JP2014184971A - Resealable package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package excellent in food hygiene, and having excellent opening properties, excellent resealing properties only by crimping with the finger, and a mischief/alteration preventing function.SOLUTION: A package is such that in a multilayer film in which a surface resin layer 3, an adhesive resin layer 4, a peeling resin layer 5, and a heat seal resin layer 6 are stacked in this order, the layer has as the main component, styrenic thermoplastic elastomer having a temperature showing a peak value of loss tangent (tanδ) of equal to or more than -35°C, the layer 5 has as the lid material or bottom material, a multilayer film with a resealable function, comprising a layer formed of cyclic olefin resin of a glass-transition temperature (Tg) of 100-150°C, and the bottom material and the lid material are heat-sealed by heat sealing the heat seal resin layer 6 of the multilayer film to a heat seal part of a body to be sealed. Furthermore, in the resealable package, when the layer 4 and the layer 5 are separated between the layers in the heat seal part, both layers expose in a resealable state.

Description

  TECHNICAL FIELD The present invention relates to a multilayer film, and more particularly to a multilayer film with a reseal function suitably used for packaging foods and pharmaceuticals, and a resealable package using the same.

  Conventionally, various packages with resealing function have been used as packaging means for cosmetics and sanitary products that are repeatedly opened and resealed every time they are used, or for food and pharmaceuticals that cannot be consumed once. . This package can prevent oxidative deterioration of the contents remaining after opening, or deterioration due to moisture absorption, drying, etc. For example, a zipper type package in which a plastic zipper is laminated is known. However, although this package can be repeatedly opened and has excellent durability, a dedicated device for attaching an accessory such as a zipper to the package is necessary, and a processing step associated therewith is also necessary. There are problems such as increased manufacturing costs and reduced production efficiency.

  On the other hand, a multilayer film that can give a reseal function to the package itself without attaching an accessory such as a zipper has been developed. For example, Patent Documents 1 and 2 include a surface resin layer, an adhesive resin layer containing a hydrogenated styrene-diene rubber block copolymer and a tackifier, and a heat seal resin layer. There is disclosed a multilayer film that can be exposed in an adhesive state in which an adhesive resin layer can be resealed at a heat seal portion when the multilayer film is peeled off from a bottom material.

  However, these multilayer films contain a large amount of hydrogenated rubber block copolymer as essential components in the adhesive resin layer and tackifying resins such as rosin resins, terpene resins, petroleum hydrocarbon resins as essential components. Contains. When this multilayer film is used for food packaging, the amount of extraction tends to increase in the elution test using n-heptane, which is a pseudo-solvent for oily food, for the tackifying resin. It is preferable not to mix the tackifier resin with the adhesive resin layer as much as possible.

  Further, in Patent Documents 2 and 3, a heat seal resin layer (corresponding to a welding layer in Patent Document 3) and this heat seal resin layer and a heat-sealable thermoplastic resin layer are heat sealed, and then peeled off. When the heat seal resin layer breaks, the heat seal resin layer and the adhesive resin layer (corresponding to the intermediate adhesive layer in Patent Document 3) peel off, and the adhesive resin layer is resealed at the heat seal portion. A package using a multilayer film characterized by being exposed in a possible adhesive state as a container lid is disclosed.

  However, in these packages, since the adhesive resin layer and the heat seal resin layer are directly adjacent, additives such as lubricants and antiblocking agents added to the heat seal resin layer after opening are exposed over time. There is a concern that the reseal peel strength with the adhesive resin layer may decrease due to bleeding on the surface of the heat seal resin layer.

  Patent Document 4 discloses a heat-sealing packaging material in which an adhesive resin layer (adhesive layer) and a heat seal agent layer are formed in this order on at least one surface of a base material, and the adhesive resin layer and the above-mentioned A packaging material is disclosed in which the adhesive strength between the heat sealant layers is smaller than the heat seal strength between the heat sealant layer and the layer to be heat sealed.

  Specifically, as an example, on a biaxially stretched polypropylene surface of a laminate film (thickness 50 μm) made of polyester and biaxially stretched polypropylene, 10% by mass of styrene and 90% by mass of a diene hydrocarbon are formed. Heat seal in which an adhesive resin layer having a thickness of 25 μm is laminated by extrusion lamination using a random copolymer with a hydrogenated product of a random copolymer, and a solvent-soluble acrylic heat seal lacquer is further coated on the adhesive resin layer The packaging material which laminated | stacked the agent layer is illustrated. In the case of a package body cut out in a circle with a tab and heat-sealed in a polystyrene container as a lid material, if the tab is pinched and pulled, peeling occurs at the interface between the adhesive resin layer and the heat-sealant layer, and the peeling occurs It is described that when a lid is placed on a container and pressure-bonded with a finger or the like, the adhesive resin layer re-adheres to the flange portion and is sealed again.

  However, the packaging body having the above structure has a process in which the adhesive resin is exposed to the outside before coating the heat sealing agent, and dust, dust, etc. floating in the atmosphere adhere to the adhesive resin. In some cases, resealability may be reduced, and special equipment such as a coater for coating and a drying equipment is required, resulting in an increase in manufacturing cost.

  The present inventors use the styrenic thermoplastic elastomer having specific viscoelastic properties as the main component of the adhesive resin layer, and arrange the release resin layer between the adhesive resin layer and the heat seal resin layer to achieve the above problem. Has been found to be able to be solved, and has already been commercialized (Patent Documents 5 to 9).

  On the other hand, the demand for food safety from consumers, retail stores, markets, etc. has increased further due to the recent impersonation of food, improper display of the shelf life, and foreign matter contamination problems. In order to reduce the risk that a third party intentionally puts foreign matter into the package, the package is given importance to prevent it from being tampered with or tampered with. It has become like this.

JP 2003-175567 A JP 2004-75181 A Special Table 2000-500722 JP 2005-41539 A Japanese Patent No. 4749119 Japanese Patent No. 4902237 Japanese Patent No. 5106795 Japanese Patent No. 51212244 Japanese Patent No. 5117225

  The present invention has been made in order to solve the problems of conventional multilayer films, and the solution is excellent in terms of food hygiene, good easy-openability, and good only by pressure and pressure bonding with hands and fingers. Another object of the present invention is to provide a multi-layer film with a reseal function that has both resealability and a function of preventing mischief and tampering, and a re-sealable package using the same.

  As a result of intensive studies, the present inventors have used a styrene-based thermoplastic elastomer having a specific viscoelastic property as a main component of the adhesive resin layer, and a specific glass between the adhesive resin layer and the heat seal resin layer. It has been found that the above problem can be solved by providing a release resin layer having a transition temperature, and the present invention has been completed.

  That is, the gist of the present invention is that the surface resin layer (A), the adhesive resin layer (B), the release resin layer (C), and the heat seal resin layer (D) are (A) / (B) / (C). The temperature at which the adhesive resin layer (B) exhibits a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement is − A multilayer with a reseal function, comprising a styrene-based thermoplastic elastomer at 35 ° C. or higher as a main component and the release resin layer (C) comprising a cyclic olefin resin having a glass transition temperature (Tg) of 100 to 150 ° C. A packaging body in which the bottom material and the lid material are heat-sealed by using the film as a lid material or a bottom material, and heat-sealing the heat-seal resin layer (D) of the multilayer film to the heat-sealed portion of the object to be sealed. The heat In the case where the adhesive resin layer (B) and the release resin layer (C) are delaminated in the package part, both layers are exposed in a resealable state, and the resealable packaging body Exist.

  ADVANTAGE OF THE INVENTION According to this invention, it is excellent in food hygiene, has a good easy-opening property, and a multi-layer film with a re-seal function having both good re-sealability only by pressure and pressure bonding with hands and fingers, and a lid using the same A material, a bottom material, and a resealable package can be provided, and the industrial value of the present invention is high.

It is a fragmentary sectional view of the package which used the film of the present invention for the lid. In the packaging body shown in FIG. 1, it is a fragmentary sectional view of the packaging body of the state which peeled a part of cover material from the container. In the package shown in FIG. 1, it is a fragmentary sectional view which shows the state which resealed the cover material and the bottom material. It is a fragmentary sectional view of the package which used the film of the present invention for the bottom material. In the package shown in FIG. 4, it is a fragmentary sectional view of the package in the state which peeled a part of cover material from the container. In the package shown in FIG. 4, it is a fragmentary sectional view which shows the state which resealed the cover material and the bottom material.

