JP2010269515A - Laminate film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas barrier laminate film showing an excellent laminate strength even when printing is applied onto a base material for manufacturing the laminate film by laminating a sealant layer on the base material. <P>SOLUTION: In the laminate film obtained by laminating at least an ink layer, an adhesive layer and the sealant layer in the order on the base material, the ink layer contains a silane coupling agent; an adhesive agent forming the adhesive agent layer contains, as a major component, an epoxy resin composition composed of an epoxy resin and an epoxy resin curing agent; and an epoxy resin cured substance obtained by curing the epoxy resin composition contains a predetermined amount or more of a skeleton structure derived from xylylenediamine. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a laminate film. More specifically, the present invention relates to a laminate film used for packaging materials such as foods and pharmaceuticals for the purpose of preserving contents using an adhesive excellent in shielding various gases.

  In recent years, composite flexible films combining different kinds of polymer materials have become mainstream as packaging materials for reasons such as strength, product protection, workability, and advertising effects due to printing. Such a composite film is generally composed of a thermoplastic film layer as an outer layer having a role of protecting a product and a thermoplastic film layer as a sealant layer. A dry laminating method in which the sealant layer is applied by applying an adhesive, and an extrusion laminating method is applied to the laminated film by pressing the molten plastic film that becomes the sealant layer after applying an anchor coating agent to the laminated film as necessary. ing.

  In addition, the adhesive used in these methods is generally a two-component polyurethane adhesive composed of a main agent having an active hydrogen-containing group such as a hydroxyl group and a curing agent having an isocyanate group, from the viewpoint of high adhesive performance. (See Patent Documents 1 and 2).

  However, since these two-component polyurethane adhesives are generally not so fast in curing reaction, they are accelerated by aging over a long period of 1 to 5 days after bonding to ensure sufficient adhesion. Had to do. In addition, since a curing agent having an isocyanate group is used, when an unreacted isocyanate group remains after curing, the residual isocyanate group reacts with moisture in the atmosphere to generate carbon dioxide. There were problems such as the generation of bubbles. As a method for solving these problems, polyurethane adhesives and epoxy laminate adhesives have been proposed (see Patent Documents 3 to 4).

  However, the above-mentioned polyurethane-based adhesives and epoxy-based laminate adhesives do not have high gas barrier properties. For packaging materials that require gas barrier properties, polyvinylidene chloride (PVDC) coating layers, polyvinyl alcohol (PVA) coating layers Various gas barrier layers such as an ethylene-vinyl alcohol copolymer (EVOH) film layer, a metaxylylene adipamide film layer, a film layer deposited with alumina or silica, and a sealant layer such as a flexible polymer film layer. It is necessary to bond via an adhesive layer such as an adhesive layer or an anchor coat layer (see Patent Document 5), which increases the manufacturing cost of the laminated film and complicates the laminating process. As a method for solving these problems, an adhesive for gas barrier laminates has been proposed (see Patent Document 6).

  However, the gas barrier laminating adhesive described above may cause the peeling of the adhesive layer on the ink layer and the ink cohesive strength to be reduced when printing is performed on the substrate on which the adhesive is applied. There was a problem that the laminate strength of the film was lowered.

Japanese Patent Laid-Open No. 5-51574 JP-A-9-316422 JP 2000-154365 A WO99 / 60068 pamphlet Japanese Patent Laid-Open No. 10-71664 JP 2002-256208 A

  An object of the present invention is to solve the above problems and provide a gas barrier laminate film having excellent laminate strength even when printing is performed on a substrate.

  As a result of intensive studies to solve the above problems, the present inventors added a silane coupling agent to the ink layer applied to the substrate, and then laminated a sealant film using a gas barrier adhesive, The present inventors have found that a laminated film having gas barrier properties and excellent adhesiveness can be obtained economically and with good workability, and has led to the present invention.

  That is, the present invention is a laminate film in which at least a substrate, an ink layer, an adhesive layer, and a sealant layer are laminated in this order, the ink layer contains a silane coupling agent, and the adhesive layer In the cured epoxy resin obtained by curing the epoxy resin composition, the adhesive that forms the resin is mainly composed of an epoxy resin composition comprising an epoxy resin and an epoxy resin curing agent. The laminate structure is characterized by containing 40% by weight or more of the skeleton structure shown in FIG.

  The laminate film of the present invention is excellent in adhesiveness in addition to gas barrier properties, and is applied to various uses as a non-halogen gas barrier material. In addition, the laminate film has an excellent laminate strength even when printing is performed on the substrate, and is useful.

  The laminate film in the present invention is a laminate in which at least a substrate, an ink layer, an adhesive layer, and a sealant layer are laminated in this order. When making a laminate film, the base material layer is used on the outer surface of the bag and the sealant layer is used on the inner surface of the bag.

Examples of the substrate in the present invention include polyester films such as polyethylene terephthalate and polybutylene terephthalate; polyamide films such as nylon 6, nylon 6,6, and metaxylene adipamide (N-MXD6); Degradable film; polyolefin film such as low density polyethylene, high density polyethylene, linear low density polyethylene, polypropylene; polyacrylonitrile film; poly (meth) acrylic film; polystyrene film; polycarbonate film; ethylene-vinyl alcohol Copolymer (EVOH) film; polyvinyl alcohol film; paper such as carton; metal foil such as aluminum and copper. Also, films obtained by coating various materials used as these substrates with various polymers such as polyvinylidene chloride (PVDC) resin, polyvinyl alcohol resin, ethylene-vinyl acetate copolymer saponified resin, acrylic resin; A film in which various inorganic compounds or metals such as silica, alumina, and aluminum are vapor-deposited; a film in which an inorganic filler is dispersed; a film having an oxygen scavenging function, and the like can be used. Moreover, an inorganic filler can be disperse | distributed also about the various polymers to coat. Examples of inorganic fillers include silica, alumina, mica, talc, aluminum flakes, and glass flakes. Layered silicates such as montmorillonite are preferred, and dispersion methods thereof include, for example, extrusion kneading and mixing into resin solutions. A conventionally known method such as a dispersion method can be used. Examples of methods for imparting oxygen scavenging functions include hindered phenols, vitamin C, vitamin E, organic phosphorus compounds, gallic acid, pyrogallol and other low molecular organic compounds that react with oxygen, cobalt, manganese, nickel, iron And a method of using a composition containing a transition metal compound such as copper at least in part.
The thickness of these film materials is about 10 to 300 μm, preferably about 10 to 100 μm, and in the case of a plastic film, it may be stretched in a uniaxial or biaxial direction.

