JP2006051673A - Film for deep drawing, bottom material for deep-drawn package, and deep-drawn package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film for deep drawing which keeps glossiness without making a bottom material outer layer be adhered to the rubber packing of a seal box by heat-sealing heat. <P>SOLUTION: The film has at least an amorphous polyester resin layer and an easily peelable layer which has a cohesive failure property and can be heat-sealed at 115°C or below. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention mainly relates to a film that can be suitably used for packaging sliced ham, sliced bacon, and the like, a bottom material for a deep drawn package, and a deep drawn package.

  Sliced ham, sliced bacon and the like are usually distributed and sold in a deep-drawn package. As shown in FIG. 1, such a deep drawn package is obtained by joining a bottom material 20 having a cylindrical recess 60 at a substantially central portion and a lid material 10 by heat sealing or the like. Sliced ham or the like is accommodated in the recess 60.

Conventionally, as the bottom material 20 for a deep-drawn package, a multilayer film having PETG as an outer layer, Ny and EVOH as an intermediate layer, and an easy peel layer of a cohesive failure type as a seal layer has been widely used. (For example, patent document 1). The reason is that the deep-drawn package having this configuration has a good film waist, is excellent in gloss and transparency, and has a very good appearance. However, PETG used in the outer layer does not have a melting point and has a property of softening when the glass transition point (Tg) of about 80 ° C. is exceeded. Therefore, for example, as shown in FIG. 2, the outer surface of the lid member 10 is closely attached to the hot plate 30, the seal box 50 is raised from the bottom 20 side, and the rubber packing 40 and the hot plate 30 on the upper surface of the seal box 50 are In a sealing process in which a film is sandwiched between and heat sealing at a temperature of 125 ° C. or higher, the PETG surface of the outer layer of the bottom material 20 adheres to the rubber packing 40 of the sealing box 50 due to the sealing heat, and the PETG of the heat sealing portion There was a problem that the glossiness of the surface deteriorated.
JP 2001-253028 A

  The present invention is intended to solve the above-mentioned problems of the prior art, and an object of the present invention is to prevent the bottom layer outer layer from adhering to the rubber packing of the seal box and to reduce the glossiness by heat sealing heat. An object of the present invention is to provide a film for deep drawing.

  Another object of the present invention is to provide a bottom material for a deep-drawn package and a deep-drawn package comprising the deep-drawing film of the present invention.

  The object of the present invention is achieved by the following deep drawing film.

  1st this invention is a film for deep drawing characterized by having an amorphous polyester resin layer and the easy peel layer which can be heat-sealed at 115 degrees C or less, and has cohesive failure. .

  Here, having a cohesive fracture property means that when the deep-drawn package is opened, the easy peel layer itself is broken and peeled off, and the easy peel layer after the break is the upper layer side (bottom material side) of the easy peel layer And remaining on both the lower layer side (lid side).

  The amorphous polyester resin is preferably a polyethylene terephthalate glycol resin (PETG).

The easy peel layer is preferably composed of 40 to 80% by mass of resin A and 20 to 60% by mass of resin B shown below based on the mass of the entire easy peel layer (100% by mass). .
Resin A: linear low density polyethylene (LLDPE) having a Vicat softening point of 90 ° C. or lower, ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower, ethylene-acrylic acid copolymer (EAA), ethylene-acrylic Ethyl acid copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-methyl acrylate copolymer (EMA), and a group consisting of these ionomers Resin B: Polypropylene (PP) or polybutylene (PB)

  It is preferable to have at least one polyamide resin (PA) layer between the amorphous polyester resin layer and the easy peel layer.

  It is preferable that at least one ethylene-vinyl acetate copolymer saponified product (EVOH) layer is provided between the amorphous polyester resin layer and the easy peel layer.

  It is preferable that at least one ethylene-vinyl acetate copolymer layer or polyethylene layer is provided between the amorphous polyester resin layer and the easy peel layer.

  It is preferable to have at least one adhesive resin layer between the amorphous polyester resin layer and the easy peel layer.

  The easy peel strength of the easy peel layer is preferably 0.8 to 5 N / 15 mm at 25 ° C.