  Hereinafter, the multilayer film with a reseal function, a lid material, a bottom material, and a package of the present invention will be described in detail. In the present specification, “configured as a main component” is intended to allow other components to be included within a range that does not impede the action and effect of the resin constituting each layer. Furthermore, although this term does not restrict | limit specific content rate, it occupies 70-100 mass% of the whole component of each layer, Preferably it is 85-100 mass%, More preferably, it occupies 95-100 mass%. Means.

  In the film constituting the package of the present invention, the surface resin layer (A), the adhesive resin layer (B), the release resin layer (C) and the heat seal resin layer (D) are (A) / (B) / ( C) / (D) is a multilayer film laminated in order, and the temperature at which the adhesive resin layer (B) exhibits a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement A layer composed of a cyclic olefin resin having a styrene-based thermoplastic elastomer of −35 ° C. or higher as a main component and a glass transition temperature (Tg) of the release resin layer (C) of 100 ° C. or higher and 150 ° C. or lower; When the heat-sealing resin layer (D) is heat-sealed at a heat-sealing portion of a sealed object, and then the multilayer film is peeled from the heat-sealing portion, the adhesive resin layer (B) The release resin layer (C) is delaminated and the adhesive resin layer (B) is exposed in a re-sealable state with the release resin layer (C). is there.

  First, the surface resin layer (A) of the film constituting the package of the present invention will be described. The surface resin layer (A) is a layer composed of the thermoplastic resin (a) as a main component, and the delamination strength between the surface resin layer (A) and the adhesive resin layer (B) at the time of peeling is adhesive. The layer structure is not particularly limited as long as it is greater than the delamination strength between the resin layer (B) and the release resin layer (C), and may be a single layer or a multilayer.

  The thermoplastic resin (a) used as the main component of the surface resin layer (A) is the resin used as the main component of the adhesive resin layer (B), the release resin layer (C), and the heat seal resin layer (D). It is necessary to select appropriately considering the type. Since the thermoplastic resin (a) has a melt extrusion temperature in the range of approximately 180 to 300 ° C., a thermoplastic resin that can be melt extruded within this range is suitably used. Specific examples of the thermoplastic resin (a) include olefin resins (ethylene resins, propylene resins, cyclic olefin resins, etc.), amide resins, saponified ethylene-vinyl acetate copolymers, ester resins, Examples thereof include styrene resins and carbonate resins. These thermoplastic resins can be used alone or as a mixed resin composition of two or more, and can form a single layer structure or a multilayer structure.

  In the present invention, in view of molding processability, production cost, transparency, etc., the thermoplastic resin (a) includes olefin resin, amide resin, saponified ethylene-vinyl acetate copolymer, ester resin, and styrene. At least one thermoplastic resin selected from the group consisting of a series resin can be suitably used.

  Examples of the ethylene resin include ethylene resins such as very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE); Ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), ethylene-acrylic acid copolymer Polymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-glycidyl methacrylate copolymer (E-GMA), ethylene-vinyl acetate-glycidyl methacrylate copolymer (E-VA-GMA), ethylene- Maleic anhydride copolymer (E-MA ), Ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH), and the like; and further, metal-neutralized ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer Examples thereof include a metal neutralized product of coalescence. These may be used alone or in combination of two or more.

  Examples of the propylene-based resin include propylene homopolymers, copolymers of propylene and other α-olefins such as ethylene and butene, and the copolymers include any of random copolymers and block copolymers. Can also be used. The stereoregularity may be any of an isotactic structure, a syndiotactic structure, an atactic structure, a stereo block structure, and the like. These may be used alone or in combination of two or more.

  Examples of the amide-based resin include, as aliphatic polyamide polymers, ring-opening polymers of cyclic lactams, polycondensates of aminocarboxylic acids, and polycondensates of dicarboxylic acids and diamines. Specifically, a homopolymer of ε-caprolactam referred to as 6 nylon, polyhexamethylene adipamide referred to as 66 nylon, or 6-66 nylon as a copolymer thereof can be used. Moreover, as an aromatic polyamide polymer, a resin or the like containing 70 mol% or more of a polyamide constituent unit composed of xylylenediamine and an α, ω aliphatic dicarboxylic acid having 6 to 12 carbon atoms in the molecular chain. Can be used. Specifically, homopolymers such as polymetaxylylene adipamide, polymetaxylylene pimeramide, polymetaxylylene azeramide, polyparaxylylene azeramide, polyparaxylylene decanamide, metaxylylene / paraxylylene azamide Examples of the copolymer include a amide copolymer, a metaxylylene / paraxylylene pimeramide copolymer, a metaxylylene / paraxylylene azeramide copolymer, and a metaxylylene / paraxylylene sepacamide copolymer. These may be used alone or in combination of two or more.

  The saponified ethylene-vinyl acetate copolymer has an ethylene content of usually 29% or more, preferably 32% or more, and 47 mol% or less, preferably 44 mol% or less, and has a saponification degree. 90% or more, preferably 95% or more is suitably used. By selecting a grade in which the ethylene content and the degree of saponification are in the above ranges, the gas barrier properties and mechanical strength of the film can be improved. These may be used alone or in combination of two or more.

  Examples of the ester resin include polyethylene terephthalate resin, polypropylene terephthalate resin, polybutylene terephthalate resin, polyethylene isophthalate resin, polyethylene naphthalate resin, polybutylene naphthalate resin, polyethylene terephthalate / isophthalate copolymer resin, 1,4-cyclohexane. Represented by low crystalline or amorphous polyethylene terephthalate resin, polyethylene / neopentyl terephthalate copolymer resin, and polylactic acid resin containing dimethanol units in a total glycol monomer unit of 15 mol% to 50 mol%. Examples include aliphatic polyester resins.

  In addition, a thermoplastic polyester elastomer having a high melting point and high crystallinity aromatic polyester as a hard segment and an amorphous polyester or amorphous polyether as a soft segment may be appropriately mixed with the ester resin. These elastomers may be used alone or in a suitable mixture of two or more.

  Examples of the styrenic resin include general-purpose polystyrene (GPPS), high-impact polystyrene (HIPS), styrene- (meth) acrylic acid ester copolymer, and styrenic copolymer composed of a styrenic monomer and (meth) acrylic acid ester. Examples thereof include a resin containing 1% by mass to 20% by mass of a rubber-like elastic body as dispersed particles in the continuous phase. These may be used alone or in combination of two or more.

  The surface resin layer (A) is composed of two or more surface resin layers (A) in order to give the multilayer film functions such as gas barrier properties and pinhole resistance, and is composed of ethylene-vinyl acetate. It is preferable to have at least one layer mainly composed of a polymer saponified product and / or a layer mainly composed of an amide resin. However, when the surface resin layer (A) has a multilayer structure, the delamination strength between the resin layers constituting the multilayer is the delamination strength between the adhesive resin layer (B) and the release resin layer (C). It is also important to appropriately select and use an adhesive resin that is larger than that.

  Here, as the adhesive resin, ethylene-based resins such as linear low density polyethylene (LLDPE), low density polyethylene (LDPE), and ethylene-vinyl acetate copolymer (EVA), propylene homopolymer, and Propylene-based resins such as copolymers of propylene and other α-olefins, monobasic unsaturated fatty acids such as acrylic acid or methacrylic acid, or methyl acrylate, methyl methacrylate, or glycidyl methacrylate An olefin-based adhesive resin in which an ester compound of a monobasic unsaturated fatty acid or an anhydride of a dibasic fatty acid such as maleic acid, fumaric acid or itaconic acid is chemically bonded is preferably used. Specific examples of such an adhesive resin include trade name “Admer” manufactured by Mitsui Chemicals, Inc. and trade name “Modic” manufactured by Mitsubishi Chemical Corporation.

  Other components may be appropriately added to the surface resin layer (A) as long as the gist of the present invention is not impaired. Specific examples include components such as an antifogging agent, an antistatic agent, a heat stabilizer, a nucleating agent, an antioxidant, a lubricant, an antiblocking agent, a release agent, and an ultraviolet absorber. When the surface resin layer (A) has a multilayer structure, it may be added only to a specific layer or may be added to all layers.

