JP2001205739A - Metal vapor deposition composite sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal vapor deposition composite sheet high in the peel strength of a film and a nonwoven fabric and excellent in the glossiness of a metal vapor deposition surface. SOLUTION: The metal vapor deposition composite sheet is constituted by bonding the thermoplastic film and the nonwoven fabric through an adhesive and a metal layer is formed on the surface on the side opposite to the bonding surface with the nonwoven fabric of the film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite sheet having a large peel strength between a film and a non-woven fabric and having excellent glossiness on a metal-deposited surface.

[0002]

2. Description of the Related Art Conventionally, thermoplastic films coated with metal such as aluminum have been used for electric materials such as capacitors, packaging materials for food packaging and clothing, and decorative materials such as gold and silver thread, labels and stickers. Or, it is widely used for agricultural materials and industrial materials. As these metal deposited films, films having various thicknesses are used depending on the application, but have the following disadvantages. (1) Easy to tear and tear. (2) The waist is weak and easily wrinkled. Increasing the thickness of the film to make it stiff may result in reduced flexibility or weight. (3) No cushioning.

[0003]

As an improvement over these disadvantages, there is known a composite sheet in which a nonwoven fabric or the like is bonded to the non-deposited surface side of a metal-deposited film with an adhesive.

[0004] However, the composite sheet bonded using an adhesive has the following disadvantages. (4) The adhesive is deteriorated or deteriorated by the influence of the temperature, humidity, light or the like of the use environment, so that the deposited film and the nonwoven fabric are easily peeled off, and the durability is poor. (5) When the vapor-deposited film and the nonwoven fabric are bonded to each other, the vapor-deposited surface is stained or damaged. (6) In order to solve the above-mentioned problem (5), after bonding the thermoplastic film and the non-woven fabric with an adhesive and then performing metal deposition, a decomposition product such as an adhesive component or a solvent component contained in the adhesive is obtained. Are generated, and a uniform metal layer is not formed.

[0005] In recent years, in packaging and medical applications, a composite sheet that does not use an adhesive has been demanded in order to eliminate the adverse effects of the adhesive. As a method without using an adhesive, a composite sheet in which the surface of a nonwoven fabric is directly coated with a thermoplastic resin has been provided.
There is a fatal drawback that uniform mirror gloss cannot be obtained even when metal deposition is performed because the smoothness of the coated resin surface is poor. As another method that does not use an adhesive, a composite sheet in which a film and a nonwoven fabric are integrated by embossing is known, but the sheet has a disadvantage that a metal layer is damaged during embossing, However, even if metal deposition is performed after embossing, there is a defect that surface gloss is inferior due to surface irregularities.

The present invention has been made in view of the background of the prior art.
An object of the present invention is to provide a composite sheet having a large peel strength between a film and a non-woven fabric and excellent in glossiness of a metal-deposited surface.

[0007]

The present invention employs the following means in order to solve the above-mentioned problems. That is, in the composite sheet of the present invention, the thermoplastic film and the nonwoven fabric are bonded without interposing an adhesive, and the metal layer is formed on the surface of the film opposite to the bonding surface with the nonwoven fabric. It is characterized by the following.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is based on the above-mentioned object, that is, a study on a composite sheet having a large peel strength between a film and a non-woven fabric and an excellent glossiness of a metal-deposited surface. When they were bonded without using an agent and then subjected to metal deposition, they found that such a problem could be solved at once.

In the metal-deposited composite sheet of the present invention, it is important that the thermoplastic film and the nonwoven fabric are adhered without using an adhesive.

For example, it is not preferable to bond such a thermoplastic film and a nonwoven fabric with an adhesive because the adhesive is deteriorated by the influence of humidity and temperature, and the film and the nonwoven fabric are easily peeled off. In addition, when a thermoplastic film and a nonwoven fabric are bonded with an adhesive, when a metal surface is applied to the film surface, a fatal defect that a deposition surface becomes non-uniform due to a decomposition product of an adhesive component or a solvent component occurs. .

As the thermoplastic resin used in the thermoplastic film of the present invention, polyester, polyamide, polyethylene, polypropylene, their respective copolymers, and blends thereof can be used. And their copolymers or blends are preferably used.

As such a polyester, a polyester containing an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid or an alicyclic dicarboxylic acid and a diol as main components is preferable.

The aromatic dicarboxylic acid component includes, for example, terephthalic acid, isophthalic acid, phthalic acid,
1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,
4'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'-diphenylsulfonedicarboxylic acid and the like can be used, and among them, terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid and the like are preferable. It is better to use As the aliphatic dicarboxylic acid component, for example, adipic acid, suberic acid, sebacic acid, dodecanedioic acid and the like can be used, and among them, adipic acid and the like are preferably used. Further, as the alicyclic dicarboxylic acid component, for example, 1,4-cyclohexanedicarboxylic acid and the like can be used. One of these acid components may be used alone, or two or more thereof may be used in combination. Further, an oxyacid such as hydroxybenzoic acid may be partially copolymerized.

