JP2013252617A - Method of manufacturing laminated thin film, and laminated thin film with masking film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a laminated thin film which can restrain wrinkles from appearing when the films with a thickness of 25 μm or less are stacked and which has a good appearance, and the like.SOLUTION: In a method of manufacturing a laminated thin film 10, the laminated thin film is manufactured through steps including: a first thin film sticking step of forming a pressure sensitive adhesive layer on one surface of a masking film and sticking thin films A with a thickness of 25 μm or less together via the pressure sensitive adhesive layer; an adhesive layer forming step of forming an adhesive layer on the thin film; a drying step of drying the adhesive layer; a second thin film sticking step of sticking a thin film B with a thickness of 25 μm or less together on the adhesive layer after drying; and a peeling and removal step of peeling and removing the masking film. The adhesion of the pressure sensitive adhesive layer is in the range of 5-250 N/m, and the tensile strength of the masking film is in the range of 20-300 MPa.

Description

  TECHNICAL FIELD The present invention relates to a method for producing a laminated thin film film and a laminated thin film film with a masking film, and more particularly to a method for producing a laminated thin film used for displays of various display devices and a laminated thin film with a masking film. .

  In the display field of various display devices (see, for example, Patent Document 1), further downsizing is progressing depending on the application, and accordingly, a functional film for display, for example, a laminated gas barrier film, is laminated. Thinning as a structure is required. In the conventional laminated gas barrier film, if the counterpart film to be laminated has a thickness of 25 μm or more, the rigidity of the film is high.

  However, as described above, when trying to laminate films with a thickness of less than 25 μm in order to achieve thinning as a laminated structure of a laminated gas barrier film, the film has insufficient rigidity and wrinkles occur during production. And it becomes easy to cause trouble. In particular, when using a solvent-based adhesive, drying at a high temperature is required to evaporate the solvent. For this reason, wrinkles such as shrinkage due to drying are likely to occur. When the gas barrier film is used for a display in such a state, a defect due to the wrinkles may occur on the display screen, and the appearance is impaired.

JP 2009-274395 A

  In view of the above, an object of the present invention is to solve the above conventional problems. That is, the present invention is a method for producing a laminated thin film having a good appearance and capable of suppressing generation of wrinkles when laminating films having a thickness of less than 25 μm, and laminating with a masking film. An object of the present invention is to provide a mold thin film.

  As a result of intensive studies to achieve the above object, the present inventors provided a thin film on a specific masking film when laminating (bonding) films having a thickness of less than 25 μm. In the state, when other thin film was bonded together, it was found that the generation of wrinkles was suppressed and a laminated thin film having a good appearance could be produced, and the present invention was conceived. That is, the present invention is as follows.

[1] A first thin film film laminating step in which a thin film A having a thickness of less than 25 μm is bonded to a masking film in which an adhesive layer is formed on at least one side of a base material via the adhesive layer;
An adhesive layer forming step of forming an adhesive layer on the thin film A;
A drying step of drying the adhesive layer;
A second thin film film laminating step for laminating a thin film B having a thickness of less than 25 μm on the adhesive layer after drying;
A method for producing a laminated thin film composed of a thin film A, an adhesive layer and a thin film B through a peeling and removing step for peeling and removing the masking film,
The manufacturing method of the laminated thin film film whose adhesive force of the said adhesive layer is 5-250 N / m, and whose tensile strength of the said masking film is 20-300 MPa.
[2] The method for producing a laminated thin film according to [1], wherein the adhesive forming the adhesive layer is a thermosetting adhesive.
[3] The method for producing a laminated thin film according to [1] or [2], wherein the laminated thin film is a gas barrier film for display.

[4] A thin film A having a thickness of less than 25 μm, an adhesive layer, and a thin film having a thickness of less than 25 μm are formed on a masking film having a pressure-sensitive adhesive layer formed on at least one side of a substrate. B is laminated,
A laminated thin film with a masking film, wherein the pressure-sensitive adhesive layer has an adhesive strength of 5 to 250 N / m and the masking film has a tensile strength of 20 to 300 MPa.
[5] The laminated thin film with a masking film according to the above [4], wherein the adhesive forming the adhesive layer is a thermosetting adhesive.

According to the present invention, when laminating films having a thickness of less than 25 μm, it is possible to suppress generation of wrinkles, and a method for producing a laminated thin film having a good appearance, and lamination with a masking film A mold thin film can be provided.
Therefore, it is possible to incorporate the manufacturing method of the laminated thin film of the present invention into the display manufacturing process of various display devices. Moreover, the laminated thin film with a masking film of the present invention can also be applied as a member for a functional film for display (for example, a gas barrier film) when manufacturing displays of various display devices.

It is explanatory drawing for demonstrating the evaluation method for evaluating the generation amount of a wrinkle of an Example.

Hereafter, the manufacturing method of the lamination type thin film of this invention is divided into each process, and is demonstrated.
(First thin film bonding process)
In the first thin film film bonding step, a thin film A having a thickness of less than 25 μm is bonded to a masking film in which an adhesive layer is formed on at least one side of the substrate via the adhesive layer.

