JP2010260975A - Adhesive polyolefin resin laminated film and protective film using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive polyolefin resin laminate film having scarce fisheyes, and excellent in appearance, and a protective film using the same. <P>SOLUTION: The adhesive polyolefin resin laminate film comprises a polyolefin resin film layer whose density of fisheyes having a size not less than 50 μm is not greater than 10 pieces/m<SP>2</SP>, and an adhesive layer. Also there is provided the protective film using the same. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an adhesive polyolefin resin laminated film and a protective film using the same.

  Polyolefin resins are used in a wide range of industrial fields because they are excellent in economic efficiency, mechanical strength, transparency, moldability, hygiene, etc. For example, they are processed into single-layer or multi-layer films, and optical protective films are used. First, it is widely used as a protective film for metal plates, resin plates, automobiles, electronic materials and the like.

  The demand for the quality of the protective film has become stricter year by year, and in particular, the reduction of fish eyes that impair the appearance is required. Here, the fish eye is one of the drawbacks of a resin film that comes from the presence of foreign matter or gel in the film, and its peripheral part looks like a fish's eye when viewed with the naked eye, a polarizing plate, or a microscope.

  In the case of a polyolefin resin film, it is known that the gel which is one of the causes of fish eyes includes an unmelted gel and a crosslinked gel.

  The crosslinked gel is a gel in which a polyolefin resin is three-dimensionally crosslinked and is difficult to be melted by heating and dissolving in a solvent. On the other hand, an unmelted gel is a gel that can be melted or dissolved by heating, and when melt-kneaded by an extruder and extruded from a die or the like, the ratio of retaining the state as an unmelted gel is high. Incurs a decline.

  In particular, polyolefin resins obtained by high-pressure radical polymerization using a Bessel-type reactor or a tubular-type reactor, such as ethylene / vinyl acetate copolymer and low-density polyethylene, often have the above-mentioned unmelted gel and crosslinked gel. Are known. In the high-temperature reactor, hydrogen is radically extracted from the produced polymer and branches are formed. The reason for this is that this branched polymer is exposed to high temperature separators connected to the reactor and high temperature during the pelletization process, causing unmelted gel as aggregates or cross-linking reaction to form cross-linked gel. It is.

  Therefore, as a method for solving this problem, for example, when ethylene is polymerized under specific polymerization conditions in the presence of a radical polymerization initiator, it is proposed that a radical polymerization inhibitor coexists in the reaction system (for example, , See Patent Document 1).

  In addition, a method for removing the cross-linked gel and unmelted gel contained in the resin during molding has been proposed. For example, a gear pump for transporting a high-viscosity resin melt in an extruder, and a method of manufacturing a film by extruding a molten polyethylene resin have been proposed (see, for example, Patent Document 2). ).

  Furthermore, a film obtained by sandwiching a melted film-like polyolefin resin between a cast roll and an endless belt formed in an arc shape along the roll has been proposed (see, for example, Patent Document 3). ).

JP 2003-342307 A JP-A-8-103952 JP-A-8-25460

  However, although the method proposed in Patent Document 1 has a certain effect of reducing fish eyes, its level is insufficient.

  In addition, the methods described in Patent Documents 2 and 3 have not completely solved the problem that a crosslinked gel is generated because the polyolefin resin is exposed to a high temperature. In particular, since the method described in Patent Document 2 uses a sintered filter, it takes a long time to be exposed to a high temperature.

  Then, this invention aims at providing the adhesive polyolefin resin laminated | multilayer film which has few fish eyes, and is excellent in an external appearance, and a protective film using the same.

As a result of intensive studies to solve the above problems, the present inventors have found that a polyolefin resin film layer having a fish eye of 50 μm or more is 10 pieces / m ² or less, and an adhesive polyolefin resin laminated film comprising an adhesive layer, It has been found that the fisheye is few and the appearance is excellent, and the present invention has been completed. That is, the present invention is a polyolefin resin film layer having a fish eye of 50 μm or more and 10 pieces / m ² or less, an adhesive polyolefin resin laminated film having an adhesive layer, and a protective film using the same.

  Hereinafter, the present invention will be described in detail.

The adhesive polyolefin resin laminated film of the present invention has a polyolefin resin film layer having a fish eye of 50 μm or more and 10 pieces / m ² or less, and an adhesive layer.

  The polyolefin resin film used for the polyolefin resin film layer constituting the present invention is not particularly limited in length, width and thickness, and is a planar molded product, and includes tapes and ribbons. The thickness of the polyolefin resin film is preferably 1 to 200 μm, more preferably 5 to 150 μm, and particularly preferably 10 to 100 μm from the viewpoint of easy handling of the film.

Further, 50 [mu] m or more fish eyes of the polyolefin resin film layer constituting the present invention is 10 pieces / m ² or less, even more preferably at 50 [mu] m or more fisheyes 5 / m ² or less, particularly preferably 3 Pieces / m ² or less. When the number of fish eyes of 50 μm or more exceeds 10 / m ² , for example, it cannot be used as a protective film that requires high quality.

  The fish eye here is defined as a region showing an optically non-uniform state in the polyolefin resin film.

