンジメタノールからなる共重合体からなり、前記ヒートシール層の厚みが２〜１０μｍの範囲であるとともに、前記ヒートシール層と隣接する第２層がポリオレフィン系接着樹脂からなる層であり、前記第２層に隣接する第３層がポリアミド樹脂からなる層であり、かつ前記ヒートシール層と前記第２層の界面で剥離することを特徴とする耐熱容器用易開封性複合フィルムにある。
【０００４】
【発明の実施の形態】
以下、本発明をさらに詳細に説明する。
本発明において、ヒートシール層に設ける非晶性ポリエステルは、エチレングリコール、テレフタル酸及び１，４−シクロヘキサンジメタノールからなる共重合体であり、非晶性ポリエステルの例としては、イーストマン・ケミカル社製のＰＥＴＧ６７６３（ガラス転移点８１℃）が好適に使用できる。
【０００５】
ここで、ヒートシール層の厚みは２〜１０μｍの範囲とする必要があり、厚みが２μｍ未満ではヒートシール時に溶融した樹脂がシールの圧力により分断され完全密封されない可能性があり、１０μｍを越えるものでは剥離時にシール部端でシール層が切れずシール部以外の箇所まで層間の剥離が進んでしまい剥離面に繊維状ないし膜状にシール層が残るため、剥離外観が悪くなるという問題がある。
【０００６】
上記の非晶性ポリエステル樹脂からなるヒートシール層と隣接する層には、通常ポリオレフィン系接着樹脂が設けられ、このポリオレフィン系接着樹脂としては不飽和カルボン酸またはその誘導体から選ばれた少なくとも一種のモノマーをグラフトした酸変性ポリオレフィン樹脂が好適に使用でき、ヒートシール層との界面で剥離される。
【０００７】
本発明の複合フイルムには上記非晶性ポリエステル層と、それに隣接する接着樹脂層の他に、ポリアミド樹脂、エチレン酢酸ビニル共重合ケン化物樹脂、ポリオレフィン系樹脂等を共押出することが可能であり、また該複合フイルムのシール層の反対面に、延伸ポリエステルフイルム、延伸ポリプロピレンフイルム、未延伸ポリプロピレンフイルム、延伸ポリアミド樹脂フイルム、無定型ポリエステルフイルム、軟質塩化ビニルフイルム等をドライラミネートすることも可能である。
【０００８】
【実施例】
以下、本発明を実施例により説明する。
実施例１
蓋材として、シール層が非晶性ポリエステル樹脂（ＰＥＴＧ）が３μｍの下記５層の複合フイルムを得た。
▲１▼二軸延伸ポリエステルフイルム層（厚み１６μｍ）//▲２▼エチレン酢酸ビニル共重合ケン化物樹脂層（厚み１０μｍ）／▲３▼ポリアミド樹脂層（厚み２５μｍ）／▲４▼接着性樹脂層（厚み１５μｍ）／▲５▼ＰＥＴＧ層（厚み３μｍ）
ここで、▲２▼〜▲５▼は共押出成形法により得られた複合フイルムであり、▲２▼の外層側に▲１▼をドライラミネートすることで５層の蓋材用複合フイルムを得た。
【０００９】
また、底材としては、シール層がポリカーボネート樹脂の下記５層の複合フイルムを共押出成形法により得た。
ポリカーボネート樹脂層（厚み１５０μｍ）／接着性樹脂層（厚み１５μｍ）／エチレン酢酸ビニル共重合ケン化物樹脂層（厚み２０μｍ）／接着性樹脂層（厚み１５μｍ）／ポリカーボネート樹脂層（厚み１５０μｍ）。
【００１０】
実施例２
蓋材のシール層ＰＥＴＧの厚みを１０μｍに変更した以外は実施例１と同一構成の蓋材および底材用複合フイルムを得た。
【００１１】
実施例３
蓋材は実施例１と同一構成、同一厚みであるが、底材のシール層を直鎖状低密度ポリエチレンとした下記５層の複合フイルムを共押出成形法により得た。
ポリカーボネート樹脂層（厚み２５０μｍ）／接着性樹脂層（厚み１５μｍ）／エチレン酢酸ビニル共重合ケン化物樹脂層（厚み２０μｍ）／接着性樹脂層
（厚み１５μｍ）／直鎖状低密度ポリエチレン層（厚み５０μｍ）。
【００１２】
実施例４
蓋材として、シール層が直鎖状低密度ポリエチレンからなる下記５層の複合フイルムを得た。
▲１▼二軸延伸ポリエステルフイルム層（厚み１６μｍ）//▲２▼エチレン酢酸ビニル共重合ケン化物樹脂層（厚み１０μｍ）／▲３▼ポリアミド樹脂層（厚み２０μｍ）／▲４▼接着性樹脂層（厚み１０μｍ）／▲５▼直鎖状低密度ポリエチレン層（厚み３０μｍ） ここで、▲２▼〜▲５▼は共押出成形法により得られた複合フイルムであり、▲２▼の外層側に▲１▼をドライラミネートすることで５層の蓋材用複合フイルムを得た。