The base material of the masking film is preferably a film having excellent heat resistance. For example, polyethylene terephthalate (PET) film, polycarbonate film, polyolefin (PO) film, aramid film, polyethylene naphthalate film, polyphenylene sulfide film, aromatic An aromatic polysulfone film, a polyetherimide film, a polyarylate film, a polyetheretherketone film, and the like can be given.
Of these, a polyethylene terephthalate film is preferred because of its excellent balance of heat resistance, chemical resistance, economy, and the like.
Although there is no restriction | limiting in particular about the thickness of this masking film, It is preferable that it is 12-50 micrometers, and it is more preferable that it is 25-40 micrometers. By being 12-50 micrometers, favorable workability | operativity is implement | achieved and cost can be held down.

Moreover, when producing a laminated thin film, it is necessary to consider the rigidity of the entire film, but in practice it is convenient to consider the rigidity with the tensile strength of the masking film.
The tensile strength of the masking film is 20 to 300 MPa, preferably 50 to 300 MPa, and more preferably 200 to 300 MPa. When the tensile strength is 20 to 300 MPa, damage due to tension or heat during processing can be reduced.

The tensile strength can be measured, for example, as follows.
First, a strip-shaped test piece having a width of 10 mm is prepared, and the film is pulled at a speed of 50 mm / min. The strength when the film is broken is measured and defined as the tensile strength.

The pressure-sensitive adhesive layer formed on one surface of the substrate masking film has an adhesive strength of 5 to 250 N / m, preferably 30 to 250 μm, and more preferably 70 to 250 μm. When the adhesive strength is less than 5 N / m, peeling occurs during the treatment process, causing defects. When the adhesive strength exceeds 250 N / m, when the masking film is peeled off after the thin film B described later is bonded, it becomes difficult to peel off and the productivity is lowered, or the components of the adhesive layer remain in the thin film A. And cause defects.
The adhesive strength of the pressure-sensitive adhesive layer can be measured by the method described later.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer may be any of an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, etc., but preferably an acrylic polymer, particularly a (meth) acrylic acid ester-based polymer. Is an acrylic adhesive mainly composed of
The acrylic polymer can be obtained, for example, by radical polymerization of a monomer mixture containing a (meth) acrylic acid alkyl ester and a functional group-containing monomer by a conventional method using a polymerization initiator.
Examples of the (meth) acrylic acid alkyl ester include acrylics having about 1 to 12 carbon atoms in the alkyl group such as methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, butyl methacrylate, 2-ethylhexyl methacrylate and the like. Examples include acid alkyl esters and methacrylic acid alkyl esters. These alkyl (meth) acrylates can be used alone or in combination of two or more.
In addition, you may replace a part of this (meth) acrylic-acid alkylester with other copolymerizable monomers, such as styrene and vinyl acetate, as needed.
The functional group-containing monomer contributes as a component for improving the activity and wettability with respect to the adherend surface, and also acts as a crosslinking point to give a good result in improving the cohesive force.
Examples of such monomers include carboxyl group or acid anhydride group-containing monomers such as acrylic acid, methacrylic acid, and maleic anhydride; hydroxyl groups such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxyethyl vinyl ether. Containing monomers; amino group-containing monomers such as N, N-dimethylaminoethyl acrylate and N, N-dimethylaminoethyl methacrylate; amide group-containing monomers such as acrylic amide and methacrylamide, and other epoxy groups , A polymer having a phosphine group, a sulfone group and the like can also be used.

The pressure-sensitive adhesive layer can be formed by a known method such as gravure coating, roll coating, bar coating, die coating, and knife coating. The thickness (after drying) of the pressure-sensitive adhesive layer is preferably 5 to 40 μm, and more preferably 10 to 30 μm.
When the thickness is 5 to 40 μm, uniform coating is easily performed, and an increase in cost can be suppressed.

On the adhesive layer of the masking film, a thin film A having a thickness of less than 25 μm is bonded by a known method.
Since the pressure-sensitive adhesive layer has an adhesive strength of 5 to 250 N / m as described above, the thin film A is bonded to such an extent that it can be peeled off from the pressure-sensitive adhesive layer of the masking film.

The thin film A is preferably a base film (preferably a base film having gas barrier properties) or a gas barrier film having at least one inorganic film on at least one surface of the base film.
As the base film, a plastic film is preferable, and as the raw material, any resin that can be used for ordinary packaging materials can be used without any particular limitation. Specifically, polyolefins such as homopolymers or copolymers such as ethylene, propylene and butene, amorphous polyolefins such as cyclic polyolefin, polyesters such as polyethylene terephthalate and polyethylene-2,6-naphthalate, nylon 6, nylon 66, polyamide resin such as nylon 12, copolymer nylon, ethylene-vinyl acetate copolymer partial hydrolyzate (EVOH), polyimide, polyetherimide, polysulfone, polyethersulfone, polyetheretherketone, polycarbonate, polyvinyl Examples include butyral, polyarylate, fluororesin, acrylic resin, and biodegradable resin. Among these, polyesters, polyamides, and polyolefins are preferable from the viewpoints of film properties and cost. Of these, polyesters such as polyethylene terephthalate and polyethylene-2,6-naphthalate are particularly preferred from the viewpoint of film properties.

