JPH0848010A - Laminated film - Google Patents

Abstract

PURPOSE:To make surface hardness, abrasion resistance, scratch resistance, flexibility, surface uniformity and high speed curing properties excellent while reducing heat shrinkability, in a laminated film wherein a radiation curable layer is laminated on a base material film, by using a polyalkylene naphthalate film as the base material film. CONSTITUTION:In a laminated film wherein a radiation curable layer II is laminated on a base material film (I), a polyalkylene naphthalate film (e.g. polyethylene 2,6-naphthalate film) is used as the base material film. A molecularly oriented crosslinked modifying layer II is laminated between the base material film I and the radiation curable layer II. As a result, a laminated film excellent in surface hardness, abrasion resistance, scratch resistance, flexibility and surface uniformity, low in heat shrinkability, excellent in high curing properties, optically excellent from an aspect of transparency, whiteness, concealability and coloring properties, good in slip properties, excellent in processing aptitude and handling properties and extremely reduced in curl is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated film having a polyalkylene naphthalate film as a base material and a radiation curable resin laminated thereon. More specifically, the present invention relates to a laminated film having excellent surface hardness, abrasion resistance, scratch resistance, flexibility, surface uniformity, low heat shrinkage, high-speed curing property, and extremely small curl.

[0002]

2. Description of the Related Art Conventionally, a method of providing a radiation-curable layer has been known as a method for hardening the surface of a plastic film. In particular, a polyethylene terephthalate film provided with these layers generally has a radiation-curable reactive monolayer. There is a problem that curling occurs because the shrinkage rate of the polymer during curing is large. The surface hardness of the radiation curable layer is closely related to the thickness, and a thickness of a certain value or more is required to obtain a constant surface hardness, while curl is not noticeable when the radiation curable layer is thin, With this, a sufficient surface hardness cannot be obtained, and in order to obtain a sufficient surface hardness, there is a problem that a certain thickness or more is required and the curl becomes large.

[0003]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above problems and to provide excellent surface hardness, abrasion resistance, scratch resistance and flexibility, and further to reduce surface uniformity and heat shrinkage. It has excellent fast-curing properties, very little curl, excellent heat resistance and mechanical strength, and from transparent to white
The object of the present invention is to provide a laminated film which is optically excellent even in the concealing property.

[0004]

In order to achieve the above object, the present invention has the following constitution, namely, a laminated film obtained by laminating a radiation curable layer (II) on a base film (I), A laminated film, wherein the base film (I) is a polyalkylene naphthalate film.

The material of the base film of the present invention is polyalkylene naphthalate, and the polyester film is a general term for polymer films having an ester bond as a main bonding chain of the main chain. Particularly preferred polyesters are:
Polyethylene 2,6-naphthalate, polyethylene α,
β-bis (2-chlorophenoxy) ethane 4,4′-dicarboxylate, polybutylene 2,6-naphthalate and the like. Among them, polyethylene 2,6-naphthalate (hereinafter, PEN
It may be abbreviated as. ) Is most preferred. Known additives in the polyalkylene naphthalate, for example, heat resistance stabilizer, oxidation resistance stabilizer, weather resistance stabilizer, ultraviolet absorber, organic lubricant, pigment, organic or inorganic fine particles,
A release agent, an antistatic agent, a nucleating agent, etc. may be added.

The polyalkylene naphthalate film may be used in any of unoriented, uniaxially oriented and biaxially oriented directions, but a biaxially oriented film is preferable because it has excellent mechanical strength. The biaxially oriented film is produced by stretching an unstretched sheet or film in the so-called biaxial directions of the longitudinal direction and the width direction by about 2.5 to 5 times each.
Wide-angle X-ray diffraction indicates a biaxially oriented pattern.

The thickness of the base film is not particularly limited,
For example, from the waist strength required for a laminated film, 25
An appropriate thickness can be set within the range of about 500 μm.

The base film preferably has a heat shrinkage ratio at 150 ° C. of 0.5% or less. By thus suppressing the heat shrinkage rate of the base film to be low, it is possible to suppress wrinkles and curls in the laminated film even after the curable layer is cured and shrunk.

In the present invention, the base material film may be appropriately selected from optically transparent ones depending on the purpose and, if necessary, white ones or those having a hiding property. it can. So-called non-glare and white, hiding,
When a colored laminated film is desired, for example, a non-glare, white or hiding, coloring hardened layer is laminated on a transparent film support, or a non-glare, white or hiding, coloring film support is formed. It can be manufactured by laminating a transparent, non-glare, white, hiding and coloring hardened layer on the body.

The substrate film used in the present invention may be whitened by containing white inorganic particles in polyester. The white inorganic particles refer to known non-colored inorganic particles such as calcium carbonate, amorphous zeolite particles, titanium oxide, calcium phosphate, calcium sulfate, barium sulfate, silica, alumina, kaolin, talc and clay. . In addition to such inorganic particles, it is also possible to use fine particles deposited by the reaction of the catalyst residue and the phosphorus compound in the polyester polymerization reaction system.

In the present invention, the specific gravity of the base film is not particularly limited, but when a laminated film having a low specific gravity and excellent whiteness is desired, the specific gravity is 1.3 or less, preferably 1.2 or less. Are preferably used. When the base film is PEN film, its specific gravity is 1.3
In order to suppress it below, for example, a special device as described below is required.

First, when an incompatible polymer is dispersed and mixed in a PEN film, a void is formed around the incompatible polymer particularly when the PEN is stretched into a film, and the specific gravity can be suppressed to a low level by the same amount. , The film is whitened by numerous voids. The PEN film as the substrate film thus obtained has a lower specific gravity than the ordinary PEN film and has excellent whiteness and cushioning properties. The shape factor of the incompatible polymer to be dispersed and mixed in the film is preferably 1 to 4. The average equivalent spherical diameter of voids in the film formed of the incompatible polymer is 1 μm to 10 μm.
It is preferably μm.

The incompatible polymer is not particularly limited as long as it is a polymer incompatible with PEN, but is preferably methylbutene polymer, methylpentene polymer,
It is a polymer having a melting point of 200 ° C. or higher selected from styrene polymers, fluorine polymers, cellulose acetate and cellulose propionate polymers.