【００１３】
また、底材としては、シール層ＰＥＴＧが５μｍの下記５層の複合フイルムを得た。
▲１▼ポリカーボネート樹脂フイルム層（厚み３００μｍ）//▲２▼エチレン酢酸ビニル共重合ケン化物樹脂層（厚み１０μｍ）／▲３▼ポリアミド樹脂層（厚み２０μｍ）／▲４▼接着性樹脂層（厚み１５μｍ）／▲５▼ＰＥＴＧ層（厚み５μｍ）
ここで、▲２▼〜▲５▼は共押出成形法により得られた複合フイルムであり、▲２▼の外層側に▲１▼をドライラミネートすることで５層の底材用複合フイルムを得た。
【００１４】
比較例１
蓋材のシール層ＰＥＴＧの厚みを１μｍに変更した以外は実施例１と同一構成の蓋材および底材用複合フイルム。
【００１５】
比較例２
蓋材のシール層ＰＥＴＧの厚みを１２μｍに変更した以外は実施例１と同一構成の蓋材および底材用複合フイルム。
【００１６】
比較例３
底材は実施例１と同一構成、同一厚みであるが、蓋材のシール層を直鎖状低密度ポリエチレンとし、隣接する層にはポリプロピレンにエチレン−αオレフィン共重合体を３０重量％ブレンドしたものを配した下記の６層の複合フイルムを得た。
【００１７】
▲１▼二軸延伸ポリエステルフイルム層（厚み１６μｍ）//▲２▼エチレン酢酸ビニル共重合ケン化物樹脂層（厚み１０μｍ）／▲３▼ポリアミド樹脂層（厚み２０μｍ）／▲４▼接着性樹脂層（厚み１０μｍ）／▲５▼ポリプロピレンにエチレンーαオレフィン共重合体を３０重量％ブレンドした層（厚み２０μｍ）
ここで、▲２▼〜▲５▼は共押出成形法により得られた複合フイルムであり、▲２▼の外層側に▲１▼をドライラミネートすることで６層の蓋材用複合フイルムを得た。
【００１８】
［評価試験方法］
前記のように得られた実施例１〜４、及び比較例１〜３の蓋材用複合フイルムと底材用複合フイルムを用い、深絞り包装機（ムルチパック（株）製Ｒ−７０００）により縦１２０ｍｍ×横１６０ｍｍ×深さ２５ｍｍの密封されたパック品を作成し、蓋材を剥離した時の剥離外観、剥離強度（イージーピール強度）を評価した。
【００１９】
（１）剥離外観
蓋材を剥離した後、蓋材のシール部分が膜状に残らず良好なものを（○）、底材側に蓋材のシール部分が膜状に３ｍｍ以上残ったものを（×）とした。
【００２０】
（２）剥離強度（イージーピール強度）
蓋材が剥離される強度を引張試験で測定し、７００〜２０００ｇｆ／１５ｍｍ幅の範囲にあるものを（○）、範囲外のものを（×）とした。
【００２１】
【表１】
【発明の効果】
上述したように、本発明の複合フイルムによれば、シール層が通常のポリオレフィン系樹脂に限定されず、これ以外のポリカーボネート樹脂、熱可塑性ポリエステル樹脂等の高耐熱性樹脂にも優れたヒートシール性を有し、流通過程における包装物の密封性に優れるとともに、開封時には容易に剥離できる耐熱容器用の蓋材や底材に好適に使用できる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a composite film, and in particular, its sealing layer is not limited to ordinary polyolefin-based resins, and has excellent heat-sealing properties for high heat-resistant resins such as polycarbonate resins and thermoplastic polyester resins. The present invention relates to an easily openable composite film that has excellent sealing properties and can be suitably used for a lid or bottom material for heat-resistant containers that can be easily peeled off during use.