  The base film is a known additive such as an antistatic agent, a light blocking agent, an ultraviolet absorber, a plasticizer, a lubricant, a filler, a colorant, a stabilizer, a lubricant, a crosslinking agent, an antiblocking agent, An antioxidant etc. can be contained.

The plastic film as the substrate film is formed by using the above raw materials, but when used as a substrate, it may be unstretched or stretched. Further, it may be a single layer or a multilayer. Such a base film can be produced by a conventionally known method. For example, the raw material is melted by an extruder, extruded by an annular die or a T die, and rapidly cooled to be substantially amorphous and not oriented. An unstretched film can be manufactured. Moreover, by using a multilayer die, it is possible to produce a resin type 1 single layer film, a type 1 multilayer film, and a variety of multilayer films.
The unstretched film is subjected to a known method such as uniaxial stretching, tenter sequential biaxial stretching, tenter simultaneous biaxial stretching, tubular simultaneous biaxial stretching, or the like. A film stretched in a uniaxial direction or a biaxial direction can be produced by stretching in a direction (horizontal axis) perpendicular thereto. Although a draw ratio can be set arbitrarily, it is preferable that 150 degreeC heat shrink rate is 0.01 to 5%, Furthermore, it is preferable that it is 0.01 to 2%.
Among these, from the viewpoint of film properties, a biaxially stretched polyethylene terephthalate film, a biaxially stretched polyethylene naphthalate film, and a coextruded biaxially stretched film of polyethylene terephthalate and polyethylene naphthalate are preferable.

The thickness of the base film is usually selected in the range of 5 to 500 μm, preferably 10 to 200 μm, depending on its use from the viewpoint of mechanical strength, flexibility, transparency, etc. as the base material of the gas barrier film. Also, a sheet having a large thickness is included. Moreover, there is no restriction | limiting in particular about the width | variety and length of a film, It can select according to a use suitably.
Moreover, in order to improve the applicability | paintability to the base film of the anchor coating agent mentioned later, and adhesiveness, you may perform surface treatments, such as a normal chemical treatment and electrical discharge treatment, before application | coating of an anchor coating agent.

It is preferable to apply an anchor coating agent to the base film in order to improve adhesion with the inorganic film. Anchor coating agents include polyester resins, isocyanate resins, urethane resins, acrylic resins, vinyl alcohol resins such as polyvinyl alcohol resins and ethylene vinyl alcohol resins, vinyl butyral resins, resins, nitrocellulose resins, and oxazoline groups. Resins, carbodiimide group-containing resins, methylene group-containing resins, epoxy group-containing resins, styrene resins, silicone resins, and the like can be used alone or in combination of two or more.
It also contains silane coupling agents, titanium coupling agents, alkyl titanates, light blockers, ultraviolet absorbers, stabilizers, lubricants, antiblocking agents, antioxidants, etc. A polymerized product can be used.

  As a method for forming the anchor coat layer, a known coating method is appropriately adopted. For example, any method such as a coating method using a reverse roll coater, a gravure coater, a rod coater, an air doctor coater, a spray or the like can be used. Alternatively, the film may be immersed in a resin solution. After coating, the solvent can be evaporated using a known drying method such as hot drying such as hot air drying or hot roll drying at a temperature of about 80 to 200 ° C. or infrared drying. Moreover, in order to improve water resistance and durability, the crosslinking process by electron beam irradiation can also be performed.

Further, the formation of the anchor coat layer may be a method performed in the middle of the substrate film production line (inline) or a method performed after the substrate film is manufactured (offline).
The thickness of the anchor coat layer is about 0.005 to 5 μm, and preferably 0.01 to 1 μm. If the thickness is 5 μm or less, the slipperiness is good, there is almost no peeling from the base film due to the internal stress of the anchor coat layer itself, and if the thickness is 0.005 μm or more, the thickness is uniform. It is possible to keep the thickness.
Further, since the surface of the base film is flattened by anchor coating, the particles forming the inorganic film are densely deposited and can be easily formed to have a uniform thickness, so that a high gas barrier property can be obtained.