  Next, the adhesive resin layer (B) of the film constituting the package of the present invention will be described. The adhesive resin layer (B) is mainly composed of a styrene-based thermoplastic elastomer (b) having a temperature showing a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement of −35 ° C. or more. It is important that the layer is constructed as Here, if the temperature showing the peak value of the loss tangent (tan δ) is −35 ° C. or higher, the pressure-sensitive adhesive layer (B) and the release resin layer (C) exposed at the time of peeling are only pressure-bonded by hand or fingers. It is preferable because of practical resealability. The resealability is presumed to be affected by viscoelastic properties at room temperature, particularly the value of loss tangent (tan δ), and the value of loss tangent (tan δ) at room temperature is 0.1 or more (upper limit) The value is usually more preferably about 0.6). Moreover, the upper limit of the temperature which shows the peak value of loss tangent (tan-delta) of a styrene-type thermoplastic elastomer (b) is 10 degrees C or less normally from the characteristic as an elastomer. Furthermore, since the film of the present invention may be used even in a low temperature environment such as a refrigeration facility represented by a refrigerator, in consideration of these, the temperature at which the peak value of loss tangent (tan δ) is shown. A preferable range is −35 ° C. or higher, more preferably −25 ° C. or higher, and 5 ° C. or lower, more preferably 0 ° C. or lower.

  The styrenic thermoplastic elastomer (b) is preferably styrene, a copolymer of a styrene homologue such as α-methylstyrene and a conjugated diene, or a hydrogenated derivative thereof. Here, examples of the conjugated diene constituting the conjugated diene portion include 1,3-butadiene, isoprene, 1,3-pentadiene, and the like. These may be used alone or in a state where two or more kinds are mixed in the copolymer. It may be included. However, the thermal stability and weather resistance when a double bond mainly consisting of vinyl bonds in the conjugated diene moiety remains are extremely poor. To improve this, 80% or more, preferably 95% of the double bonds. It is preferable to use one added with hydrogen.

  The temperature showing the peak value of the loss tangent (tan δ) of the styrenic thermoplastic elastomer (b) mainly consists of the styrene content and the vinyl bond content of the conjugated diene part (for example, 1,2 bond in the case of butadiene, isoprene). In this case, the amount depends on the amount of 1,2 and 3,4 bonds. In the present invention, the styrene content is 1% by mass or more, preferably 5% by mass or more, more preferably 10% by mass or more, 25% by mass or less, preferably 20% by mass or less, more preferably 15% by mass or less. A styrenic thermoplastic elastomer having a vinyl bond content of the conjugated diene moiety of 40 mol% or more, preferably 50 mol% or more is suitably used. Specific examples of such a styrenic thermoplastic elastomer include the product name “Hibler 7311” manufactured by Kuraray Co., Ltd., the product name “Tuftec H1221” manufactured by Asahi Kasei Co., Ltd., and the product name “Dynalon” manufactured by JSR Corporation. 1320P "etc. can be illustrated.

  Other resins and components may be appropriately added to the pressure-sensitive adhesive resin layer (B) as long as the gist of the present invention is not impaired. Specific examples include low crystalline or amorphous olefin resins, softeners, oils (mineral oils), stabilizers (antioxidants, etc.), liquid paraffin, and the like.

  Next, the release resin layer (C) of the film constituting the package of the present invention will be described. The release resin layer (C) is a layer composed mainly of the thermoplastic resin (c), and the delamination strength between the adhesive resin layer (B) and the release resin layer (C) during the peeling is the surface. Especially if it is a layer structure which becomes smaller than the delamination strength between the resin layer (A) and the adhesive resin layer (B) and between the release resin layer (C) and the heat seal resin layer (D) However, it may be a single layer or multiple layers as desired.

  In the present invention, the thermoplastic resin (c) contained as the main component of the release resin layer (C) is excellent in rigidity, and the adhesive resin layer ( B) and the release resin layer (C) can be prevented from roughening of the delamination surface and unevenness of each layer, and are easy to open and re-sealability when opening-resealing is repeated, and is industrially stable. In addition, a cyclic olefin-based resin that is an amorphous resin that can be obtained relatively inexpensively is preferably used. Among them, the cyclic olefin resin having a glass transition temperature (Tg) of 100 ° C. or higher and 150 ° C. or lower is excellent in molding processability and transparency, and is not delaminated or opened by a slight impact. Moreover, when it wants to open, it can peel easily. In general, in the case of a cyclic olefin having a Tg of 150 ° C. or higher, the ethylene content measured by the NMR method is usually less than 10% by weight, and the interlayer adhesive strength (initial peel strength) is too weak at less than 3 N / 15 mm width. There is a risk of breaking the package due to a drop impact.

  In addition, since the amorphous resin does not soften to the glass transition temperature, if the extrusion temperature is low, a large torque is required for plasticization, and a great burden is imposed on the extrusion equipment. On the contrary, since the cyclic olefin resin having a glass transition temperature (Tg) of less than 100 ° C. has an ethylene content measured by NMR method of 35% by weight or more, the interlayer adhesive strength (initial peel strength) is 20 N / 15 mm. It is too strong as described above, and there arises a problem that it is difficult to open the package.

  The cyclic olefin resin is an amorphous resin made by copolymerizing a cyclic olefin (polymer having an oleocyclic hydrocarbon group) and ethylene, and a cycloolefin copolymer (COC) obtained by addition polymerization of a norbornene derivative and an α-olefin. Or a cycloolefin polymer (COP) obtained by ring-opening polymerization of a cyclic olefin can be preferably used. Since both COC and COP have a bulky and rigid annular structure, they are characterized by being amorphous, excellent in transparency, and having a high elastic modulus.

  When an ester resin or an amide resin is used as the main component of the release resin layer (C), the part peeled off from the adhesive resin layer (B) and sealed again is the same as the part not opened. It becomes an appearance, and it cannot be easily determined whether it has been opened. On the other hand, when a cyclic olefin resin is used as the main component of the release resin layer (C), the peeled surface once opened becomes white and rough, so that it can be easily understood that it has been opened even after resealing. During the multilayer film coextrusion molding of the present invention, the ethylene components contained in each of the release layer resin (C) and the adhesive layer resin (B) are compatible, and at the initial opening, the release layer resin (C) and the adhesive layer resin (B It is thought that the peeled surface becomes white and rough due to cohesive failure. Since the peeled surface becomes white, it can be easily determined whether or not the package has been opened, which leads to prevention of mischief and tampering at stores such as supermarkets and retail stores.

For example, NMR measurement was performed as follows. That is, about 20 mg of a sample is dissolved by heating in about 1.5 g of orthodichlorobenzene. About 0.1 ml of deuterated benzene was previously charged in an NMR sample tube having an outer diameter of 5 mm, and the above sample was charged and sealed. Then, ¹ H-NMR and ¹³ C-NMR measurements were performed at 130 ° C. using a Bruker BioSpin AVANCE 400 type NMR measuring apparatus. The number of integrations was 256 for ¹ H-NMR and 8192 for ¹³ C-NMR. Each measured peak was assigned and qualified, and each component was quantified from the integrated value of each peak.

  Here, the COC resin can be easily obtained from each company, for example, trade name “TOPAS 6013F-04 (Tg = 138 ° C.)” manufactured by Polyplastics Co., Ltd. or trade name manufactured by Mitsui Chemicals, Inc. “Apel APL6013T (Tg = 125 ° C.)” can be exemplified. Moreover, as a COP resin, the brand name "ZEONOR 1020R (Tg = 102 degreeC)" by Nippon Zeon Co., Ltd. etc. can be illustrated, for example.

  The film constituting the package of the present invention constitutes the heat seal part of the sealed object by arranging the release resin layer (C) between the adhesive resin layer (B) and the heat seal resin layer (D). Without being limited to the resin to be used, it is possible to impart a good initial peel strength and resealability function with the adhesive resin layer (B). In the present invention, it is preferable to use, as the thermoplastic resin (c), a thermoplastic resin having an excellent initial peel strength from the adhesive resin layer (B) and resealability rather than the thermoplastic resin (d).

  Specifically, as the resin constituting the heat seal portion of the sealed object, an olefin resin that can be heat sealed under the heat seal conditions (temperature: about 120 to 180 ° C.) that are usually employed is mainly used. However, in the present invention, as the release resin layer (C) that exhibits good initial peel strength and resealability with the adhesive resin layer (B), as the cyclic olefin-based resin and the heat seal resin layer (D) A layer mainly composed of an olefin resin and / or a styrene thermoplastic elastomer can be preferably selected.