  In the present invention, the film material such as polyolefin and polyester is laminated (for example, between the adhesive layer and the sealant layer) as a layer other than the base material, ink layer, adhesive layer, and sealant layer. May be. When laminating various materials, a plurality of adhesive layers may be provided. Moreover, you may use together adhesive agents other than the adhesive agent in this invention.

  The ink layer in the present invention is composed of organic pigments such as azo, phthalocyanine, and isoindolinone; inorganic pigments such as titanium dioxide, carbon black, and calcium carbonate; polyurethane resins, polyester resins, polyurethane urea resins, and acrylic modified urethane resins. Polyurethane resins such as acrylic-modified urethane urea resins; vinyl chloride-vinyl acetate copolymer resins; rosin resins such as rosin-modified maleic resins; polyamide resins; chlorinated olefin resins such as chlorinated polypropylene resins; Binders such as nitrocellulose resins and rubber resins; have been used for printing layers on conventional polymer films formed from solvents such as water, methanol, 2-propanol, ethyl acetate, methyl ethyl ketone, and toluene. Depending on the ink It is made. For the formation of the ink layer, general printing equipment that has been used for printing on a conventional polymer film such as a gravure printing machine, a flexographic printing machine, and an offset printing machine can be similarly applied.

  The ink for forming the ink layer may be a one-component curing type or a two-component curing type, but in the case of a two-component curing type, it is desirable to use polyisocyanate as a curing agent. Specific examples include aromatic polyisocyanates such as toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI), or aliphatic polyisocyanates such as hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), and xylene diisocyanate (XDI). It is done.

  Further, the ink layer in the present invention contains a silane coupling agent. As the silane coupling agent, commercially available ones can be used, among which N- (2-aminoethyl) available from Chisso Corporation, Toray Dow Corning Corporation, Shin-Etsu Chemical Co., Ltd., etc. ) -3-Aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N, N'-bis [ Amino-based silane coupling agents such as 3-trimethoxysilyl] propyl] ethylenediamine, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltri Epoxy silane coupling agents such as methoxysilane and 3-glycidoxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane It is desirable to have an organic functional group such as a methacryloxy silane coupling agent such as, a mercapto silane coupling agent such as 3-mercaptopropyltrimethoxysilane, and an isocyanate silane coupling agent such as 3-isocyanatopropyltriethoxysilane. . Of these, isocyanate-based silane coupling agents are preferred. When adding these, the range of 0.01-10 weight part is preferable with respect to 100 weight part of solid content total amounts, such as an ink pigment and resin.

  The ink diluted with the solvent (coating liquid) can be diluted at a concentration such that the Zahn cup (No. 3) viscosity is in the range of 5 to 30 seconds (25 ° C.). If the Zahn cup (No. 3) viscosity is less than 5 seconds, the ink is not sufficiently applied to the object to be coated, which causes contamination of the roll. If the Zahn cup (No. 3) viscosity exceeds 30 seconds, the ink does not sufficiently transfer to the roll, and it becomes difficult to form a uniform ink layer. For example, in a gravure printing machine, the Zahn cup (No. 3) viscosity is preferably 10 to 20 seconds (25 ° C.) during use.

Further, the solvent drying temperature after applying the ink may be various from 20 ° C. to 140 ° C., but the temperature is close to the boiling point of the solvent and does not affect the object to be coated. If the drying temperature is less than 20 ° C., the solvent remains in the film, causing poor adhesion and odor. On the other hand, when the drying temperature exceeds 140 ° C., it becomes difficult to obtain a film having a good appearance due to softening of the polymer film. For example, when applying ink to a stretched polypropylene film, 40 to 120 degreeC is desirable.
The ink layer on the substrate may be continuous (full-surface printing) or intermittent (partial printing).

The adhesive forming the adhesive layer of the present invention is mainly composed of an epoxy resin composition composed of an epoxy resin and an epoxy resin curing agent, and the above-mentioned epoxy resin cured product obtained by curing the epoxy resin composition ( 1) The skeletal structure represented by the formula is characterized by containing 40% by weight or more, preferably 45% by weight or more, more preferably 50% by weight or more. When the skeleton structure of the formula (1) is contained at a high level in the cured epoxy resin, a high gas barrier property is exhibited. According to the present invention, an oxygen permeability coefficient of 1 at 23 ° C. and 60% RH is. An adhesive layer having an oxygen barrier property of 0 ml · mm / m ² · day · MPa or less can also be obtained. Below, the epoxy resin and epoxy resin hardening | curing agent which are the main components of an epoxy resin composition are demonstrated.

