JP3293618B2 - Transparent vapor-deposited film and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION

The present invention relates to a transparent vapor-deposited film and a method for producing the same. More specifically, the present invention relates to a transparent vapor-deposited film having excellent gas barrier properties without a function of a metal oxide vapor-deposited layer being reduced by stress, and a method for producing the same.

[Prior art]

Vapor deposited films in which a vapor deposited layer of a metal or metal oxide is laminated on the surface of a polymer film substrate are well known (JP-A-49-15765, JP-A-49-34984, JP-A-1-252768,
JP-A-1-255661, JP-A-1-283136, JP-A-2-3433
0 publication). Films with a metallized layer are extremely excellent in terms of gloss, design, and gas barrier properties against oxygen, etc.Taking advantage of these characteristics, they are used in packaging materials for foods and pharmaceuticals. Expected. In addition, films having a metal oxide vapor deposited layer are generally transparent, are electrically insulating, and have excellent gas barrier properties for oxygen and the like, and are therefore also used for packaging materials such as foods.
Its use is also expected to expand.

[Problems to be solved by the invention]

However, these deposited layers are cracked by stress and lose their functions. The stress may be caused by various causes, for example, bending of the deposited film. In addition, the polymer film substrate is softened or shrunk by secondary processing using heat, such as heat sealing for bag making, drying of adhesive when bonding with other films, drying of printing ink during printing, etc. Also occurs when doing. Due to the stress, minute cracks (microcracks) occur in the deposited layer, and gas barrier properties are generally lost. In the case of a metal vapor deposition layer, the vapor deposition layer becomes white due to microcracks in the vapor deposition layer, or a rainbow pattern is generated by diffraction of light rays at the crack edges, thereby losing the original metallic luster. Further, the deposited layer itself may be peeled off from the polymer film substrate due to stress. Therefore, the present invention provides a transparent vapor-deposited film having excellent gas barrier properties with excellent adhesion strength to a polymer film substrate without occurrence of cracks due to stress and accompanying deterioration of the function of the transparent vapor-deposited layer, and a method for producing the same. The purpose is to provide.

[Means for Solving the Problems]

In order to achieve this object, the invention described in claim 1 is:
On a polymer film substrate, a metal oxide vapor-deposited layer selected from magnesium, silicon, aluminum, or tin, an oxidized or non-oxidized polyolefin having a molecular weight of 1,000 to 60,000 or a hydrocarbon vapor-deposited layer made of higher paraffin is provided. A transparent vapor-deposited film having excellent gas barrier properties is provided. The invention according to claim 2 continuously runs the polymer film substrate through a cooling roll in a vacuum atmosphere,
Below this cooling roll, a source of a metal oxide selected from magnesium, silicon, aluminum, or tin sequentially arranged along the running direction of the polymer film substrate,
Production of transparent vapor-deposited film with excellent gas barrier properties, characterized by evaporating the evaporant from a hydrocarbon source consisting of polyolefin or higher paraffin having a molecular weight of 1,000 to 60,000 and continuously depositing it on a running polymer film substrate Provide a way.