  In addition, in the release resin layer (C), in order to develop stable resealability between the adhesive resin layer (B) and the release resin layer (C), mixing with an additive that easily bleeds on the surface of the release resin layer (C) It is preferable not to do as much as possible.

  Next, the heat seal resin layer (D) of the film constituting the package of the present invention will be described. The heat seal resin layer (D) is a heat sealable resin layer composed mainly of the thermoplastic resin (d). The heat seal resin layer (D) is heat-sealed at the heat seal portion of the object to be sealed, and then when the multilayer film is peeled from the heat seal portion, the release resin layer (C) and the heat seal resin layer (D) There is no particular limitation as long as the layer peeling strength between the adhesive resin layer (B) and the peeling resin layer (C) is greater than the interlayer peeling strength. The resin layer may be a multi-layered resin layer.

  The thermoplastic resin (d) constituting the main component of the heat seal resin layer (D) is a sealed object when the film of the present invention is used as a cover material of a package or as a bottom material after deep drawing. Appropriate heat seal strength considering the material of the sealing surface of the lid and bottom material and the type of resin used as the main component of the surface resin layer (A), adhesive resin layer (B), and release resin layer (C) Such a resin can be appropriately selected and used. Examples of the thermoplastic resin (d) include ethylene resins, styrene resins, styrene thermoplastic elastomers, and the like. In the present invention, the release resin layer (C) and the heat seal resin layer (under a heat seal condition (temperature: about 120 to 180 ° C.) usually employed in various multilayer films are inexpensive and excellent in moldability. It is possible to suitably use an ethylene-based resin that can make the delamination strength between D) larger than the delamination strength between the adhesive resin layer (B) and the release resin layer (C).

  Examples of the ethylene resin include ethylene resins such as very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE); Ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), ethylene-acrylic acid copolymer Polymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-glycidyl methacrylate copolymer (E-GMA), ethylene-vinyl acetate-glycidyl methacrylate copolymer (E-VA-GMA), ethylene- Maleic anhydride copolymer (E-MA H) Ethylene copolymers such as ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH); further metal neutralized ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer Examples thereof include a metal neutralized product of coalescence. These may be used alone or in combination of two or more.

  The styrenic thermoplastic elastomer has a styrene content of 1% by mass or more, preferably 5% by mass or more, more preferably 10% by mass or more, 60% by mass or less, preferably 40% by mass or less, and more preferably. 35% by mass or less of styrene / isoprene / styrene block copolymer (SIS), styrene / butadiene / styrene block copolymer (SBS), styrene / isoprene block copolymer (SI), styrene / butadiene block copolymer ( SB), styrene / ethylene propylene / styrene block copolymer (SEPS), styrene / ethylene butylene / styrene block copolymer (SEBS), styrene / ethylene propylene block copolymer (SEP), styrene / ethylene butylene block copolymer Combined (SEB), steel Examples thereof include styrene block copolymers such as a lene / isobutylene / styrene block copolymer (SIBS) and a styrene / ethylene butylene / olefin crystal block copolymer (SEBC). These may be used alone or in combination of two or more.

  Moreover, the heat seal resin layer (D) makes the delamination strength between the release resin layer (C) larger than the delamination strength between the adhesive resin layer (B) and the release resin layer (C). Therefore, an adhesive resin layer containing an adhesive resin as a main component between the release resin layer (C) and the heat seal resin layer (D) is contained in the heat seal resin layer (D). (E) can be arranged.

  Here, examples of the adhesive resin include ethylene resins such as linear low density polyethylene (LLDPE), low density polyethylene (LDPE), and ethylene-vinyl acetate copolymer (EVA), propylene homopolymer, and propylene. Monopropylene unsaturated fatty acid such as acrylic acid or methacrylic acid, or monobasic such as methyl acrylate, methyl methacrylate, or glycidyl methacrylate Olefinic Adhesive Resin with Chemically Bonded Ester Compounds of Polyunsaturated Fatty Acids or Dibasic Fatty Acid Anhydrides such as Maleic Acid, Fumaric Acid or Itaconic Acid, and Styrene / Ethylene Butylene / Styrene Block Copolymer Combined (SEBS) and styrene / ethylene butylene Adhesion of styrene thermoplastic elastomers with polar functional groups such as carboxyl groups, acid anhydride groups, epoxy groups, and amino groups in styrene thermoplastic elastomers such as olefin crystal block copolymers (SEBC) Resin is preferably used.

  As a specific example of such an adhesive resin, in the former olefin-based adhesive resin, a product name “Admer” manufactured by Mitsui Chemicals, Inc., a product name “Modic” manufactured by Mitsubishi Chemical Corporation, and the like can be exemplified. . Examples of the latter styrene-based thermoplastic elastomer-based adhesive resin include the trade name “Dynalon” manufactured by JSR Corporation and the product name “Tuftec” manufactured by Asahi Kasei Chemicals Corporation.

  It is preferable to add a lubricant or an anti-blocking agent to the heat seal resin layer (D) as appropriate from the viewpoints of processing suitability during extrusion film formation and packaging suitability in a filling machine such as a deep drawing packaging machine. Here, when the surface resin layer (A) / adhesive resin layer (B) / heat seal resin layer (D) disclosed in Patent Document 1 are laminated in this order and the heat seal portion is peeled off, the adhesive resin layer In the multilayer film which peels between the layers of (B) and the heat seal resin layer (D), there are the following problems.

  That is, since the adhesive resin layer (B) and the heat seal resin layer (D) are directly adjacent to each other, additives such as a lubricant and an antiblocking agent added to the heat seal resin layer (D) after opening are changed over time. There is a concern that the reseal peel strength with the adhesive resin layer (B) may decrease due to bleeding on the exposed surface of the heat seal resin layer. On the other hand, like the film of the present invention, when the release resin layer (C) is disposed between the adhesive resin layer (B) and the heat seal resin layer (D), and the heat seal portion is peeled off, the adhesive is applied. In the multilayer film that delaminates between the resin layer (B) and the release resin layer (C), additives such as lubricants and antiblocking agents that are suitably added to the heat seal resin layer (D) are added to the delamination part. Since it is difficult to influence directly, there is also an advantage that stable resealability can be obtained with little influence on reseal strength.

  Furthermore, you may add suitably another component to the heat seal resin layer (D) in the range which does not impair the main point of this invention. Specific examples include antifogging agents, antistatic agents, heat stabilizers, nucleating agents, antioxidants, mold release agents, and ultraviolet absorbers.

  When the film constituting the package of the present invention heat-seal resin layer (D) of the film is heat-sealed at the heat-sealed portion of the sealed body, and then the multilayer film is peeled off from the heat-sealed portion, the adhesive resin layer The exposure of (B) is the breakage of the release resin layer (C) and the heat seal resin layer (D) from the multilayer film, the adhesive resin layer (B) and the release resin layer in the heat seal portion. Since it is performed by delamination with (C) and transition of the release resin layer (C) and the heat seal resin layer (D) to the sealed body side, as a combination of resins selected for each layer The delamination strength between the adhesive resin layer (B) and the release resin layer (C) is between the surface resin layer (A) and the adhesive resin layer (B), and the release resin layer (C) and the heat seal resin layer. During (D) It is necessary to become such a configuration smaller than that of the interlayer peel strength. At the same time, it is also important to ensure the delamination strength to such an extent that the function as a package can be maintained so that the layers are not easily peeled off or opened by a slight impact.

  From these viewpoints, as a combination of resins selected for the adhesive resin layer (B) and the release resin layer (C), the interlayer peel strength (initial peel strength) is in the range of 1 N / 15 mm width to 20 N / 15 mm width. It is preferable to select as follows. Here, if the delamination strength is 1 N / 15 mm width or more, problems such as easy opening of the packaging body due to a slight impact are unlikely to occur, and if it is 20 N / 15 mm width or less, the packaging body Is easy because it is easy to open by hand, which is preferable.

  In the present invention, the more preferable range of the interlaminar peel strength (initial peel strength) between the adhesive resin layer (B) and the release resin layer (C) has a lower limit of 3 N / 15 mm width or more, and more preferably 5 N / 15 mm. It is not less than the width and the upper limit is not more than 15 N / 15 mm width, more preferably not more than 10 N / 15 mm width.