  The polyolefin resin in the polyolefin resin film layer constituting the present invention is not limited, and examples thereof include polyethylene, ethylene copolymer, polypropylene, polypropylene copolymer, and chlorinated products of these polyolefin resins. it can. More specifically, examples of the polyethylene include high density polyethylene, medium density polyethylene, low density polyethylene, linear low density polyethylene, and ultra low density polyethylene. Examples of the ethylene copolymer include an ethylene-α-olefin copolymer, an ethylene-vinyl ester copolymer, an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid copolymer, and an ethylene-acrylic acid ester copolymer. And ethylene-methacrylic acid ester copolymer. Specifically, ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene-4 -Methylpentene-1 resin, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol resin, ethylene-propylene copolymer, ethylene-ethyl acrylate copolymer, ethylene- Examples thereof include an ethyl methacrylate copolymer. Examples of the polypropylene-based copolymer include a polypropylene block copolymer and a polypropylene random copolymer. These polyolefin resins can be used alone or in combination.

  Among them, since the polyolefin resin film layer becomes flexible, the polyolefin resin in the polyolefin resin film layer is at least one selected from the group consisting of polyethylene, ethylene-vinyl acetate copolymer, and saponified ethylene-vinyl acetate copolymer. Preferably, it is a kind of polyolefin resin.

When the polyolefin resin film layer is a polyethylene film, the density of the polyolefin resin film is preferably 900 to 965 kg / m ³ from the viewpoint that the obtained film is flexible and easy to handle. When the polyolefin resin film layer is an ethylene-vinyl acetate copolymer film, the density of the polyolefin resin film is preferably 923 to 970 kg / m ³ because the resulting film is flexible and easy to handle. When the polyolefin resin film layer is a saponified film of ethylene-vinyl acetate copolymer, the density of the polyolefin resin film is preferably 923 to 1200 kg / m ³ from the viewpoint that the obtained film is flexible and easy to handle.

  There is no particular limitation on the polymerization method for synthesizing these polyolefin resins, and generally known methods can be used, for example, high pressure radical polymerization method, medium-low pressure polymerization method, solution polymerization method, slurry polymerization method, etc. Can be mentioned.

  Moreover, there is no restriction | limiting in particular in the catalyst used for superposition | polymerization, For example, a peroxide type catalyst, a Ziegler-Natta catalyst, a metallocene catalyst etc. are mentioned.

The molecular weight of the polyolefin resin in the polyolefin resin film layer constituting the present invention is not limited as long as the polyolefin resin dissolves in the solvent, but the film strength is maintained and the fluidity of the polymer solution is maintained to be a thin film. Therefore, the weight average molecular weight ( _Mw ) in terms of linear polyethylene is preferably 10,000 to 1,000,000, more preferably 20,000 to 700,000, and 25,000 to 300,000. Particularly preferred.

  The polyolefin resin film layer constituting the present invention preferably contains an antioxidant because fish eyes are reduced. The antioxidant preferably contained is not particularly limited, and examples thereof include phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, amine antioxidants, lactone antioxidants, and vitamin E. And system antioxidants.

  Among these antioxidants, 2,6-di-t-butyl-4-methylphenol and 2,6-di-t-butyl-4-ethylphenol have a great effect of suppressing the formation of crosslinked gel. Is preferred.

  The amount of the antioxidant in the polyolefin resin film layer constituting the present invention is preferably 0.1 to 100 ppm because the resulting adhesive polyolefin resin laminated film has few fish eyes and is excellent in stain resistance. 0.1 to 50 ppm is more preferable, and 0.1 to 10 ppm is particularly preferable.

  The polyolefin resin film layer constituting the present invention may contain various additives as long as the effects of the present invention are not impaired. Examples of additives include dyes, organic pigments, inorganic pigments, inorganic reinforcing agents, plasticizers, acrylic processing aids and other processing aids, ultraviolet absorbers, light stabilizers, foaming agents, lubricants, waxes, crystal nucleating agents. , Plasticizer, mold release agent, hydrolysis inhibitor, antiblocking agent, antistatic agent, antifogging agent, antifungal agent, rust inhibitor, ion trap agent, flame retardant, flame retardant auxiliary, inorganic filler, organic A filler etc. can be mentioned.

  The method for obtaining a polyolefin resin film used for the polyolefin resin film layer constituting the present invention is, for example, a method of forming a film after heating and melting the polyolefin resin, a method of forming a film after dissolving the polyolefin resin in a solvent, etc. Is mentioned.

  Examples of the method for forming a film after heating and melting the polyolefin resin include an inflation method (air cooling method, water cooling method), a T-die method, a calendar method, and the like.

  Examples of the method for forming a film after dissolving the polyolefin resin in the solvent include, for example, a step of preparing the polyolefin solution by dissolving the polyolefin resin in the solvent, and then continuously casting the polyolefin solution on the substrate. And a solution casting method comprising a step of evaporating the solvent by heating.

  Above all, the polyolefin resin film obtained has less fish eyes, the step of preparing a polyolefin solution by dissolving the polyolefin resin in a solvent, and then casting the polyolefin solution on the substrate, followed by heating to evaporate the solvent A solution casting method comprising steps is preferred.

  Each step of the solution casting method, which is a preferred production method, will be described below.

1) Step of preparing polyolefin solution The solvent used in the step of preparing polyolefin solution is not particularly limited as long as it is a solvent that dissolves polyolefin resin. For example, halogen solvent, boiling point is 70 to 140 ° C., solubility index is Examples thereof include at least one non-halogen solvent selected from an aliphatic hydrocarbon compound, an aromatic hydrocarbon compound, an ether compound, and an acetal compound that are 13 to 20 MPa ^1/2 . These solvents can be used in combination of two or more, and the ratio is not particularly limited.