  The second aspect of the present invention is a bottom material for a deep drawn package formed by the deep drawing film described above.

  The third aspect of the present invention is a deep drawn package using the above bottom material.

  The deep drawing film of the present invention has at least an outer layer made of an amorphous polyester resin and an easy peel layer that can be heat-sealed at a temperature of 115 ° C. or less and has cohesive failure. With this configuration, according to the present invention, since the outermost layer does not adhere to the rubber packing of the seal box at the time of heat sealing, it is possible to obtain an optimum film for deep drawing having good gloss and finish. it can.

  Since the film of the present invention is a film having good gloss and finish, it can be suitably used as a film for a deep drawn package, particularly as a bottom material for a deep drawn package.

  Hereinafter, the film for deep drawing, the bottom material for a deep drawing package, and the deep drawing package of the present invention will be described in more detail.

[Film for deep drawing]
The film of the present invention has at least an amorphous polyester resin layer as an outermost layer and an easy peel layer that can be heat-sealed at a temperature of 115 ° C. or less as an innermost layer and has cohesive failure. Here, the “outermost layer” refers to a layer that contacts the rubber packing 40 during heat sealing with the lid member 10 in the bottom member 20, and the “innermost layer” refers to a layer that contacts the lid member 10 in the bottom member 20. Say.

<Amorphous polyester resin layer>
The “amorphous polyester resin” constituting the outermost layer of the film of the present invention refers to a polyester resin in which 5 mol% or more of 1,4-cyclohexanedimethanol component is contained in 100 mol% of a polyhydric alcohol component. From the viewpoint of increasing the degree of amorphousness, it is desirable that the 1,4-cyclohexanedimethanol component is contained in an amount of 10 mol% or more, preferably 12 mol% or more, more preferably 15 mol% or more. On the other hand, if the 1,4-cyclohexanedimethanol component is too much, the impact strength of the film will decrease, so the upper limit is preferably 50 mol%, more preferably 47 mol% or less, and 45 mol. % Or less is more preferable.

  In the film of the present invention, in consideration of tear resistance, impact strength, heat resistance, etc., the ethylene terephthalate unit is 50 mol% or more, preferably 55 mol% or more in 100 mol% of the unit constituting the amorphous polyester resin. Further, it is preferable to select so as to be 60 mol% or more. Therefore, 50 mol% or more of the terephthalic acid component (component formed from terephthalic acid or its ester) in 100 mol% of the polyvalent carboxylic acid component, and 50 to 95 mol of ethylene glycol component in 100 mol% of the polyhydric alcohol component %, Preferably 55 to 90 mol%, more preferably 60 to 88 mol%.

  Examples of the polyhydric alcohol for forming the polyhydric alcohol component include 1,3-propanediol, triethylene glycol, 1,4-butanediol in addition to the above-mentioned 1,4-cyclohexanedimethanol and ethylene glycol. 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 2-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 1,9 -Alkylene glycols such as nonanediol, 1,10-decanediol, trimethylolpropane, glycerin, pentaerythritol, diethylene glycol, dimer diol, polyoxytetramethylene glycol, polyethylene glycol, bisphenol compounds or their derivatives Ido adducts such as can also be used in combination.

  In addition to the above-mentioned terephthalic acid and its esters, aromatic dicarboxylic acids, their ester-forming derivatives, aliphatic dicarboxylic acids, etc. can be used as the polyvalent carboxylic acids for forming the polyvalent carboxylic acid component. is there. Examples of the aromatic dicarboxylic acid include isophthalic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, and 5-sodium sulfoisophthalic acid. Moreover, derivatives of these aromatic dicarboxylic acids and terephthalic acids include derivatives such as dialkyl esters and diaryl esters. Examples of the aliphatic dicarboxylic acid include glutaric acid, adipic acid, sebacic acid, azelaic acid, oxalic acid, succinic acid and the like, and an aliphatic dicarboxylic acid usually called dimer acid. Furthermore, an oxycarboxylic acid such as p-oxybenzoic acid, and a polyvalent carboxylic acid such as trimellitic anhydride and pyromellitic anhydride may be used in combination as necessary.