  Next, with regard to resealability after opening, for example, the adhesive resin layer (B) and the release resin layer (C) after repeated opening and resealing a total of 5 times only by pressure pressing with hands or fingers. The delamination strength (reseal peel strength) is preferably 0.5 N / 15 mm width or more. Here, the reseal peel strength is 0.5 N / 15 mm width or more, preferably 0.75 N / 15 mm width or more, more preferably 1.0 N / 15 mm width or more (only re-seal strength is obtained by pressure bonding with hands or fingers). The upper limit of the sealing peel strength is not more than the delamination strength between the adhesive resin layer (B) and the release resin layer (C), preferably not more than 10 N / 15 mm width, more preferably not more than 5.0 N / 15 mm width. If so, it is preferable because practical resealability can be obtained.

  In the present invention, as a preferable combination of the surface resin layer (A), the adhesive resin layer (B), the release resin layer (C), and the heat seal resin layer (D) satisfying such a condition, as described above, the surface The resin layer (A) is mainly composed of at least one thermoplastic resin selected from the group consisting of an olefin resin, an amide resin, a saponified ethylene-vinyl acetate copolymer, an ester resin, and a styrene resin. A styrene-based thermoplastic elastomer having a temperature of −35 ° C. or higher, which is a layer having a structure and has a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement as an adhesive resin layer (B) A layer composed mainly of cyclic olefin resin is disposed as the release resin layer (C), and heat sealing is further performed. That arranged configured layer as a main component an ethylene-based resin as the fat layer (D) can be mentioned.

  Next, the thickness of each layer described above will be described. The surface resin layer (A) is a resin layer having a single layer or a multilayer structure, and usually has a thickness of 1 μm or more, preferably 10 μm or more, more preferably 20 μm or more, and 1000 μm or less, preferably 600 μm or less, Preferably it is 500 micrometers or less. Here, if the thickness of the surface resin layer (A) is 1 μm or more, it is easy to dispose a layer imparting characteristics such as gas barrier properties and pinhole resistance and an adhesive resin layer, and the thickness thereof. Is preferably 1000 μm or less, because heat can be easily transferred to the heat seal resin layer (D) during heat sealing, and can be easily heat sealed with the sealing portion of the object to be sealed.

  The adhesive resin layer (B) is usually a resin layer having a single layer structure, and the thickness thereof is not particularly limited, but the balance between easy-openability and resealability, moldability, production cost, etc. Therefore, 0.5 μm or more, preferably 5 μm or more, more preferably 10 μm or more and 100 μm or less, preferably 70 μm or less, more preferably 50 μm or less is suitably employed.

  The total thickness of the release resin layer (C) and the heat seal resin layer (D) is not particularly limited, but is 1 μm or more, preferably 3 μm or more, more preferably 5 μm or more, and 30 μm or less, preferably It is desirable that it is 25 μm or less, more preferably 15 μm or less. Here, if the total thickness is 1 μm or more, it is preferable because the deformation such as pressurization by a heat seal hot plate at the time of heat sealing can prevent problems such as deterioration of the function of each layer, and the thickness is also preferable. If it is 30 μm or less, the release resin layer (C) and the heat seal resin layer (D) can be easily broken when the adhesive resin layer (B) and the release resin layer (C) are peeled off. It is preferable because the layer (B) can be exposed in a resealable state.

  For the same reason, an adhesive resin layer (E) composed mainly of an olefin adhesive resin and / or a styrene thermoplastic elastomer between the release resin layer (C) and the heat seal resin layer (D). Even in the case of arranging, it is desirable that the total thickness is 1 μm or more, preferably 3 μm or more, more preferably 5 μm or more, 30 μm or less, preferably 25 m or less, more preferably 15 μm or less.

  Further, the thickness of the release resin layer (C) is 0.5 μm or more, preferably 2 μm or more, more preferably 3 μm or more and 29.5 μm or less, preferably 20 μm or less, more preferably 10 μm or less. If the thickness of the release resin layer (C) is 0.5 μm or more, the release resin layer (C) is deformed by the heat sealing pressure during heat sealing, and there are few problems such as a decrease in the function as the release resin layer. If the thickness is 29.5 μm or less, even when a resin having high rigidity such as an ester resin is disposed on the release resin layer (C), it is easily broken at the time of opening and the film remains. This is preferable because it is difficult for problems such as these to occur.

Next, the manufacturing method of the film which comprises the package of this invention is demonstrated.
In the present invention, the method for producing the film is not particularly limited, but a coextrusion method excellent in protection of the adhesive resin layer (B), productivity, hygiene and the like can be suitably used. That is, each resin composition used for the surface resin layer (A), the adhesive resin layer (B), the release resin layer (C), and the heat seal resin layer (D) described above is heated and melted in a separate extruder, After being laminated in the order of (A) / (B) / (C) / (D) in a molten state by a known method such as a multi-manifold method or a feed block method, a multilayer film is formed by a T-die / chill roll method or an inflation method. Can be molded. Here, in order to improve printing suitability and laminate suitability, it is preferable to perform a surface treatment on the surface of the outermost layer of the surface resin layer (A) of the obtained multilayer film. Examples of the surface treatment include corona treatment, plasma treatment, chromic acid treatment, flame treatment, surface oxidation treatment such as hot air treatment ozone / ultraviolet treatment, and surface unevenness treatment such as sand blasting. Corona treatment is preferably used from the viewpoint of treatment effect, productivity, and manufacturing cost.

  The film used in the present invention may be formed on the surface resin layer (A) opposite to the surface on which the adhesive resin layer (B) is laminated by a known method such as a dry lamination method or an extrusion lamination method, if necessary. A laminate base material can be laminated through an adhesive resin, an adhesive, or the like to obtain a laminate film or laminate sheet. Here, the laminate substrate is not particularly limited. For example, a biaxially stretched polypropylene film, a biaxially stretched nylon film, a biaxially stretched polyethylene terephthalate film, an unstretched polypropylene sheet, an unstretched polyethylene terephthalate sheet, An aluminum foil, paper, a nonwoven fabric, etc. are mentioned. In the present invention, a dry lamination method is preferably used, and examples of the adhesive used at that time include a polyester-polyurethane adhesive and a polyether-polyurethane adhesive.

  In the present invention, the film itself or a laminate film or laminate sheet obtained by laminating a film and a laminate base material can be used as a cover material or a bottom material of various packaging bodies, respectively. For example, when a laminate film is used as a lid for a package (container), the package (container) (sealed body) filled with a heat seal resin layer (D) of the lid and contents such as food By overlapping and heat-sealing with the heat-sealing resin layer, a package (container) having airtightness, practical initial peel strength, and resealing function can be obtained. This package (container) is exposed on the peeled surface after opening in a state where the adhesive resin layer (B) can be resealed, and can be resealed only by pressure pressing with a hand or a finger. Moreover, as a bottom material of various packaging bodies (containers), it is possible to obtain a packaging body (container) having a reseal function similarly by performing deep drawing or the like.

  Next, the resealing function in a deep-drawn package using the above film as a lid or bottom material will be described. FIG. 1 is a partial cross-sectional view of a deep-drawn package using the film of the present invention as a lid, and FIG. 2 is a diagram of the deep-drawn package shown in FIG. FIG. 3 is a partial cross-sectional view showing a state in which the lid and the bottom material are resealed in the deep-drawn package shown in FIG. 2. FIG. 4 is a partial cross-sectional view of a deep-drawn package using the film of the present invention as a bottom material, and FIG. 5 shows a part of the lid material from the bottom material in the deep-drawn package shown in FIG. FIG. 6 is a partial cross-sectional view of the deep-drawn package body in a peeled state, and is a partial cross-sectional view showing a state in which the lid material and the bottom material are resealed in the deep-drawn package body shown in FIG. 5.

  1 to 3, reference numeral 1 is a lid member, reference numeral 2 is a bottom material (sealed body), reference numeral 3 is a surface resin layer of the lid member, reference numeral 4 is an adhesive resin layer of the lid member, and reference numeral 5 is a lid member. The reference numeral 6 is a heat seal resin layer of the lid material, 7 is a surface resin layer of the bottom material, 8 is a heat seal resin layer of the bottom material, 9 is a heat seal portion, 10 is a tab portion, Reference numeral 11 denotes an exposed portion of the adhesive resin layer 4 at the time of peeling, and reference numeral 12 denotes an exposed portion of the peeling resin layer 5 at the time of peeling.