As a method for forming the inorganic film, any method such as a vapor deposition method and a coating method can be used, but the vapor deposition method is preferable in that a uniform thin film having a high gas barrier property can be obtained. This vapor deposition method includes methods such as physical vapor deposition (PVD) and chemical vapor deposition (CVD). Examples of physical vapor deposition include vacuum deposition, ion plating, sputtering, etc. Chemical vapor deposition includes plasma CVD using plasma, and a catalyst that catalytically decomposes a source gas using a heated catalyst body. Examples include chemical vapor deposition (Cat-CVD).
Examples of the inorganic substance constituting the inorganic film formed on at least one surface of the base film include silicon, aluminum, magnesium, zinc, tin, nickel, titanium, diamond-like carbon, and oxides, carbides, and nitrides thereof. Or a mixture thereof, preferably silicon oxide, silicon nitride, silicon oxynitride, silicon oxynitride carbide, aluminum oxide, diamond-like carbon. In particular, silicon oxide, silicon nitride, silicon oxynitride, silicon oxynitride carbide, and aluminum oxide are preferable in that high gas barrier properties can be stably maintained.

  The source gas that can be used for chemical vapor deposition is preferably composed of at least one gas. For example, in the formation of a silicon compound thin film, as a second source gas with respect to the first source gas containing silicon, It is preferable to use a rare gas such as ammonia, nitrogen, oxygen, hydrogen or argon. Examples of the first source gas containing silicon include monosilane, tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane. Ethoxysilane, diphenyldiethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane, decyltrimethoxysilane, trifluoropropyltrimethoxysilane, hexamethyldisiloxane, hexamethyldisilazane, etc. alone or 2 Can be used in combination. The source gas may be liquid or gas at room temperature, and the liquid source can be vaporized by a source vaporizer and supplied into the apparatus. In the catalytic chemical vapor deposition method, monosilane gas is preferable from the viewpoint of deterioration of the heated catalyst body, reactivity, and reaction rate.

  The thickness of the inorganic film is preferably about 0.1 to 500 nm, and more preferably 0.5 to 40 nm. If it is in the said range, sufficient gas barrier property will be acquired, and it will be excellent also in transparency, without generating a crack and peeling in an inorganic film.

From the viewpoint of improving gas barrier properties, it is effective to form a multilayer inorganic film. Even if the thin film formed by any one manufacturing method is piled up, for example, vacuum deposition, ion plating, sputtering, chemical vapor deposition, etc., the multilayering of the inorganic film and the order of each layer are two or more different types. The thin films formed by the manufacturing method may be alternately stacked.
The number of layers of the inorganic film is not limited as long as the required gas barrier property is obtained. From the viewpoint of manufacturing cost and film formation stability, about 1 to 10 layers are preferable, and 1 to 5 layers are more preferable.

When the inorganic films described above are stacked in multiple layers, a resin layer may be provided between the inorganic films. By having the resin layer, effects such as improved adhesion between inorganic films, dense particle deposition, and void filling between particles can be obtained.
The components and the forming method of the resin layer can be the same as those in the above-described “anchor coat layer”.

In order to improve the adhesion between inorganic films, the resin layer preferably contains a silane coupling agent and a titanium coupling agent.
Examples of the silane coupling agent include epoxy group-containing silane cups such as β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxylane, and γ-glycidoxypropyltrimethoxysilane. Ring agent, γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyljetoxylan, N-β (aminoethyl) γ-aminopropyltrimethoxylane, N-β (aminoethyl) γ- Examples include amino group-containing silane coupling agents such as aminopropyltriethoxylane, and mixtures thereof. Preferably, the silane coupling agent includes γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltrimethoxysilane. These may be used alone or in combination. Moreover, it is preferable that it is 0.1-80 mass% with respect to resin which forms a resin layer from an adhesive point, and it is more preferable that it is 1-50 mass%.

  When energy beam crosslinking is performed, there is no limitation as long as it is a monomer containing a functional group that is crosslinked by ultraviolet rays or electron beams, but it is preferable to use a monomer having an acryloyl group, a methacryloyl group, or an oxirane group. For example, epoxy (meth) acrylate, urethane (meth) acrylate, isocyanuric acid (meth) acrylate, pentaerythritol (meth) acrylate, trimethylolpropane (meth) acrylate, ethylene glycol (meth) acrylate, polyester (meth) acrylate, etc. Among these, it is preferable that the main component is a polymer obtained by crosslinking a monomer having a bifunctional or higher functional acryloyl group or methacryloyl group. These monomers having a bifunctional or higher functional acryloyl group or methacryloyl group may be used as a mixture of two or more kinds, or as a mixture of monofunctional (meth) acrylates. From the viewpoint of curing speed, a monomer having an acryloyl group is most preferable.

When the resin layer is formed by vapor deposition polymerization, the resin layer is formed by polymerization and curing using a monomer and an oligomer that can be polymerized by vacuum deposition. For example, a resin component composed of a polymerizable monomer, oligomer or mixture thereof such as acrylic is vaporized and spray-coated on the surface of an inorganic film under vacuum, and polymerized and cured by heating and / or irradiation with ultraviolet rays or electron beams. Get. In the case of curing by ultraviolet irradiation, an acrylic resin coating agent mixed with a photopolymerization initiator is used in addition to a resin component comprising an acrylic monomer, oligomer, or a mixture thereof. Examples of photopolymerization initiators include benzoyl ethers, benzophenones, xanthones, acetophenone derivatives, etc., which are molecularly bonded to the above monomers, oligomers, etc. in order to prevent volatilization from the resin layer after curing. Are preferably used in an amount of 0.01 to 10% by weight, more preferably 0.1 to 2% by weight based on the monomer, oligomer or mixture thereof.
The molecular weight of the monomer or oligomer is preferably 10,000 or less, more preferably 2000 or less, and particularly preferably 1000 or less. The viscosity is preferably 500 cPs or less at room temperature, more preferably 100 cPs or less.