  Examples of the halogen-based solvent include 1,1-dichloroethane, 1,2-dichloroethane, methylene chloride, chloroform, 1,1,1-trichloroethane, 1,1,2-trichloroethane, carbon tetrachloride, trichloroethylene, and perchloroethylene. Brominated solvents such as ethane bromide; Fluorinated solvents such as monofluorobenzene, 1,4-difluorobenzene, perfluoroheptane, perfluorooctane, dichloropentafluoropropane; bromochloromethane, 1, Examples include a solvent containing bromine and fluorine such as 2-dibromo-1,1-difluoroethane.

Examples of non-halogen solvents for aliphatic hydrocarbon compounds, aromatic hydrocarbon compounds, ether compounds, and acetal compounds having a boiling point of 70 to 140 ° C. and a solubility index of 13 to 20 MPa ^1/2 include, for example, n -Heptane, 2-methylhexane, 3-methylhexane, 2,3-dimethylpentane, 2,4-dimethylpentane, n-octane, 2,2,3-trimethylpentane, isooctane, 2,2,5-trimethylhexane Aliphatic hydrocarbon compounds such as 1-heptene, 1-octene, methylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane and cyclohexene; aromatic hydrocarbons such as benzene, toluene, m-xylene, p-xylene and ethylbenzene Compounds; cyclopentyl methyl ether, ethyl amino Examples include ether compounds such as no ether, dioxane and dipropyl ether; and acetal compounds such as diethyl acetal.

  Among these solvents, a solvent capable of dissolving the polyolefin resin at, for example, 80 to 120 ° C. is preferable from the viewpoint of solubility of the polyolefin resin, and a solvent having a low boiling point is preferable from the viewpoint of evaporation of the solvent. From these viewpoints, 1,1,2-trichloroethane, n-heptane, methylcyclohexane, toluene and cyclopentylmethyl ether are preferable, and 1,1,2-trichloroethane and methylcyclohexane are more preferable.

  The melting temperature of the polyolefin resin is appropriately determined depending on the solvent and polyolefin to be used. If the polyolefin resin does not dissolve below the boiling point of the solvent used, it can be dissolved at a temperature above the boiling point of the solvent using a pressure vessel if necessary, but the boiling point at normal pressure of the solvent used. It is preferable from the economical aspect to dissolve in the following. Although there is no restriction | limiting in particular in dissolution temperature, 60-200 degreeC is preferable and 70-150 degreeC is further more preferable.

  The dissolution time depends on the shape of the polyolefin resin used and the dissolution temperature, and is preferably 20 minutes to 8 hours, for example, and more preferably 30 minutes to 2 hours. Moreover, it is necessary to completely dissolve the polyolefin resin, and it is preferable to dissolve the polyolefin resin until a certain solution viscosity is reached.

  Moreover, there is no restriction | limiting in particular in the apparatus to melt | dissolve, For example, a vessel, a tube, a horizontal reactor, an extruder etc. can be used. The dissolution is preferably carried out with stirring.

  The polyolefin solution obtained by dissolving the polyolefin resin in a solvent is preferably filtered to remove foreign substances, and the filtration is preferably performed in a state where the polyolefin resin is dissolved. There is no restriction | limiting in particular in the filtration method, A well-known method can be used, For example, natural filtration, centrifugal filtration, pressure filtration, reduced pressure filtration, decantation etc. are mentioned. Examples of the filter medium include metal mesh, laminated wire mesh sintered body, metal nonwoven fabric sintered body, resin woven fabric, resin nonwoven fabric, resin membrane, filter fabric, paper, and the like. These filter media can be used singly or in combination, and filtration can be performed in multiple stages in order to increase filtration accuracy. The opening of the filter medium is preferably 100 μm or less, more preferably 50 μm or less, and particularly preferably 30 μm or less.

  There is no restriction | limiting in particular in the temperature at the time of filtering a polyolefin solution, For example, it can carry out in the state etc. in which the polyolefin resin melt | dissolved below the boiling point of the solvent to be used.

  There is no restriction | limiting in particular in the density | concentration of polyolefin solution, It can set suitably with the selected solvent, 0.1 to 50 weight% is preferable, 1 to 30 weight% is further more preferable, and 5 to 25 weight% is especially. preferable.

2) Process of evaporating solvent As a method of evaporating the solvent, for example, a method in which a polyolefin solution is cast on a base material to form a thin film and then heated is exemplified.

  As the base material, various resin films represented by polyester films such as polyethylene terephthalate (PET) and polyethylene naphthalate, and various resins whose surfaces are subjected to surface treatment by hard coating such as silicon treatment and acrylic resin. Examples thereof include various resin films obtained by subjecting these resin films to metal vapor deposition. Furthermore, examples include metal foils such as aluminum, copper, and stainless steel, various films such as metal films and metal sheets, polymer coatings on these metal materials as necessary, and inorganic coatings. it can. Further, it can be cast on a heated rotating metal drum as necessary, and can be cast on an endless polymer belt or metal belt.

  There is no restriction | limiting in particular in the method of casting a polyolefin solution on a base material, For example, a gravure coater method, a comma coater method, a die coater method, a double Mayer bar coater method, a doctor blade method etc. are illustrated. When heating is required to dissolve the polyolefin resin and the boiling point of the solvent is low, a die coater is used to suppress the increase in viscosity of the polyolefin solution due to rapid volatilization of the solvent during the casting process. Is preferred. The thickness of the polyolefin solution on the substrate immediately after being formed by casting is preferably 3 to 500 μm, and the casting speed is 0.5 to 50 m independent of the thickness of the polyolefin resin layer immediately after being formed on the substrate. / Min is preferred.