  In addition, although not polyhydric alcohols or polycarboxylic acids, lactones represented by ε-caprolactone may be used in part. Lactones are those that ring-open to become units having ester bonds at both ends, and a unit derived from one lactone can be considered to be a carboxylic acid component and an alcohol component. Therefore, when using lactones, the amount of 1,4-cyclohexanedimethanol component and the amount of other polyhydric alcohol components are the total amount of polyhydric alcohol components of the film plus the unit amount derived from lactones. Calculated as 100 mol%. Also, when calculating the amount of each polycarboxylic acid component, the amount obtained by adding the unit amount derived from the lactone to the total polyvalent carboxylic acid component amount of the film is 100 mol%.

  For example, a polyethylene terephthalate glycol resin (PETG) in which the diol component is composed of 1,4-cyclohexanedimethyl alcohol and ethylene glycol and the dicarboxylic acid component is composed of terephthalic acid can be suitably used as the amorphous polyester resin of the present invention.

  Although the thickness of an amorphous polyester resin layer is not specifically limited, It is preferable that it is the range of 10-50 micrometers, It is more preferable that it is 15-40 micrometers, It is further more preferable that it is 20-35 micrometers. When the thickness is less than 10 μm, curling occurs in the flange portion of the package, so that the appearance deteriorates. When the thickness exceeds 50 μm, the film becomes hard and the deep drawability deteriorates.

<Easy peel layer>
The film of the present invention has an easy peel layer that can be heat-sealed at a temperature of 115 ° C. or lower as an innermost layer and has cohesive failure. In the easy peel layer, a resin having a heat seal temperature of 115 ° C. or lower can be suitably used. If the heat seal temperature is 115 ° C. or lower, the PETG of the outer layer adheres to the rubber packing of the deep drawing packaging machine seal part box during the heat sealing by the deep drawing packaging machine and prevents the gloss from being lowered. be able to.

  The resin constituting the easy peel layer is not particularly limited as long as it can be heat-sealed at a temperature of 115 ° C. or less and has a cohesive fracture property. An easy peel layer can be comprised from the following resin A and resin B from which a kind differs, for example. That is, as the resin A, the main component is a linear low density polyethylene (LLDPE) having a Vicat softening point of 90 ° C. or lower, an ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower, and an ethylene-acrylic acid copolymer. (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-methyl acrylate copolymer (EMA) And at least one selected from the group consisting of these ionomers can be used, and in particular, an ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower can be suitably used. On the other hand, as the resin B, polypropylene (PP) or polybutylene (PB) can be used. As the PP of the resin B, any of a random copolymer, a homopolymer, a block copolymer and the like can be used, and among these, a random copolymer can be preferably used.

  The resin A and resin B contents are 40 to 80% by mass, preferably 50 to 75% by mass, and more preferably 50 to 75% by mass with respect to the mass of the entire easy peel layer from the viewpoints of sealing properties and unsealing properties. It is desirable that the content is 60% by mass, and the resin B is 20 to 60% by mass, preferably 25 to 50% by mass, and more preferably 40 to 50% by mass. By setting the content of the resin A to 40% by mass or more (that is, the content of the resin B is 60% by mass or less), good heat sealability can be maintained. On the other hand, when the content of the resin A is 80% by mass or less (that is, the content of the resin B is 20% by mass or more), an appropriate easy peel strength can be obtained, and a good opening property can be obtained.

  The thickness of the easy peel layer is desirably 3 to 15 μm, preferably 4 to 12 μm, and more preferably 5 to 10 μm from the viewpoint of film forming property and peel appearance. By setting the thickness of the easy peel layer to 3 μm or more, stable film forming properties can be obtained. On the other hand, by setting the thickness of the easy peel layer to 15 μm or less, it is possible to prevent the occurrence of fuzz and film residue at the time of peeling, and a good peeling appearance can be obtained.

  The easy peel strength of the easy peel layer is preferably 0.8 to 5 N / 15 mm and particularly preferably 1 to 3 N / 15 mm at 25 ° C. from the viewpoint of the balance between easy opening and sealing properties. .

<Intermediate layer>
The film of this invention can provide an intermediate | middle layer between an amorphous polyester resin layer and an easy peel layer. Here, the intermediate layer refers to a single layer or a layer composed of two or more layers provided between the amorphous polyester resin layer and the easy peel layer. Below, each layer which comprises an intermediate | middle layer is demonstrated.