[0002]
[Prior art and its problems]
In a gas pack package in which food is filled in a deep-drawn package and filled with an inert gas such as nitrogen gas, a packaging material having both sealing performance and easy opening is required. Conventionally, since an ordinary polyolefin resin is used for the seal layer of an easy-open composite film used for such applications, in heat-resistant containers for microwave ovens, polycarbonate resins and There was a problem that it was difficult to maintain complete sealing with a high heat resistance resin such as a thermoplastic polyester resin.
[0003]
[Means for Solving the Problems]
The present invention has found an easy-open composite film having both a sealing property and an easy-open property that can solve the above-mentioned problems. The gist of the present invention is that the heat seal layer contains ethylene glycol, terephthalic acid, and 1 , 4-cyclohexanedimethanol, the thickness of the heat seal layer is in the range of 2 to 10 μm, and the second layer adjacent to the heat seal layer is a layer made of polyolefin adhesive resin. The third layer adjacent to the second layer is a layer made of a polyamide resin, and peels off at the interface between the heat seal layer and the second layer. .
[0004]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail.
In the present invention, the amorphous polyester provided in the heat seal layer is a copolymer composed of ethylene glycol, terephthalic acid and 1,4-cyclohexanedimethanol. As an example of the amorphous polyester, Eastman Chemical Co., Ltd. PETG6763 (glass transition point 81 degreeC) made from can be used conveniently.
[0005]
Here, the thickness of the heat seal layer needs to be in the range of 2 to 10 μm. If the thickness is less than 2 μm, there is a possibility that the resin melted at the time of heat sealing is divided by the sealing pressure and may not be completely sealed. However, the seal layer does not break at the end of the seal part at the time of peeling, and peeling between layers proceeds to a place other than the seal part, and the sealing layer remains on the peeled surface in the form of a fiber or film.
[0006]
The layer adjacent to the heat seal layer made of the above amorphous polyester resin is usually provided with a polyolefin-based adhesive resin, and the polyolefin-based adhesive resin is at least one monomer selected from unsaturated carboxylic acids or derivatives thereof. The acid-modified polyolefin resin grafted with can be suitably used and peeled off at the interface with the heat seal layer.
[0007]
In addition to the amorphous polyester layer and the adhesive resin layer adjacent to the amorphous polyester layer, the composite film of the present invention can be coextruded with polyamide resin, ethylene vinyl acetate copolymer saponified resin, polyolefin resin, and the like. It is also possible to dry laminate a stretched polyester film, a stretched polypropylene film, an unstretched polypropylene film, a stretched polyamide resin film, an amorphous polyester film, a soft vinyl chloride film, etc. on the opposite surface of the sealing layer of the composite film. .
[0008]
【Example】
Hereinafter, the present invention will be described with reference to examples.
Example 1
As a cover material, the following five layers of composite films having a sealing layer of 3 μm of amorphous polyester resin (PETG) were obtained.