The epoxy resin in the present invention may be any of an aliphatic compound, an alicyclic compound, an aromatic compound, or a heterocyclic compound. However, in consideration of the expression of high gas barrier properties, the aromatic moiety is located in the molecule. Is preferable, and an epoxy resin including the skeleton structure of the above formula (1) in the molecule is more preferable. Specific examples include an epoxy resin having a glycidylamino group derived from metaxylylenediamine, an epoxy resin having a glycidylamino group derived from 1,3-bis (aminomethyl) cyclohexane, and a glycidyl derived from diaminodiphenylmethane. Epoxy resin having amino group, epoxy resin having glycidylamino group and / or glycidyloxy group derived from paraaminophenol, epoxy resin having glycidyloxy group derived from bisphenol A, glycidyloxy group derived from bisphenol F Epoxy resin having a glycidyloxy group derived from phenol novolac, an epoxy resin having a glycidyloxy group derived from resorcinol, etc. It is. Among them, an epoxy resin having a glycidylamino group derived from metaxylylenediamine, an epoxy resin having a glycidylamino group derived from 1,3-bis (aminomethyl) cyclohexane, and a glycidyloxy group derived from bisphenol F Epoxy resins and epoxy resins having glycidyloxy groups derived from resorcinol are preferred.
Furthermore, it is more preferable to use an epoxy resin having a glycidyloxy group derived from bisphenol F or an epoxy resin having a glycidylamino group derived from metaxylylenediamine as a main component. It is particularly preferable to use an epoxy resin having a glycidylamino group as a main component.

  Moreover, in order to improve various performances such as flexibility, impact resistance, and moist heat resistance, the above-mentioned various epoxy resins can be mixed and used at an appropriate ratio.

  The epoxy resin is obtained by reaction of alcohols, phenols and amines with epihalohydrin. For example, an epoxy resin having a glycidylamino group derived from metaxylylenediamine can be obtained by adding epichlorohydrin to metaxylylenediamine. Since metaxylylenediamine has four amino hydrogens, mono-, di-, tri- and tetraglycidyl compounds are formed. The number of glycidyl groups can be changed by changing the reaction ratio between metaxylylenediamine and epichlorohydrin. For example, an epoxy resin having mainly four glycidyl groups can be obtained by addition reaction of about 4 times mole of epichlorohydrin to metaxylylenediamine.

The epoxy resin is an excess of epihalohydrin with respect to various alcohols, phenols and amines in the presence of an alkali such as sodium hydroxide, 20 to 140 ° C., preferably 50 to 120 ° C. in the case of alcohols and phenols, amine In the case of the class, it is synthesized by reacting at a temperature of 20 to 70 ° C. and separating the by-produced alkali halide.
The number average molecular weight of the produced epoxy resin varies depending on the molar ratio of epihalohydrin to various alcohols, phenols and amines, but is about 80 to 4000, preferably about 200 to 1000, preferably about 200 to 500. It is more preferable.

The epoxy resin curing agent in the present invention may be any of an aliphatic compound, an alicyclic compound, an aromatic compound, or a heterocyclic compound, such as polyamines, phenols, acid anhydrides, or carboxylic acids. Any commonly used epoxy resin curing agent can be used. These epoxy resin curing agents can be selected according to the use application of the laminate film and the required performance in the application.
Specifically, examples of polyamines include aliphatic amines such as ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; aliphatic amines having an aromatic ring such as metaxylylenediamine and paraxylylenediamine; 1,3- Examples thereof include alicyclic amines such as bis (aminomethyl) cyclohexane, isophoronediamine and norbornanediamine; and aromatic amines such as diaminodiphenylmethane and metaphenylenediamine. In addition, epoxy resins using these as raw materials, modification reaction products of polyamines and monoglycidyl compounds, modification reaction products of polyamines and epichlorohydrin, modification reactions of polyamines and alkylene oxides having 2 to 4 carbon atoms. Products, amide oligomers obtained by reaction of polyamines with polyfunctional compounds having at least one acyl group, polyamines, polyfunctional compounds having at least one acyl group, and monovalent carboxylic acids and / or Amide oligomers obtained by reaction with the derivatives can also be used as epoxy resin curing agents.

Examples of phenols include polyphenols such as catechol, resorcinol and hydroquinone, and resole type phenol resins.
Acid anhydrides or carboxylic acids include aliphatic acid anhydrides such as dodecenyl succinic anhydride and polyadipic anhydride, and alicyclic acid anhydrides such as (methyl) tetrahydrophthalic anhydride and (methyl) hexahydrophthalic anhydride. Aromatic acid anhydrides such as phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and carboxylic acids thereof can be used.

In consideration of the expression of high gas barrier properties, an epoxy resin curing agent containing an aromatic moiety in the molecule is preferred, and an epoxy resin curing agent containing the skeleton structure of the above formula (1) in the molecule is more preferred.
Specifically, metaxylylenediamine or paraxylylenediamine, reaction products with epoxy resins or monoglycidyl compounds using these as raw materials, reaction products with alkylene oxides having 2 to 4 carbon atoms, epichlorohydrin Reaction products with these polyamines, reaction products with polyfunctional compounds having at least one acyl group, which can form amide group sites by reaction with these polyamines to form oligomers, reaction with these polyamines It is more preferable to use a reaction product of a polyfunctional compound having at least one acyl group and a monovalent carboxylic acid and / or a derivative thereof, which can form an amide group site to form an oligomer.

In consideration of high gas barrier properties and good adhesion to ink layers, sealant layers, and other layers, the following reaction products (A) and (B) or (A) as epoxy resin curing agents It is particularly preferred to use the reaction products of (B) and (C).
(A) Metaxylylenediamine or paraxylylenediamine
(B) A polyfunctional compound having at least one acyl group capable of forming an amide group site by reaction with a polyamine to form an oligomer
(C) C1-C8 monovalent carboxylic acid and / or derivative thereof

  Examples of the polyfunctional compound having at least one acyl group that can form an amide group site by reaction with the (B) polyamine to form an oligomer include acrylic acid, methacrylic acid, maleic acid, fumaric acid, succinic acid, Carboxylic acids such as malic acid, tartaric acid, adipic acid, isophthalic acid, terephthalic acid, pyromellitic acid, trimellitic acid and their derivatives such as esters, amides, acid anhydrides, acid chlorides, etc., especially acrylic acid Methacrylic acid and derivatives thereof are preferred.