  The thickness of the resin layer is about 0.5 nm to 0.1 μm, preferably 0.5 to 20 nm, more preferably 0.5 to 5 nm from the viewpoint of adhesion.

Further, a protective layer may be provided to protect the uppermost layer of the inorganic film. Examples of the resin for forming the protective layer include polyester resins, urethane resins, acrylic resins, vinyl alcohol resins such as polyvinyl alcohol resins and ethylene vinyl alcohol resins, ethylene / unsaturated carboxylic acid copolymers, vinyls. Ester resin, nitrocellulose resin, silicone resin, epoxy resin, styrene resin, isocyanate group-containing resin, carbodiimide group-containing resin, alkoxyl group-containing resin, oxazoline group-containing resin, etc. alone or in combination Can be used. Among these, water-soluble resins are preferable from the viewpoint of improving gas barrier properties of the inorganic layer, and at least one selected from polyvinyl alcohol resins, ethylene vinyl alcohol resins, and ethylene / unsaturated carboxylic acid copolymers is preferable. .
In addition, the protective layer contains one or more inorganic particles selected from particulate inorganic fillers and layered inorganic fillers, such as inorganic sols such as silica sol and alumina sol, in order to improve barrier properties, abrasion resistance, and slipperiness. can do.

  The thickness of the protective layer is preferably 0.05 to 10 μm, more preferably 0.1 to 3 μm, from the viewpoints of printability and processability. A known coating method is appropriately adopted as the formation method. For example, any method such as a reverse roll coater, a gravure coater, a rod coater, an air doctor coater, and a coating method using a spray can be used. After application, moisture can be evaporated using a known drying method such as hot drying such as hot air drying or hot roll drying at a temperature of about 80 to 200 ° C. or infrared drying. Moreover, in order to improve water resistance and durability, the crosslinking process by electron beam irradiation can also be performed.

(Adhesive layer forming process)
In the adhesive layer forming step, an adhesive layer is formed on the thin film A.
As the adhesive constituting the adhesive layer, a thermosetting adhesive, an active energy ray curable adhesive and a water-based adhesive can be used. Of these, thermosetting adhesives are preferred.

Examples of thermosetting adhesives include adhesives composed of polyester resins, urethane resins, acrylic resins, ether resins, phenol resins, furan resins, urea resins, melamine resins, and epoxy resins. Agents and the like.
Examples of the active energy ray-curable adhesive include an adhesive containing urethane resin, polyester resin, and the like as components.

  Among the above, an adhesive containing at least one selected from a urethane resin, an epoxy resin, a polyester resin, and an acrylic resin as a component is preferable. Moreover, you may use thermoplastic resins, such as a polyimide, polyether imide, polyether amide imide, without being limited to a thermosetting resin.

The resins used for the adhesive can be used alone or in combination of two or more.
As the above-mentioned adhesive, among them, an adhesive that forms an adhesive layer having gas barrier properties and an adhesive that does not easily generate bubbles in the adhesive layer after production of a gas barrier film laminate are preferable.

An example of an adhesive that hardly generates bubbles is an epoxy curing system.
Moreover, the adhesive agent which can be used conveniently as an adhesive agent which forms the adhesive bond layer which has gas-barrier property is as follows. That is, it is preferable that the adhesive layer has a gas barrier property because it has a large number of aromatic rings such as a metaxylenediamine skeleton, a paraxylenediamine skeleton, and a bisphenol skeleton.
Furthermore, a curing system using an epoxy resin is preferable in that it is difficult to generate bubbles in the adhesive layer after forming the gas barrier film laminate.

The epoxy resin of the curable adhesive using the epoxy resin having the advantage of having gas barrier properties and hardly generating bubbles is as follows.
That is, an epoxy resin having a glycidylamine moiety derived from metaxylylenediamine, an epoxy resin having a glycidylamine moiety derived from 1,3-bis (aminomethyl) cyclohexane, and a glycidylamine moiety derived from diaminodiphenylmethane. Epoxy resin having glycidylamine moiety derived from paraaminophenol, epoxy resin having glycidyl ether moiety derived from bisphenol A, epoxy resin having glycidyl ether moiety derived from bisphenol F, derived from phenol novolac And an epoxy resin having a glycidyl ether moiety derived from resorcinol, and the like.

  Among these, an epoxy resin having a glycidylamine moiety derived from metaxylylenediamine and / or an epoxy resin having a glycidyl ether moiety derived from bisphenol F is preferable from the viewpoint of gas barrier properties.