In order to keep the specific gravity of the base film low, the PEN film may be mixed with the above-mentioned incompatible polymer or separately from the incompatible polymer only for the purpose of lowering the specific gravity. It is also effective to include a low specific gravity agent. The low specific gravity agent is a compound having an effect of reducing the specific gravity by adding it to PEN, and the effect is recognized only in a specific compound. For example, the specific gravity reducing agent can be selected from polyalkylene glycols, ethylene oxide / propylene oxide copolymers, alkylbenzene sulfonates, alkyl sulfonates and modified products thereof, and copolymers thereof with polyesters.

In the polyalkylene naphthalate film of the present invention, the outermost layer on at least one side is a polyester layer (IV) in which inert particles are contained to form uniform unevenness on the surface, or depending on the particles. It is preferable that the layer (V) of polyester has desired fine projections formed on the surface thereof by utilizing the crystallization of the polyester, because the running property and the slip property are excellent, the processability and the handling property are further improved.

In, the thickness of the outermost layer (t μm)
And the average particle diameter (dμm) of the particles are in the range of 0.1 ≦ t / d ≦ 10, the particle content is 0.1 to 50% by weight, and the thickness of the outermost layer is 0.1. 005 to 3 μm and PEN
It is preferable to laminate a layer of polyester having as a main component. If t / d is larger or smaller than the above range, running property and slipperiness are likely to be deteriorated, which is not preferable. When the content of the particles is less than 0.1% by weight, running properties and slipperiness are apt to deteriorate, while when it exceeds 50% by weight, the film strength is apt to decrease, which are not preferable. The thickness of the outermost layer is 0.01
If it is less than μm, the running property and the slipperiness tend to be deteriorated, while 3μ
If it exceeds m, the film strength tends to decrease, which is not preferable. The outermost layer is preferably composed of ethylene naphthalate as a main constituent and 80% by weight or more of PEN, but a blend of PEN and another polyester,
Alternatively, it may be made of a copolymer of PEN and another polyester. Further, different polymers may be blended within a range that does not impair the object of the present invention, and organic additives such as antioxidants, heat stabilizers, lubricants, and ultraviolet absorbers are added to the extent that they are usually added. May be. The inert particles are not particularly limited, but are colloidal silica, calcium carbonate, titanium dioxide, alumina, crosslinked polymers (for example, crosslinked polystyrene), and the average particle size is 0.1 to 10 times the thickness of the outermost layer, preferably Is 0.5 to 5
It is desirable to be in the range of 1.2 times, more preferably 1.1 to 3 times. If it is smaller or larger than the above range, the running property tends to deteriorate, which is not preferable. The average particle diameter (diameter) in the outermost layer is 0.007 to 0.
5 μm is preferable, and more preferably 0.02 to 0.4
When the thickness is in the range of 5 μm, it is desirable that the running property and the like become better.

In most or all of the surface protrusions are formed by utilizing crystallization of polyester, the number of protrusions is 5 × 10 ³ / mm ² or more, and the number of protrusions and the surface are formed. It is preferable that the number of protrusions / the number of particles (N _R ), which is the ratio to the number of particles contained in the surface layer, is 5 or more. When N _R is less than 5, the proportion of protrusions formed by the contained particles increases, and the proportion of protrusions that are easily broken due to void formation accompanying particle addition increases, so that it becomes difficult to obtain desirable scratch resistance, Not preferable. The formation of surface protrusions utilizing the crystallization of polyester as described above is performed as follows. In producing a biaxially stretched film containing polyester as a main component, heat treatment is applied to at least one surface of the unstretched film,
Thereafter, the unstretched film is biaxially stretched to form desired surface protrusions. By first subjecting the unstretched film to heat treatment, crystallization of the surface of the unstretched film is promoted, and a large number of fine crystals are generated. This unstretched film is biaxially stretched, the film is biaxially oriented and the target strength of the film itself is achieved, and due to the difference in hardness between the crystal and the other part, the fine crystals cause A uniform fine surface protrusion is formed. Here, regarding whether or not the surface protrusions are made of polyester fine crystals, under the target protrusion,
Etching with an appropriate solvent in the film thickness direction,
When the substance that forms the protrusions remains as an insoluble substance, the particles are added from the outside or the particles are precipitated inside (X). When substantially nothing remains as an insoluble substance, it can be estimated that the substance that forms the protrusion is fine crystals (Y). As the above-mentioned solvent, for example, a mixed solvent of phenol / carbon tetrachloride (weight ratio: 6/4) is preferably used. By this method, the frequency of X and the frequency of Y when the visual field is set to about 1 mm ² are obtained, and it is preferable that the value of X / (X + Y) is 70% or more.
In the present invention, the type of polyester A is not particularly limited, but the crystallization parameter ΔTcg is preferably 70 ° C. or lower, more preferably 65 ° C. or lower, and further preferably 55 ° C. or lower. If the crystallization parameter ΔTcg is larger than 70 ° C., it is difficult to obtain the surface protrusions targeted by the present invention, which is not preferable. The polyester is not particularly limited as long as it satisfies the above conditions, but is particularly preferable when at least one structural unit selected from ethylene rephthalate and ethylene 2,6-naphthalate units is a main constituent component. In order to form the target surface protrusions, the film containing polyester as a main component is crystallized by heat treatment before biaxial stretching as described above, but is present in the unstretched film before biaxial stretching. The diameter r of the spherulites is preferably in the range of 0.03 to 0.45 μm. More preferably 0.10
It is in the range of 0.30 μm. By controlling in such a range, the scratch resistance of the film surface after biaxial stretching becomes excellent. The polyester film of the present invention may be used alone as a biaxially oriented film containing polyester as a main component, or may be used as a laminated film laminated on at least one side of a film containing PEN as a main component.

When the PEN film is a film which has been subjected to surface treatment by a known method, that is, corona discharge treatment (in air, nitrogen, carbon dioxide, etc.) or easy adhesion treatment, the adhesion to the coating layer, It can be used more preferably because the water resistance and chemical resistance are improved. For the easy-adhesion treatment, various known methods can be used, and those obtained by coating various known easy-adhesive agents on the film during the film production process or after uniaxially or biaxially stretching can be preferably used.