BEST MODE FOR CARRYING OUT THE INVENTION

As shown in the sectional view of FIG. 1, the transparent vapor-deposited film (1) according to the present invention comprises a polymer film substrate (1a), a vapor-deposited layer of metal oxide (1b), an oxidized or unoxidized hydrocarbon. And a vapor deposition layer (1c). The polymer film substrate (1a) consists of a vapor-deposited layer (1b) and (1c)
A polyolefin such as polyethylene or polypropylene: a polyester such as polyethylene terephthalate or polyethylene naphthalate; nylon-6;
Polyamides such as nylon-12; polycarbonates; polyvinyl chloride; polyimides; polysulfones; polyetherimides; Further, a multilayer film formed by laminating two or more kinds of films selected from these films with each other may be used. The polymer film substrate (1a) may contain additives and stabilizers such as an antistatic agent, an ultraviolet absorber, a plasticizer, a lubricant, and a coloring agent, depending on the material. The thickness of the polymer film substrate (1a) may be arbitrary, but is usually 6 to 200 μm. From the point of handling such as no wrinkles during processing and mechanical strength 12
100100 μm is preferred. The polymer film substrate (1a) may be either a sheet-like film or a long film, but the metal oxide vapor deposition layer (1b) and the hydrocarbon vapor deposition layer (1c) are continuously and efficiently formed. A long film is preferred for lamination. This polymer film substrate (1a) can be subjected to a physical or chemical surface treatment prior to the deposition of the vapor deposition layer (1b). For example, there are a corona discharge treatment, a flame treatment, an ozone treatment, a plasma discharge treatment, and the like. Prior to lamination of the vapor-deposited layer (1b), the polymer film substrate (1a) is provided with an anchor coat layer to improve the adhesion between the metal oxide vapor-deposited layer (1b) and the polymer film substrate (1a). Can be given. Examples of the anchor coat layer include thermoplastic resins such as polyester, polyurethane, polyvinyl chloride, polyvinyl chloride-vinyl acetate copolymer and nitrocellulose; thermosetting resins such as melamine resin or urea resin; polyurethane acrylate, polyester acrylate, An ultraviolet or electron beam curable resin such as epoxy acrylate can be used. The metal oxide deposited layer (1b) bears the original function of the deposited film (1). The metal oxide vapor-deposited layer (1b) can provide a vapor-deposited film that is transparent and has excellent gas barrier properties against oxygen and water vapor. Aluminum, tin, zirconium, zinc, copper, chromium,
Examples include metal oxides composed of iron, cobalt, nickel, silver, magnesium, silicon, and the like. Preferred metal oxides include oxides of magnesium, silicon, aluminum and tin. The thickness of the metal oxide deposited layer (1b) varies depending on the intended use of the deposited film (1), but in order to obtain gas barrier properties such as oxygen, a thickness of about 500 Å or more is required. good. Usually less than 2000 Angstroms. The hydrocarbon deposition layer (1c) prevents cracks from occurring in the metal oxide deposition layer (1b) due to stress. However, the reason is not clear. The hydrocarbon deposition layer (1c) is formed by depositing a relatively low molecular weight polyolefin having a molecular weight of 1,000 to 50,000 or higher paraffin from its source. For example, the 2900～2950,1460,1380,720Cm ^-1 as an infrared absorption peak C-
It is a hydrocarbon having a peak due to an H bond or (CH) _n . Thus, the hydrocarbon deposited layer (1c) is composed of unoxidized low molecular weight polyolefin or higher paraffin,
May be oxidized during deposition. Such oxidation does not affect the function of the hydrocarbon deposition layer (1c). Of course,
It is also possible to oxidize intentionally. In order to intentionally oxidize, the surface of the hydrocarbon deposition layer (1c) may be treated with plasma of an oxidizing gas. Metal oxide, evaporation layer (1b) and hydrocarbon evaporation layer (1c)
It is desirable that the boundary surface is clear, but the boundary surface may not be clear due to the vapor deposition method. In other words, in this case, “the deposited layer of the metal oxide (1b) / the deposited layer of the mixture of the metal oxide and the hydrocarbon / the deposited layer of the hydrocarbon (1c)”
Has a layer configuration of As described above, even when the boundary surface is unclear, cracks due to stress do not occur. Metal oxide deposited layer (1b) and hydrocarbon deposited layer (1c)
Is sufficient if its total thickness is 500 to 5000 angstroms. The metal oxide deposited layer (1b) and the hydrocarbon deposited layer (1c) can be continuously formed on the polymer film substrate (1a). Another resin layer may be further laminated on the vapor deposition layer surface of the vapor deposition film (1) to form a protective layer on the vapor deposition surface or a heat seal layer for bag making. Polyolefin such as polyethylene and polypropylene can be used for the resin layer. Lamination may be performed by dry lamination using a urethane-based adhesive or the like. It is also possible to laminate these resins by melt extrusion lamination on the deposition surface. FIG. 2 is an explanatory view showing an example of an apparatus for continuously forming a metal oxide deposited layer (1b) and a hydrocarbon deposited layer (1c). That is, in FIG. 2, the polymer film substrate (1
In order to form the vapor deposition layer (1c) (1c) on a),
It must be maintained at a vacuum of 0 to 10 torr. In order to maintain a vacuum state, vacuum suction may be performed from the exhaust system (16), and the pressure can be constantly measured by the vacuum gauge (300). Also, since it is necessary to form (1b) and (1c) continuously,
The polymer film substrate (1a) is long and is wound around an unwinding roll (5). The polymer film substrate (1a) is unwound from the unwinding roll (5),