  The curable adhesive usually uses a curing agent together with the resin component as the main agent, but the curing agent used together with the epoxy resin is preferably an epoxy resin curing agent. For example, the following (A) and The reaction product of (B) or the reaction product of (A), (B), and (C) is mentioned.

(A) a polyfunctional compound having at least one acyl group that can form an amide group site by reaction with metaxylylenediamine or paraxylylenediamine (B) polyamine to form an oligomer (C) having 1 to 1 carbon atoms 8 monovalent carboxylic acids and / or derivatives thereof

Examples of the polyfunctional compound (B) include carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, succinic acid, malic acid, tartaric acid, adipic acid, isophthalic acid, terephthalic acid, pyromellitic acid, and trimellitic acid. Acids and derivatives thereof such as esters, amides, acid anhydrides, acid chlorides and the like can be mentioned, and acrylic acid, methacrylic acid and derivatives thereof are particularly preferable. In addition, the (C) monovalent carboxylic acid having 1 to 8 carbon atoms and / or a derivative thereof is a monovalent carboxylic acid such as formic acid, acetic acid, propionic acid, butyric acid, lactic acid, glycolic acid, benzoic acid, or a derivative thereof. Examples include esters, amides, acid anhydrides, acid chlorides, and the like.
About the mixture ratio of an epoxy resin and an epoxy resin hardening | curing agent, you may be a standard compounding range in the case of producing an epoxy resin hardened material by reaction of an epoxy resin and an epoxy resin hardening | curing agent generally. Specifically, 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 in the range of 0.5 to 5.0, preferably 0.8 to 3.0.

  In addition, as an aqueous adhesive, the main component is an anionic aqueous polyurethane emulsion whose main skeleton is a polyolefin-based polyol obtained by reacting a polyolefin-based polyol and a polyisocyanate, and other components include amines and water-soluble high-boiling organics. What contains a solvent etc. can also be used. Such a water-based adhesive is effective for bonding a polyolefin resin material or a polyester resin material.

  In addition, the above-mentioned water-based adhesive may be a polyether polyurethane emulsion, a polyester polyurethane emulsion, a polycarbonate polyurethane emulsion, a polyacrylate emulsion, an ethylene / vinyl acetate copolymer emulsion, or a styrene / butadiene copolymer, if necessary. It can also contain 1 type, or 2 or more types chosen from aqueous plastic emulsions, such as an emulsion and a polyvinyl acetate emulsion.

In addition to adjusting the adhesive composition by resin formulation, the viscosity of the adhesive can be adjusted by adjusting the amount of residual solvent depending on the temperature and time when applying the adhesive varnish, and in the case of thermosetting resins, the semi-cured state is controlled Can be adjusted. The adhesive can also be adjusted by adding inorganic particles such as crystalline silica, amorphous silica, aluminum hydroxide, alumina, aluminum nitride, boron nitride, antimony trioxide and organic particles such as silicone powder. is there.
Although the said inorganic particle and organic particle | grains may be used by 1 type, they can also be used in combination of 2 or more type.
As the inorganic particles, silica particles are preferably used from the viewpoint of versatility and stability.
From the viewpoint of hot water resistance and cohesive fracture resistance, the average particle size of the inorganic particles or organic particles is preferably 0.005 to 50 μm, more preferably 0.01 to 20 μm, and still more preferably 0.05 to 10 μm. Further, the content of the inorganic particles and / or organic particles in the adhesive is preferably 0.01 to 30% by mass, and 0.05 to 10% by mass from the viewpoint of defoaming property and adhesive strength. It is more preferable.
In addition to the above, the adhesive may appropriately contain additives such as a curing accelerator, a coupling agent, an inorganic ion adsorbent, and a polymerization initiator as necessary.

  The thickness of the adhesive layer is preferably 0.2 to 30 μm, and preferably 0.5 to 10 μm from the viewpoint of adhesive strength and workability when formed by applying and drying the adhesive. More preferred. Moreover, when using a film-form adhesive (henceforth "adhesive film"), from the point of workability, it is preferable that the thickness is 1-100 micrometers, and is 5-50 micrometers. It is more preferable.

The adhesive film preferably has a low elastic modulus in order to reduce the thermal stress resulting from the difference in thermal expansion coefficient of the gas barrier film, and the storage elastic modulus when measured using a dynamic viscoelasticity measuring device. Is 10 to 2000 MPa at 25 ° C., and preferably 3 to 50 MPa at 260 ° C.
Examples of the adhesive film include an epoxy resin, an epoxy group-containing acrylic copolymer, a phenol resin, an epoxy resin curing agent, and a semi-cured epoxy thermosetting resin composed of an epoxy resin fat curing agent. The thing which consists of at least 1 type chosen from is mentioned.

(Drying process)
In the drying step, the formed adhesive layer is dried. As a drying means, a known drying furnace (drying apparatus) can be used. The drying temperature is preferably adjusted as appropriate in consideration of the adhesive or dilution solvent to be used, the volume and air volume of the drying furnace, and the like.