(PA layer)
As the intermediate layer, at least one polyamide resin (PA) layer can be provided for the purpose of imparting pinhole resistance and deep drawability.

  PA used in the intermediate layer is not particularly limited, but nylon-based resin (Ny) is preferably used from the viewpoint of pinhole resistance. Examples of Ny include polymers of condensed units such as 6 nylon, 66 nylon, 69 nylon, 6-66 nylon, 12 nylon, 11 nylon, 610 nylon, 612 nylon, 6I-6T nylon, and MXD6 nylon, or two of these. Copolymers with the above, and mixtures thereof can also be mentioned. Among them, it is preferable to use 6 nylon or 6-66 nylon.

  When a PA layer is provided as the intermediate layer, the thickness of the PA layer is 2 to 30 μm, preferably 3 to 20 μm, and more preferably 5 to 15 μm. By setting the lower limit of the thickness of the PA layer to 2 μm, good pinhole resistance can be obtained, and by setting the upper limit to 30 μm, the cutability and thermoformability of the film can be maintained well.

(EVOH layer)
As the intermediate layer, an EVOH layer can be provided for the purpose of imparting oxygen barrier properties. Although the ethylene content of EVOH used in the EVOH layer is not particularly limited, it is preferably 32 to 47 mol%, more preferably 38 to 44 mol% from the viewpoint of film formation stability. Further, EVOH has a saponification degree of 90% or more, preferably 95 mol% or more. By maintaining the ethylene content of EVOH and the saponification degree within the above ranges, the coextrudability of the film of the present invention and the strength of the film can be improved.

  When providing an EVOH layer, the thickness of the EVOH layer is 5 to 30 μm, preferably 8 to 25 μm, and more preferably 10 to 20 μm. By setting the lower limit of the EVOH layer thickness to 5 μm, sufficient oxygen barrier properties can be obtained, and by setting the upper limit to 30 μm, the coextrudability of the film is not deteriorated and good film strength is maintained. it can.

(EVA layer and PE layer)
Further, as the intermediate layer, an ethylene-vinyl acetate copolymer (EVA) layer or a polyethylene (PE) layer can be provided for the purpose of imparting flexibility. The ethylene content of EVA is not particularly limited, but is preferably 32 to 47 mol%, more preferably 38 to 44 mol% from the viewpoint of film formation stability. When the EVA layer is provided, the thickness of the EVA layer is 10 to 100 μm, preferably 20 to 80 μm, and more preferably 25 to 60 μm from the viewpoint of film formability.

  When providing an intermediate layer with a PE layer, the PE used in the PE layer is not particularly limited. For example, low density polyethylene (LDPE), high density polyethylene (HDPE), or a blend of LDPE and HDPE is used. can do. The blend ratio can be appropriately determined for the purpose of imparting desired flexibility. For example, the blending ratio of LDPE and HDPE is 40 to 80:60 to 20, preferably 50 to 80:50 to 20, more preferably by mass ratio. Preferably it can be set to 60-80: 40-20.

  LDPE having a density of 0.92 or more is preferable, and HDPE having a density of 0.95 or more is preferably used. By using a high-density material, moderate hardness can be imparted to the PE layer while maintaining flexibility. The thickness of the PE layer is 10 to 100 μm, preferably 20 to 80 μm, and more preferably 25 to 60 μm.

(Adhesive resin layer)
Further, in the intermediate layer, an adhesive resin layer can be provided for bonding the layers. The adhesive resin used in the adhesive resin layer is not particularly limited as long as it can adhere the EVOH layer, PA layer, PE layer, and amorphous polyester layer to the required strength, but is modified with an unsaturated carboxylic acid or derivative thereof. Polyolefin resin can be used preferably. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid and the like. In addition, an ester or anhydride of the unsaturated carboxylic acid can be used as an adhesive resin, and as derivatives, methyl acrylate, methyl methacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, butyl methacrylate, vinyl acetate. , Glycidyl acrylate, glycidyl methacrylate, acrylamide, methacrylamide, sodium acrylate and the like can be used. Moreover, as a commercially available adhesive resin, Mitsui Chemicals, Inc. make and brand name Admer are mentioned, for example, These can be used conveniently. In particular, when a PE layer, an EVOH layer, and an amorphous polyester layer are bonded, a special polyolefin base (polyolefin resin modified with the above unsaturated carboxylic acid or the like) is useful. Furthermore, the EVOH layer and PE When the layers are bonded, those of LLDPE type can be preferably used.