  Examples of the monovalent carboxylic acid having 1 to 8 carbon atoms of (C) include formic acid, acetic acid, propionic acid, butyric acid, lactic acid, glycolic acid, benzoic acid and the like, and derivatives thereof such as esters. Amides, acid anhydrides, acid chlorides and the like can also be used. These may be used in combination with the above polyfunctional compound and reacted with a polyamine (metaxylylenediamine or paraxylylenediamine). The amide group site introduced by the reaction has a high cohesive force, and the presence of the amide group site in a high proportion in the epoxy resin curing agent results in higher oxygen barrier properties and better resistance to other film materials. Adhesive strength is obtained.

The reaction molar ratio of (A) and (B) or (A), (B) and (C) is the reactive functional group contained in (B) with respect to the number of amino groups contained in (A). Or the ratio of the total number of reactive functional groups contained in (B) and (C) to the number of amino groups contained in (A) ranges from 0.3 to 0.97. preferable. When the ratio is less than 0.3, a sufficient amount of amide groups are not generated in the epoxy resin curing agent, and a high level of gas barrier properties and adhesiveness are not exhibited. Moreover, the ratio of the volatile molecule which remains in the epoxy resin curing agent is increased, which causes odor generation from the obtained cured product. Moreover, since the ratio of the hydroxyl group produced | generated by reaction of an epoxy group and an amino group in the hardening reaction material becomes high, it becomes a factor by which oxygen barrier property in a high humidity environment falls remarkably. On the other hand, in the range higher than 0.97, the amount of amino groups reacting with the epoxy resin is reduced, and excellent impact resistance and heat resistance are not exhibited, and the solubility in various organic solvents or water is lowered.
When particularly considering the high gas barrier property, high adhesion, suppression of odor generation, and high oxygen barrier property in a high humidity environment of the obtained cured product, the molar ratio of the polyfunctional compound to the polyamine component is 0.6. A range of ˜0.97 is more preferable. In consideration of the expression of a higher level of adhesiveness, it is preferable that the epoxy resin curing agent in the present invention contains at least 6% by weight of an amide group based on the total weight of the curing agent.

  The laminate film produced using the adhesive in the present invention preferably has a laminate strength (initial adhesive strength) at a peeling rate of 300 mm / min immediately after lamination (before aging) of 30 g / 15 mm or more, 40 g / It is more preferably 15 mm or more, and particularly preferably 50 g / 15 mm or more. When the initial adhesive force is not sufficient, problems such as tunneling of the laminate film and winding deviation when winding the film occur.

  When considering the expression of high initial adhesive strength, the ratio of the number of reactive functional groups contained in (B) to the number of amino groups contained in component (A), and contained in component (A) The ratio of the total number of reactive functional groups contained in (B) and (C) to the number of amino groups is 0.6 to 0.97, preferably 0.8 to 0.97, particularly preferably 0.8. It is preferable to use an oligomer having a high average molecular weight obtained as a range of 85 to 0.97 as an epoxy resin curing agent. More preferable epoxy resin curing agent is a reaction product of metaxylylenediamine (component (A)) and at least one compound (component (B)) selected from acrylic acid, methacrylic acid and / or derivatives thereof. The ratio of the number of reactive functional groups contained in at least one compound selected from acrylic acid, methacrylic acid and / or derivatives thereof to amino groups contained in metaxylylenediamine is 0.8 to A range of 0.97 is preferred.

The adhesive used in the present invention includes an epoxy composition comprising the above epoxy resin and an epoxy resin curing agent. The content of the epoxy composition in the adhesive is preferably at least 51% by weight (including 100%). The blending ratio of the epoxy resin and the epoxy resin curing agent in the epoxy composition may generally be a standard blending range when obtaining an epoxy resin cured product by reaction of the epoxy resin and the epoxy resin curing agent. Specifically, it mix | blends so that ratio (active hydrogen / epoxy ratio) of the number of active hydrogens in an epoxy resin hardening | curing agent with respect to the number of epoxy groups in an epoxy resin may be in the range of 0.5-5.0. If the range is less than 0.5, the remaining unreacted epoxy group causes the gas barrier property of the resulting cured product to decrease, and if it is greater than 5.0, the remaining unreacted amino group results in the resulting cured product. It becomes a cause of lowering the heat and heat resistance. When the gas barrier property and heat-and-moisture resistance of the obtained cured product are particularly considered, the range of 0.8 to 3.0 is more preferable, and the range of 0.8 to 2.0 is more preferable.
In addition, when considering the expression of high oxygen barrier properties in a high humidity environment of the obtained cured product, the ratio of the number of active hydrogens in the epoxy resin curing agent to the number of epoxy groups in the epoxy resin is 0.8. A range of ~ 1.4 is preferred.

  If necessary, the adhesive may include a thermosetting resin such as polyurethane resin, polyacrylic resin, polyurea resin, etc., as long as the effects of the present invention are not impaired. You may mix 0.1 to 49 weight% with respect to the total weight of an agent, and the following similarly.

  In order to improve the wettability to the surface of various base materials or ink layers, an adhesive such as silicon or an acrylic compound may be added to the adhesive as necessary. Suitable wetting agents include BYK325, BYK331, BYK333, BYK350, BYK345, BYK347, BYK348, BYK361N, BYK380N, BYK381 available from Big Chemie. When adding these, the range of 0.01 to 2.0 weight% is preferable with respect to the epoxy composition whole quantity.