  Drying of the polyolefin solution layer formed on the substrate can be carried out in one step to multiple steps, and the temperature range is preferably 50 to 200 ° C. When drying in multiple steps, the temperature is 50 to 100 ° C. It is preferable to take a method such as primary drying and secondary drying in the range of 100 to 200 ° C. Moreover, it is also possible to perform drying in 3 steps or more as required. This drying can be carried out efficiently industrially using a drying furnace adjacent to the die coater. The polyolefin resin layer is peeled off from the substrate after sufficient drying and wound up, or peeled off from the substrate in the course of drying, and only the polyolefin resin layer is dried and wound into a film, and the polyolefin resin A film can be obtained.

  The adhesive polyolefin resin laminated film of this invention has the said polyolefin resin film layer and an adhesive layer.

  The pressure-sensitive adhesive used for the pressure-sensitive adhesive layer of the pressure-sensitive adhesive polyolefin resin laminated film of the present invention is not particularly limited. For example, a rubber-based pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, an ethylene-vinyl acetate pressure-sensitive adhesive, Examples thereof include a polyvinyl ether adhesive, a silicone adhesive, and the like, and a rubber adhesive and an acrylic adhesive are preferable because they have appropriate adhesiveness and peelability. These adhesives may be used independently and 2 or more types may be used together.

  There is no restriction | limiting in particular as a rubber-type adhesive, For example, the adhesive etc. which consist of an elastomer which shows rubber-like elasticity at room temperature, and a tackifier are mentioned.

  Examples of elastomers that exhibit rubber-like elasticity at room temperature include natural rubber; synthetic rubbers such as styrene-butadiene copolymer rubber, polyisoprene rubber, butyl rubber, polyisobutylene, and polybutene; styrene-butadiene block copolymer (SB), styrene. -Isoprene block copolymer (SI), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene obtained by hydrogenating these conjugated diene moieties- Ethylene-butylene block copolymer (SEB), styrene-ethylene-propylene block copolymer (SEP), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SE Include S) block copolymers such as etc., These may be used singly or in combination of two or more.

  Examples of tackifiers include aliphatic petroleum resins, alicyclic petroleum resins, aromatic petroleum resins, rosin resins, terpene resins, coumarone indene resins, and hydrogenated products thereof. It is done. These tackifiers may be used alone or in combination of two or more.

  The composition of an elastomer that exhibits rubber-like elasticity at room temperature and the tackifier is superior in heat resistance and tackiness of the rubber-based adhesive, so that the tackifier is used for 100 parts by weight of the elastomer that exhibits rubber-like elasticity at room temperature. The amount is preferably 10 to 200 parts by weight, more preferably 20 to 150 parts by weight, and particularly preferably 20 to 100 parts by weight.

  There is no restriction | limiting in particular as an acrylic adhesive, For example, 1 type (s) or 2 or more types of monomers, such as (meth) acrylic acid ester which has a C1-C18 alkyl group, and a copolymerization modification monomer Examples thereof include acrylic polymers homopolymerized or copolymerized by solution polymerization, emulsion polymerization, and the like.

  Specific examples of the monomer such as (meth) acrylic acid ester include (meth) acrylic acid ester having an alkyl group such as butyl group, 2-ethylhexyl group, isooctyl group and isononyl group. Specific examples of the copolymerizable modifying monomer include, for example, an ester of (meth) acrylic acid having an alkyl group such as an ethyl group or a methyl group, (meth) acrylonitrile, vinyl acetate, styrene, (meth) acrylic acid , Maleic anhydride, vinyl pyrrolidone, (meth) acrylic acid ester having glycidyl group, dimethylaminoethyl group or hydroxyl group, (meth) acrylamide, vinylamine, allylamine, polyfunctional (meth) acrylate and the like.

  The acrylic polymer can be used as the base polymer of the pressure sensitive adhesive as it is, but it is preferable to add a crosslinking agent for the purpose of improving the cohesive strength of the pressure sensitive adhesive. Examples of the crosslinking agent include polyfunctional epoxy compounds and polyfunctional isocyanate compounds. In addition, you may give the crosslinking process by radiation irradiation.

  The polyfunctional epoxy compound is not particularly limited as long as it has two or more epoxy groups in the molecule. For example, sorbitol tetraglycidyl ether, trimethylolpropane glycidyl ether, tetraglycidyl-1,3-bisaminomethyl Examples include cyclohexane, tetraglycidyl-m-xylenediamine, and triglycidyl-p-aminophenol. The polyfunctional isocyanate compound is not particularly limited as long as it has two or more isocyanate groups in the molecule, and examples thereof include diphenylmethane diisocyanate, tolylene diisocyanate, and hexamethylene diisocyanate.

  These crosslinking agents can be used singly or in combination of two or more, and the amount used can be appropriately selected according to the composition and molecular weight of the acrylic polymer. At that time, a crosslinking catalyst such as dibutyltin dilaurate may be added to promote the reaction.

  Commercially available products of acrylic adhesives include, for example, Nippon Synthetic Chemical Industry Co., Ltd. trade names: Coponil NS-001, NS-002, NS-004, Toagosei Co., Ltd. trade names: Aron Tuck HV-C9500, HV -C7560 etc. are mentioned.