As the diol component, for example, ethylene glycol, 1,2-propanediol, 1.3
-Propanediol, neopentyl glycol, 1,3
-Butanediol, 1,4-butanediol, 1,5-
Pentanediol, 1,6-hexanediol, 1,2
-Cyclohexanedimethanol, 1.3-cyclohexanedimethanol, 1.4-cyclohexanedimethanol, diethylene glycol, triethylene glycol,
Polyalkylene glycol, 2,2'bis (4'-β-
(Hydroxyethoxyphenyl) propane and the like can be used. Among them, ethylene glycol is preferably used. These diol components may be used alone or in combination of two or more.

As the polyester used for the thermoplastic film of the present invention, polyethylene terephthalate, a copolymer of ethylene terephthalate and ethylene isophthalate, a copolymer of ethylene terephthalate and ethylene naphthalate, hexamethylene terephthalate and cyclohexane dimethylene terephthalate And a blend of polyethylene terephthalate and polybutylene terephthalate, etc. can be preferably used.

It is important for the thermoplastic film of the present invention that a metal thin film layer is formed on the surface of the film opposite to the adhesive surface of the nonwoven fabric. As the metal to be formed, gold, silver, copper, aluminum, palladium, nickel, cobalt, zinc, tin, titanium, indium, or the like alone or in combination, or an oxide thereof is used. Particularly preferably, aluminum, nickel, zinc,
Single or mixed tin and oxides thereof are used. By forming a metal thin film layer, conductivity,
Light shielding properties, decorative properties, gas barrier properties, and the like can be imparted. The thickness of the formed metal layer is not particularly limited, but is preferably at least 100 Å to 1000 Å.

The thermoplastic film of the present invention may contain, if necessary, an organic lubricant such as a flame retardant, a heat stabilizer, an antioxidant, an ultraviolet absorber, an antistatic agent, a pigment, a dye, a fatty acid ester, or a wax. An antifoaming agent such as siloxane can be blended.

The thickness of the thermoplastic resin film of the present invention is as follows:
Although it can be freely selected according to the application, it is preferably 1 to 100 μm, more preferably 1 to 50 μm, and particularly preferably 1 to 10 μm.

The non-woven fabric in the present invention is a non-woven fabric composed of fibers such as polyolefin, polyamide and polyester, preferably a non-woven fabric composed of polyester fibers mainly composed of polyethylene terephthalate and polyethylene naphthalate, particularly preferably polyethylene terephthalate. It is a non-woven fabric composed mainly of polyester fibers.

The nonwoven fabric according to the present invention may be used according to the purpose.
The basis weight and fiber diameter can be arbitrarily selected and used, but the basis weight is preferably from ² to 200 g / m ² and the fiber diameter is preferably from 1 to 30 μm.

The nonwoven fabric of the present invention may be subjected to a chemical treatment such as an acid or alkali treatment, a corona treatment, a low-temperature plasma treatment, or the like, as necessary.

The metal-deposited composite sheet of the present invention is obtained by bonding a thermoplastic film and a nonwoven fabric without using an adhesive. The method for forming such a composite sheet may be any method. For example, the composite sheet is preferably formed by thermally bonding an unstretched thermoplastic film and a nonwoven fabric made of unstretched fibers and co-stretching. Can be.

Such an unstretched thermoplastic film can be produced, for example, by extruding a polymer onto a cooling drum using, for example, the above polyester by a T-die extrusion method. In this case, an unstretched film having an arbitrary thickness can be obtained by adjusting the discharge amount of the polymer, the size of the die slit, and the rotation speed of the cooling drum.

The non-woven fabric made of unstretched fibers can be formed by adjusting the temperature, the amount of hot air, or the speed of hot air blown from the periphery of the die when the molten polymer is discharged from the die, for example, by a melt blow method. A fiber that is nearly amorphous in orientation can be obtained.

The unstretched film and the unstretched nonwoven fabric obtained by the above-described method can be thermally bonded by, for example, overlapping and feeding between heated rolls and applying pressure. The heat bonding temperature is preferably performed at a temperature in the range from the glass transition temperature (Tg) of the unstretched film or unstretched nonwoven fabric to a temperature around Tg + 30 ° C.