  At least one adhesive resin layer can be provided between the amorphous polyester resin layer and the intermediate layer. Furthermore, from the viewpoint of further increasing the interlayer adhesive strength, it is preferable to provide the intermediate layer between the EVOH layer and the EVA layer, or between the PA layer, the EVOH layer, and the EVA layer.

<Layer structure>
The layer structure of the film of the present invention is not particularly limited as long as an amorphous polyester resin layer is disposed as the outermost layer and an easy peel layer is disposed as the innermost layer. For example, the amorphous polyester resin layer (A), PA layer (B), EVOH layer (C), EVA layer (D), PE layer (E), easy peel layer (F) and adhesive resin layer (G) When expressed, the following layer structure can be formed. Among these, a preferable layer configuration is the following (1), (3), (5) or (7), and a more preferable layer configuration is (1) or (5).

(1) A / G / B / C / G / D / F
(2) A / G / B / G / C / G / D / F
(3) A / G / B / C / G / E / F
(4) A / G / B / G / C / G / E / F
(5) A / G / C / B / G / D / F
(6) A / G / C / G / B / G / D / F
(7) A / G / C / B / G / E / F
(8) A / G / C / B / G / G / E / F
(9) A / G / D / F
(10) A / G / E / F
(11) A / G / B / G / D / F
(12) A / G / B / G / E / F
(13) A / G / C / G / D / F
(14) A / G / C / G / E / F

<Manufacturing method>
The film of the present invention can be produced by simultaneously or sequentially laminating an amorphous polyester resin layer, an easy peel layer, and an intermediate layer formed therebetween.

  The film of the present invention is obtained by co-extrusion using an extruder equipped with a die by an existing method such as a T-die method, a water-cooled or air-cooled inflation method, a tubular method, and the like. An intermediate layer can be produced simultaneously (coextrusion method). The film can also be produced sequentially by forming the resin constituting each layer separately and then laminating them using a press method or a roll nip method. The film of the present invention can be preferably produced by the former method.

[Bottom material for deep-drawn packaging and deep-drawn packaging]
The film of the present invention can be formed into a deep-drawing package bottom material having a size and shape corresponding to the contents using a deep-drawing packaging machine. In particular, when the film of the present invention is used as a bottom material of a deep drawn package, a deep drawn package excellent in gloss can be obtained. When used as a bottom material for a deep-drawn package, for example, after forming the film of the present invention into a desired shape and size with a deep-drawing mold (film supply step and film forming step), Fill the contents (content filling process), seal with a lid material film from above (cover material film supply process and sealing process), vacuum package (vacuum packaging process), cool (cooling process), By cutting (cutting step), a deep drawn package can be produced.

  The lid of the deep drawn package of the present invention is not particularly limited as long as the easy peel property of the film of the present invention can be obtained. For example, a cover material obtained by laminating a stretched polypropylene resin layer, a transparent vapor-deposited polyethylene terephthalate resin, and a linear low-density polyethylene (LLDPE) layer, or a stretched polyethylene terephthalate resin and a coextruded film (EVOH, Ny, including LLDPE as a seal layer) Can be mentioned.

  The package of the present invention can be produced by adhering the above-mentioned lid material and the bottom material of the present invention by an adhesive means such as heat sealing.

  Examples of the present invention will be described below, but the present invention is not limited thereto.