  Examples of the urethane pressure-sensitive adhesive include a composition in which the tackifier is added to a reaction product of a polyol and the polyfunctional isocyanate compound, and an oligomer having a urethane bond and having a (meth) acryloyl group at the terminal.

  The polyol is not particularly limited as long as it has two or more hydroxyl groups in the molecule, and examples thereof include polyether polyols and polyester polyols.

  Also, an oligomer having a urethane bond and having a (meth) acryloyl group at the end generates a urethane oligomer by reaction of a diol molecule having a hydroxyl group at the end with a diisocyanate molecule, such as an alkylene diol or a polyether compound. , Reacting a compound having a (meth) acryloyl group at the terminal functional group, or reacting a polyether compound or polyester compound having a hydroxyl group at the terminal with a compound having a (meth) acryloyl group and an isocyanate group. Obtained.

  Examples of the ethylene-vinyl acetate pressure-sensitive adhesive include ethylene-vinyl acetate copolymers having a vinyl acetate content of 40 to 90%. Examples of commercially available products include Levermelt manufactured by LANXESS.

  Examples of the polyvinyl ether pressure-sensitive adhesive include homopolymers such as vinyl ethyl ether, vinyl butyl ether, vinyl isobutyl ether, and copolymers.

  Examples of the silicone-based pressure-sensitive adhesive include silicone raw rubber such as polydimethylsiloxane and polydimethyldiphenylsiloxane, and trimethylsilane which is made of a three-dimensional silicate having a silanol group terminal. As a commercial item, Shin-Etsu Chemical Co., Ltd. make, brand name: Shin-Etsu silicone KR-100, KR-101-10, KR-130, X-40-3102, X-40-3229 etc. are mentioned, for example.

  The pressure-sensitive adhesive used for the pressure-sensitive adhesive layer of the pressure-sensitive adhesive polyolefin resin laminated film of the present invention may contain various additives as long as the effects of the present invention are not impaired. Additives include, for example, tackifiers, release modifiers, crosslinkers, fillers, extenders, softeners, plasticizers, surfactants, coupling agents, antioxidants, anti-aging agents, thermal stability Agents, light stabilizers, ultraviolet absorbers, colorants, lubricants, antistatic agents, flame retardants, solvents, and the like, and one or more of these may be added.

  The form of the pressure-sensitive adhesive used for the pressure-sensitive adhesive layer of the pressure-sensitive adhesive polyolefin resin laminated film of the present invention is not particularly limited. For example, a solvent-type pressure-sensitive adhesive, an emulsion-type pressure-sensitive adhesive, a hot-melt-type pressure-sensitive adhesive, and a photopolymerization-type pressure-sensitive adhesive Or any other form. Further, the pressure-sensitive adhesive used in the pressure-sensitive adhesive layer of the pressure-sensitive polyolefin resin laminated film of the present invention may be a non-crosslinked pressure-sensitive adhesive, a cross-linked pressure-sensitive adhesive, or a one-component pressure-sensitive adhesive. It may be a multi-component type adhesive having two or more liquids.

  The method for preparing the pressure-sensitive adhesive used in the adhesive layer constituting the present invention is not particularly limited, and for example, a pressure-sensitive adhesive component using a normal stirring kneader such as a mixer, kneader, roll, or extruder. A method of uniformly stirring and kneading each predetermined amount and each predetermined amount of various additives added as necessary at room temperature or under heating.

The pressure-sensitive adhesive polyolefin resin laminate film of the present invention is produced by applying the above pressure-sensitive adhesive to a polyolefin resin film layer having a fish eye of 50 μm or more and 10 pieces / m ² or less.

  As a method for producing the pressure-sensitive adhesive polyolefin resin laminated film of the present invention, for example, using a normal coating machine such as a roll coater, a pressure-sensitive adhesive is directly applied to a predetermined surface of the polyolefin resin film layer. After the steps of drying, cooling, light irradiation, etc., the pressure-sensitive adhesive layer is formed by the direct coating method for laminating the pressure-sensitive adhesive layer, the same method as described above on the release treatment surface of the release layer. Is laminated on a predetermined surface of the polyolefin resin film layer, and a transfer method in which the pressure-sensitive adhesive layer is transferred to a predetermined surface of the polyolefin resin film layer, a polyolefin resin for the polyolefin resin film layer and a pressure-sensitive adhesive for the pressure-sensitive adhesive layer. Examples thereof include a co-extrusion method. Of these, the direct application method is preferred because the resulting adhesive layer has few fish eyes.

  In order to further enhance the adhesiveness of the pressure-sensitive adhesive layer, it is preferable to subject the predetermined surface of the polyolefin resin film layer to surface treatment such as corona discharge treatment, plasma discharge treatment, and primer coating in advance.

  There is no restriction | limiting in particular in the thickness of an adhesive layer, It is preferable that it is 3-50 micrometers from a sticky and peelable viewpoint, More preferably, it is 5-30 micrometers.

  Moreover, since the obtained adhesive polyolefin resin laminated | multilayer film can be preserve | saved in the state wound by the roll, it is preferable that it is what has a release layer on at least one outermost surface layer, and also is adhesive. It is preferably an adhesive polyolefin resin laminated film having a structure of adhesive layer / polyolefin resin film layer / release layer or release layer / adhesive layer / polyolefin resin film layer, and in particular, adhesive layer / polyolefin resin. A pressure-sensitive polyolefin resin laminated film having a configuration of film layer / release layer with the release-treated surface outside or release layer / adhesive layer / polyolefin resin film layer with the release-treated surface inside is preferable.

  There is no restriction | limiting in particular as a mold release layer, For example, the resin film, paper, etc. which carried out the peeling process can be mentioned. Examples of the resin film include polytetrafluoroethylene, 4-fluoroethylene-perchloroalkoxy copolymer, 4-fluoroethylene-6-fluoropropylene copolymer, 2-ethylene-4-fluoroethylene copolymer. Polymers, fluororesin films such as polyvinylidene fluoride and polyvinyl fluoride; polyester films such as polyethylene terephthalate and polyethylene naphthalate; polycarbonate films, polyamide films, polymethyl methacrylate films, polyvinyl alcohol films, polyethylene films, and ethylene-vinyl acetate Examples thereof include a resin film such as a polymer saponified film.

  There is no particular limitation on the release treatment, and for example, a silicone release treatment, a fluorine release treatment, a (meth) acrylic release treatment having a long chain alkyl group, or a vinyl ether release treatment having a long chain alkyl group can be used. A silicone-based release treatment having excellent peelability is preferable.

  The adhesive polyolefin resin laminated film of the present invention can be used as a protective film, and there are no particular restrictions on the object to be protected. Examples of the object to be protected include metals such as painted steel plates, aluminum plates, stainless steel plates; polycarbonate plates, acrylics Examples thereof include resin plates such as plates and styrene plates; optical members such as polarizing plates, optical films, prism sheets, light guide plates, retardation films, and diffusion plates; automobile parts, semiconductor members, and nameplates.

  INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an adhesive polyolefin resin laminated film having an extremely wide industrial application range, having a small fish eye and excellent appearance, and a protective film using the same. The adhesive polyolefin resin laminated film of the present invention is useful as, for example, a protective film that requires high quality.

  The present invention will be described in more detail with reference to the following examples. However, these are examples for helping understanding of the present invention, and the present invention is not limited to these examples.

<Polyolefin resin>
(1) Polyethylene LDPE: Low density polyethylene, Petrocene (registered trademark) 175K (MFR = 0.6 g / 10 min, density = 922 kg / m ³ ), manufactured by Tosoh Corporation (2) Ethylene-vinyl acetate copolymer EVA: Ethylene-vinyl acetate copolymer, Ultracene (registered trademark) 520F (vinyl acetate content 8 wt%, MFR = 2.0 g / 10 min, density = 928 kg / m ³ ), manufactured by Tosoh Corporation (3) ethylene- Saponified vinyl acetate copolymer EVA-OH: Saponified ethylene-vinyl acetate copolymer, Mersen H (registered trademark) H-6410M (MFR = 19 g / 10 min, density = 950 kg / m ³ ), manufactured by Tosoh Corporation <Base material>
(1) PET film PET-1; Purex (registered trademark) A31, single-sided silicone-based release treatment, thickness: 75 μm, Teijin DuPont Films Co., Ltd. PET-2; Melinex (registered trademark) type S (thickness: 100 μm), Teijin DuPont Films Co., Ltd. <Casting>
The coating was performed using a coating machine provided with a die having a width of 300 mm that can be heated. The polymer solution dissolved in the autoclave was transferred to a 5 L scale pressurizable tank equipped with a heating jacket and a nitrogen introduction valve manufactured by Unicontrols. The polymer solution in the tank was transferred to the die by pressurizing the tank. The tank and the die were connected to the extraction valve at the bottom of the tank with a Teflon (registered trademark) tube in which a hose heater manufactured by Mysec Co., Ltd. was applied, and kept at a constant temperature.

  The temperature of the die is controlled using a mold temperature controller TSW-75S manufactured by Nippon Mold Industry Co., Ltd., and the temperature of the hose heater and the heating tank is adjusted using HST-120CT manufactured by Mysec Co., Ltd. .

<Fisheye measurement>
A fluorescent lamp was irradiated from under the obtained film, and the number and size of fish eyes in the film were measured visually or using a magnifying glass, and the number was calculated as the number per 1 m ² .

<Measurement of density>
The density of the polyolefin resin film was measured by a density-squeeze tube method in accordance with JIS K7112 (1999).

Example 1
3.6 kg of LDPE pellets and 28.8 kg of 1,1,2-trichloroethane were charged into a 30 L autoclave and stirred at 110 ° C. for 2 hours under heating to dissolve LDPE to obtain a polyolefin solution. While filtering this solution through a 500 mesh metal net, 3 L of the solution was transferred to a 5 L tank heated to 105 ° C. The tank is pressurized with nitrogen and fed to a 300 mm wide coating die heated to 105 ° C. through a Teflon (registered trademark) tube with a heating jacket kept at 105 ° C., and the polyolefin solution is the base material from the die. It was cast on a surface of PET-1 that had not been subjected to the silicone-based release treatment and dried at 150 ° C. The speed of PET-1 was set at 2 m / min. The LDPE film was peeled from the obtained PET-1 and LDPE film laminate to obtain a polyolefin resin film. The thickness, fish eye, and density of the obtained polyolefin resin film were measured. The results are shown in Table 1.

得られたポリオレフィン樹脂フィルムの５０μｍ以上のフィッシュアイは０．８個／ｍ^２で外観の優れた品質のフィルムであった。

The obtained polyolefin resin film had a fish eye of 50 μm or more and a quality of excellent appearance with 0.8 pieces / m ² .

  On the other hand, 100 parts by weight of styrene-isoprene-styrene block copolymer (Kraton Co., Ltd., Kraton D-1107), hydrogenated petroleum resin (hydrogenated aromatic petroleum resin) Alcon P-90 (tackifier) A rubber-based adhesive was prepared in advance by mixing 100 parts by weight of Arakawa Kogyo Co., Ltd.) at 180 ° C.

  Next, a rubber-based adhesive is applied on the LDPE film of the laminate of PET-1 and LDPE film obtained above using a pilot coater (manufactured by Inoue Metal Industry Co., Ltd.) to a thickness of 10 μm and wound. An adhesive polyolefin resin laminated film was obtained.

  The obtained adhesive polyolefin resin laminated film was excellent in appearance.

  Furthermore, when the obtained adhesive polyolefin resin laminated film was affixed as a protective film for a polycarbonate plate, it was a high-quality protective film that had no defects such as fish eyes and no film lift.

Example 2
2.5 kg of EVA pellets and 15.4 kg of methylcyclohexane were charged into a 30 L autoclave and stirred at 110 ° C. for 2 hours under heating to dissolve EVA and obtain a polyolefin solution. While filtering this solution through a 500 mesh metal net, 3 L of the solution was transferred to a 5 L tank heated to 105 ° C. The tank is pressurized with nitrogen and fed to a 300 mm wide coating die heated to 105 ° C. through a Teflon (registered trademark) tube with a heating jacket kept at 105 ° C., and the polyolefin solution is the base material from the die. It was cast on PET-2 and dried at 150 ° C. The speed of the PET film was set at 2 m / min. EVA-2 was peeled from the obtained PET-2 and EVA film laminate to obtain a polyolefin resin film. The thickness, fish eye, and density of the obtained polyolefin resin film were measured. The results are shown in Table 1.

The obtained polyolefin resin film had a fish eye of 50 μm or more and a quality of excellent appearance with 0.9 pieces / m ² .

  Next, an acrylic pressure-sensitive adhesive ARONTAC HV-C9500 (manufactured by Toagosei Co., Ltd.) is used as a pilot coater (manufactured by Inoue Metal Industry Co., Ltd.) on the EVA film of the laminate of PET-2 and EVA film obtained above. After coating and drying to a thickness of 10 μm, the PET-1 silicone release treatment surface is laminated on the acrylic adhesive, and the PET-2 is taken up and peeled off, and the adhesive polyolefin resin is laminated. A film was obtained.

  The obtained adhesive polyolefin resin laminated film was excellent in appearance.

  Furthermore, when the obtained adhesive polyolefin resin laminated film was affixed as a protective film for a SUS314 plate, it was a high-quality protective film that had no defects such as fish eyes and no film lift.

Example 3
3.6 kg of EVA-OH pellets and 28.8 kg of 1,1,2-trichloroethane were charged into a 30 L autoclave and stirred for 2 hours at 110 ° C. with heating to dissolve the EVA-OH to obtain a polyolefin solution. While filtering this solution through a 500 mesh metal net, 3 L of the solution was transferred to a 5 L tank heated to 105 ° C. The tank is pressurized with nitrogen and fed to a 300 mm wide coating die heated to 105 ° C. through a Teflon (registered trademark) tube with a heating jacket kept at 105 ° C., and the polyolefin solution is the base material from the die. It was cast on a surface of PET-1 that had not been subjected to the silicone-based release treatment and dried at 150 ° C. The speed of PET-1 was set at 2 m / min. The EVA-OH film was peeled from the resulting laminate of PET-1 and EVA-OH film to obtain a polyolefin resin film. The thickness, fish eye, and density of the obtained polyolefin resin film were measured. The results are shown in Table 1.

The obtained polyolefin resin film had a fish eye of 50 μm or more and a quality of excellent appearance with 1.0 pieces / m ² .

  Next, an acrylic pressure-sensitive adhesive HV-C9500 (manufactured by Toagosei Co., Ltd.) was placed on the EVA-OH film of the laminate of PET-1 and EVA-OH film obtained above as a pilot coater (Inoue Metal Industry Co., Ltd.). Used), and coated to dryness and wound up to obtain an adhesive polyolefin resin laminated film.

  The obtained adhesive polyolefin resin laminated film was excellent in appearance.

  Furthermore, when the obtained adhesive polyolefin resin laminated film was affixed as a protective film for a SUS314 plate, it was a high-quality protective film that had no defects such as fish eyes and no film lift.

Example 4
Acrylic adhesive ARONTAC HV-C9500 (manufactured by Toagosei Co., Ltd.) was used on the EVA film of the laminate of PET-2 and EVA film obtained in Example 2 using a pilot coater (manufactured by Inoue Metal Industry Co., Ltd.) After coating and drying to a thickness of 10 μm, PET-2 was peeled off to obtain an adhesive polyolefin resin laminated film.

  The obtained adhesive polyolefin resin laminated film was excellent in appearance.

  Furthermore, when the obtained adhesive polyolefin resin laminated film was affixed as a protective film for a SUS314 plate, it was a high-quality protective film that had no defects such as fish eyes and no film lift.

Comparative Example 1
The pellets of LDPE were supplied to an extruder of an extrusion laminator having a screw of 25 mmφ and extruded from a T-die at a temperature of 250 ° C. on the surface of the base material PET-1 which was not subjected to the silicone-based release treatment, and the LDPE was laminated. . The LDPE film was peeled off from the laminate of the obtained PET film and LDPE film to obtain a polyolefin resin film. The thickness of the obtained polyolefin resin film was measured fisheyes, and a density, thickness 30 [mu] m, 50 [mu] m or more fish eyes 20 / ^{m 2,} a density of 922 kg / ^{m 3.}

  The obtained polyolefin resin film had many fish eyes and was inferior in appearance.