(Second thin film bonding process)
In the second thin film film bonding step, a thin film B having a thickness of less than 25 μm is bonded onto the dried adhesive layer.
The thin film B can be composed of the materials mentioned for the thin film A, and may be the same as or different from the thin film A. The laminating means for laminating the thin film B is not particularly limited, and known laminating means can be applied. When the thin film B has an inorganic film layer, the inorganic film surface is laminated toward the adhesive layer side.

Through the steps up to the second thin film film bonding step, a thin film A having a thickness of less than 25 μm, an adhesive layer, and a thin film B having a thickness of less than 25 μm are formed via the pressure-sensitive adhesive layer of the masking film. Thus, the laminated thin film with a masking film of the present invention is produced.
The laminated thin film with a masking film of the present invention has a good appearance with suppressed generation of wrinkles. Moreover, since the pressure-sensitive adhesive layer has an appropriate pressure-sensitive adhesive force, the peelability is good and the appearance is not impaired during peeling.

(Peeling removal process)
In the peeling and removing step, the masking film is peeled and removed from the thin film A. That is, the masking film is peeled and removed from the laminated thin film with a masking film. The means for peeling and removing is not particularly limited, and known means can be applied.

Through the steps as described above, a laminated thin film composed of the thin film A, the adhesive layer, and the thin film B is manufactured.
When the laminated thin film of the present invention is used as a gas barrier film for a display, the structure of the base film or inorganic film in the thin film A and the thin film B is appropriately changed, for example, 1.0 (g / ( m ² · day)) The following water vapor transmission rate may be used.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples. The evaluation methods of various characteristics in each example are shown below.

(Tensile strength of masking film)
Test piece: The masking film was cut into a strip shape having a width of 10 mm to prepare a test piece.
Measurement: The masking film was pulled at a speed of 50 mm / min with a tensile tester, and the strength when the masking film was broken was measured to obtain the tensile strength.
(Adhesive strength of the adhesive layer)
Test piece: A sample in which various adhesives were applied to a 25 μm thick PET film at a thickness of 25 μm was cut into a 25 mm wide strip to prepare a test piece.
Substrate: SUS304 steel plate polished with No. 280 water-resistant abrasive paper was used.
Affixing conditions: The test piece and the adherend were pressed with a 2 kg rubber roller.
Measurement: After pressure bonding, the test piece was peeled off from the adherend in the 180 ° direction at a speed of 300 mm / min, and the strength at that time was measured.

(Wrinkle generation amount)
Considering actual use, the following tests were conducted.
That is, as shown in FIG. 1, each of the produced laminated thin film films 10 with a masking film (without a masking film in Comparative Example 1) is stretched by rolls 12A and 12B, and one end thereof is in the direction of the arrow. After adding a load (800 g / 670 mm width), the amount of wrinkles that can be visually observed was examined.
The case where the amount of wrinkles generated was 3 or less was marked with ◯, the case where it was 4 to 8 was marked with △, and the number of wrinkles was marked with x.

(Appearance after peeling)
The appearance of the laminated thin film after peeling the masking film from the laminated thin film with masking film was visually observed.
In the appearance, the case where creases, wrinkles, and adhesive residue occurred was evaluated as x, and the case where it did not occur was evaluated as ◯.

(Comprehensive judgment)
From each evaluation of the amount of wrinkles generated and the appearance after peeling, a comprehensive judgment was made on each example. When all of the above evaluations were ◯, the comprehensive judgment was also ◯, when the combination of ◯ and △ was combined, the comprehensive judgment was △, and when any of them was x, the comprehensive judgment was x.
It should be noted that if the comprehensive judgment is ◯ or Δ, there is no practical problem, and if it is ◯, it is particularly excellent in practice.

Example 1
A pressure-sensitive adhesive layer (thickness: 25 μm) was formed on one surface of a 25 μm-thick PET film (trade name: T100 manufactured by Mitsubishi Plastics) to prepare a masking film.
The pressure-sensitive adhesive forming the pressure-sensitive adhesive layer was SK Dyne 2147 manufactured by Soken Chemical Co., Ltd., and TD-75 and A-50 were used as curing agents, and the mixing ratio was 1: 0.0004: 0.0006. .
A PET film having a thickness of 12 μm was bonded as a thin film A through the formed pressure-sensitive adhesive layer (first thin film film bonding step).

An adhesive layer (thickness after drying: 5 μm) was formed on the thin film A (adhesive layer forming step).
In addition, 50 weight parts of epoxy resins having a glycidylamine moiety derived from metaxylylenediamine (manufactured by Mitsubishi Gas Chemical Co., Ltd .; TETRAD-X) and the following epoxy resin curing are used for the adhesive forming the adhesive layer. A methanol / ethyl acetate = 1/1 solution (solid content concentration: 30% by weight) containing 89 parts by weight of agent A was prepared, and 0.02 part by weight of an acrylic wetting agent (by BYK Chemie; BYK381) was prepared there. In addition, a well-stirred adhesive was used.