  4 to 6, reference numeral 41 is a bottom material, reference numeral 42 is a lid member (sealed body), reference numeral 43 is a bottom surface resin layer, reference numeral 44 is a bottom adhesive resin layer, and reference numeral 45 is a bottom material. Peeling resin layer, reference numeral 46 is a heat seal resin layer of the bottom material, reference numeral 47 is a surface resin layer of the cover material, reference numeral 48 is a heat seal resin layer of the cover material, reference numeral 49 is a heat seal portion of the cover material, and reference numeral 50 is a cover. The tab part of the material, reference numeral 51 is an exposed part of the adhesive resin layer 44 at the time of peeling, and reference numeral 52 is an exposed part of the peeling resin layer 45 at the time of peeling.

  When the film of the present invention is used as a lid of a deep drawn package, as shown in FIG. 1, the lid 1 is composed of a surface resin layer 3, an adhesive resin layer 4, a release resin layer 5, and a heat seal resin layer 6. It is composed in this order. The heat seal resin layer 6 of the lid 1 is heat-sealed with the heat seal resin layer 8 of the bottom material 2 that is the object to be sealed. That is, the lid member 1 and the bottom member 2 are bonded by the heat seal portion 9 formed by heat sealing.

  When the tab portion 10 provided on the lid member 1 is picked and pulled, as shown in FIG. 2, in the heat seal portion 9, first, the release resin layer 5 and the heat seal resin layer 6 on the tab portion 10 side are separated from the lid material 1. While being broken, peeling is started between the adhesive resin layer 4 and the release resin layer 5 in the lid member 1. When peeling between the adhesive resin layer 4 and the release resin layer 5 reaches the heat seal portion 9 on the side opposite to the tab portion 10 side, the release resin layer 5 and the heat seal resin layer 6 of the lid 1 are broken. The release resin layer 5 and the heat seal resin layer 6 of the lid material 1 that has been broken move to the bottom material 2 side that is a sheet body, and the exposed portion 11 of the adhesive resin layer 4 and the exposed portion 12 of the release resin layer 5 It is formed.

  In the case of resealing, as shown in FIG. 3, the peeled cover material 1 is covered on the bottom material 2, and the surface resin layer 3 is pressure-bonded by hand or fingers to form the adhesive resin layer 4 of the cover material 1. By overlapping the exposed portion 11 and the exposed portion 12 of the release resin layer 5 of the lid material 1 that has moved to the bottom material 2, the lid material 1 and the bottom material 2 can be resealed.

  On the other hand, when the film of the present invention is used as a bottom material of a deep-drawn package, as shown in FIG. 4, the bottom material 41 includes a surface resin layer 43, an adhesive resin layer 44, a release resin layer 45, and a heat seal resin. The layers 46 are laminated in this order. As in FIG. 1, the lid member 42 and the bottom member 41 are bonded together by a heat seal portion 49 formed by heat sealing.

  When the tab portion 50 provided on the lid 42 is pinched and pulled, as shown in FIG. 5, first, in the heat seal portion 49, the release resin layer 45 and the heat seal resin layer 46 on the tab portion 50 side are first broken from the bottom 41. At the same time, peeling is started between the adhesive resin layer 44 and the release resin layer 45 in the bottom material 41. When the peeling between the adhesive resin layer 44 and the release resin layer 45 reaches the heat seal portion 49 on the side opposite to the tab portion 50 side, the release resin layer 45 and the heat seal resin layer 46 of the bottom material 41 are broken. The peeled resin layer 45 and the heat seal resin layer 46 of the broken bottom material 41 are transferred to the lid member 42 that is the sheet body, and the exposed portion 51 of the adhesive resin layer 44 and the exposed portion 52 of the surface resin layer 45 are separated. It is formed.

  Then, as shown in FIG. 6, when resealing, cover the peeled lid material 42 on the bottom material 41, and press and pressure-bond the surface resin layer 47 of the lid material with a hand or a finger to obtain the bottom material. The cover material 42 and the bottom material 41 can be resealed by overlapping the exposed portion 51 of the adhesive resin layer 44 of 41 and the exposed portion 52 of the release resin layer 45 of the bottom material 41 transferred to the cover material 42. .

  The package constituted by the film of the present invention can be used as a lid or bottom material for various containers, and its use is not particularly limited. For example, instant noodles, snack confectionery, chocolate confectionery, slices Products such as ham and other processed meat products, wet tissue, sweat paper, fragrances, disposable diapers, etc. used as containers packaged in units of several units, or opened and used each time cosmetics and sanitary products, ship medicines, emergency adhesive plasters It can be used as a container for packaging pharmaceutical products such as throat lozenges. In particular, it can be suitably used as a package for storing contents that remain susceptible to deterioration such as oxidative deterioration, moisture absorption, and drying after the opening.

  The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. In addition, the various measured value and evaluation about the film displayed in this specification were performed as follows. Here, the flow direction from the extruder of the film is called the vertical direction, and the orthogonal direction is called the horizontal direction.

(1) Temperature showing peak value of loss tangent (tan δ) A sample was cut into a length of 4 mm and a width of 60 mm, and a viscoelastic spectrometer DVA-200 (manufactured by IT Measurement Co., Ltd.) was used, with a vibration frequency of 10 Hz and a strain of 0.1. %, Temperature rising rate of 3 ° C./min, 25 mm between chucks, the transverse direction was measured from −100 ° C., and the temperature showing the peak value of loss tangent (tan δ) was determined from the obtained data.

(2) Initial peeling strength The bottom material of the obtained deep-drawn package and the heat seal part of the lid were cut into strips having a width of 15 mm and used as test pieces. When this test piece is pulled at an angle of 180 degrees under the conditions of a temperature of 23 ° C. and a tensile speed of 200 mm / min using a universal testing machine (manufactured by Intesco), peeling when the bottom material and the lid material are peeled The strength was measured as the initial peel strength (N / 15 mm width).

(3) Membrane remaining situation The situation when peeled by hand from the bottom seal of the obtained deep-drawn package and the heat seal part of the lid was visually evaluated according to the following criteria.
○: When the resin layer breaks cleanly and there is no film residue or fluffing ×: When the resin layer cannot be broken or film breakage or fluffing occurs even when broken

(4) Reseal peel strength After opening from the heat-sealed portion of the deep-drawn package, the lid and the container were resealed again by pressure and pressure, and then the opening and resealing were repeated a total of 5 times. Peel strength (reseal peel strength) was measured under the same conditions as (2) initial peel strength. In addition, the following standards are also shown.
○: When the reseal peel strength is 0.5 N / 15 mm width or more ×: When the reseal peel strength is less than 0.5 N / 15 mm width

(5) Appearance of the reseal surface The appearance after the product was opened by hand from the heat-seal part of the bottom material and the cover material of the deep-drawn package and sealed again was visually evaluated according to the following criteria.
○: When the resealed part is white and can be easily distinguished from the unopened part. ×: When the resealed part is transparent and difficult to distinguish from the unopened part.

Example 1:
[Cover material]
The surface resin layer (A) has a three-layer structure using the following three types of resins.
A1: Saponified ethylene-vinyl acetate copolymer (manufactured by Kuraray Co., Ltd., trade name “Eval E105”, hereinafter abbreviated as “EVOH”)
A2: 6-66 nylon resin (Mitsubishi Engineering Plastics Co., Ltd., trade name “Novamid 2030”, hereinafter abbreviated as “6-66Ny”)
A3: Olefin-based adhesive resin (manufactured by Mitsui Chemicals, trade name “Admer N F558”, hereinafter abbreviated as “AD1”)

  The pressure-sensitive adhesive resin layer (B) is a styrene-based thermoplastic elastomer (manufactured by Kuraray Co., Ltd., trade name “HIBLER 7311”, styrene content: 12% by mass, temperature showing a peak value of loss tangent (tan δ): −18.6 And tan δ value at 20 ° C .: 0.19, hereinafter abbreviated as “TPS1”).