  Next, in the same manner as in Example 1, a rubber adhesive is used on the LDPE film of the obtained PET-1 and LDPE film laminate so that the thickness becomes 10 μm using a pilot coater (manufactured by Inoue Metal Industry Co., Ltd.). It was applied and wound up to obtain an adhesive polyolefin resin laminated film.

  The obtained adhesive polyolefin resin laminated film was inferior in appearance.

  Furthermore, when the obtained adhesive polyolefin resin laminated film was affixed as a protective film for a polycarbonate plate, it was a protective film with many defects such as fish eyes and poor film quality.

Comparative Example 2
EVA pellets were supplied to an extruder of an extrusion laminator having a 25 mmφ screw, and extruded from a T-die at a temperature of 190 ° C. on the surface of the PET-1 substrate, which was not subjected to silicone-based release treatment, to laminate EVA. . The EVA film was peeled off from the obtained PET film and EVA film laminate to obtain a polyolefin resin film. The thickness of the obtained polyolefin resin film was measured fisheyes, and a density, thickness 40 [mu] m, 50 [mu] m or more fish eyes 30 / ^{m 2,} a density of 928 kg / ^{m 3.}

  The obtained polyolefin resin film had many fish eyes and was inferior in appearance.

  Next, in the same manner as in Example 1, a rubber adhesive is used on the EVA film of the obtained PET-1 and EVA film laminate so that the thickness becomes 10 μm using a pilot coater (manufactured by Inoue Metal Industry Co., Ltd.). It was applied and wound up to obtain an adhesive polyolefin resin laminated film.

  The obtained adhesive polyolefin resin laminated film was inferior in appearance.

  Furthermore, when the obtained adhesive polyolefin resin laminated | multilayer film was stuck as a protective film of a SUS314 board, there were many defects, such as a fish eye, and it was a protective film with inferior quality in which the float of the film was seen.

Comparative Example 3
EVA-OH pellets were supplied to an extruder of an extrusion laminator having a screw of 25 mmφ, and extruded from a T-die at a temperature of 210 ° C. on the surface of the PET-1 substrate, which was not subjected to the silicone-based release treatment. OH was laminated. The EVA-OH film was peeled from the laminate of the obtained PET film and EVA-OH film to obtain a polyolefin resin film. The thickness of the obtained polyolefin resin film was measured fisheyes, and a density, thickness 40 [mu] m, 50 [mu] m or more fish eyes 25 / ^{m 2,} a density of 950 kg / ^{m 3.}

  The obtained polyolefin resin film had many fish eyes and was inferior in appearance.

  Next, in the same manner as in Example 3, an acrylic pressure-sensitive adhesive was used on the EVA-OH film of the laminate of the obtained PET-1 and EVA-OH film, using a pilot coater (manufactured by Inoue Metal Industry Co., Ltd.). It was applied to a thickness of 10 μm, dried and wound up to obtain an adhesive polyolefin resin laminated film.

  The obtained adhesive polyolefin resin laminated film was inferior in appearance.

  Furthermore, when the obtained adhesive polyolefin resin laminated | multilayer film was stuck as a protective film of a SUS314 board, there were many defects, such as a fish eye, and it was a protective film with inferior quality in which the float of the film was seen.

  The adhesive polyolefin resin laminated film of the present invention and a protective film using the same are useful as, for example, a protective film requiring high quality because it has less fish eyes and is excellent in appearance.

Claims (8)

A pressure-sensitive polyolefin resin laminated film comprising a polyolefin resin film layer having a fish eye of 50 μm or more and 10 pieces / m ² or less, and a pressure-sensitive adhesive layer. The polyolefin resin film layer is at least one polyolefin resin film layer selected from the group consisting of polyethylene, ethylene-vinyl acetate copolymer, and saponified ethylene-vinyl acetate copolymer. 2. The adhesive polyolefin resin laminated film according to 1. The polyolefin resin film layer is manufactured from a step of preparing a polyolefin solution by dissolving a polyolefin resin in a solvent, and subsequently a step of casting the polyolefin solution on a substrate and then evaporating the solvent by heating. The adhesive polyolefin resin laminated film according to claim 1 or 2, characterized in that The adhesive polyolefin resin laminated film according to claim 3, wherein the solvent is 1,1,2-trichloroethane and / or methylcyclohexane. The pressure-sensitive adhesive layer is at least one pressure-sensitive adhesive selected from the group consisting of a rubber-based pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, an ethylene-vinyl acetate pressure-sensitive adhesive, a polyvinyl ether-based pressure-sensitive adhesive, and a silicone-based pressure-sensitive adhesive. The adhesive polyolefin resin laminated film according to any one of claims 1 to 4, wherein the adhesive polyolefin resin laminated film is. The adhesive polyolefin resin laminated film according to any one of claims 1 to 5, further comprising a release layer on at least one outermost surface layer. The pressure-sensitive adhesive polyolefin resin laminated film according to claim 6, which is a pressure-sensitive adhesive layer / polyolefin resin film layer / release layer or a release layer / pressure-sensitive adhesive layer / polyolefin resin film layer. A protective film comprising the adhesive polyolefin resin laminated film according to any one of claims 1 to 7.