The film made of polyalkylene naphthalate used in the present invention is dissolved, emulsified or suspended in water and / or an organic solvent in order to improve the adhesion between the hardened layer and the polyalkylene naphthalate. An undercoat of acrylic resin, polyester resin, polyurethane resin or the like can be preferably used. In particular, a product obtained by undercoating a reaction product of a vinyl-based copolymer having a hydroxyl group and a partial ester group of phosphoric acid and a polyisocyanate compound (described in JP-B-58-35145), or a polyester resin containing a hydrophilic group and an acrylic resin. Undercoating a composition comprising a copolymer grafted with a compound and a cross-linking agent, undercoating a composition obtained by mixing these with a polyurethane resin, and the like, a film comprising a hardness layer and polyalkylene naphthalate The adhesiveness is improved, and it is preferable as a film excellent in durability such as moist heat resistance and boiling water resistance. Among these, the crosslinked modified layer (III) having a molecular orientation is most preferably used. Here, the molecular orientation means that the degree of molecular orientation obtained by the method described later is 0.01 or more. Due to the molecular orientation of the crosslinked modified layer, solvent resistance, water resistance, warm water resistance,
The alkali resistance is improved. In particular, when the degree of molecular orientation is preferably 0.02 to 0.40, and more preferably 0.05 to 0.20, the effect of improving the easy adhesion is large and the cleavage in the crosslinked modification layer (III) is less likely to occur. Is particularly preferable in terms of. When the presence of the hydrophilic group-containing polyester resin measured by the ESCA method within 100 angstroms from the surface layer of the crosslinked modified layer (III) is below the detection limit, that is, the resin layer constituting the surface layer is composed of an acrylic compound and a crosslinking agent. In this case, the effects of the present invention are more remarkably exhibited, which is particularly preferable. Examples of the crosslinked modified layer of the crosslinked modified layer (III) having such a molecular orientation include, for example, a copolymer obtained by grafting at least one acrylic compound onto a hydrophilic group-containing polyester resin, and a crosslinked bond. Those comprising a composition containing an agent as a main component are particularly preferably used. Here, the main component means that the main component occupies 80% by weight or more. Examples of such a crosslinked modified layer (III) include Japanese Patent Application No. 1-8633.
Those described in No. 3 can be preferably used. Also, if necessary, known NO additives such as defoaming agents, coating improvers, thickeners, antistatic agents, antioxidants, ultraviolet absorbers, dyes, pigments, etc., within a range that does not impair the effects of the present invention. May be contained, or fine particles of an inorganic or organic compound may be contained as a lubricant. Crosslinked modified layer (II
The laminated thickness of I) is not particularly limited, but is usually 0.02 to
1.0 μm is preferable, and more preferably 0.05 to
The range is preferably 0.5 μm.

In the present invention, three or more (meth) acryloyloxy groups in one molecule (here, the (meth) acryloyloxy group is an abbreviation for an acryloyloxy group and a methacryloyloxy group). In the range below and in the following explanation, △△△ (meta) □□□
Similarly, ΔΔΔ □□□ and ΔΔΔ meta □□□ are all abbreviated. 1) as a monomer (A) having
Examples of the compound include a polyhydric alcohol having 3 or more alcoholic hydroxyl groups in the molecule, and 3 or more (meth) acrylic acid hydroxyl groups of the polyhydric alcohol.
B curing handbook (raw materials) "(Kiyomi Kato, Polymer Publishing, 1985) and" Applications and markets of UV and EB curing technology "(supervised by Yoneho Tabata, edited by Radtech Research Group, CMC, 1989). It can be used by selecting it from the publicly known ones described in.

Specific examples include pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth). ) Acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate and the like.

These monomers (A) may be used either individually or in combination of two or more.

The proportion of these monomers (A) used is preferably 20 to 90% by weight, more preferably 30 to 80% by weight, based on the total amount of the polymerizable monomers. When the amount of the monomer (A) is less than 20% by weight, a cured coating having sufficient abrasion resistance cannot be obtained, and when the amount exceeds 90% by weight, it is cured by shrinkage due to polymerization. This is not preferable because the strain remains in the film and the flexibility of the film itself is extremely reduced.

As the monomer having 1 to 2 ethylenically unsaturated double bonds in one molecule in the present invention, any ordinary monomer having radical polymerization activity can be used. It can be appropriately used by selecting it from publicly known ones described in books and the like.

Examples of the compound having two ethylenically unsaturated double bonds in the molecule include the following (meth) acrylates (a) to (g).

(A) (Meth) acrylic acid diester of alkylene glycol having 2 to 12 carbon atoms: ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate , Neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, etc. (b) (meth) acrylic acid diesters of polyoxyalkylene glycol: diethylene glycol di (meth)
(C) Polyhydric alcohol (meth) acrylic acid, such as acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate Diesters: pentaerythritol di (meth) acrylate, etc. (d) Bisphenol A, bisphenol S or bisphenol A, (meth) hydrides of ethylene oxide and propylene oxide adducts of hydrides of bisphenol S
Acrylic acid diesters: 2,2′-bis [4- (meth) acryloxyethoxyphenyl] propane, 2,
2'-bis [4- (meth) acryloxypropoxyphenyl] propane, etc., and (e) a diisocyanate compound and two or more alcoholic hydroxyl group-containing compounds are further alcoholic to the terminal isocyanate group-containing compound obtained by previously reacting Urethane (meth) acrylates having two or more (meth) acryloyloxy groups in the molecule obtained by reacting a hydroxyl group-containing (meth) acrylate: (f) a compound having two or more epoxy groups in the molecule Epoxy (meth) acrylates having two or more (meth) acryloyloxy groups in the molecule obtained by reacting acrylic acid or methacrylic acid: (g) Two (meth) acrylates in one molecule having a tricyclo ring structure. ) (Meth) acrylates having a tricyclo ring structure having an acryloyloxy group: tri Examples thereof include cyclodecane dimethanol diacrylate.

Examples of the compound having one ethylenically unsaturated double bond in the molecule include methyl (meth) acrylate, ethyl (meth) acrylate, n- and i-butyl (meth) acrylate and 2-ethylhexyl (meth). )
Acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, hydroxyethyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate , Glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, N-hydroxyethyl (meth) acrylamide, N-vinylpyrrolidone, N-vinyl-3-methylpyrrolidone, N-vinyl-5-methylpyrrolidone and the like. .

These monomers (B) may be used either individually or in combination of two or more.

The proportion of these monomers (B) used is preferably 10 to 80% by weight, more preferably 20 to 70% by weight, based on the total amount of the monomers. When the amount exceeds 80% by weight of the monomer (B), it is difficult to obtain a crosslinked cured coating having sufficient abrasion resistance, which is not preferable. On the other hand, if the amount is less than 10% by weight, the flexibility of the film is lowered and the adhesion to the substrate is lowered, which is not preferable.