  A tackifier such as a xylene resin, a terpene resin, a phenol resin, or a rosin resin may be added to the adhesive as necessary in order to improve the adhesiveness to various substrates or ink layers immediately after coating. When adding these, the range of 0.01 to 5.0 weight% is preferable with respect to the epoxy composition whole quantity.

  In order to improve the performance of the adhesive layer such as gas barrier properties, impact resistance, heat resistance, etc., inorganic fillers such as silica, alumina, mica, talc, aluminum flakes and glass flakes are added to the adhesive. Also good. In consideration of the transparency of the film, the inorganic filler is preferably flat. When adding these, the range of 0.01-10.0 weight% is preferable with respect to the epoxy composition whole quantity.

  Moreover, you may add the compound etc. which have an oxygen capture | acquisition function to an adhesive agent as needed. Examples of compounds having an oxygen scavenging function include hindered phenols, vitamin C, vitamin E, organophosphorus compounds, gallic acid, pyrogallol, and other low molecular organic compounds that react with oxygen, cobalt, manganese, nickel, iron, Examples include transition metal compounds such as copper.

  Furthermore, in order to improve the adhesion of the adhesive layer to various substrates, ink layers, sealant layers, and other layers, coupling agents such as silane coupling agents and titanium coupling agents are added to the resin composition. You may do it. As the coupling agent, commercially available ones can be used, among which N- (2-aminoethyl) which can be obtained from Chisso Corporation, Toray Dow Corning Corporation, Shin-Etsu Chemical Co., Ltd., etc. -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N, N'-bis [3 -Trimethoxysilyl] propyl] amino silane coupling agents such as ethylenediamine, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxy Epoxy silane coupling agents such as silane, 3-glycidoxypropyltriethoxysilane, and 3-methacryloxypropyltrimethoxysilane Tacryloxy silane coupling agent, mercapto silane coupling agent such as 3-mercaptopropyltrimethoxysilane, isocyanate silane coupling agent such as 3-isocyanatopropyltriethoxysilane, SH- manufactured by Toray Dow Corning Co., Ltd. Organics capable of reacting with the gas barrier resin composition of the present invention, such as aminosilane coupling agents such as 6026 and Z-6050, amino group-containing alkoxysilanes such as KP-390 and KC-223 manufactured by Shin-Etsu Chemical Co., Ltd. Those having a functional group are desirable. When adding these, the range of 0.01-5 weight part is preferable with respect to 100 weight part of total amounts of an epoxy resin and an epoxy resin hardening | curing agent.

  The adhesive layer formed from the above adhesive exhibits high gas barrier properties in a wide range from low humidity conditions to high humidity conditions in addition to suitable adhesion performance to various substrates, ink layers, sealant layers, and other layers. . Therefore, the laminate film of the present invention includes a PVDC coat layer, a polyvinyl alcohol (PVA) coat layer, an ethylene-vinyl alcohol copolymer (EVOH) film layer, a metaxylylene adipamide (N-MXD6) film layer, alumina, It has a very high gas barrier property without using a commonly used gas barrier material such as a film layer deposited with silica or the like. Gas barrier properties can be further improved by bonding these conventional gas barrier materials to the sealant layer via the adhesive.

  Also, ethylene-vinyl alcohol copolymer (EVOH) film, polyvinyl alcohol (PVA) film, polyvinyl alcohol coat film, polyvinyl alcohol coat film in which inorganic filler is dispersed, metaxylene adipamide (N-MXD6) film Such gas barrier films have a drawback that the gas barrier properties are lowered under high humidity conditions. However, when these gas barrier films are bonded to each other through the adhesive, this disadvantage can be solved.

Furthermore, since the adhesive layer formed from the adhesive is excellent in toughness and heat-and-moisture resistance, a gas barrier laminate film excellent in impact resistance, boiling resistance, retort resistance, and the like can be obtained.
It is preferable to use a flexible polymer as the material for the sealant layer. Considering the expression of good heat sealability, polyolefins such as low density polyethylene, linear low density polyethylene, polypropylene, and ethylene-vinyl acetate copolymers are more preferable. The thickness of the sealant layer is preferably about 10 to 300 μm, more preferably about 10 to 100 μm. The surface of the sealant layer may be subjected to surface treatment such as flame treatment or corona discharge treatment.

Hereinafter, the manufacturing method of the laminate film of this invention is demonstrated.
When forming an ink layer on a base material, it is preferable to perform surface treatments such as flame treatment and corona discharge treatment on the surface of the base material as necessary so that defects such as film breakage and repellency do not occur. The ink layer is formed by a general printing facility that has been used for printing on a conventional polymer film such as a gravure printing machine, a flexographic printing machine, and an offset printing machine. The ink layer may be continuous (full surface printing) or intermittent (partial printing). The thickness of the ink layer is preferably about 0.01 to 10 μm, more preferably about 0.1 to 5 μm.

  The adhesive layer can be formed by a known laminating method such as dry lamination, non-solvent lamination, or extrusion lamination.

  The adhesive is applied as a coating liquid having an epoxy composition concentration of about 5% by weight diluted with an organic solvent and / or water to the base film on which the ink layer has been applied without dilution. The concentration and temperature of the epoxy composition are selected according to the kind and amount of the epoxy resin, the epoxy resin curing agent, the laminating method, and the like so that the cured epoxy resin can be obtained.

Any solvent that dissolves the adhesive can be used as the organic solvent. For example, water-insoluble solvents such as toluene, xylene, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone; 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol, 1-methoxy-2 -Glycol ethers such as propanol, 1-ethoxy-2-propanol, 1-propoxy-2-propanol; alcohols such as methanol, ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol; acetaldehyde, propionaldehyde Aldehydes such as: aprotic polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, and N-methylpyrrolidone.