  The release resin layer (C) is a cycloolefin copolymer resin (manufactured by Polyplastics Co., Ltd., trade name “TOPAS 6013F-04”, glass transition temperature (Tg): 138 ° C., hereinafter abbreviated as “COC”), The heat seal resin layer (D) is composed of linear low density polyethylene (Ube Maruzen polyethylene trade name “Umerit 2040FC”, hereinafter abbreviated as “LLDPE”) with 1000 ppm of erucamide as a lubricant and natural silica as an antiblocking agent. Each was composed of a resin composition in which 2000 ppm was added and mixed.

  (A) Extruder for layer (single screw extruder of 50 mm in diameter for all three layers), (B) Extruder for layer (single screw extruder of 50 mm in diameter), (C) Extruder for layer (caliber) 50 mm single screw extruder) and (D) layer extruder (50 mm bore single screw extruder) Co-extruded under the conditions of a temperature of 190 to 230 ° C. and a T-die set temperature of 235 ° C., and the average of each layer in a six-layer configuration of (A1) / (A2) / (A3) / (B) / (C) / (D) A multilayer film (X1) having a thickness of 10 μm / 20 μm / 10 μm / 20 μm / 5 μm / 5 μm and a total thickness of 70 μm was obtained.

  Next, on the outermost layer side of the surface resin layer (A) of the obtained multilayer film (X1), a biaxially stretched polyethylene terephthalate film substrate (trade name “Embret PET”, thickness 16 μm, manufactured by Unitika Ltd.) is placed. Lamination film (X1LF) having a total thickness of 86 μm was obtained by laminating by a dry lamination method, and used as a lid for a package.

  In addition, as an adhesive for dry lamination, a two-component curable adhesive (manufactured by Dainippon Ink Co., Ltd. as a main agent, trade name “Dick Dry LX-75A”, a trade name of Dainippon Ink, Ltd. “Dick Dry KW-40” was used.

[Bottom material]
From the outermost layer side, EVOH, 6-66Ny, AD1, linear low density polyethylene resin (manufactured by Nippon Polyethylene Co., Ltd., trade name “NOVATEC LL UF240”, hereinafter abbreviated as “LLDPE”) as erucic acid amide as a lubricant Is laminated in the order of a resin composition (heat seal resin layer) in which 1000 ppm of natural silica is added and mixed as an antiblocking agent, and the average thickness of each layer is 10 μm / 20 μm / 10 μm / 30 μm, respectively, and the total thickness is 70 μm. A multilayer film (Y1) was obtained by coextrusion. An unstretched polyethylene terephthalate sheet (Mitsubishi Chemical Co., Ltd., trade name “Novaclear”) having a total thickness of 250 μm is bonded to the outermost layer side (EVOH surface) of this multilayer film (Y1) by a dry lamination method. A laminate sheet (Y1LS) having a thickness of 320 μm was obtained and used as the bottom material of the package. In addition, the grade similar to the case where a laminate film (X1LF) is produced was used as an adhesive for dry lamination.

[Deep-drawn packaging]
Using a deep-drawing packaging machine (manufactured by Mulchback, model number: R-530), the bottom material (Y1LS) is deep-drawn so that the non-stretched polyethylene terephthalate sheet layer is an outer layer, and the length is 130 mm. The container is processed into a rectangular container having a width of 170 mm and a flange width of 6 mm. In the heat seal portion, the above-mentioned cover material (X1LF) is applied to the flange portion provided on the deeply drawn bottom material, and the heat seal temperature: 140 A deep-drawn package was produced by heat sealing under the conditions of ° C., sealing time: 2 seconds, and sealing pressure: 4 kg / cm 2. The results of evaluation using this deep-drawn package are shown in Table 1.

Example 2:
[Cover material]
In Example 1, the resin used for the adhesive resin layer (B) was 190 parts by mass of TPS used in Example 1 and 10 parts by mass of ionomer resin (manufactured by Mitsui DuPont Polychemical Co., Ltd., trade name “1601”). Each layer has a six-layer configuration of (A1) / (A2) / (A3) / (B) / (C) / (D) in the same manner as in Example 1 except that the resin composition is changed to a mixed resin composition. The multilayer film (X2) having an average thickness of 10 μm / 20 μm / 10 μm / 20 μm / 5 μm / 5 μm and a total thickness of 70 μm was obtained. Next, in the same manner as in Example 1, a biaxially stretched polyethylene terephthalate film base material was bonded by a dry lamination method to obtain a laminate film (X2LF) having a total thickness of 86 μm, which was used as a lid for a package.

[Bottom material]
As in Example 1, a laminate sheet (Y1LS) was used as the bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Example 3:
[Cover material]
The surface resin layer (A) has a two-layer structure using the following two types of resins.
A1: EVOH
A2: AD1

  The adhesive resin layer (B) was constructed using TPS1 as in Example 1.

  For the release resin layer (C), a cycloolefin polymer resin (manufactured by Polyplastics Co., Ltd., trade name “ZEONOR 1020R”, glass transition temperature (Tg): 102 ° C., hereinafter abbreviated as “COP”) is used. Configured.

  Similarly to Example 1, the heat seal resin layer (D) was composed of a resin structure in which LLDPE was mixed with 1000 ppm of erucamide as a lubricant and 2000 ppm of natural silica as an antiblocking agent.

  (A) Extruder for layer (single-screw extruder with a diameter of 50 mm for both layers), (B) Extruder for layer (single-screw extruder with a diameter of 50 mm), (C) Extruder for layer (caliber) 50 mm single-screw extruder) and (D) each extruder of a T-die / chill roll co-extrusion multilayer film production apparatus having a layer extruder (both layers have a diameter of 50 mm). , Coextrusion under conditions of extrusion set temperature 190-230 ° C. and T die set temperature 235 ° C., each layer in a 6-layer configuration of (A1) / (A2) / (B) / C) / (E) / (D) A multilayer film (X3) having an average thickness of 15 μm / 22 μm / 20 μm / 5 μm / 3 μm / 5 μm and a total thickness of 70 μm was obtained. Subsequently, in the same manner as in Example 1, a biaxially stretched polyethylene terephthalate film base material was bonded by a dry lamination method to obtain a laminate film (X3LF) having a total thickness of 86 μm, and was used as a lid for a package.

[Bottom material]
As in Example 1, a laminate sheet (Y1LS) was used as the bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Example 4:
[Cover material]
Dry lamination of a biaxially stretched polyethylene terephthalate film substrate (manufactured by Unitika Ltd., trade name “Embret PET”, thickness 16 μm) on the outermost layer side (EVOH surface) of the multilayer film (Y1) produced in Example 1 By laminating by the method, a laminate film (Y1LF) having a total thickness of 86 μm was obtained and used as a cover material of the package.

[Bottom material]
On the outermost layer side (EVOH surface) of the multilayer film (X1) produced in Example 1, an unstretched polyethylene terephthalate sheet (trade name “Novaclear”, manufactured by Mitsubishi Chemical Corporation) with a total thickness of 250 μm was dry lamination method. To obtain a laminate sheet (X1LS) having a total thickness of 320 μm and used as a bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Example 5:
[Cover material]
In the same manner as in Example 4, a laminate film (Y1LF) was used as a lid for the package.

[Bottom material]
On the outermost layer side (EVOH surface) of the multilayer film (X2) produced in Example 2, an unstretched polyethylene terephthalate sheet having a total thickness of 250 μm (manufactured by Mitsubishi Chemical Corporation, trade name “Novaclear”) was obtained by a dry lamination method. A laminate sheet (X2LS) having a total thickness of 320 μm was obtained by bonding, and used as a bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Comparative Example 1:
[Cover material]
In Example 1, the release resin layer (C) was not disposed, and the average thickness of each layer was 10 μm / each with a five-layer configuration of (A1) / (A2) / (A3) / (B) / (D). A multilayer film (X5) having a total thickness of 65 μm was obtained in the same manner as in Example 1 except that the thickness was changed to 20 μm / 10 μm / 20 μm / 5 μm. Next, in the same manner as in Example 1, a biaxially stretched polyethylene terephthalate film base material was bonded by a dry lamination method to obtain a laminate film (X5LF) having a total thickness of 81 μm, and used as a cover material for a package.