One method for curing the radiation-curable composition of the present invention is irradiation with ultraviolet rays. In this case, it is preferable to add a photopolymerization initiator to the composition. Specific examples of the photopolymerization initiator include acetophenone, 2,2-diethoxyacetophenone, p-
Dimethylacetophenone, p-dimethylaminopropiophenone, benzophenone, 2-chlorobenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone, Michler's ketone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin Isopropyl ether, methyl benzoyl formate, p-isopropyl-
Carbonyl compounds such as α-hydroxyisobutylphenone, α-hydroxyisobutylphenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenyl ketone, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, thioxanthone, 2-chloro. Thioxanthone, 2-
Examples thereof include sulfur compounds such as methylthioxanthone, and peroxide compounds such as benzoyl peroxide and di-t-butyl peroxide. These photopolymerization initiators may be used alone or in combination of two or more. The amount of the photopolymerization initiator used is appropriately 0.01 to 10 parts by weight with respect to 100 parts by weight of the polymerizable monomer composition. When electron rays or gamma rays are used as the curing means, it is not always necessary to use a polymerization initiator.

The radiation-curable composition used in the present invention contains hydroquinone, hydroquinone monomethyl ether, 2, in order to prevent thermal polymerization during production and dark reaction during storage.
It is preferable to add a known thermal polymerization inhibitor such as 5-t-butylhydroquinone. The addition amount is preferably 0.005 to 0.05% by weight based on the total weight of the polymerizable compound.

The radiation curable composition used in the present invention includes
When non-glare property, whiteness, coloring property and the like are required, known inorganic and organic fine particles, dyes and pigments can be appropriately selected and added. In the case of fine particles, for example, silica, titanium oxide, calcium carbonate, magnesium oxide,
Barium sulfate, alumina, kaolin, talc, clay,
Examples thereof include inorganic fine particles such as mica, and organic fine particles such as crosslinked polystyrene, polyethylene, polypropylene and fluororesin.

The radiation curable composition used in the present invention includes
An organic solvent can be blended within the range not impairing the object of the present invention for the purpose of improving workability during coating and controlling the coating film thickness.

The organic solvent has a boiling point of about 50 ° C.
A temperature of 150 ° C. is preferable, but it is easy to use in terms of workability during coating and drying properties before and after curing. Specific examples include alcohol solvents such as methanol, ethanol and isopropyl alcohol, acetic ester solvents such as methyl acetate and ethyl acetate, ketone solvents such as acetone and methyl ethyl ketone, aromatic solvents such as toluene and dioxane. Cyclic ether solvent, etc. These solvents may be used alone or in combination of two or more.

The radiation curable composition used in the present invention includes
Various kinds of additives can be added as necessary within a range that does not impair the object of the present invention. For example, organic and / or inorganic particles for imparting antiglare properties (non-glare properties, matting properties) and slip properties, antioxidants, light stabilizers, stabilizers such as UV absorbers, surfactants, leveling agents , Antistatic agents, etc.

The laminated film of the present invention is produced by coating and curing the radiation curable layer (II) on the polyalkylene naphthalate film.

The radiation curing composition of the present invention may be applied by any of the usual coating methods such as brush coating, dip coating, roll coating, spray coating, flow coating, spin coating (spinner, whaler, etc.) and extrusion coating. The method is easily applicable. Each method has its own characteristics, and the coating method is appropriately selected depending on the required performance of the laminate or the intended use.

As a method for curing the radiation curable composition of the present invention, there may be mentioned a method of irradiating with active energy rays such as ultraviolet rays, electron rays or gamma rays. Practically, the method of irradiating with ultraviolet rays is simple and preferable.
Ultraviolet light sources include ultraviolet fluorescent lamps, low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, and carbon arc lamps.

The thickness of the radiation curable layer used in the present invention is 2
It must be at least μm. If it is thinner than this, sufficient surface hardness cannot be obtained, and interference fringes during coating tend to stand out on the surface of the coating film, which is not preferable.

[0040]

[Measurement of Physical Properties and Evaluation of Effects] The characteristic values of the present invention are based on the following measurement methods and evaluation criteria.

(1) Surface Roughness According to JIS-B0601-1976, a cutoff of 0.
25 mm, measuring length 4 mm, center line average roughness Ra (μm)
And the maximum roughness Rt (μm) were determined.

(2) Average sphere equivalent diameter of voids in a film formed of an incompatible polymer A cross section of the film cut in the machine direction or the vertical direction in the film forming process is 1000 to 5000 times with a scanning electron microscope. Take a magnified image of the image, apply at least 100 voids in the specified thickness range to the image analyzer,
The distribution of the diameter of the circle corresponding to the area of the void was obtained. The volume average diameter of this distribution was defined as the average equivalent spherical diameter of the void.

(3) Specific gravity 25 with a carbon tetrachloride-n-heptane density gradient tube
Values in ° C were used.

(4) Heat Shrinkage The film is 10 mm wide and 300 mm long in the longitudinal or width direction.
After cutting into 200 mm, marking at 200 mm intervals and fixing to a support plate under constant tension (5 g), the original length a (mm) of the marking interval is measured. Next, a load was applied using a clip of 3 g and the treatment was performed for 30 minutes while rotating in a hot air oven at 150 ° C., and the marking interval b (mm) was measured in the same manner as the measurement of the original length. The heat shrinkage rate was calculated by the following formula, and the average value of 5 was used.

Thermal shrinkage (%) = (ab) / a

(5) Optical Density The transmission density was measured using an optical densitometer (TR927, manufactured by Macbeth Co.). The thickness of the film and the optical density were plotted to determine the optical density corresponding to each thickness.

(6) Whiteness U manufactured by Shimadzu Corporation according to JIS-L-1015
When V-260 was used and the reflectances at wavelengths of 450 nm and 550 nm were B% and G%, respectively, the whiteness was expressed as 4B-3G.

(7) Stretchability When the film was formed continuously for 24 hours, no film breakage was evaluated as "good" and two or more times as "breakaged".

(8) Cushion rate (%) Dial gauge NO. 2109-10
The standard gauge head 900030 is used for the dial gauge stand NO. Using the 7001DGS-M, the thickness is calculated from the film thicknesses d ₅₀ and d ₅₀₀ of the respective films when a load of 50 g and 500 g is applied to the dial gauge pressing portion by the following formula.