  The adhesive is diluted with a solvent so that the Zahn cup (No. 3) viscosity of the coating solution is in the range of 5 to 30 seconds (25 ° C.). When the Zahn cup (No. 3) viscosity is 5 seconds or less, the coating solution is not sufficiently applied to the substrate film on which the ink layer has been applied, which causes contamination of the roll. Further, when the Zahn cup (No. 3) viscosity is 30 seconds or more, the adhesive does not sufficiently transfer to the roll, and it becomes difficult to form a uniform adhesive layer. For example, in dry lamination, the Zahn cup (No. 3) viscosity is preferably 10 to 20 seconds (25 ° C.) during use.

  In order to suppress foaming of the coating liquid when preparing the coating liquid in the present invention, an antifoaming agent such as silicon or an acrylic compound may be added to the coating liquid. Suitable antifoaming agents include BYK019, BYK052, BYK065, BYK066N, BYK067N, BYK070, BYK080, and the like available from Big Chemie, with BYK065 being particularly preferred. Moreover, when adding these antifoamers, the range of 0.01 weight%-3.0 weight% is preferable with respect to the epoxy composition whole quantity in a coating liquid, 0.02 weight%-2.0 weight% % Is more preferable.

  Moreover, when using a solvent, the solvent removal temperature after apply | coating a coating liquid is the range which is the range of 20-140 degreeC, and is close to the boiling point of a solvent, and has no influence on a coating object. When the removal temperature is 20 ° C. or higher, the amount of solvent remaining in the laminate film is small, and adhesion failure and generation of odor can be avoided. When the removal temperature is 140 ° C. or lower, a laminate film having a good appearance can be obtained without softening the polymer film. For example, when a stretched polypropylene film is used as the substrate, 40 to 120 ° C. is preferable.

  The coating methods for applying adhesives include general printing equipment, roll coating, spray coating, and air knife that have been used for printing on conventional polymer films such as gravure printing machines, flexographic printing machines, and offset printing machines. Any of the painting types such as coating, dipping, brushing, die coating, etc. can be used. A printing machine or roll coating is preferred. For example, a gravure printing machine or roll coater and equipment similar to those used for applying gravure ink to a polymer film can be applied.

Next, specific operations in each laminating method will be described.
In the case of the dry laminating method, the coating liquid is applied to a base film on which an ink layer has been applied by a roll such as a gravure roll, then the solvent is removed, and a sealant layer is immediately applied to the surface by a nip roll, preferably 20 to 120. A laminate film can be obtained by bonding at a temperature of, preferably 40 to 100 ° C. The solvent for the coating solution is preferably a solvent containing an alcohol having 3 or less carbon atoms, which has a good solubility in an adhesive and a relatively low boiling point, and is selected from the group consisting of methanol, ethanol, isopropanol, and n-propanol. The solvent which has 1 or more types of selected as a main component is illustrated. In addition, a mixture containing a carbonyl solvent having an ester group, ketone group, or aldehyde group functional group that has the effect of delaying the reaction between the epoxy resin and the epoxy resin curing agent and suppressing the rapid thickening of the coating solution. A liquid is preferred. Examples of the carbonyl solvent include one or more compounds selected from the group consisting of ethyl acetate, acetone, methyl ethyl ketone, acetaldehyde, and propionaldehyde having a relatively low boiling point. In order to obtain a laminate film with a small amount of residual solvent, the content of the carbonyl solvent is preferably 20% by weight or less in the total solvent. If residual solvent content of the laminate film is large, it will cause bad smell, residual solvent content is preferably 7 mg / m ² or less. When it is more than 7 mg / m ² , it may cause a strange odor from the film. To prevent the occurrence of odors more reliably, more preferably 5 mg / ^{m 2} or less, 3 mg / ^{m 2} or less is more preferred.

  After laminating the sealant layer, it is desirable to complete the curing reaction by aging at a temperature of 20 to 60 ° C. for a certain time as necessary. By this aging, a cured epoxy resin is formed with a sufficient reaction rate, and high gas barrier properties are exhibited. When the aging is 20 ° C. or less or without aging, the reaction rate of the epoxy resin composition is low, and sufficient gas barrier properties and adhesive strength cannot be obtained. Aging at 60 ° C. or higher may cause problems such as blocking of the base material containing polyamide or the sealant layer and elution of additives.

  In the dry laminating method, a laminate film can be produced by forming each layer in the reverse order. That is, the adhesive is applied not only to the base film to which the ink layer is applied, but also to a polyethylene film that forms a sealant layer, a polyolefin film such as a polypropylene film, or an ethylene-vinyl acetate copolymer film, After forming an adhesive layer by drying and then forming an ink layer, a laminate film can be produced by laminating substrates such as stretched polypropylene, polyamide-based film, and polyethylene terephthalate film.

  When the base material coated with the base film coated with the ink layer is bonded by a nip roll, the nip roll temperature is preferably 20 to 120 ° C, more preferably 40 to 100 ° C.

  In the case of the non-solvent laminating method, an adhesive that has been heated to about 40 ° C. to 100 ° C. in advance on the base film on which the ink layer has been applied is applied by a roll such as a gravure roll heated to 40 ° C. to 120 ° C. Thereafter, a laminate film can be obtained by immediately laminating a sealant layer on the surface. In this case as well, as in the case of the dry laminating method, it is desirable to perform aging for a predetermined time after the lamination as necessary.

In the case of the extrusion laminating method, the adhesive coating liquid is applied to the base film on which the ink layer has been applied using a roll such as a gravure roll, the solvent is removed at 20 to 140 ° C., the curing reaction is performed, and then the extruder is used. A laminated film can be obtained by laminating the melted sealant layer material.
The above laminating method and other general laminating methods can be combined as necessary.