  Epoxy resin curing agent A: 1 mol of metaxylylenediamine was charged into a reaction vessel. The temperature was raised to 60 ° C. under a nitrogen stream, and 0.67 mol of methyl acrylate was added dropwise over 1 hour. After completion of dropping, the mixture was stirred at 120 ° C. for 1 hour, and further heated up to 180 ° C. in 3 hours while distilling off generated methanol. It cooled to 100 degreeC and the predetermined amount methanol was added so that solid content concentration might be 70 weight%, and the epoxy resin hardening | curing agent A was obtained.

Next, after forming an adhesive layer, it was transferred to a drying furnace at 80 ° C. and dried (drying step).
After drying, a PET film having a thickness of 12 μm was bonded as a thin film B on the adhesive layer (second thin film film bonding step). Thereby, the lamination type thin film film with a masking film was manufactured.
After the thin film B was bonded, the masking film was peeled off to produce a laminated thin film composed of the thin film A, the adhesive layer, and the thin film B.

  The amount of wrinkles generated in the laminated thin film and the appearance after peeling off the masking film were evaluated by the method described above. The said evaluation result is shown in following Table 1 with the result of the adhesive strength of an adhesive layer, and the tensile strength of a masking film.

(Example 2)
A laminated thin film with a masking film and a laminated thin film were produced in the same manner as in Example 1 except that a PO film (trade name: M-6, manufactured by Tamapoly Co., Ltd.) was used instead of the PET film as the masking film. In the same manner as in Example 1, the amount of wrinkles generated in the laminated thin film with a masking film and the appearance after the masking film was peeled and removed were evaluated. The said evaluation result is shown in following Table 1 with the result of the adhesive strength of an adhesive layer, and the tensile strength of a masking film.

(Comparative Example 1)
A laminated thin film was produced in the same manner as in Example 1 except that no masking film was used. In the same manner as in Example 1, the amount of wrinkles generated in the laminated thin film was evaluated. The evaluation results are shown in Table 1 below.

(Comparative Example 2)
The same as Example 1 except that SK Dyne FP-7 manufactured by Soken Chemical Co., Ltd. was used as the main agent, and L-45 and E-5XM were used as the curing agent (mixing ratio was 1: 0.00185: 0.0005). Thus, a laminated thin film was produced. In the same manner as in Example 1, the amount of wrinkles generated in the laminated thin film with a masking film and the appearance after the masking film was peeled and removed were evaluated. The said evaluation result is shown in following Table 1 with the result of the adhesive strength of an adhesive layer, and the tensile strength of a masking film.

(Comparative Example 3)
Same as Example 2 except that SK Dyne FP-7 manufactured by Soken Chemical Co., Ltd. was used as the main agent, and L-45 and E-5XM were used as the curing agent (mixing ratio was 1: 0.00185: 0.0005). Thus, a laminated thin film with a masking film was produced. In the same manner as in Example 1, the amount of wrinkles generated in the laminated thin film with a masking film and the appearance after the masking film was peeled and removed were evaluated. The said evaluation result is shown in following Table 1 with the result of the adhesive strength of an adhesive layer, and the tensile strength of a masking film.

  Even when films having a thickness of less than 25 μm are laminated, the generation of wrinkles is suppressed and the appearance is also good. Therefore, the laminated thin film produced according to the present invention can be used for a liquid crystal display or an organic EL. It is suitable for display applications of various display devices such as displays.

12A, 12B ... Roll 10 ... Laminated thin film with masking film

Claims (5)

A first thin film film laminating step of laminating a thin film A having a thickness of less than 25 μm through the pressure sensitive adhesive layer on a masking film having a pressure sensitive adhesive layer formed on at least one side of the substrate;
An adhesive layer forming step of forming an adhesive layer on the thin film A;
A drying step of drying the adhesive layer;
A second thin film film laminating step for laminating a thin film B having a thickness of less than 25 μm on the adhesive layer after drying;
A method for producing a laminated thin film composed of a thin film A, an adhesive layer and a thin film B through a peeling and removing step for peeling and removing the masking film,
The manufacturing method of the laminated thin film film whose adhesive force of the said adhesive layer is 5-250 N / m, and whose tensile strength of the said masking film is 20-300 MPa.   The method for producing a laminated thin film according to claim 1, wherein the adhesive forming the adhesive layer is a thermosetting adhesive.   The method for producing a laminated thin film according to claim 1, wherein the laminated thin film is a gas barrier film for display. A thin film A having a thickness of less than 25 μm, an adhesive layer, and a thin film B having a thickness of less than 25 μm are laminated on the masking film having a pressure-sensitive adhesive layer formed on at least one surface of the substrate. Formed,
A laminated thin film with a masking film, wherein the pressure-sensitive adhesive layer has an adhesive strength of 5 to 250 N / m and the masking film has a tensile strength of 20 to 300 MPa.   The laminated thin film film with a masking film according to claim 4, wherein the adhesive forming the adhesive layer is a thermosetting adhesive.

Images