Cushion rate = [(d ₅₀ −d ₅₀₀ ) / d ₅₀ ] × 100

(9) Shape Factor As in the case of obtaining the average equivalent spherical diameter of voids, the shape of the incompatible polymer on the film surface was applied to an image analyzer and the average ratio of major axis / minor axis of 100 pieces was expressed.

(10) Young's Modulus According to JIS-Z-1702, the tensile strength was measured at 25 ° C. and 65% RH using an “Instron” type tensile tester.

(11) Crystallization parameter ΔTcg Perkin-Elmer DSC-II (differential scanning calorimeter)
It measured using. The measurement conditions of DSC are as follows. That is, 10 mg of a sample is set in a DSC device,
After melting at a temperature of 300 ° C. for 5 minutes, it is rapidly cooled in liquid nitrogen. The temperature of this quenched sample is raised at 10 ° C./min, and the glass transition point Tg is detected. The temperature was further raised, and the crystallization exothermic peak from the glass state was taken as the cold crystallization temperature Tcc. The temperature was further raised and the heat of fusion was determined from the melting peak. Here, the difference between Tcc and Tg (Tcc-Tg) was defined as the crystallization parameter ΔTcg.

(12) Number of protrusions on the film surface 2 Detector type scanning electron microscope [ESM-3200,
Elionix Co., Ltd.] and cross-section measuring device [PMS-1,
Elionix Co., Ltd.], the height measurement value of the protrusion when scanning is performed with the height of the flat surface of the film as 0, and the measured value of the height of the projection is image processing apparatus [IBAS2000, Carl Zeiss Co., Ltd.].
Manufactured] to reconstruct the film surface protrusion image on the image processing device. Next, the highest value among the individual projections obtained by binarizing the projections in this surface projection image is taken as the height of the projection, and this is calculated for each projection. This measurement was repeated 500 times at different places, and those having a height of 20 nm or more were used as protrusions to determine the number of protrusions. The magnification of the scanning electron microscope is selected to be 1000 to 8000 times. In some cases, the number information such as a peak count obtained by a high-precision optical interference type three-dimensional surface analysis device (TOPO-3D manufactured by WYKO, objective lens: 40 to 200 times, use of a high resolution camera is effective) is given above. SE
You may read and use it as the value of M. Also, in order to capture the protrusions in three dimensions, tilt the film by 82.5 ° and set the magnification to 1
The number of protrusions is 1 m from the average value of 100 fields of view taken by taking a photograph with an electron microscope (SEM) at a magnification of 10,000 to 500,000 times.
You may convert it per m ² .

(13) Number of Particles Contained in Surface Layer In the present invention, the surface layer means a portion from the film surface to a depth of 3D. Here, 3D means the average particle diameter D × 3 of the particles contained in the film. The cross section of the film is observed by a transmission electron microscope (TEM), and 3D is observed from the surface.
The number of particles present in the part up to 3000 to 100
Observation was carried out at a magnification of 000 for 500 fields of view, and the average number of particles converted per 1 mm ² was obtained.

(14) Average Particle Size of Particles in Film The polymer is removed from the film by a plasma low temperature ashing method to expose the particles. As for the processing condition, the polymer is incinerated, but Grain selects the condition that it is not damaged as much as possible. The particles are observed with a scanning electron microscope (SEM), and the particle image is processed with an image analyzer. The magnification of the SEM is approximately 2000 to 10,000 times, and the visual field in one measurement is appropriately selected from approximately 10 to 50 μm on each side. The volume average diameter f is obtained by the following equation from the particle diameter and its volume fraction when the number of particles is 500 or more by changing the observation location.

F = Σf _i · Nv _i where f _i is the particle size and Nv _i is the volume fraction. When the particles are organic particles or the like and are significantly damaged by the plasma low temperature ashing method, the following method may be used.

A cross section of the film was taken by a transmission electron microscope (TE
M) is used and observation is performed at a magnification of 3000 to 100000 times.
The TEM section thickness is about 1000 angstroms,
The observation was performed for 500 fields or more in different places, and the volume average diameter f was obtained from the above formula.

(15) Average diameter of spherulites The cross section of the film is observed with an optical or electron microscope, and the measurement is repeated until a total of 100 spherulites can be observed, and the obtained values are averaged to obtain spherulites. The average diameter was used.

(16) Degree of molecular orientation The infrared polarization ATR method is used. As the device, an FT-IR (IFS-113V) manufactured by Bruker, to which an auxiliary device for polarization ATR measurement (manufactured by Bio-Rad Digilab) is attached is used. This ATR device has a square Inte with a symmetrical edge and a thickness of 3 mm and a side of 25 mm.
The rnal Reflection Element was attached, and the absorption measurement was performed in two directions parallel and perpendicular to the stretching direction.

The incident direction of light is taken in the length direction of the film,
The spectrum of the coated surface and that of the uncoated surface are measured using polarized light perpendicular to the entrance slope, and are designated as S _MC and S _MP , respectively. In addition, the incident direction of light is set to the film width direction, and the spectrum of the coated surface and the uncoated surface is measured using polarized light perpendicular to the incident surface, and they are S _TC and S _TP , respectively. However, when there is no non-coated surface, the coated surface is wiped off with various solvents, water, etc., and then the substrate surface is immediately suitable.

The difference spectrum between the coated surface and the uncoated surface is obtained by the following procedure. As the internal reference band when calculating the difference spectrum, the absorption band of the base film observed in the wave number region close to the absorption band of the coat layer required for analysis is selected.

A coefficient is determined so that the absorbance of the internal reference absorption band becomes 0, and a difference spectrum obtained by subtracting the spectrum of the uncoated surface from the spectrum of the coated surface is obtained for each polarization component.

[Equation 1] And

Points at two predetermined wave numbers on the difference spectrum thus obtained are connected to form a baseline,
The height from the baseline to the peak of the absorption band is the coating layer absorption band

[Equation 2] And

The degree of orientation (P) is calculated from the absorbance of the coating layer thus obtained by the following equation.

[0066]

(Equation 3) (17) Identification of Hydrophilic Group-Containing Polyester by ESCA Method Measurement by ESCA method (X-ray photoelectron spectroscopy) was performed under the following conditions.

Equipment: Shimadzu ESCA750 Excited X-ray: Mg, Kα1.2 ray (1253.6 eV) Energy correction: The binding energy value of the C1S main peak was adjusted to 284.6 eV.