[Bottom material]
As in Example 1, a laminate sheet (Y1LS) was used as the bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Comparative Example 2:
[Cover material]
In Example 1, the resin used for the adhesive resin layer (B) was changed from TPS1 to a styrene-based thermoplastic elastomer (manufactured by Asahi Kasei Co., Ltd., trade name “Tuftec H1052”, styrene content: 20 mass%, loss tangent (tan δ). (A1) / (A2) in the same manner as in Example 1 except that the temperature indicating the peak value: −42.2 ° C., tan δ value at 20 ° C .: 0.06, hereinafter abbreviated as TPS2) ) / (A3) / (B) / (C) / (D), the average thickness of each layer is 10 μm / 20 μm / 10 μm / 20 μm / 5 μm / 5 μm, and the total thickness is 70 μm. A multilayer film (X6) was obtained. Next, in the same manner as in Example 1, a biaxially stretched polyethylene terephthalate film base material was bonded by a dry lamination method to obtain a laminate film (X6LF) having a total thickness of 86 μm, and was used as a lid for a package.

[Bottom material]
As in Example 1, a laminate sheet (Y1LS) was used as the bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Comparative Example 3:
[Cover material]
In Example 1, the resin used for the release resin layer (C) is COC having a glass transition temperature of 138 ° C., manufactured by Polyplastics Co., Ltd., trade name “TOPAS 8007F-04”, glass transition temperature (Tg): 78 ° C., hereinafter abbreviated as “COC2”. ) Except that the average thickness of each layer is the same as in Example 1 except for the six-layer configuration of (A1) / (A2) / (A3) / (B) / (C) / (D). A multilayer film (X7) having a thickness of 10 μm / 20 μm / 10 μm / 20 μm / 5 μm / 5 μm and a total thickness of 70 μm was obtained. Next, in the same manner as in Example 1, a biaxially stretched polyethylene terephthalate film base material was bonded by a dry lamination method to obtain a laminate film (X7LF) having a total thickness of 86 μm, which was used as a lid for a package.

[Bottom material]
As in Example 1, a laminate sheet (Y1LS) was used as the bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Comparative Example 4:
[Cover material]
In Example 1, the resin used for the release resin layer (C) is COC having a glass transition temperature of 138 ° C., manufactured by Polyplastics Co., Ltd., trade name “TOPAS 6017”, glass transition temperature (Tg): 180 ° C., Hereinafter, it is abbreviated as “COC3”. ) Except that the average thickness of each layer is the same as in Example 1 except for the six-layer configuration of (A1) / (A2) / (A3) / (B) / (C) / (D). A multilayer film (X8) having a thickness of 10 μm / 20 μm / 10 μm / 20 μm / 5 μm / 5 μm and a total thickness of 70 μm was obtained. Subsequently, in the same manner as in Example 1, a biaxially stretched polyethylene terephthalate film base material was bonded by a dry lamination method to obtain a laminate film (X8LF) having a total thickness of 86 μm, and was used as a lid for a package.

[Bottom material]
As in Example 1, a laminate sheet (Y1LS) was used as the bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

Reference example:
[Cover material]
In Example 1, in a six-layer configuration of (A1) / (A2) / (A3) / (B) / (C) / (D), only the thickness of the release resin layer (C) was 40 μm, and the average of each layer A multilayer film (X7) having a total thickness of 105 μm was obtained in the same manner as in Example 1 except that the thickness was changed to 10 μm / 20 μm / 10 μm / 20 μm / 40 μm / 5 μm, respectively. Next, in the same manner as in Example 1, a biaxially stretched polyethylene terephthalate film base material was bonded together by a dry lamination method to obtain a laminate film (X7LF) having a total thickness of 121 μm, which was used as a lid for a package.

[Bottom material]
As in Example 1, a laminate sheet (Y1LS) was used as the bottom material of the package.

[Deep-drawn packaging]
A deep-drawn package was produced in the same manner as in Example 1. The results of evaluation using this deep-drawn package are shown in Table 1.

From Table 1, the re-sealable packaging body (deep-drawing packaging body) formed of the lid material or bottom material using the film defined in the present invention has all of the initial peel strength, the remaining film condition and the reseal peel strength. It was confirmed that the characteristics were practical and practical (Examples 1 to 5).
On the other hand, in the case of a package formed of a cover material using a film in which no release resin layer is disposed between the adhesive resin layer and the heat seal resin layer, the initial peel strength is too large, so it can be easily done by hand. It was difficult to open. In addition, when the resealing strength is insufficient (Comparative Example 1) or a styrene-based thermoplastic elastomer having viscoelastic properties outside the range specified in the present invention is used for the adhesive resin layer, the resealing peeling is performed. The strength was insufficient (Comparative Example 2). When a cyclic olefin-based resin having a glass transition temperature outside the range specified in the present invention is used for the release resin layer, it is difficult to discriminate between the resealed part and the unopened part (Comparative Example 3, Comparative Example). 4).
In addition, when the total thickness of the adhesive resin layer and the heat seal resin layer becomes thick (when it exceeds 30 μm), the peel resin layer and the heat seal resin layer cannot be broken when peeled by hand from the heat seal portion, and the film remains. (Reference example).

  The package of the present invention can be suitably used as a resealable package requiring prevention of mischief and tampering.

DESCRIPTION OF SYMBOLS 1 Cover material 2 Bottom material 3 Cover resin surface resin layer 4 Cover material adhesive resin layer 5 Cover material peeling resin layer 6 Cover material heat seal resin layer 7 Bottom material surface resin layer 8 Bottom material heat seal resin layer DESCRIPTION OF SYMBOLS 9 Heat seal part of bottom material 10 Tab part of lid material 11 Exposed part of adhesive resin layer at the time of peeling 12 Exposed part of heat seal resin layer at the time of peeling 41 Bottom material 42 Lid material 43 Surface resin layer of bottom material 44 Bottom material Adhesive resin layer 45 Base material release resin layer 46 Base material heat seal resin layer 47 Surface resin layer of lid material 48 Heat seal resin layer of lid material 49 Heat seal part of lid material 50 Tab part of lid material 51 During peeling Exposed part of adhesive resin layer in 52 Exposed part of release resin layer during peeling

Claims (9)

The surface resin layer (A), the adhesive resin layer (B), the release resin layer (C), and the heat seal resin layer (D) are laminated in the order of (A) / (B) / (C) / (D). A styrenic heat in which the adhesive resin layer (B) has a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement and is at least −35 ° C. A multi-layer film with a reseal function, which comprises a plastic elastomer as a main component and the release resin layer (C) is composed of a cyclic olefin resin having a glass transition temperature (Tg) of 100 to 150 ° C., is used as a lid or bottom material. The heat sealing resin layer (D) of the multilayer film is a package in which the bottom material and the lid material are heat sealed by heat sealing the heat sealing resin layer (D) to the heat sealed portion of the object to be sealed. Adhesive When fat layer (B) and the release resin layer and (C) is delaminated, reclosable package, characterized in that both layers are exposed at the resealable state. The exposure of the adhesive resin layer (B) is, in the heat seal part, the breakage of the heat seal resin layer (C) from the multilayer film, the delamination between the adhesive resin layer (B) and the heat seal resin layer (C), The resealable packaging body according to claim 1, which is performed by transferring the heat seal resin layer (C) to the sealed body side. The surface resin layer (A) is mainly composed of at least one thermoplastic resin selected from the group consisting of olefin resin, amide resin, saponified ethylene-vinyl acetate copolymer, ester resin, and styrene resin. The resealable packaging body according to claim 1 or 2, which is configured as follows. The resealable packaging body according to any one of claims 1 to 3, wherein the heat seal resin layer (D) contains an olefin resin or a styrene thermoplastic elastomer as a main component. The resealable packaging body according to any one of claims 1 to 4, wherein the release resin layer (C) has an ethylene content of 10 to 35% by weight as measured by NMR. The resealable package according to any one of claims 1 to 5, wherein the surface resin layer (A) is a layer mainly composed of a saponified ethylene-vinyl acetate copolymer or a polyamide-based resin. An adhesive resin layer (E) composed mainly of an olefin-based adhesive resin and / or a styrene-based thermoplastic elastomer-based adhesive resin is provided between the release resin layer (C) and the heat seal resin layer (D). The resealable packaging body according to any one of claims 1 to 6. The resealable packaging body according to any one of claims 1 to 7, wherein the total thickness of the release resin layer (C) and the heat seal resin layer (D) is 1 to 30 µm. The resealable packaging body according to claim 7 or 8, wherein the total thickness of the release resin layer (C), the adhesive resin layer (E), and the heat seal resin layer (D) is 1 to 30 µm.

Images