Next, the unstretched film and the unstretched nonwoven fabric that have been thermally bonded are preferably co-stretched at least uniaxially, and more preferably biaxially co-stretched. By co-stretching the film and the nonwoven fabric integrally, the orientation of the film and the nonwoven fabric is promoted, respectively, and a high-strength composite sheet can be formed. As the biaxial stretching method here, any of a sequential biaxial stretching method and a simultaneous biaxial stretching method may be used. The stretching ratio is not particularly limited, but is preferably about 2 to 8 times.

Further, the composite sheet after co-stretching is preferably subjected to a heat treatment, for example, at a temperature lower than the melting point of the thermoplastic film and the nonwoven fabric for 0.5 to 60 seconds.

The method for forming a metal thin film layer on the surface of the thermoplastic film of the present invention is not particularly limited, but the thermoplastic film and the nonwoven fabric are adhered by the above-mentioned method and then a continuous or batch vacuum evaporator. , Electric heating, sputtering, ion plating, ion beam or the like. Before vapor deposition, the surface of the film may be subjected to a corona discharge treatment or the like in air or other various atmospheres, if necessary.

The metal-deposited composite sheet of the present invention can be used as a base material for a metal-deposited pressure-sensitive adhesive tape by applying an adhesive or the like to the metal layer side or the nonwoven fabric side or both depending on the intended use. Further, when an adhesive is applied, a configuration in which an application surface and a release sheet material such as paper are combined may be employed.

The method of applying the pressure-sensitive adhesive is not particularly limited, but it can be applied using a roll coater, a gravure coater, a reverse coater, a bar coater or the like. <Method for Measuring Characteristics> (1) Gloss Deposition Surface Glossiness measured at an angle of 60 ° in accordance with JIS K7105 using a metal deposition surface as a measurement surface, and determined as follows.

A sample having a glossiness of less than 700% was evaluated as x; a sample having a glossiness of 700% or more and less than 800% was evaluated as △. Δ means more than practical. (2) Peeling Resistance After immersing the prepared composite sheet in warm water at 50 ° C. for 24 hours, in accordance with the T-shaped peeling test of JIS K 6854,
The peel strength between the film and the non-woven fabric was measured and determined as follows.

A sample having a peel strength of less than 0.1 N / 25 mm was evaluated as x. A sample having a peel strength of 0.1 N / 25 mm or more and less than 0.2 N / mm was evaluated as ○. .
Δ means more than practical. (3) Film Thickness The film thickness was measured using a light interference type thickness meter (HIT-25 manufactured by Toray Techno Co., Ltd.). (4) Weight per unit area of non-woven fabric It was determined by subtracting the weight of the film from the weight of the composite sheet.
The weight of the film was calculated from the thickness and density of the film. (5) Fiber diameter of non-woven fabric The fiber diameter of the non-woven fabric was obtained by taking a 1000-fold photograph with an electron microscope, measuring the diameter of 100 arbitrary fibers, and calculating the average value.

[0033]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

Example 1 Polyethylene terephthalate raw material ([η] = 0.49,
Tm = 253 ° C) by melt blow method, and has a basis weight of 2
An unstretched nonwoven fabric of 30 g / m ² was produced.

Next, a polyethylene terephthalate raw material ([η] = 0.65, Tm = 257 ° C.) was extruded with a T-die die and cast on a cast drum having a surface temperature of 25 ° C. to produce an unstretched film.

The unstretched film and the unstretched nonwoven fabric are superimposed, supplied to a roll-type stretching machine, and thermally bonded between preheated rolls at 85 ° C., and then a nip roll linear pressure of 5 N / cm and a peripheral speed of 95 ° C. After co-stretching 3.3 times in the longitudinal direction between the rolls having differences, once cooled to room temperature, it was fed into a tenter type horizontal stretching machine, and co-stretched 3.5 times in the width direction at a temperature of 95 ° C. Further, heat treatment was performed in a heat treatment zone at 200 ° C. for 5 seconds to obtain a composite sheet having a film thickness of 2 μm, a nonwoven fabric fiber diameter of 5.1 μm, and a basis weight of 20 g / m ² .

An aluminum metal was coated on the film surface of the composite sheet by using an electron beam heating vacuum evaporation machine.
Evaporated to a thickness of 00 to 500 angstroms.

The vapor deposition surface glossiness of the sheet material was ○ at 830%, and the peeling resistance was で at 0.3 N / 25 mm.

Comparative Example 1 A polyester film having a thickness of 2 μm and a fiber diameter of 5.1 μm were prepared in the same manner as in Example 1 except that the film and the nonwoven fabric were separately stretched.
A polyester stretched nonwoven fabric having a basis weight of 20 g / m ² was produced.

Then, only the polyester film having a thickness of 2 μm was vapor-deposited with aluminum metal to a thickness of 400 to 500 angstroms using an electron beam heating type vacuum vapor deposition machine.