(1) Biaxially stretched polyester film layer (thickness 16 μm) // (2) Ethylene vinyl acetate copolymer saponified resin layer (thickness 10 μm) / (3) Polyamide resin layer (thickness 25 μm) / (4) Adhesive resin layer (Thickness 15 μm) / (5) PETG layer (Thickness 3 μm)
Here, (2) to (5) are composite films obtained by the co-extrusion molding method, and five layers of the composite film for lid materials are obtained by dry laminating (1) on the outer layer side of (2). It was.
[0009]
Further, as a bottom material, a composite film having the following five layers whose sealing layer is a polycarbonate resin was obtained by a coextrusion molding method.
Polycarbonate resin layer (thickness 150 μm) / adhesive resin layer (thickness 15 μm) / ethylene vinyl acetate copolymer saponified resin layer (thickness 20 μm) / adhesive resin layer (thickness 15 μm) / polycarbonate resin layer (thickness 150 μm).
[0010]
Example 2
A cover material and a composite film for a bottom material having the same configuration as in Example 1 were obtained except that the thickness of the seal layer PETG of the cover material was changed to 10 μm.
[0011]
Example 3
The lid material had the same configuration and the same thickness as in Example 1, but a composite film of the following 5 layers in which the bottom seal layer was a linear low density polyethylene was obtained by a coextrusion molding method.
Polycarbonate resin layer (thickness 250 μm) / adhesive resin layer (thickness 15 μm) / ethylene vinyl acetate copolymer saponified resin layer (thickness 20 μm) / adhesive resin layer (thickness 15 μm) / linear low density polyethylene layer (thickness 50 μm) ).
[0012]
Example 4
As a cover material, the following five-layer composite film in which the seal layer was made of linear low density polyethylene was obtained.
(1) Biaxially stretched polyester film layer (thickness 16 μm) // (2) Ethylene vinyl acetate copolymer saponified resin layer (thickness 10 μm) / (3) Polyamide resin layer (thickness 20 μm) / (4) Adhesive resin layer (Thickness 10 μm) / (5) Linear low-density polyethylene layer (thickness 30 μm) Here, (2) to (5) are composite films obtained by the coextrusion molding method, and on the outer layer side of (2) (1) was dry laminated to obtain a 5-layer composite film for a lid material.
[0013]
Moreover, as a bottom material, the following five layers of composite films having a seal layer PETG of 5 μm were obtained.
(1) Polycarbonate resin film layer (thickness 300 μm) // (2) Ethylene vinyl acetate copolymer saponified resin layer (thickness 10 μm) / (3) Polyamide resin layer (thickness 20 μm) / (4) Adhesive resin layer (thickness) 15μm) / (5) PETG layer (thickness 5μm)
Here, (2) to (5) are composite films obtained by the co-extrusion molding method, and five layers of composite films for the bottom material are obtained by dry laminating (1) on the outer layer side of (2). It was.
[0014]
Comparative Example 1
A lid material and bottom material composite film having the same configuration as in Example 1 except that the thickness of the lid seal layer PETG was changed to 1 μm.
[0015]
Comparative Example 2
A lid material and bottom material composite film having the same configuration as in Example 1 except that the thickness of the lid seal layer PETG was changed to 12 μm.
[0016]
Comparative Example 3
The bottom material has the same configuration and the same thickness as in Example 1, but the sealing layer of the lid is made of linear low density polyethylene, and the adjacent layer is blended with polypropylene by 30% by weight of ethylene-α olefin copolymer. The following 6-layer composite film was obtained.
[0017]
(1) Biaxially stretched polyester film layer (thickness 16 μm) // (2) Ethylene vinyl acetate copolymer saponified resin layer (thickness 10 μm) / (3) Polyamide resin layer (thickness 20 μm) / (4) Adhesive resin layer (Thickness 10 μm) / (5) Layer in which 30% by weight of ethylene-α-olefin copolymer is blended with polypropylene (thickness 20 μm)
Here, (2) to (5) are composite films obtained by the co-extrusion molding method, and 6 layers of composite films for lid materials are obtained by dry laminating (1) on the outer layer side of (2). It was.