  The final thickness of the adhesive layer in the laminate film after applying, drying, laminating and heat-treating the adhesive in the present invention is preferably 0.1 to 100 μm, more preferably 0.5 to 10 μm. Is. Within the above range, an adhesive layer having a uniform thickness can be formed without deteriorating gas barrier properties and adhesiveness.

  The laminate film of the present invention has excellent laminate strength. The laminate strength measured with a peel strength of 300 mm / min varies depending on the material of the base material and the sealant layer. For example, when the base material is stretched polypropylene, 80 g / 15 mm or more is preferable, and 100 g / 15 mm or more is more preferable. Particularly preferably, it is 120 g / 15 mm or more. When the base material is stretched nylon or polyethylene terephthalate, if the sealant layer is low density polyethylene, it is preferably 600 g / 15 mm or more, more preferably 700 g / 15 mm or more, and particularly preferably 800 g / 15 mm or more. If it is unstretched polypropylene, 300 g / 15 mm or more is preferable, 400 g / 15 mm or more is more preferable, Especially preferably, it is 500 g / 15 mm or more.

  The laminate film of the present invention can be used as a multilayer packaging material for the purpose of protecting foods and pharmaceuticals. You may change the layer structure of a multilayer packaging material according to the kind of preserve | saved goods, use environment, and a use form. For example, the laminate film of the present invention can be used as a multilayer packaging material as it is, and an optional layer such as an oxygen absorbing layer, a thermoplastic resin film layer, a paper layer, or a metal foil layer can be used as needed. The film can be further laminated. The arbitrary layer may be laminated using the adhesive in the present invention, or may be laminated using another adhesive or an anchor coat agent.

  In the laminated film of the present invention, the two sealant layers are made to face each other by folding or overlapping after or without forming the above-mentioned optional layer, and then the peripheral edge is heat sealed to form a packaging bag. Can do. Heat seal forms include, for example, side seals, two-sided seals, three-sided seals, envelope stickers, joint seals (pillow seals), flat bottom seals, square bottom seals, gusset seals, etc. Chosen according to In addition, for example, a self-supporting packaging bag (standing pouch) can be used. Examples of the heat seal method include known methods such as bar seal, rotary roll seal, belt seal, impulse seal, high frequency seal, and ultrasonic seal.

  After filling the packaging bag with the contents, the opening can be heat sealed to produce a packaged product using the laminate film of the present invention. The contents to be preserved include rice crackers, bean confectionery, nuts, biscuits and cookies, wafer confectionery, marshmallows, pies, semi-baked cakes, candy, snack confectionery and other confectionery, bread, snack noodles, instant noodles, dried noodles, pasta , Aseptic packaging rice, elephant rice, rice porridge, packaging rice cake, cereal foods, staples, pickles, boiled beans, natto, miso, frozen tofu, tofu, licked rice, konjac, edible wild vegetables, jams, peanut cream, salads, frozen Agricultural processed products such as vegetables, potato processed products, hams, bacon, sausages, chicken processed products, livestock processed products such as corned beef, fish hams and sausages, fish paste products, kamaboko, paste, boiled bonito, salted fish, Seafood products such as smoked salmon and mentaiko, peaches, tangerines, pineapples, apples, pears, Cooking of fruit such as cherries, vegetables such as corn, asparagus, mushrooms, onions, carrots, radishes, potatoes, hamburger, meatballs, marine fries, gyoza, croquettes, etc. Examples include dairy products such as finished food, butter, margarine, cheese, cream, instant creamy powder, and infant formula, liquid seasonings, retort curry, and pet food. It can also be used as a packaging material for tobacco, disposable body warmers, pharmaceuticals, cosmetics and the like.

  Examples of the present invention are introduced below, but the present invention is not limited to these examples.

Each measurement and evaluation was performed by the following method.
(1) Oxygen permeability coefficient (ml · mm / (m ² · day · MPa))
The oxygen permeability coefficient of the adhesive layer was measured under the conditions of 23 ° C. and 60% relative humidity using an oxygen permeability measuring device (OX-TRAN 10 / 50A, manufactured by Modern Control).
(2) Laminate strength (g / 15mm)
Using the method specified in JISK-6854, the laminate strength of the laminate film was measured by a T-type peel test at a peel rate of 300 mm / min.
(3) Heat seal strength (kg / 15mm)
The sealant layers of the two laminate films are heat sealed at 2 kg / cm ² , 1 second, 150 ° C. using a thermal gradient heat seal machine (Type HG-100) manufactured by Toyo Seiki Seisakusho Co., Ltd. The strength of the heat seal part was measured by the same method.
(4) Residual solvent amount (mg / m ² )
200 laminated film pieces (25 cm × 1 cm) were placed in an Erlenmeyer flask and heated at 80 ° C. for 30 minutes, and then the solvent concentration of air in the flask was analyzed by GC. From the result, the residual solvent amount per 1 m ^{2 of} the laminate film was calculated.

<Production Example 1>
Epoxy resin curing agent A
A reaction vessel was charged with 1 mole of metaxylylenediamine. The temperature was raised to 60 ° C. under a nitrogen stream, and 0.93 mol of methyl acrylate was added dropwise over 1 hour. After completion of the dropwise addition, the mixture was stirred at 120 ° C. for 1 hour, and further heated to 160 ° C. in 3 hours while distilling off generated methanol. It cooled to 100 degreeC, methanol was added so that solid content concentration might be 70 weight%, and the epoxy resin hardening | curing agent A diluted with methanol was obtained. The content (based on solid content) of the amide group in the epoxy resin curing agent A was 21% by weight.