Next, 5 g / m ^{2 of a} vinyl acetate-based adhesive was applied to the non-deposited surface of the film, and bonded to a stretched polyester nonwoven fabric to produce a composite sheet. The vapor-deposited surface glossiness of the composite sheet was 620% ×, and the peel resistance was 0.07 N / 25 mm ×.

Comparative Example 2 A polyester film having a thickness of 2 μm and a fiber diameter of 5.1 μm were prepared in the same manner as in Example 1 except that the film and the nonwoven fabric were separately stretched.
A polyester stretched nonwoven fabric having a basis weight of 20 g / m ² was produced.

Next, 5 g / m ^{2 of a} vinyl acetate-based adhesive was applied to a ² μm-thick polyester film and bonded to a stretched polyester nonwoven fabric to form a composite sheet and wound up.

Thereafter, the surface of the polyester film of the composite sheet was coated on the surface of the polyester film by using an electron beam heating vacuum evaporation machine.
Aluminum metal was deposited to a thickness of 400-500 Å. The composite sheet has a deposition surface gloss of 710.
%, The peel resistance was 0.08 N / 25 mm ×.

[0045]

[Table 1]

As is clear from Table 1, the film of Example 1 has excellent peeling resistance and good glossiness on the vapor-deposited surface because the thermoplastic film and the nonwoven fabric are bonded without using an adhesive. On the other hand, those of Comparative Examples 1 and 2 are inferior in peel resistance and glossiness of the vapor deposition surface.

[0047]

According to the present invention, a composite sheet having the following effects can be provided. (1) The film and the nonwoven fabric do not peel off even when the humidity or temperature environment changes. (2) No decomposition product such as an adhesive is generated. (3) Since the thermoplastic film is reinforced with nonwoven fabric,
Hard to tear, hard to tear. (4) Excellent cushioning and flexibility. (5) Lighter weight compared to a thermoplastic film of the same thickness. (6) Excellent liquid retention, airtightness, and heat retention. (7) A uniform metal layer is formed on the film surface, and the vapor deposition surface has excellent gloss. (8) Since the metal layer is formed, it has excellent conductivity and electromagnetic wave shielding properties. (9) It is excellent in heat insulation, light shielding and light reflection. (10) Excellent gas barrier properties for oxygen and the like. (11) Excellent decorativeness.

The metal-deposited composite sheet of the present invention can be used for packaging materials such as electric materials such as conductive tapes, capacitors and electromagnetic wave shielding materials, foods, fresh vegetables, fresh flowers, fresh fish, fruits and vegetables, etc.
Household items such as microwave oven wraps, tempura oil suction sheets, dirt wipe sheets, cracks protection sheets, etc. clothes,
Warm clothes, work clothes, surgical clothes, surgical caps, clothing lining and other clothing items, tents, backpacks, rain gear, hats, gloves and other sports, leisure goods, greenhouses, weeding sheets, waterproof sheets, fruit bags, Fruit forcing cultivation sheet,
Agricultural materials such as sparrow threats, labels, stickers, reflective sheets, decorative items such as gold and silver thread, wallpaper, shoji paper, bran,
Architectural materials such as window glass protection sheets and house wraps,
It is possible to provide a material that can be suitably used and applied to industrial materials such as a pipe insulation protection sheet and an automobile interior sheet.

Continued on the front page F-term (reference) 3E086 BA04 BA15 BA19 BA40 BB90 CA01 CA35 4F071 AA43 AA43B AD06B AF19 AH01 AH04 AH12 CA03 CB08 CD02 CD07 4F100 AB01C AK41A AK41B BA03 BA07 BA10B BA10C DG15E03E03 GB03 E03 E03 GB03 E66 JB16A JD03 JD08 JJ02 JK06 JK17 JL03 JN21 YY00A YY00B

Claims (6)

[Claims] 1. A thermoplastic film and a non-woven fabric are bonded without interposing an adhesive, and a metal layer is formed on a surface of the film opposite to a bonding surface with the non-woven fabric. Metal composite sheet. 2. The metal-deposited composite sheet according to claim 1, wherein the thermoplastic film is a polyester film. 3. The metal-deposited composite sheet according to claim 1, wherein the thermoplastic film has a thickness of 1 to 100 μm. 4. The metal-deposited composite sheet according to claim 1, wherein the non-woven fabric is a polyester non-woven fabric. 5. The metal-deposited composite sheet according to claim 1, wherein the nonwoven fabric has a basis weight of ^{2 to} 200 g / m ² . 6. The metal-deposited composite sheet according to claim 1, wherein the non-woven fabric is made of fibers having a fiber diameter of 1 to 30 μm.