Example 1
A film having the following layer constitution was obtained by co-extrusion of all layers, and Example 1 was obtained.
PETG (20 μm) / Adhesive resin (10 μm) / Ny (10 μm) / EVOH (15 μm) / Adhesive resin (10 μm) / EVA1 (28 μm) / EP1 (7 μm)
PETG: PETG manufactured by Eastman Chemical Company
Adhesive resin: Mitsui Chemicals Admer Ny: Mitsubishi Engineering Plastic Novamid 66 Ny 6-66 copolymer Ny with 15% ratio
EVOH: Kuraray Eval 44 mol type EVA1: Nippon Polyethylene Novatec EVA (VAC 6%)
EP1: Blend of LLDPE (60%) and polybutene (40%) having a Vicat softening point of 85 ° C. LLDPE: Moretec Polybutene made by Idemitsu Petrochemicals: Tuffmer made by Mitsui Chemicals

(Example 2)
A film having the following layer constitution was obtained by coextrusion of all layers, and was designated as Example 2.
PETG (30 μm) / Adhesive resin (10 μm) / Ny (5 μm) / EVOH (15 μm) / Adhesive resin (10 μm) / EVA1 (23 μm) / EP2 (7 μm)
PETG: PETG manufactured by Eastman Chemical Company
Adhesive resin: Mitsui Chemicals Admer Ny: Mitsubishi Engineering Plastic Novamid 66 Ny 6-66 copolymer Ny with 15% ratio
EVOH: Kuraray Eval 44 mol type EVA1: Nippon Polyethylene Novatec EVA (VAC 6%)
EP2: Blend of EVA2 (60%) with a melting point of 97 ° C. and random copolymer PP (40%) EVA2: Novatec EVA made by Nippon Polyethylene (VAC 15%)
Random copolymer PP: Novatec PP made by Nippon Polypro

(Comparative Example 1)
A film having the following layer structure was obtained by coextrusion of all layers, and was designated as Comparative Example 1.
PETG (20 μm) / Adhesive resin (10 μm) / Ny (10 μm) / EVOH (15 μm) / Adhesive resin (10 μm) / EVA1 (28 μm) / EP3 (7 μm)
PETG: PETG manufactured by Eastman Chemical Company
Adhesive resin: Mitsui Chemicals Admer Ny: Mitsubishi Engineering Plastic Novamid 66 Ny 6-66 copolymer Ny with 15% ratio
EVOH: Kuraray Eval 44 mol type EVA1: Nippon Polyethylene Novatec EVA (VAC 6%)
EP3: Blend of LLDPE (60%) and polybutene (40%) having a Vicat softening point of 105 ° C. LLDPE: Moretec Polybutene made by Idemitsu Petrochemical Co., Ltd. Toughmer made by Mitsui Chemicals

(Comparative Example 2)
A film having the following layer structure was obtained by coextrusion of all layers, and was designated as Comparative Example 2.
PETG (20 μm) / Adhesive resin (10 μm) / Ny (10 μm) / EVOH (15 μm) / Adhesive resin (10 μm) / EVA1 (28 μm) / EP4 (7 μm)
PETG: PETG manufactured by Eastman Chemical Company
Adhesive resin: Mitsui Chemicals Admer Ny: Mitsubishi Engineering Plastic Novamid 66 Ny 6-66 copolymer Ny with 15% ratio
EVOH: Kuraray Eval 44 mol type EVA1: Nippon Polyethylene Novatec EVA (VAC 6%)
EP4: BLD LLDPE with a Vicat softening point of 97 ° C and LLDPE (85%) and polybutene (15%): Idemitsu Petrochemical's MORETECH Polybutene: Mitsui Chemicals Toughmer

(Comparative Example 3)
A film having the following layer structure was obtained by coextrusion of all layers, and was designated as Comparative Example 3.
PETG (20 μm) / Adhesive resin (10 μm) / Ny (10 μm) / EVOH (15 μm) / Adhesive resin (10 μm) / EVA1 (28 μm) / EP5 (7 μm)
PETG: PETG manufactured by Eastman Chemical Company
Adhesive resin: Mitsui Chemicals Admer Ny: Mitsubishi Engineering Plastic Novamid 66 Ny 6-66 copolymer Ny with 15% ratio
EVOH: Kuraray Eval 44 mol type EVA1: Nippon Polyethylene Novatec EVA (VAC 6%)
EP5: Blend of LLDPE (35%) and polybutene (75%) with a Vicat softening point of 97 ° C. LLDPE: Moretech Polybutene made by Idemitsu Petrochemicals: Tuffmer made by Mitsui Chemicals