While hugging the cooling roll (7), pass around it,
It is taken up by a take-up roll (6). Between the unwinding roll (5) and the cooling roll (7), a dancer roll (2), a guide roll (3), It is desirable to arrange an expander roll (4) and the like. For the same reason, it is desirable to arrange an expander roll (4), a guide roll (3), and a dancer roll (2) between the cooling roll (7) and the winding roll (6). In order to form a vapor deposition layer (1b) (1c) having a uniform thickness continuously, the polymer film substrate (1a) needs to run continuously from the unwinding roll (5) to the winding roll (6). There is. The chill roll (7) contains the vaporized material evaporated from the sources (9) (10), ie, metal oxide (12), hydrocarbon (1).
3) adheres well to the polymer film substrate (1a) and prevents the polymer film substrate (1a) from being damaged by heat; therefore, the source (9) of the metal oxide (12) , And the source (10) of hydrocarbons (13) must all be located below this chill roll (7). In addition, the vapor deposition layer (1b) is first formed on the metal oxide on the polymer film substrate (1a), and then the hydrocarbon film deposition layer (1c) is formed. , It is necessary to sequentially arrange the source (9) of the metal oxide (12) and the source (10) of the hydrocarbon (13). The vapor deposition can be performed by any method, for example, by a resistance heating method. (8) and (80) indicate the evaporation source power for heating the source (9) of the metal oxide (12) and the source (10) of the hydrocarbon (13), respectively. The source (9) and the source (10) can be arranged without partitioning each other. However, the metal oxide vapor deposition layer (1b) and the hydrocarbon vapor deposition layer (1c) are formed by forming a boundary between them. For clear formation, it is desirable to provide a partition plate (200) between the source (9) and the source (10). The partition plate (200) is desirably provided up to a height at which it contacts the polymer film substrate (1a), but if it comes into contact with the polymer film substrate (1a), the smooth running of the polymer film substrate (1a) is hindered. The distance may be such that the traveling of the base (1a) is not hindered. As a result of mixing of the vapor of the metal oxide and the vapor of the hydrocarbon from the gap between the polymer film substrate (1a) and the partition plate (200), a “metal oxide vapor deposition layer ( 1b) / a deposited layer of a mixture of a metal oxide and a hydrocarbon / a deposited layer of a hydrocarbon (1c). In addition, a shielding mask (11) is provided around the sources (9) and (10) in order to specify a region where vapor deposition is performed and to easily control the film thickness. In the example shown in the figure, deposition rate monitors (14) and (15) are provided to detect the deposition rate of the metal oxide and the deposition rate of the hydrocarbon. This monitor (14)
(15) By detecting the evaporation rate and controlling the running speed and evaporation rate of the polymer film substrate (1a), the thickness of the metal oxide vapor deposition layer (1b) and the hydrocarbon vapor deposition layer (1c) Can be controlled. In addition, the apparatus shown in FIG. 2 is provided with equipment (17) for oxidizing the surface of the deposited film (1) on which the deposited layers (1b) and (1c) are formed. This equipment is intended to intentionally oxidize the hydrocarbon vapor deposition layer (1c), and converts the oxidizing gas supplied through the mass flow controller into a plasma to be brought into contact with the hydrocarbon vapor deposition layer (1c). Things. As the oxidizing gas, air, oxygen, carbon dioxide or the like can be used. Further, a mixed gas of a non-oxidizing gas such as nitrogen and an oxidizing gas may be used. Plasma can be generated by a high-frequency electric field supplied from a power supply (18) or a microwave. The plasma can be efficiently guided to the deposition surface by a magnet provided inside the facility. FIG. 3 shows that the entire vapor deposition apparatus is divided into two chambers, and cooling rolls (7) are separately provided in each chamber, and a metal oxide vapor deposition layer (1b) and a hydrocarbon vapor deposition layer are provided on each cooling roll. The polymer film substrate (1a) is formed by forming the two cooling rolls (7) through a seal roll (500).
(7) While running continuously, both cooling rolls (7)
Between (7), a partition plate (200) is provided. Further, in the apparatus shown in FIG. 3, equipment for oxidizing the evaporation surface of the evaporation film (1) is not provided, but equipment for performing surface treatment on the polymer film substrate (1a) before evaporation is provided. I have. Since the vapor deposition is performed when the film is wound around the cooling roll (7), the surface treatment equipment for the film substrate (1a) needs to be arranged before the cooling roll (7).
In FIG. 3, (19) is a surface treatment facility, which applies a high-frequency electric field to a processing gas supplied through a mass flow controller to turn it into plasma, and performs surface treatment with the plasma. As the gas, air, oxygen, carbon dioxide, argon or the like can be used. In order to facilitate the generation of plasma, the inside of the processing equipment is maintained in a high vacuum state of 10 ^-2 to 10 ^-4 torr. (20) in the figure is a power supply for a high-frequency electric field. Microwaves may be used instead of the high-frequency electric field.

【Example】

(Example 1) (a) Polymer film substrate (1) Material polyethylene terephthalate film (2) Thickness 12 μm (3) Shape wound (b) Metal oxide MgO (4N) (manufactured by Kojundo Chemical Co., Ltd.) c) Hydrocarbon low-density polyethylene (Mirason M-14P, manufactured by Mitsui Polychemicals, Inc., molecular weight 30,000) (d) Evaporation method (1) Evaporation apparatus Apparatus shown in Fig. 2 (2) