JP2784030B2 - Manufacturing method of laminated film - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a laminated film including a liquid crystal polymer layer suitable as a packaging film or the like using a co-extrusion molding machine.

[Problems to be Solved by Conventional Techniques and the Invention] In recent years, as the types of objects to be packaged have expanded, various types of packaging films according to applications have been developed. For example,
As packaging films, high-strength films, high-elastic films, flexible films, adhesive films, transparent films, conductive films, light-shielding films, gas barrier films, heat-resistant films, chemical-resistant films, etc. Composite films and the like are known. However, since these packaging films have significantly different properties of the constituent polymers, they are properly used depending on the application, and it is difficult for one film to simultaneously satisfy a plurality of properties.

On the other hand, liquid crystal polymers belonging to the area of engineering plastics are excellent in mechanical properties, dimensional stability, heat resistance, chemical stability, gas barrier properties, etc., and also have good electrical properties. It is attracting attention as a raw material polymer for a film satisfying the following.

However, liquid crystalline polymer films are split to obtain highly elastic split fibers.
As is clear from Japanese Patent Application Laid-Open No. 60-42287), the strength of the film in the width direction (hereinafter referred to as TD direction) is extremely weak.

In order to improve the strength of the liquid crystal polymer film in the TD direction, various methods have been studied. For example, a method of obtaining a biaxially oriented film by increasing the blow-up ratio by an inflation method (JP-A-56-46728, JP-A-61-102234), a method of rotating a ring die by an inflation method (particularly, JP-A-56-2127, JP-A-63-173620), a method of internally providing a plate-like porous body having a large number of heatable slits inside a T-die (Japanese Patent Laid-Open No. 58-59818) Gazette) Using a three-layer coextrusion die, the liquid crystal polymer layer is used as an intermediate layer, and both outer layers are formed of a liquid crystal polymer and a non-adhesive thermoplastic polymer such as polycarbonate and polyolefin. A method has been proposed in which, after extrusion, the outer layer is peeled off and the liquid crystal polymer film of the intermediate layer is taken out (JP-A-63-31729).

However, the liquid crystalline polymer film obtained as described above, even when formed into a film, for example, like polytetrafluoroethylene, does not have sufficient adhesiveness, and cannot secure heat sealability, hot melt adhesiveness, and the like. As such, its use is severely limited.

Accordingly, an object of the present invention is to produce a laminated film that can be economically and industrially produced into a film suitable as a packaging film and the like, while taking advantage of the excellent properties of a liquid crystalline polymer, having excellent strength and adhesiveness in the TD direction. It is to provide a method.

[Constitution of the Invention] As a result of intensive studies, the present inventors have found a thermoplastic polymer having excellent adhesion to a thermotropic liquid crystalline polymer film, and have completed the present invention. That is,
The present invention uses a co-extrusion molding machine, through a liquid crystal polymer layer, a thermoplastic polymer layer having adhesiveness to the liquid crystal polymer layer, and has no adhesiveness to the liquid crystal polymer layer. After extruding in the state of forming a thermoplastic polymer layer, a method of manufacturing a laminated film by peeling off the thermoplastic polymer layer having no adhesive, the carboxy group, as the thermoplastic polymer having the adhesive, A glycidyl group, and a modified polyolefin into which at least one functional group selected from an alkoxysilane group has been introduced,
Or polyvalent carboxylic acid component is 30-80 mol% terephthalic acid
The object is achieved by a method for producing a laminated film using a modified polyester composed of a modified polyester composed of adipic acid, sebacic acid and isophthalic acid, and 70 to 20 mol% of a polycarboxylic acid.

In the present specification, the liquid crystalline polymer means a thermotropic liquid crystal polymer and a composition thereof which are softened and flowable by heating, can be molded, and exhibit an anisotropic molten phase having birefringence when melted.

Also, a film is used to include all relatively thin, substantially flat structures that are sometimes referred to in the art as sheets or the like.

Examples of the above liquid crystalline polymer include polymers composed of the following components and the like.

(1) One or two or more aromatic dicarboxylic acids and alicyclic dicarboxylic acids (2) One or two or more aromatic diols, alicyclic diols, and aliphatic diols (3) One aromatic hydroxycarboxylic acid (4) One or two or more aromatic thiol carboxylic acids (5) One or two or more aromatic dithiols and aromatic thiol phenols (6) One or two aromatic hydroxyamines and aromatic diamines More than species.

Examples of the liquid crystalline polymer composed of the above components include: i) a polyester composed of the components (1) and (2); ii) a polyester composed of the component (3); iii) a polyester composed of the components (1) and (2). Iv) a polythiol ester consisting of component (4), v) a polythiol ester consisting of components (1) and (5), vi) a component (1), (4) and (4) Vii) a polyester amide comprising components (1), (3) and (5); viii) a polythiol ester comprising components (1), (2), (3) and (5) Is selected as a combination of the following polyesteramides.

Although not included in the category of the combination of the above components, such a liquid crystalline polymer includes an aromatic polyazomethine, and specific examples thereof include poly (nitrilo-2-methyl-1,4
Phenylene nitriloethylidine-1,4-phenyleneethylidine), poly (nitrilo-2-methyl-1,4-phenylene nitrilomethylidyne-1,4-phenylene methylidyne), and poly (nitrilo-2-chloro- 1,4-phenylene nitrilomethylidine-1,4-phenylene methylidyne) and the like.

Further, although not included in the category of the combination of the above components, such a liquid crystalline polymer includes polyester carbonate. This polymer essentially contains 4-oxybenzoyl, dioxyphenyl, dioxycarbonyl and terephthaloyl units.

As the aromatic dicarboxylic acid, terephthalic acid, 4,
4'-diphenyldicarboxylic acid, 4,4 "-triphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, diphenylether-4,4'-dicarboxylic acid, diphenoxyethane-4,4'-dicarboxylic acid, diphenoxybutane −4,4 ′
-Dicarboxylic acid, diphenylethane-4,4'-dicarboxylic acid, isophthalic acid, diphenylether-3,3'-dicarboxylic acid, diphenoxyethane-3,3'-dicarboxylic acid, diphenylethane-3,3'-dicarboxylic acid Aromatic dicarboxylic acids such as, naphthalene-1,6-dicarboxylic acid;
Alkyl, alkoxy or halogen-substituted aromatic dicarboxylic acids, such as chloroterephthalic acid, dichloroterephthalic acid, bromoterephthalic acid, methylterephthalic acid, dimethylterephthalic acid, ethylterephthalic acid, methoxyterephthalic acid, ethoxyterephthalic acid and the like. .

Examples of the alicyclic dicarboxylic acid include trans-1,4-cyclohexanedicarboxylic acid, cis-1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and other alicyclic dicarboxylic acids; alkyls of alicyclic dicarboxylic acids ,
Alkoxy or halogen substituents such as trans-
Examples thereof include 1,4- (1-methyl) cyclohexanedicarboxylic acid and trans-1,4- (1-chloro) cyclohexanedicarboxylic acid.

As aromatic diols, hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 4,4 "-dihydroxytriphenyl, 2,6-naphthalenediol, 4,4'-
Dihydroxydiphenyl ether, bis (4-hydroxyphenoxy) ethane, 3,3'-dihydroxyphenyl, 3,3'-dihydroxydiphenyl ether, 1,6-naphthalenediol, 2,2-bis (4-hydroxyphenyl) propane, 1-bis (4-hydroxyphenyl)
Aromatic diols such as methane; alkyl-, alkoxy- or halogen-substituted aromatic diols, for example, chlorohydroquinone, methylhydroquinone, 1-butylhydroquinone, phenylhydroquinone, methoxyhydroquinone, phenoxyhydroquinone, 4-chlororesorcin, 4-methylresorcinol And the like.

As the alicyclic diol, trans-1,4-cyclohexanediol, cis-1,4-cyclohexanediol, trans-1,4-cyclohexanedimethanol, trans-1,3-cyclohexanediol, cis-1,2- Alicyclic diols such as cyclohexanediol and trans-1,3-cyclohexanedimethanol; alkyl, alkoxy or halogen-substituted alicyclic diols such as trans-1,4- (1-methyl) cyclohexanediol, trans- 1,4- (1-chloro) cyclohexanediol and the like can be mentioned.

As the aliphatic diol, ethylene glycol, 1,3
-Linear or branched aliphatic diols such as propanediol, 1,4-butanediol and neopentyl glycol.

Examples of the aromatic hydroxycarboxylic acid include aromatic hydroxycarboxylic acids such as 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, and 6-hydroxy-1-naphthoic acid; aromatic hydroxycarboxylic acids Alkyl, alkoxy or halogen substituents of
For example, 3-methyl-4-hydroxybenzoic acid, 3,5-
Dimethyl-4-hydroxybenzoic acid, 2,6-dimethyl-
4-hydroxybenzoic acid, 3-methoxy-4-hydroxybenzoic acid, 3,5-dimethoxy-4-hydroxybenzoic acid, 6-hydroxy-5-methyl-2-naphthoic acid, 6
-Hydroxy-5-methoxy-2-naphthoic acid, 3-chloro-4-hydroxybenzoic acid, 2,3-dichloro-4-
Hydroxybenzoic acid, 3,5-dichloro-4-hydroxybenzoic acid, 2,5-dichloro-4-hydroxybenzoic acid,
3-bromo-4-hydroxybenzoic acid, 6-hydroxy-5-chloro-2-naphthoic acid, 6-hydroxy-7-
Chloro-2-naphthoic acid, 6-hydroxy-5,7-dichloro-2-naphthoic acid and the like can be mentioned.

Examples of the aromatic mercaptocarboxylic acid include 4-mercaptobenzoic acid, 3-mercaptobenzoic acid, 6-mercapto-2-naphthoic acid, and 7-mercapto-2-naphthoic acid.

As aromatic dithiols, benzene-1,4-dithiol, benzene-1,3-dithiol, naphthalene-2,6-
Dithiol, naphthalene-2,7-dithiol and the like.

Examples of the aromatic mercaptophenol include 4-mercaptophenol, 3-mercaptophenol, and 2-mercaptophenol.

As aromatic hydroxyamine and aromatic diamine,
2-aminophenol, N-methyl-4-aminophenol, 1,4-phenylenediamine, N-methyl-1,4-phenylenediamine, N, N'-dimethyl-1,4-phenylenediamine, 3-aminophenol 3-methyl-4-aminophenol, 2-chloro-4-aminophenol,
4-amino-1-naphthol, 4-amino-4'-hydroxydiphenyl, 4-amino-4'-hydroxydiphenyl ether, 4-amino-4'-hydroxydiphenylmethane, 4-amino-4'-hydroxydiphenyl sulfide, 4 4,4'-diaminophenyl sulfide (thiodianiline), 4,4'-diaminodiphenyl sulfone, 2,5-diaminotoluene, 4,4'-ethylenedianiline, 4,4'-diaminodiphenoxyethane, 4,4 ' -Diaminodiphenylmethane (methylenedianiline), 4,4 '
-Diaminodiphenyl ether (oxydianiline) and the like.

The polymers i) to vii comprising the above components
i) is a polymer having no birefringence at the time of melting depending on the constituent components, the composition ratio in the polymer, and the sequence distribution, but the polymer used in the present invention is one of the above polymers having birefringence at the time of melting. Limited.

The liquid crystalline polymer used in the present invention can be produced by a conventionally known method.

The wholly aromatic polymers preferably used in the present invention tend to be substantially insoluble in common solvents and are therefore unsuitable for solution processing. However, these polymers can be easily processed by conventional melt processing methods. It should be noted that particularly preferred fully aromatic polymers are somewhat soluble in pentafluorophenol.

The liquid crystalline polymer used in the present invention may have an appropriate molecular weight as long as film formability and the like are not impaired. For example, suitable fully aromatic polyesters usually have a weight average molecular weight of about 2,000 to 200,000, preferably about 10,000 to 50,000.
0, particularly preferably about 20,000 to 25,000. Suitable wholly aromatic polyesteramides typically have a molecular weight of about
5,000 to 50,000, preferably about 10,000 to 30,000, for example, 15,000 to 17,000. The determination of molecular weight can be carried out by gel permeation chromatography as well as other standard methods without melt formation of the polymer, for example by quantifying end groups by infrared spectroscopy on compression molded films. The molecular weight can also be measured using a pentafluorophenol solution and using a light scattering method.

The wholly aromatic polyester amide described above, when dissolved in pentafluorophenol at a temperature of 60 ° C. at a concentration of 0.1% by weight, has at least about 2.0 dl / g, for example, about 2.0 to 10.0 dl / g.
Logarithmic viscosity (IV) is generally indicated.

Particularly preferred polyesters forming an anisotropic molten phase include naphthalene partial units such as 6-hydroxy-2-naphthoyl, 2,6-dihydroxynaphthalene and 2,6-dicarboxynaphthalene in an amount of about 10 mol% or more. I do.
Preferred polyesteramides are those containing repeating units of the naphthalene moiety and a moiety consisting of 4-aminophenol or 1,4-phenylenediamine. Specifically, it is as follows.

(A) a polyester consisting essentially of the following repeating units I and II: The polyester contains about 10-90 mol% of unit I and about 10-90 mol% of unit II. In one embodiment the unit I
Is present in an amount of about 65-85 mol% (e.g., about 75 mol%). In other embodiments, Unit II is present in a low amount of about 15-35 mol%, preferably about 20-30 mol%. At least a part of the hydrogen atoms bonded to the ring is substituted with a substituent selected from the group consisting of an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a phenyl group, a substituted phenyl group, and a combination thereof. You may.

(B) a polyester consisting essentially of the following repeating units II, III and IV: This polyester contains about 30-70 mol% of unit II. The polyester preferably has units II of about 40 to
60 mol%, unit III is about 20-30 mol%, and unit IV is about 20
-30% by mole. At least a part of the hydrogen atoms bonded to the ring is substituted by a substituent selected from the group consisting of an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a phenyl group, a substituted phenyl group, and a combination thereof. You may.

(C) a polyester consisting essentially of the following repeating units II, IV, V and VI: Wherein R represents a methyl group, chloro, bromo or a combination thereof, and is a substituent for a hydrogen atom on an aromatic ring.
IV is about 5 to 35 mol%, unit V is about 5 to 18 mol% and unit
Contains about 20-40 mol% VI. The polyester preferably has a unit II of about 35-45 mol% and a unit IV of about 15-25
Mol%, unit V is about 10-15 mol%, and unit VI is about 25-35.
Mol%. However, the total molarity of the units IV and V is substantially equal to the molarity of the unit VI. Further, at least a part of the hydrogen atoms bonded to the ring is a group consisting of an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a phenyl group, a substituted phenyl group, and a combination thereof. May be substituted by a substituent selected from The wholly aromatic polyester generally exhibits a logarithmic viscosity of at least 2.0 dl / g, for example, 2.0 to 10.0 dl / g when dissolved in pentafluorophenol at a temperature of 60 ° C. at a concentration of 0.3 W / V%.

(D) a polyester consisting essentially of the following repeating units I, II, VII and VIII: (Wherein Ar represents a divalent group containing at least one aromatic ring) (Wherein Ar is the same as described above). The polyester has about 20 to 40 mol% of unit I,
II in an amount of more than about 10 mol%, not more than about 50 mol%, unit VII in an amount of more than about 5 mol%, not more than about 30 mol%, and unit VIII in an amount of more than 5 mol%, not more than about 30 mol%. I do. The polyester preferably comprises about 20 to 30 mole% of unit I, for example about 25 mole%, and unit II for about 25 to 40 mole%, for example,
About 35 mol%, about 15 to 25 mol% of the unit VII, for example, about 20
Mol VIII, and about 15 to 25 mol%, for example, about 20 mol%.
Mol%. Further, at least a part of the hydrogen atoms bonded to the ring is an alkyl group having 1 to 4 carbon atoms,
And 4 may be substituted with a substituent selected from the group consisting of an alkoxy group, a halogen atom, a phenyl group, a substituted phenyl group, and combinations thereof.

Units VII and VIII may have one or two divalent bonds linking these units to other units on either side of the polymer backbone.
It is preferable to be symmetrical in the sense that they are symmetrically arranged on the above aromatic ring (for example, when they are present on a naphthalene ring, they are arranged in a para position or on a diagonal ring). . However, asymmetric units such as those derived from resorcinol and isophthalic acid can also be used.

Preferred dioxyaryl units VII are And a preferred dicarboxyaryl unit VIII is It is.

(E) a polyester consisting essentially of the following repeating units I, VII, VIII: (Wherein Ar is as defined above) (Wherein Ar is the same as described above). The polyester has a unit I of about 10 to 90 mol%,
It contains 5 to 45 mol% of VII and 5 to 45 mol% of unit VIII. The polyester preferably has units I of about
20-80 mol%, about 10-40 mol% of unit VII and unit VIII
About 10 to 40 mol%. More preferably, the polyester contains about 60-80 mol% of unit I, about 10-20 mol% of unit VII, and about 10-20 mol% of unit VIII. At least a part of the hydrogen atoms bonded to the ring is selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a phenyl group, a substituted phenyl group, and a combination thereof. It may be substituted with a selected substituent.

Preferred dioxyaryl units VII are And a preferred dicarboxyaryl unit VIII is It is.

(F) a polyesteramide consisting essentially of the following repeating units I, IX, X and VII: (Wherein A represents a divalent group containing at least one aromatic ring or a divalent trans-cyclohexane group) General formula Y-Ar-Z X (wherein, Ar is as defined above). Y is O, NH or NR, Z is NH
Or NR, and R represents an alkyl group or an aryl group having 1 to 4 carbon atoms.) A unit represented by the general formula O-Ar-O VII (wherein Ar is as defined above) Oxyaryl Units The polyesteramide contains about 10-90 mol% of unit I, 5-45 mol% of unit IX, 5-45 mol% of unit X, and about 0-40 mol% of unit VII. I do. At least a part of the hydrogen atoms bonded to the ring has 1 to 1 carbon atoms.
It may be substituted by a substituent selected from the group consisting of an alkyl group having 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a phenyl group, a substituted phenyl group, and combinations thereof.

Preferred dicarboxyaryl units IX are And a preferred unit X is And a preferred dioxyaryl unit VII is It is.

Further, in the polymer forming the anisotropic melt phase of the present invention, a part of one polymer chain is composed of a segment of the polymer forming the anisotropic melt phase, and the remaining part is anisotropic melt phase. Also, a polymer composed of a segment of a thermoplastic resin that does not form a polymer is included.

The heat distortion temperature of the liquid crystalline polymer is usually 80 to 400
° C, preferably about 120 to 350 ° C, and is excellent in heat resistance. In particular, a liquid crystalline polymer having a heat deformation temperature of 150 to 250 ° C. is preferable because of excellent film-forming properties. The liquid crystalline polymer film has a water vapor transmission rate of about 0.1 g / m ²・ 100 μm ・ 24 hours ・ atmospheric pressure or less, and is excellent in moisture resistance, and has oxygen gas and carbon dioxide gas permeability of 1.0 cc / m ²・ 25 μm ・ 24 Less than time and pressure,
Excellent gas barrier properties. Temperature 70 ° C, relative humidity 96%
Even if it is left for 500 hours, it changes only about 0.003-0.02%,
Excellent dimensional stability.

The liquid crystalline polymer is contained in the liquid crystalline polymer film in at least 50% by weight, preferably 75% by weight or more.

The melt-processable polymer composition that forms the anisotropic melt phase used in the present invention includes other polymers that form the anisotropic melt phase, thermoplastic resins that do not form the anisotropic melt phase, and thermosetting. It may contain at least one of a resin, a low molecular organic compound, and an inorganic substance. The polymer forming the anisotropic molten phase in the composition and other components may be thermodynamically compatible.

As the above thermoplastic resin, for example, polyethylene, polypropylene, polybutylene, polybutadiene,
Polyisoprene, polyvinyl acetate, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer,
Ethylene-methacrylic acid ester copolymer, ionomer, polyvinyl chloride, polyvinylidene chloride, polystyrene, acrylic resin, ABS resin, AS resin, BS resin, polyurethane, silicone resin, fluororesin, polyacetal, polycarbonate, polyethylene terephthalate,
Polybutylene terephthalate, aromatic polyester, polyamide, polyacrylonitrile, polyvinyl alcohol, polyvinyl ether, polyetherimide, polyamideimide, polyetheretherimide, polyetheretherketone, polyethersulfone, polysulfone, polyphenylene sulfide, polyphenylene oxide, etc. included.

Examples of the thermosetting resin include a phenol resin, an epoxy resin, a melamine resin, a urea resin, an unsaturated polyester resin, a diallyl phthalate resin, and an alkyd resin.

Examples of the low-molecular-weight organic compound include, for example, substances usually added to thermoplastic resins and thermosetting resins, that is, weathering and light-resistant stabilizers such as plasticizers, antioxidants and ultraviolet absorbers, antistatic agents, Flame retardants, coloring agents such as dyes and pigments,
It includes a foaming agent, a divinyl compound, a crosslinking agent such as a peroxide and a vulcanizing agent, and a low molecular weight organic compound used as a lubricant for improving fluidity and releasability.

Further, as the above-mentioned inorganic substance, for example, a substance usually added to a thermoplastic resin and a thermosetting resin, that is,
General inorganic fibers such as glass fiber, carbon fiber, metal fiber, ceramic fiber, boron fiber, asbestos, calcium carbonate, highly dispersible silica, alumina, aluminum hydroxide,
Powdered substances such as talc powder, mica, glass flakes, glass beads, quartz powder, quartz sand, various metal powders, carbon black, barium sulfate, calcined gypsum and the like, and inorganic compounds such as silicon carbonate, boron nitrite and silicon nitride, Whiskers and metal whiskers are included.

The thermoplastic polymer having an adhesive property to the liquid crystal polymer layer is one that adheres to the liquid crystal polymer layer in a molten state and a cooled and solidified state. As such an adhesive thermoplastic polymer, a modified polyolefin, a modified polyester or the like is preferable. Modified polyolefin,
Modified polyester does not thermally decompose during extrusion,
Those having a film forming ability are used.

The modified polyolefin is preferably a modified polyolefin into which at least one functional group selected from a carboxy group, a glycidyl group, and an alkoxysilane group has been introduced. Further, the modified polyolefin may have, for example, a hydroxyl group, an alkoxy group, an alkoxycarbonyl group, an amino group, and the like. These functional groups may be used in combination. Examples of such a modified polyolefin include carboxy-modified polyolefin, glycidyl-modified polyolefin, alkoxysilane-modified polyolefin, carboxy-modified ethylene-ethyl acrylate copolymer, glycidyl-modified ethylene-ethyl acrylate copolymer, alkoxysilane-modified ethylene- Examples thereof include an ethyl acrylate copolymer, a carboxy-modified ethylene-vinyl acetate copolymer, a glycidyl-modified ethylene-vinyl acetate copolymer, and an alkoxysilane-modified ethylene-vinyl acetate copolymer.

The carboxy-modified, glycidyl-modified, and alkoxysilane-modified include, for example, acrylic acid, unsaturated carboxylic acid such as maleic anhydride or an acid anhydride thereof; glycidyl acrylate, a polymerizable unsaturated compound having a glycidyl group such as glycidyl methacrylate; It means that it has been modified with a polymerizable unsaturated compound having an alkoxysilane group such as methacryloxypropyltrimethoxysilane.

Further, the polyester has a polyvalent carboxylic acid, a polyhydric alcohol, a hydroxycarboxylic acid as a component,
If necessary, small amounts of monohydric carboxylic acids and monohydric alcohols are used.

As polyvalent carboxylic acids, divalent or higher carboxylic acids, for example, oxalic acid, maleic acid, maleic anhydride, succinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanoic acid and the like Polyvalent carboxylic acid; alicyclic polycarboxylic acid such as 1,4-cyclohexanedicarboxylic acid; phthalic acid, phthalic anhydride, terephthalic acid, isophthalic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride Examples thereof include aromatic polycarboxylic acids such as melitic acid, trimesic acid, naphthalene-2,6-dicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, and 3-sulfoisophthalic acid. These polycarboxylic acids can be used as a mixture of one or more kinds. In the present invention, a modified polyester is used in which the terephthalic acid is 30 to 80 mol% and the polycarboxylic acid selected from adipic acid, sebacic acid and isophthalic acid is 70 to 20 mol% among the above polycarboxylic acids. .

As the polyhydric alcohol, dihydric or higher alcohols, for example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, trimethylene glycol, 1,4-butanediol Aliphatic polyhydric alcohols such as 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, glycerol, trimethylolpropane, and pentaerythritol; resorcinol, 2,2-bis ( 4-hydroxyphenyl) propane, 4,4'-bis (2-hydroxyethyl) phenyl-2,2-propane, 4,4'-bis (2-hydroxypropyl) phenyl-2,2-propane, 4,4 '-Bis (2-hydroxyeth Shiechiru) aromatic polyhydric alcohols such as phenyl-2,2-propane and the like. These polyhydric alcohols can be used by mixing one or more kinds. Among the above polyhydric alcohols, ethylene glycol and 1,4-butanediol, particularly 1,4-butanediol, are preferred.

Examples of the hydroxycarboxylic acid include aliphatic hydroxycarboxylic acids such as glycolic acid and oxypropionic acid; and aromatic hydroxycarboxylic acids such as hydroxybenzoic acid, which may be used in combination of one or more.

Incidentally, the polyester referred to here, other polymers having a component of the polyester as a segment component,
For example, polyester ether, polyester amide,
Polyester carbonate and the like are also included.

In addition, from the viewpoint of the adhesive workability of the film and the like, among the above-mentioned adhesive thermoplastic polymers, a polymer exhibiting heat sealability and hot melt adhesiveness is preferable.

These adhesive thermoplastic polymers are used alone or in combination of two or more.

The thermoplastic polymer having no adhesiveness to the liquid crystalline polymer layer is one that does not exhibit adhesiveness to the liquid crystalline polymer layer in a molten state and a cooled and solidified state. A non-adhesive thermoplastic polymer that does not thermally decompose during extrusion and has a film-forming ability is used. Examples of such non-adhesive thermoplastic polymer include, for example, olefin-based polymers, polyalkylene terephthalate and polycarbonate, polyamide, polyarylate, polyacetal, polyetherimide, polyetheretherketone, polyethersulfone, polysulfone, polyphenylenesulfide, Polymers such as polyphenylene ether can be used.

As the olefin polymer, polyethylene,
Polypropylene, ethylene-propylene copolymer, poly-4-methylpentene-1, ionomer, ethylene-
Examples thereof include an ethyl acrylate copolymer and an ethylene-vinyl acetate copolymer. Among these polyolefin-based films, polyethylene, particularly high-density polyethylene, medium-density polyethylene, polypropylene and ethylene-propylene copolymer are preferred.

As the polyalkylene terephthalate, C2-C2
Those having about 6 alkylene groups, those having a cycloalkylene group or an ether group in a part of the above alkylene groups, particularly polyethylene terephthalate or polyalkylene terephthalate, for example, a part of ethylene glycol is 1,4-cyclohexanediene So-called PET-G and polybutylene terephthalate substituted with methanol, diethylene glycol or the like are preferred.

These non-adhesive thermoplastic polymers are used alone or as a mixture of two or more.

Further, the adhesive thermoplastic polymer and the non-adhesive thermoplastic polymer are contained in the adhesive thermoplastic polymer layer and the non-adhesive thermoplastic polymer layer in at least 50% by weight, preferably 75% by weight or more, and the thermoplastic resin, It may contain low molecular organic compounds, tackifiers, waxes and other inorganic substances.

Then, the liquid crystalline polymer, the adhesive thermoplastic polymer and the non-adhesive thermoplastic polymer are each melted and extruded by an extruder, and the coextruder is used to form an adhesive thermoplastic polymer on one side of the liquid crystalline polymer layer. Form a layer,
Extrusion is performed in a state where a non-adhesive thermoplastic polymer layer is formed on the other side, that is, in a state where an adhesive thermoplastic polymer layer and a non-adhesive thermoplastic polymer layer are formed via a liquid crystal polymer layer.

The above-mentioned co-extrusion molding machine is not particularly limited as long as it is an apparatus capable of co-extrusion molding in multiple layers. Examples of the co-extrusion molding machine include a multi-manifold die, a feed block system I in which a feed block and a single-layer die are combined, a feed block system II in which a feed block and a multi-manifold die are combined, and a Bain die of Clauren. As described above, an apparatus or the like that can perform coextrusion molding by providing a difference in the molding temperature of the polymer forming each layer of the multilayer film can be used. In addition, the feed block is Dow in the United States,
This is an apparatus for laminating a molten polymer in a co-extruded multilayer film manufacturing apparatus sold by Eagan Co., Ltd., Kloren Co., etc.

Hereinafter, a method for producing a laminated film of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic view showing an example of a method for producing a laminated film of the present invention. In this example, an example of producing a laminated film having a two-layer structure by using the co-extrusion molding apparatus of the feed block system I is shown. I have.

First, a liquid crystalline polymer is melted and extruded by an extruder (not shown), and supplied to a feed block (4) through a feed pipe (1) connected to the extruder. Further, the adhesive thermoplastic polymer is melted and extruded by an extruder (not shown) and supplied to one side of the liquid crystal polymer layer in the feed block (4) through the feed pipe (2). The non-adhesive thermoplastic polymer is supplied to the other side of the liquid crystalline polymer layer through the feed pipe (3) in the same manner as described above. In the feed block (4), the respective molten polymers merge at the junction of the three flow paths, and the liquid crystal polymer layer is used as an intermediate layer,
A molten polymer having a three-layer structure in which an adhesive thermoplastic polymer layer is laminated on one surface of the liquid crystalline polymer layer and a non-adhesive thermoplastic polymer layer is laminated on the other surface. The molten polymer is supplied to a single-manifold T-die (5) connected to a feed block (4), that is, a single-layer die, and extruded into a film.

The film (6) having a three-layer structure extruded from the T die (5) is cooled by a cooling roll (7) and pressed by a pressing roll (8) arranged opposite to the cooling roll (7). While winding, take up with the winding roll (10). At this time, the non-adhesive thermoplastic polymer layer (9) is peeled before reaching the take-up roll (10), whereby an adhesive thermoplastic polymer layer is formed on one surface of the liquid crystal polymer layer. The resulting laminated film is obtained.

FIG. 2 is a schematic view showing another example of the method for producing a laminated film of the present invention. In this example, an example is shown in which two laminated films having a two-layer structure are produced simultaneously. That is, the non-adhesive thermoplastic polymer is supplied to the first flow path (11) of the feed block (14) by an extruder (not shown), and the liquid crystalline polymer is supplied to the feed block by an extruder (not shown). (14) is supplied to second flow paths (12a) (12b) formed on both sides of the first flow path (11), and the adhesive thermoplastic polymer is extruded by an extruder (not shown). The water is supplied to third flow paths (13a) (13b) formed on both sides of the second flow paths (12a) (12b). At the junction of the five flow channels, the respective molten polymers merge to form a five-layered molten polymer. In this example, the second flow path (12a) (1
2b) and the third flow path (13a) (13b) are connected to the selector plug (15a) (15b) mounted on the feed block (14).
Are connected to each other by switching the flow path. The selector plug (15a) (15b) is switched to the second
This is an apparatus that can communicate the flow paths (12a) (12b) and the third flow paths (13a) (13b) in any combination.

Next, the molten polymer having a five-layer structure is supplied to the T-die (16) in the same manner as described above, and extruded into a film.
The film (17) having a five-layer structure extruded from is wound by two winding rolls (18a) and (18b) in the same manner as described above. At this time, the non-adhesive thermoplastic polymer layer (19) constituting the intermediate layer of the film is wound on the winding roll (18a) (1).
By peeling before reaching 8b), two laminated films having an adhesive thermoplastic polymer layer formed on one surface of the liquid crystalline polymer layer can be obtained at the same time.

When the non-adhesive thermoplastic polymer layer is peeled off after forming a multilayer film by co-extrusion in this way, the properties of the laminated film can be significantly improved. More specifically, when the liquid crystalline polymer alone is formed into a film, the outer skin of the liquid crystalline polymer film is peeled off due to the frictional force of the lip at the tip of the die, and the uniformity of the film is reduced. When extruded in a laminated state interposed between the thermoplastic polymer layer and the non-adhesive thermoplastic polymer layer, a film having excellent uniformity is obtained. In addition, the liquid crystal polymer film has a significantly reduced strength in the TD direction as described above, but since the liquid crystal polymer layer is laminated in an integrated state with the adhesive thermoplastic polymer layer, the strength in the TD direction is reduced. Not only does not decrease, but also it can be easily stretched in a uniaxial or biaxial direction, and the strength of the laminated film can be remarkably increased. Furthermore, since the heat-sealing property and hot-melt adhesive property can be ensured by the adhesive thermoplastic polymer layer of the obtained laminated film, it can be used as various packaging films.

In addition, using a co-extrusion molding machine, for example, a co-extrusion molding machine having a large number of flow paths as shown in FIG. 2, changing the type of polymer supplied to each flow path, or using an extruder communicating with each flow path Laminated films having various lamination forms can be manufactured by adjusting an appropriate number of connections or adjusting the flow paths communicating with each other by the selector plug.

FIG. 3 is a schematic cross-sectional view showing one laminated form of the laminated film obtained by the production method of the present invention, and FIG.
As shown in FIG. 3, an adhesive thermoplastic polymer layer (22) may be laminated on one side of the liquid crystal polymer layer (21), and as shown in FIG. 3 (B), the liquid crystal polymer layer (31) A plurality of adhesive thermoplastic polymer layers (32a) (32b) may be laminated on one side of the substrate.

Further, as shown in FIG. 3 (C), an adhesive thermoplastic polymer layer (4) is formed on one side of the liquid crystalline polymer layer (41).
2) Via heat sealability, hot melt adhesion,
A non-adhesive thermoplastic polymer layer (43) having excellent gas barrier properties and heat resistance may be formed. As shown in FIG. 3 (D), one surface of the liquid crystal polymer layer (51) Through a plurality of adhesive thermoplastic polymer layers (52a) (52b),
A non-adhesive thermoplastic polymer layer (53) excellent in heat sealability or hot melt adhesiveness may be formed. Further, as shown in FIG. 3 (E), an adhesive thermoplastic polymer layer (62) is formed on one surface of the liquid crystalline polymer layer (61).
a) through a non-adhesive thermoplastic polymer layer (63);
The adhesive thermoplastic polymer layer (62b) may be sequentially formed. As shown in FIG. 3 (D), when a plurality of adhesive thermoplastic polymer layers (52a) and (52b) are laminated, each of the adhesive thermoplastic polymer layers (52a) and (52b) forms a liquid crystal polymer layer (52b). 51) and non-adhesive thermoplastic polymer layer (53)
Since the bonding function can be shared, the bonding strength can be increased.

The non-adhesive thermoplastic polymer layer (43) (53)
Is composed of a non-adhesive thermoplastic polymer having a heat seal property or a hot melt adhesive property, for example, the olefin polymer, it is possible to further enhance the water vapor barrier property and secure the heat seal property. Therefore, a bag can be easily formed by pillow packaging, a four-sided sheet, or the like. Non-adhesive thermoplastic polymer layer (43) (53)
When (63) is composed of a polyalkylene terephthalate, for example, the above-mentioned polybutylene terephthalate, PET-G or the like, a gas barrier property such as an oxygen gas barrier property can be enhanced, and a film having excellent heat resistance can be obtained.

The laminating form of the laminated film is not limited to the structure shown in FIG. 3, but it is sufficient that at least one adhesive thermoplastic polymer layer is laminated on one surface of the liquid crystalline polymer layer. it can. For example, a liquid crystal polymer layer, an adhesive thermoplastic polymer layer, and a non-adhesive thermoplastic polymer layer as necessary may be formed of a plurality of layers, and a liquid crystal polymer layer and an adhesive thermoplastic polymer layer may be formed. They may be alternately stacked.

Although the number of layers of the laminated film is not particularly limited, it is usually about 2 to 11 layers, preferably 2 to 9 layers.

The extrusion temperature of the liquid crystalline polymer can be appropriately set according to the type and the like, and is usually a temperature equal to or higher than the softening point of the polymer. For example, the preferred liquid crystalline polymer is extruded at a temperature of usually about 200 to 400 ° C, preferably about 240 to 340 ° C. Here, the softening point means the lowest temperature at which the liquid crystalline polymer can melt and flow. The extrusion temperature of the adhesive or non-adhesive thermoplastic polymer is preferably higher than (T-50) ° C., where T is the extrusion temperature of the liquid crystalline polymer. More preferably, the extrusion temperature of the liquid crystalline polymer is about ± 50 ° C.

Molding conditions such as the extrusion speed of each polymer, the temperature of the cooling roll, and the film take-up speed can be appropriately set according to the desired film characteristics.

Incidentally, the laminated film, roll stretching, belt stretching, tenter stretching, by a conventional stretching means such as tube stretching,
Uniaxial or biaxial stretching may be performed at an appropriate magnification.

The thickness of the laminated film obtained by the present invention is not particularly limited, but is preferably about 10 to 1000 μm. The thickness of the liquid crystalline polymer layer is usually 1 to 500 μm, preferably about 5 to 250 μm. The thickness of the non-adhesive thermoplastic polymer layer, the non-adhesive thermoplastic polymer layer to be peeled off, and the non-adhesive thermoplastic polymer layer laminated on the adhesive thermoplastic polymer layer is usually about 1 to 100 μm. .

In addition, the obtained laminated film has a corona discharge treatment,
Such as sputtering, high-frequency treatment, flame treatment, chromic acid treatment, solvent etching treatment, undercoat treatment,
A surface treatment combining these may be performed.

The laminated film obtained by the present invention has a liquid crystal polymer layer having excellent heat resistance, gas barrier properties, dimensional stability, and the like, and an adhesive thermoplastic polymer layer, and has excellent strength and adhesion in the TD direction. There are various packaging items,
It can be used as a film for interior, exterior and bag making. For example, retort foods, food packaging materials such as microwave oven foods, packaging materials for oily cooking materials, packaging materials for medicines, packaging materials for cosmetics, fragrance-retaining packaging materials for aromatic substances, etc., for example, desks,
It can be used for various uses such as a protective film for a laboratory bench.

[Effects of the Invention] As described above, according to the method for producing a laminated film of the present invention, the co-extrusion molding machine is used to have an adhesive property to the liquid crystal polymer layer via the liquid crystal polymer layer. After extruding in a state where a thermoplastic polymer layer and a thermoplastic polymer layer having no adhesiveness to the liquid crystalline polymer layer are formed, the thermoplastic polymer layer having no adhesiveness is peeled off,
And, since the modified polyolefin or modified polyester is used as the thermoplastic polymer having the adhesive property, the strength and adhesiveness in the TD direction are excellent while taking advantage of the excellent properties of the liquid crystalline polymer, which is suitable as a packaging film or the like. Films can be produced economically and industrially.

EXAMPLES Hereinafter, the present invention will be described in more detail based on examples.

Example 1 Using a coextrusion molding machine shown in FIG. 1, a liquid crystalline polymer (Vectra A900, manufactured by Polyplastics Co., Ltd., trade name: Vectra A900) composed of the repeating units I and II was melted. The polymer is supplied from a feed pipe (1), a molten polymer of glycidyl-modified polyethylene (Nippon Petrochemical Co., Ltd., Lexpearl J-3700) is supplied from a feed pipe (2), and polypropylene (Sumitomo Chemical Co., Ltd.) is supplied. ) Made, brand name Noblen FL6315G)
Was fed from the feed pipe (3).
In addition, the three-layered molten polymer is extruded from the T-die (5), and the polypropylene layer is peeled before reaching the take-up roll (10), and the laminated form as shown in FIG. , 10μm liquid crystalline polymer layer (21)
A laminated film having a 10 μm adhesive thermoplastic polymer layer (22) laminated thereon was produced.

Example 2 In place of the glycidyl-modified polyethylene and polypropylene of Example 1, an alkoxysilane-modified ethylene-ethyl acrylate copolymer (trade name, manufactured by Du Pont-Mitsui Co., Ltd.)
HPR AS252) and medium density polyethylene (manufactured by Mitsui Petrochemical Co., Ltd., trade name Neozex 3510F)
The polyethylene layer was peeled off in the same manner as in Example 1 above, and the laminated form as shown in FIG. 3 (A), that is, a 10 μm liquid crystal polymer layer (21) and a 10 μm adhesive thermoplastic polymer layer (22) was laminated to produce a laminated film.

Example 3 Instead of the glycidyl-modified polyethylene and polypropylene of Example 1, a glycidyl-modified ethylene-vinyl acetate copolymer (manufactured by Sumitomo Chemical Co., Ltd., trade name Bonfast 7B) and polyethylene terephthalate (manufactured by Unitika Ltd.) Example 1 except that the intrinsic viscosity was 0.65).
The polyethylene terephthalate layer was peeled off in the same manner as described above, and a laminated form as shown in FIG. 3 (A), that is, a 10 μm liquid crystal polymer layer (21) and a 10 μm adhesive thermoplastic polymer layer (22) Were laminated to obtain a laminated film.

Example 4 The procedure of Example 1 was repeated, except that the glycidyl-modified polyethylene of Example 1 was replaced with an acrylic acid ester-maleic anhydride-modified polyethylene (trade name: Bondine AX8060, manufactured by Sumitomo Chemical Co., Ltd.). Fig. 3 (A)
, Ie, a laminated film in which a 10 μm liquid crystalline polymer layer (21) and a 10 μm adhesive thermoplastic polymer layer (22) were laminated.

Example 5 In place of the glycidyl-modified polyethylene of Example 1, a polyester (manufactured by Toyobo Co., Ltd., trade name Byron GM-900) was used.
In the same manner as in Example 1 except for using a liquid crystal layer, a laminated form as shown in FIG. 3A, that is, a 10 μm liquid crystal polymer layer (21) and a 10 μm adhesive thermoplastic polymer layer (22) were formed. A laminated film was produced.

Example 6 In place of the polyester of Example 5, another polyester (trade name: ARONMELT PES-140, manufactured by Toagosei Chemical Co., Ltd.)
Except for using H), in the same manner as in Example 1, a laminated form as shown in FIG. 3A, that is, a 10 μm liquid crystal polymer layer (21) and a 10 μm adhesive thermoplastic polymer layer (22) ) To produce a laminated film.

Example 7 In the same manner as in Example 1 except that a polyester (manufactured by Toray Industries, Inc., Chemit R50) was used instead of the polyester of Example 5, a laminated form as shown in FIG.
That is, a laminated film in which a 10 μm liquid crystalline polymer layer (21) and a 10 μm adhesive thermoplastic polymer layer (22) were laminated was produced.

Example 8 Using the co-extrusion molding machine shown in FIG. 2 to which four extruders were connected, without supplying the polymer to the channel (11) by the selector plugs (15a) and (15b), The liquid crystalline polymer is supplied to the channel (12a), the polypropylene of Example 1 is supplied to the channel (13a), the glycidyl-modified polyethylene of Example 1 is supplied to the channel (12b), and one of the glycol components is supplied. Polyethylene terephthalate (PET-
G) (manufactured by Eastman Chemical Products, trade name: PETG5116) was supplied to the channel (13b). Further, the molten polymer having a four-layer structure is extruded from the T-die (16), and the polypropylene layer is peeled before reaching the one take-up roll (18a) shown in FIG. 2 and wound around the take-up roll (18a). By taking, as shown in FIG.
On one side of the liquid crystal polymer layer (41) of μm, a non-adhesive thermoplastic polymer layer (43) of 10 μm made of PET-G is laminated via an adhesive thermoplastic polymer layer (42) of 5 μm. A laminated film was produced.

Example 9 Using the co-extrusion molding machine shown in FIG. 2 to which four extruders were connected, the flow path was adjusted by the selector plugs (15a) and (15b) to flow the liquid crystalline polymer of Example 1. The polypropylene was supplied to the channel (12a), the polypropylene of Example 1 was supplied to the channel (13a), and the alkoxysilane-modified ethylene-ethyl acrylate copolymer of Example 2 was supplied to the channel (11). In addition, polybutylene terephthalate (PBT) (manufactured by Polyplastics Co., Ltd.
1.0 dl / g of intrinsic viscosity measured at a temperature of 25 ° C.) was supplied to the channel (12b), and the glycidyl-modified polyethylene of Example 1 was supplied to the channel (13b). Further, the five-layered molten polymer is extruded from the T-die (16), and the polypropylene layer is peeled before reaching the one take-up roll (18a) shown in FIG. 2 and wound around the take-up roll (18a). Then, as shown in FIG. 3 (E), a 5 μm adhesive thermoplastic polymer layer (62a) and a 10 μm non-adhesive layer made of PBT are formed on one surface of the 10 μm liquid crystal polymer layer (61). A laminated film was formed by sequentially laminating a thermoplastic thermoplastic polymer layer (63) and a 10 μm thermoplastic polymer layer (62b).

Example 10 Using the co-extrusion molding machine shown in FIG. 2, the polypropylene of Example 1 was supplied to the channel (11), and the liquid crystalline polymer of Example 1 was supplied to the channels (12a) and (12b). Then, the alkoxysilane-modified ethylene-ethyl acrylate copolymer of Example 2 was supplied to the channels (13a) and (13b), respectively. In addition, a 5-layered molten polymer is extruded from a T-die (16),
As shown in FIG. 2, the non-adhesive thermoplastic polymer layer (1
9) The polypropylene layer is peeled off and wound up on winding rolls (18a) and (18b), respectively.
As shown in FIG. 3 (A), two laminated films in which a 10 μm adhesive thermoplastic polymer layer (22) was laminated on one surface of a 10 μm liquid crystalline polymer layer (21) were simultaneously produced.

Comparative Example 1 The liquid crystalline polymer of Example 1 was formed into a film having a thickness of 30 μm using a usual T-die extruder.

Comparative Example 2 The liquid crystal polymer of Example 1 and the polypropylene of Example 1 were extruded using a common co-extrusion molding machine, and a 10 μm liquid crystal polymer layer and a 10 μm polypropylene layer were co-extruded, but adhered to each other. Thus, the liquid crystalline polymer layer and the polypropylene layer were easily peeled off, and it was difficult to form a composite. Also, the use of the feed-block type co-extrusion molding machine shown in FIG. 1 did not produce a composite film in the same manner as described above. Therefore, the obtained film was not subjected to the following tests.

Then, the tensile strength in the TD direction of the film and the MD direction perpendicular to the TD direction were measured, and the oxygen gas permeability and the water vapor permeability were measured under the following conditions. The results shown in the table were obtained.

ASTM D-3985- using a carrier gas consisting of 98% nitrogen gas and 2% hydrogen gas under the conditions of oxygen gas permeability of 23 ° C and relative humidity of 60%.
It was measured by the isobaric method according to No.81.

Water vapor transmission rate Measured using an infrared sensor according to ASTM F-372-73 under the conditions of a temperature of 25 ° C. and a relative humidity of 90%, using air as a carrier gas.

As is clear from the table, the film of Comparative Example 1 was extremely weak in the TD direction, was easily torn, and could not be heat-sealed or dry-laminated.
In addition, the film of Comparative Example 2 did not show adhesion to each other, wasting material, and was not economical.

In contrast, each of the laminated films of the examples was
It has excellent strength in the TD direction and gas barrier properties, and can be dry-laminated with a polybutylene terephthalate film or polyethylene terephthalate film using an adhesive thermoplastic polymer layer, and can be easily made into a packaging bag by heat sealing. it can. In the case of Example 8, a bag could be produced by heat sealing with the PET-G layer.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of a method for producing a laminated film of the present invention, FIG. 2 is a schematic diagram showing another example of a method for producing a laminated film of the present invention, and FIGS. 3 (A) and 3 (B) ( (C), (D), and (E) are schematic cross-sectional views each showing an example of the laminated form of the laminated film obtained by the method of the present invention. (21) (31) (41) (41) (51) (61): Liquid crystal polymer layer, (22) (32a) (32b) (42) (52a) (52b)
(62a) (62b) ... Adhesive thermoplastic polymer layer

Claims (1)

(57) [Claims] 1. A thermoplastic polymer layer having an adhesive property with respect to a liquid crystal polymer layer and a liquid crystal polymer layer having an adhesive property through a liquid crystal polymer layer using a co-extrusion molding machine. After extruding in the state of forming a non-adhesive thermoplastic polymer layer, the non-adhesive thermoplastic polymer layer is peeled off, and a method for producing a laminated film, wherein the thermoplastic polymer having the adhesive property includes a carboxy group , A glycidyl group, and a modified polyolefin into which at least one functional group selected from an alkoxysilane group has been introduced, or a polycarboxylic acid component containing 30 to 80 mol% of terephthalic acid and adipic acid, sebacic acid, and isophthalic acid. A method for producing a laminated film using a modified polyester composed of 70 to 20 mol% of a selected polycarboxylic acid.