<Production Example 2>
Epoxy resin curing agent B
A reaction vessel was charged with 1 mole of metaxylylenediamine. The temperature was raised to 60 ° C. under a nitrogen stream, and 0.93 mol of methyl acrylate was added dropwise over 1 hour. After completion of the dropwise addition, the mixture was stirred at 120 ° C. for 1 hour, and further heated to 160 ° C. in 3 hours while distilling off generated methanol. It cooled to 100 degreeC, ethanol was added so that solid content concentration might be 70 weight%, and the epoxy resin hardening | curing agent B diluted with ethanol was obtained. The content (based on solid content) of the amide group in the epoxy resin curing agent B was 21% by weight.

<Example 1>
50 parts by weight of an epoxy resin having a glycidylamino group derived from metaxylylenediamine (Mitsubishi Gas Chemical Co., Ltd .; TETRAD-X), 104 parts by weight of epoxy resin curing agent A, 258 parts by weight of methanol, acetic acid Ethyl was blended to 29 parts by weight and mixed well (methanol / ethyl acetate = 9/1, solid content concentration: 35% by weight) with a silicon-based antifoaming agent (by Big Chemie). 0.05 parts by weight of BYK065) was added and stirred well to obtain an adhesive having a Zahn cup (No. 3) viscosity of 14 seconds (25 ° C.).
Daibe Seika Kogyo Co., Ltd. NT-HIRAMIC 701R White (T) / NT-HIRAMIC Hardener (Hardener added 5 parts to 100 parts of white ink), Shin-Etsu Chemical Co., Ltd. KBE- 9007 (3-isocyanatopropyltriethoxysilane) was added in an amount of 5 parts based on the solid content of the ink to obtain a white ink. White ink is printed on the entire upper surface of a stretched 6-nylon film (Harden N1102 manufactured by Toyobo Co., Ltd.) with a thickness of 15 μm, and an adhesive is 100 lines / cm, and a 100 μm depth gravure roll is printed on the printed surface side of the film. The adhesive layer was formed by applying and drying in a drying oven at 60 ° C. (near the entrance) to 90 ° C. (near the exit). A linear polyethylene film having a thickness of 40 μm (TUX MC-S manufactured by Tosero Co., Ltd.) was bonded to the adhesive layer by a nip roll heated to 70 ° C., wound at a winding speed of 130 m / min, and rolled. Was aged at 40 ° C. for 4 days to obtain a laminate film. The resulting laminated film was evaluated for gas barrier properties and laminate strength. The results are shown in Table 1. The content of the skeleton structure of the formula (1) in the adhesive layer (cured epoxy resin) was 62.0% by weight.

<Example 2>
A laminate film was produced in the same manner as in Example 1, except that a stretched polyethylene terephthalate film (Toyobo Co., Ltd. Ester film E5100) having a thickness of 12 μm was used instead of the stretched 6-nylon film having a thickness of 15 μm. The results are shown in Table 1.

<Example 3>
A laminate film was produced in the same manner as in Example 1 except that a stretched polypropylene film having a thickness of 20 μm (Pyrene P2161 manufactured by Toyobo Co., Ltd.) was used instead of the stretched 6-nylon film having a thickness of 15 μm. The results are shown in Table 1.

<Example 4>
Add 3 parts by weight of S330 manufactured by Chisso Corporation to the adhesive mixture and stir well. Instead of the stretched 6-nylon film having a thickness of 15 μm, a silica-deposited polyester film having a thickness of 12 μm (Tech Barrier manufactured by Mitsubishi Plastics, Inc.) A laminate film was produced in the same manner as in Example 1 except that L) was used. The results are shown in Table 1.

<Example 5>
50 parts by weight of epoxy resin having a glycidylamino group derived from metaxylylenediamine (Mitsubishi Gas Chemical Co., Ltd .; TETRAD-X), 104 parts by weight of epoxy resin curing agent B, 258 parts by weight of ethanol, acetic acid Ethyl was blended to 29 parts by weight and mixed well (ethanol / ethyl acetate = 9/1, solid content concentration: 35% by weight) with a silicon-based antifoaming agent (by Big Chemie) 0.05% by weight of BYK065) was added, stirred well, and a laminate film was prepared in the same manner as in Example 1 except that an adhesive having a Zahn cup (No. 3) viscosity of 15 seconds (25 ° C.) was used. . The results are shown in Table 1.

<Comparative Example 1>
A laminate film was produced in the same manner as in Example 1 except that no silane coupling agent was added to the ink. The results are shown in Table 1.

<Comparative example 2>
A laminate film was produced in the same manner as in Example 2 except that no silane coupling agent was added to the ink. The results are shown in Table 1.

<Comparative Example 3>
A laminate film was produced in the same manner as in Example 3 except that no silane coupling agent was added to the ink. The results are shown in Table 1.

<Comparative example 4>
A laminate film was produced in the same manner as in Example 4 except that no silane coupling agent was added to the ink. The results are shown in Table 1.

Claims (4)

A laminate film in which at least a substrate, an ink layer, an adhesive layer, and a sealant layer are laminated in this order, and the ink layer contains a silane coupling agent and forms an adhesive layer. An epoxy resin composition comprising an epoxy resin and an epoxy resin curing agent as a main component, and a skeleton structure represented by the formula (1) in the cured epoxy resin obtained by curing the epoxy resin composition A laminate film containing 40% by weight or more.

  The laminate film according to claim 1, wherein the silane coupling agent is an isocyanate-based silane coupling agent. The laminate film according to claim 1, wherein the adhesive layer has an oxygen barrier property of an oxygen permeability coefficient of 1.0 ml · mm / m ² · day · MPa (23 ° C., 60% RH) or less.   The laminate film according to claim 1, wherein the laminate film is produced by a dry lamination method.