[Preparation of packed sample]
Slice ham (50 g) was vacuum-packed with a deep-drawing packaging machine (FV6300 manufactured by Omori Machine Industry Co., Ltd.). In addition, the used lid | cover material was produced by the dry lamination method with the following structure.
OPP (30 μm) // Transparent deposition PET (12 μm) // LLDPE (40 μm)
OPP: OPU-1 (biaxially stretched by Tosero)
Transparent deposition PET: VM-PET (Toyo Metallizing deposition PET)
LLDPE: L-6102 (Toyobo)

[Evaluation methods]
<Minimum heat seal temperature>
In the deep-drawing packaging machine, the temperature at which the heat sealing is sufficiently performed at the sealing time of 2 seconds was defined as the minimum heat sealing temperature.
<Bottom material PETG chamfer>
After heat-sealing, the bottom material PETG was taken on the rubber packing, and the case where whitening could be confirmed was evaluated as x, and the case where it was not confirmed as ◯.
<Easy peel strength>
The seal portion of the packed product was cut into a strip shape having a width of 15 mm with respect to the film flow direction, and the maximum load when the lid material and the bottom material were peeled off at a speed of 200 mm / min with a tensile tester was defined as easy peel strength.
<Exfoliation appearance>
When the pack product was peeled by hand, the case where there was no fluffing and film residue on the peeled surface was indicated as ◯, and the case where there was a mark as x.

  Since Examples 1 and 2 were heat-sealable at 110 ° C., the PETG surface was not taken by the rubber packing, the easy peel strength was good for easy opening, and the peel appearance was also good.

  On the other hand, in Comparative Example 1, the heat seal temperature exceeded 115 ° C., and the PETG surface was whitened by the rubber packing. In Comparative Example 2, the easy peel strength was too strong and the openability was poor. Further, since Comparative Example 3 has poor heat sealability, the easy peel strength is weak, and there is a risk of bag breakage during transportation. Further, no increase in easy peel strength was observed even when the seal temperature was raised.

It is explanatory drawing which shows the package body before joining. It is explanatory drawing which shows the sealing process of a cover material and a bottom material.

Explanation of symbols

10 Lid material 20 Bottom material 30 Hot plate 40 Rubber packing 50 Seal box 60 Recess

Claims (10)

  A film for deep drawing, comprising at least an amorphous polyester resin layer and an easy peel layer capable of heat sealing at 115 ° C. or less and having cohesive failure.   The film for deep drawing according to claim 1, wherein the amorphous polyester resin is a polyethylene terephthalate glycol resin (PETG). The said easy peel layer is comprised from 40-80 mass% resin A and 20-60 mass% resin B which are shown below on the basis (100 mass%) of the mass of the whole easy peel layer. Or the film for deep drawing of 2.
Resin A: linear low density polyethylene (LLDPE) having a Vicat softening point of 90 ° C. or lower, ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower, ethylene-acrylic acid copolymer (EAA), ethylene-acrylic Ethyl acid copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-methyl acrylate copolymer (EMA), and a group consisting of these ionomers Resin B: Polypropylene (PP) or polybutylene (PB)   The film for deep drawing according to any one of claims 1 to 3, further comprising at least one polyamide resin (PA) layer between the amorphous polyester resin layer and the easy peel layer.   The depth according to any one of claims 1 to 4, further comprising at least one ethylene-vinyl acetate copolymer saponified product (EVOH) layer between the amorphous polyester resin layer and the easy peel layer. Drawing film.   The deep-drawing molding according to any one of claims 1 to 5, wherein at least one ethylene-vinyl acetate copolymer layer or polyethylene layer is provided between the amorphous polyester resin layer and the easy peel layer. Film.   The film for deep drawing according to any one of claims 1 to 6, further comprising at least one adhesive resin layer between the amorphous polyester resin layer and the easy peel layer.   The deep-peeling film according to any one of claims 1 to 7, wherein an easy peel strength of the easy peel layer is 0.8 to 5 N / 15 mm at 25C.   A bottom material for a deep drawn package formed by the deep drawn film according to any one of claims 1 to 8. A deep-drawn package using the bottom material according to claim 9.

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