[0018]
[Evaluation test method]
Using the composite film for lids and the composite film for bottom materials of Examples 1 to 4 and Comparative Examples 1 to 3 obtained as described above, using a deep drawing packaging machine (R-7000 manufactured by Multipack Co., Ltd.). A sealed pack product having a length of 120 mm, a width of 160 mm, and a depth of 25 mm was prepared, and the peel appearance and peel strength (easy peel strength) when the lid member was peeled were evaluated.
[0019]
(1) Peeling appearance After peeling off the lid material, the sealing part of the lid material is not left in the form of a film (○), and the sealing part of the lid material on the bottom material side is left in a film shape of 3 mm or more. (X).
[0020]
(2) Peel strength (easy peel strength)
The strength at which the lid material was peeled was measured by a tensile test, and the one in the range of 700 to 2000 gf / 15 mm width was (◯), and the one out of the range was (x).
[0021]
[Table 1]
【The invention's effect】
As described above, according to the composite film of the present invention, the sealing layer is not limited to ordinary polyolefin resin, and heat sealability excellent also in other high heat resistance resins such as polycarbonate resin and thermoplastic polyester resin. It has excellent sealing properties of the package in the distribution process, and can be suitably used for a lid material or a bottom material for a heat-resistant container that can be easily peeled when opened.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23316997A JP3780075B2 (en) | 1997-08-29 | 1997-08-29 | Easy-open composite film for heat-resistant containers |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23316997A JP3780075B2 (en) | 1997-08-29 | 1997-08-29 | Easy-open composite film for heat-resistant containers |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH1170626A JPH1170626A (en) | 1999-03-16 |
| JP3780075B2 true JP3780075B2 (en) | 2006-05-31 |
Family
ID=16950816
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23316997A Expired - Lifetime JP3780075B2 (en) | 1997-08-29 | 1997-08-29 | Easy-open composite film for heat-resistant containers |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3780075B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4806843B2 (en) * | 2000-11-24 | 2011-11-02 | 住友化学株式会社 | Easy peelable film |
-
1997
- 1997-08-29 JP JP23316997A patent/JP3780075B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH1170626A (en) | 1999-03-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5888648A (en) | Multi-layer hermetically sealable film and method of making same | |
| JPH0327938A (en) | Non-orientation polyester film for lid material with modified heat-seal layer | |
| JP5394096B2 (en) | Easy peel film | |
| GB2360038A (en) | Heat sealable polymeric films | |
| USH1727H (en) | Heat sealable packaging materials having a peelable, easy-opening feature | |
| JP4270621B2 (en) | Retort injection molded container | |
| AU2021200176A1 (en) | Oven skin packaging film | |
| JP2724938B2 (en) | Easy peel coextruded laminated film | |
| JP2007076281A (en) | Laminated packaging material and packaging bag using it | |
| JP3780075B2 (en) | Easy-open composite film for heat-resistant containers | |
| AU722202B2 (en) | Peelable heat seals and method for making same | |
| JPH0494933A (en) | Peelable film | |
| JP2003145699A (en) | Coextrusion composite film for deep draw packaging, and deep draw package | |
| JP3957996B2 (en) | Deep drawn package | |
| JP3795205B2 (en) | Easy-open composite film | |
| JP2968425B2 (en) | Composite multilayer film | |
| JP2611006B2 (en) | Coextruded film with easily peelable sealant | |
| JPS6327254A (en) | Easy-open package | |
| JP3124206B2 (en) | Laminate | |
| JPH061368A (en) | Lid member made of plastic | |
| JPH07137216A (en) | Easily openable film | |
| JP3706153B2 (en) | Easy peelable film for food packaging | |
| JPH10264330A (en) | Easily tearable coextrusion composite film | |
| JPH05338099A (en) | Cover material made of plastic | |
| JPH09234815A (en) | Laminate for easily tearable sealant and packaging bag and cover material using the laminate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20050704 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20050719 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20050912 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20060207 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20060306 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090310 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100310 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100310 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110310 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130310 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130310 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140310 Year of fee payment: 8 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| EXPY | Cancellation because of completion of term |