Photoelectron escape angle (θ): 90 ° Identification was carried out at a depth within 100 A from the surface of the crosslinked modified layer by the above method, and the atomic number ratio was determined from the S _2P / C _1S peak area ratio attributed to hydrophilic groups. Was determined and the case where the value was 0.001 or less was set as the detection limit or less.

From the chemical state of the detected element, C _1S and O
The presence or absence of polyester was identified by the proportion of _1S peak components and the peak shape, especially the presence or absence of π-π ^* satellite due to the presence of benzene ring due to polyester.
As a result, the S _2P / C _1S atomic number ratio and the case where polyester was not detected were marked with “◯”, and the case where both or either were detected was marked with “X”.

(18) Abrasion resistance The base film or the surface-hardened layer was rubbed with steel wool # 0000 and the degree of scratches was evaluated according to the following criteria.

S3: Hardly rubbing hardly scratches S2: Slight rubbing slightly scratches S1: Slight rubbing scratches

(19) Pencil hardness According to JIS K5400, scratches were generated when pencils of various hardness were applied to the surface of the substrate film or the surface-hardened layer at an angle of 90 ° under a load of 1 kg. It is indicated by the hardness of the pencil at that time.

(20) Adhesiveness Cross-cut (1 mm ² square 100
Cellophane adhesive tape (“Cellotape” CT-24 manufactured by Nichiban Co., Ltd.) is attached onto the tape, and the degree of peeling after peeling the “Cellotape” by hand is observed and the following criteria are used. evaluated.

A3: Good (peeling area less than 5%) A2: Slightly inferior (peeling area 5% or more and less than 20%) A1: Poor (peeling area 20% or more)

(21) Curl property A test piece of 15 cm square was cut out from the laminated film, and 20
At 60 ° C. and 60% RH, the surface of the surface-hardened layer was allowed to stand still on a horizontal plate, and the floating distance from the plate at the four corners was measured, and the maximum value (mm) was taken as the curl value.

K3: Good (less than 5 mm) K2: Slightly inferior (5 mm or more, less than 15 mm) K1: Poor (15 mm or more)

(22) A strip-shaped test piece with a width of 1 cm and a length of 5 cm was cut out from the flexible laminated film and wound on a stainless steel rod with the hardened layer on the outside, and the minimum diameter without cracks was examined. .

(23) Water resistance against boiling After immersing the laminated film in boiling water for 1 hour, the presence or absence of abnormal appearance such as cracks was observed, and the same adhesion test as in (28) was conducted.

(24) Humidity and heat resistance Using a constant temperature and constant humidity tank (Platinum Sumider PH-1G type manufactured by Tabai Espec Co., Ltd.), 60 ° C., 90% RH
After performing a heat and humidity test under the following conditions, the appearance changes such as cracks are observed, and further, the wear resistance of (18), (1
A pencil hardness of 8) and an adhesion test of (20) were conducted.

(25) Moisture absorption curl property A curl property test similar to that of (24) was conducted by spraying a fixed amount of water on the cured film surface of the laminated film measured by (24).

(26) Haze Integrating sphere type light transmitting device (Japan Precision Optical Co., Ltd. HTR
Meter SEP-H-2), JIS K-671
It measured according to 4.

(27) Surface Glossiness The glossiness was measured according to JIS Z-8741 using a glossiness measuring device (Suga Test Instruments Co., Ltd. digital variable angle gloss meter UGV-4-D).

[0083]

【Example】

Example 1 <Preparation of polyethylene 2,6-naphthalate layer (I)>
Polyethylene 2,6-naphthalate homopolymer chip manufactured by a conventional method (intrinsic viscosity [η] = 0.7)
After being sufficiently dried in vacuum, it is supplied to an extruder, melt-extruded at 295 ° C., filtered through a 10 μm-cut metal sintered filter, and then extruded into a sheet from a T-shaped die, and cooled at a surface temperature of 50 ° C. It was wound on a drum and cooled and solidified. In order to improve the adhesion between the sheet and the surface of the cooling drum during this period, a wire electrode was arranged on the sheet side and a DC voltage of 6000 V was applied. The unstretched polyethylene 2,6-naphthalate film thus obtained was stretched 3.5 times in the longitudinal direction by a roll group heated to 120 ° C. to obtain a uniaxially stretched film. Next, one side of this film was subjected to corona discharge treatment in a carbon dioxide atmosphere to obtain a polyethylene 2,6-naphthalate layer (I).

<Formation of Crosslinked Modified Layer> A crosslinked modified layer having the following composition was synthesized by a conventional method. Dimethyl terephthalate 100
Parts by weight, dimethyl isophthalate 75 parts by weight, 5-sodium sulfoisophthalate dimethyl 10 parts by weight, ethylene glycol 95 parts, neopentyl glycol 85 parts by weight, manganese acetate tetrahydrate 0.106 parts by weight, calcium acetate dihydrate 0 0.07 part by weight and mixed under a nitrogen stream for 14
Methanol was allowed to flow out at 0 to 220 ° C., an ester exchange reaction was performed, and then 0.09 parts by weight of trimethyl phosphate was added,
Add 0.06 parts by weight of antimony trioxide and increase from 240 ° C to 2
The temperature was raised to 80 ° C over 30 minutes and the pressure was gradually decreased from atmospheric pressure to 0.5 mmHg to remove the excess diol component out of the form, and this state was kept for 40 minutes to carry out the polycondensation reaction. A hydrophilic group-containing polyester copolymer having a glass transition temperature of 62 ° C. and an intrinsic viscosity [η] = 0.6 was obtained. Next, a mixture of 250 parts by weight of this copolymer and 110 parts by weight of butyl cellosolve was stirred at 150 ° C. for 4 hours to obtain a uniform solution. 48 ml of water was added to the obtained solution under high speed stirring.
0 parts by weight was gradually added dropwise to obtain a uniform, milky white opaque dispersion having a solid content concentration of 25% by weight. To 70 parts by weight of the thus obtained dispersion, 100 parts by weight of water was added, and further 30 parts by weight of water, 1.5 parts by weight of benzoyl peroxide, 12 parts by weight of methyl methacrylate, 2.5 parts of polyoxyethylene alkyl ether phosphate ester. A dispersion containing a part by weight of a polymerization initiator was added, and the mixture was stirred under a nitrogen gas flow for 1 hour and then heated to 75 ° C. Next, a mixture of 40 parts by weight of methyl methacrylate, 30 parts by weight of ethyl acrylate, and 15 parts by weight of glycidyl methacrylate as an acrylic compound to be grafted was dropped into the above-mentioned preparation liquid kept at 85 ° C. under stirring for 60 minutes. 120 at 85 ° C under nitrogen flow
Stirring was continued for a minute to obtain an aqueous dispersion graft copolymer having a solid content concentration of 27% by weight. The grafting ratio of the graft copolymer was 44%.

An aqueous dispersion of the graft copolymer produced above and a melamine-based cross-linking agent "Nikalac" as a cross-linking agent
MW12LF (manufactured by Sanwa Chemical Co., Ltd.) was mixed with 5 parts by weight of a cross-linking agent to 100 parts by weight of the graft polymer in a solid content weight ratio, and further diluted with water to a solid content concentration of 5.0% by weight. , An average particle size of 0.10 μm as a lubricant in the coating agent
Of coroyl silica to 100 parts by weight of the resin solid content.
5 parts by weight was added. Then, this coating agent was applied to the discharge-treated surface of the polyethylene 2,6-naphthalate film layer using a rod coater so that the thickness after biaxial stretching would be 0.08 μm, and a laminated film having a thickness of 100 μm. Got The crosslinked modified layer was molecularly oriented, and the presence of the hydrophilic group-containing polyester at a depth of 100 angstroms from the surface layer of the crosslinked modified layer was below the detection limit in the ESCA method.

60 parts by weight of dipentaerythritol hexaacrylate and 30 parts by weight of polyester acrylate (“Aronix” M-7100 manufactured by Toagosei Co., Ltd.) were formed on the crosslinked modified layer (undercoat layer) of the PEN film thus obtained. , 10 parts by weight of hydroxypropyl acrylate, 1
-Hydroxycyclohexyl phenyl ketone 1 part by weight,
The curable layer composition obtained by stirring and mixing 7 parts by weight of 2- (2-hydroxy-5-methylphenyl) benzotriazole had a thickness after curing of 10 μm using a bar coater.
Was applied. This was passed under a N ₂ atmosphere at a speed of 20 m / min under 4 high pressure mercury lamps having a strength of 120 mW / cm set at a height of 10 cm from the coating surface. The coating film was completely cured.

The surface of the obtained laminate was smooth and free from fogging, and the abrasion resistance, pencil hardness and adhesion were S-4,
4 and A3, flexibility was 8 mm, and both curl and moisture absorption curl were K3.

When the boiling water resistance of this laminate was examined, cracking was not observed at all, and there was no deterioration in the adhesiveness of the cured layer, which was A3.

After conducting a moist heat resistance test for 10 days, the characteristics were examined, and no abnormalities in appearance were observed, and neither abrasion resistance nor adhesiveness of the cured film was deteriorated, which was excellent. It was

Example 2 A laminated film was obtained in the same manner as in Example 1 except that the thickness of the curable layer was 3 μm. The laminated film thus obtained was the same as Example 1 except that the pencil hardness was 3H and the flexibility was 6 mm.

Comparative Example 1 A polyethylene terephthalate homopolymer chip (intrinsic viscosity = 0.6) produced by a conventional method was sufficiently vacuum dried, then fed to an extruder and melt-extruded at 280 ° C.
After filtering with a 10 μm cut metal sintered filter, T
Extruded into a sheet from the letter-shaped die, and the surface temperature is 50 ℃.
Was solidified on the cooling drum of No. 3 by the electrostatic charge method. Then, the cast sheet was stretched 3.5 times using a roll group heated in the longitudinal direction at 95 ° C. according to a conventional method to obtain a uniaxially stretched film, and then corona discharge was applied to one side in the same manner as in Example 1. After the treatment, a crosslinked modified layer coating material was applied, and then stretched in the width direction. On the crosslinked modified layer of the obtained biaxially stretched polyethylene terephthalate film, a hardening layer (thickness: 10 μm) was formed in the same manner as in Example 1. ) Was provided to obtain a laminated film of Comparative Example 1. Abrasion resistance is S-4, pencil hardness is 3H, and adhesion is A3
However, the flexibility is 10 mmφ or more, the curl / moisture absorption curl is K-1, and the boiling water resistance is small cracks.
A decrease in adhesiveness of the cured layer was observed and was A1. The laminated film of the present invention having a PEN film as a support film is excellent in many properties as compared with a laminated film having a polyethylene terephthalate film as a support film,
There was nothing inferior.

Example 3 Polyethylene 2,6-naphthalate (Intrinsic viscosity [η] =
0.7) was supplied to the extruder A, melted at 295 ° C. by a conventional method, and introduced into the center of the T-die three-layer die.

On the other hand, 85% by weight of the above-mentioned polyethylene 2,6-naphthalate had an average particle size of 0. A raw material added with 15% by weight of 3 μm colloidal silica was supplied to an extruder B, melted at 295 ° C. by a conventional method, laminated on both surface layers of a T-die three-layer die, and the melt sheet was heated to a surface temperature of 25 ° C. The solid was cooled and solidified on the maintained cooling drum by the electrostatic charge method. Then, the cast sheet was stretched 3.5 times in the longitudinal direction by using a roll group heated to 120 ° C. according to a conventional method, and then stretched at 25 ° C.
After cooling to 1, the crosslinked modified layer coating material of Example 1 was applied, and then the stretched film was introduced into a tenter, stretched in the width direction in an atmosphere heated to 125 ° C, and heat-set at 225 ° C. A film having a thickness of 100 μm was obtained. The thickness of each film layer was 0.5 μm on the surface layer and 99 μm on the central layer. The curable layer of Example 1 was formed on the crosslinked modified layer of the PEN film containing the thus-obtained inert particles to form uniform unevenness on the surface, to obtain a laminated film. The surface of the obtained laminated film is smooth and free from fogging,
Abrasion resistance, pencil hardness, and adhesiveness are S-4, 3H, and
A3, flexibility was 6 mmφ, and curl and moisture absorption curl were both K3.

When the boiling water resistance of this laminate was examined, no cracks were found, and there was no deterioration in the adhesiveness of the cured layer, which was A3.

After conducting a moist heat resistance test for 10 days, the characteristics were examined. No abnormal appearance was observed, and neither abrasion resistance nor adhesion of the cured film was excellent and it was excellent. . Further, since the back surface has uniform unevenness, it has excellent slipperiness and is particularly excellent in processability and handleability in post-processing such as slitting, cutting, laminating and coating.

Example 4 PEN used in Example 1 was used as a central layer and ΔTcg was 30.
Polyester film having PEN at both temperatures of 180 ° C. for both outermost layers was dried under reduced pressure at 180 ° C. for 3 hours (400 Pa).
And feed each to two extruders and melt at 295 ° C.
These polymers are combined and laminated in a rectangular confluent block (feed block) for three layers, and by an electrostatically applied casting method, they are wound around a casting drum with a refrigerant temperature of 30 ° C., cooled and solidified, and an unstretched three-layer structure is formed. I got a film. At this time, the discharge amount of each extruder was adjusted to adjust the thickness of the outermost layer. The surface of the unstretched film which was not in contact with the drum was heat-treated at 190 ° C. for 5 seconds using a known radiation heater. After the heat treatment, the film was stretched at a temperature of 90 ° C. in the longitudinal direction by a factor of 3.4, the cross-linking modification layer coating agent was applied in the same manner as in Example 1, and then a stenter was used to stretch at a stretching rate of 2000% / min to 100.
Draw 3.5 times in the width direction at ℃, 210
Heat treatment was performed at 5 ° C. for 5 seconds to obtain a biaxially oriented PEN film having a total thickness of 100 μm (the outermost layers were 0.2 μm each).
The number of surface protrusions of this film is 200,000 / mm ² , and N _R is 4
It was 5. A curable layer was formed in the same manner as in Example 1 using this film as a support film to obtain a laminated film. The abrasion resistance, pencil hardness, and adhesiveness of the obtained laminated film are S-4, 3H, and A3, respectively, and the flexibility is 6 mmφ,
The curl and moisture absorption curl were both K3.

When the boiling water resistance of this laminate was examined, cracks were not observed at all, and there was no deterioration in the adhesiveness of the cured layer, which was A3.

After conducting a moist heat resistance test for 10 days, the characteristics were examined and no abnormalities in appearance were observed, and neither abrasion resistance nor adhesiveness of the cured film was deteriorated and it was excellent. . Further, since the back surface has uniform unevenness, it has excellent slipperiness and is particularly excellent in processability and handleability in post-processing such as slitting, cutting, laminating and coating.

Example 5 The thickness of the curable layer was the same as in Example 1 except that a dispersion liquid containing 2 parts by weight of silica particles having an average particle diameter of 1.8 μm was used as the curable layer composition. To obtain a laminated film having a thickness of 3 μm. The haze of this laminated film is 3.5.
%, The glossiness was 100, and the antiglare property was excellent.

Example 6 The thickness of the curable layer was the same as in Example 1 except that a dispersion containing 4 parts by weight of silica particles having an average particle diameter of 3.0 μm was used as the curable layer composition. To obtain a laminated film having a thickness of 3 μm. The haze of this laminated film is 30%,
The glossiness was 36, which was excellent in non-glare property.

[0101]

Since the present invention is constructed as described above,
Excellent in surface hardness, abrasion resistance, scratch resistance, flexibility, surface uniformity, small heat shrinkage rate, excellent fast curing property, and transparent to white, hiding, and coloring. It is also excellent in slipperiness, processability and handleability,
Thus, a laminated film having very little curl was obtained.

The laminated film of the present invention is excellent in surface hardness, abrasion resistance, scratch resistance and flexibility, and has a small surface uniformity, a small heat shrinkage rate and an extremely small curl, so that it can be applied to a wide range of applications. it can. For example, touch panels, decorations and displays attached to metal plates and glass, scattering prevention attached to window glass, displays such as electronic white boards and whiteboards, paper substitutes, that is, cards, labels, stickers, courier slips, It can also be used as an image receiving paper for video printers, an image receiving paper for bar code printers, maps and the like, as well as various surface protective materials such as calculators, covers for CRTs and measuring instruments. Also, home appliances for coated metal plates,
It can also be used for office equipment, building materials, vehicles, steel furniture, etc. In particular, it can be used as an exterior member for home electric appliances and the like because it has excellent designability and sharpness. In addition, since the polyalkylene naphthalate film has a higher Young's modulus and a higher rigidity than the polyethylene terephthalate film, curling can be suppressed even if the curable layer is made thicker to increase the hardness, and the active energy ray of higher strength is used. It is also excellent in high-speed processability using.

Claims (8)

[Claims] 1. A laminated film obtained by laminating a radiation curable layer (II) on a base film (I), wherein the base film (I) is a polyalkylene naphthalate film. Laminated film. 2. The crosslinked modified layer (III) which is molecularly oriented is laminated between the base film (I) and the radiation curable layer (II). Laminated film. 3. A polyalkylene naphthalate film is a polyethylene 2,6-naphthalate film, a polyethylene 2,6-naphthalate / polyethylene terephthalate composite film or a polyethylene 2,6-naphthalate / polyethylene terephthalate / polyethylene 2,6-naphthalate composite film. It is a film, The laminated film of Claim 1 characterized by the above-mentioned. 4. The radiation-curable layer (II) has a thickness of 2 μm or more and a pencil scratching value in JIS-K5400 (paint general test method) -a pencil hardness of 2H or more by a tester method. Item 2. The laminated film according to item 1. 5. The radiation-curable layer (II) comprises at least one monomer (A) having three or more (meth) acryloyloxy groups in one molecule and one or two monomers in one molecule. A layer of a radiation-cured reaction product comprising a radiation-curable monomer mixture comprising at least one kind of the monomer (B) having an ethylenically unsaturated double bond.
The laminated film according to. 6. A base film (I) is a film layer (IV) containing at least one surface of a thermoplastic resin (a) and inert particles as main components, and the base film (I) is contained in the film layer (IV). The average particle diameter of the inert particles is 0.1 to 10 times the thickness of the film layer (IV), and the content of the inert particles is 0.1 to 5
0% by weight and the thickness of the film layer (IV) is 0.00
It is 5-3 micrometers, The laminated film of Claim 1 characterized by the above-mentioned. 7. The substrate film (I) is characterized in that at least one side thereof is a polyester layer (V) having essentially no particles and having projections formed by utilizing crystallization of polyester itself. The laminated film according to claim 1. 8. The base film (I) is a polyester film having a heat shrinkage at 150 ° C. of 0.5% or less and a specific gravity of 1.3 or less. Laminated film.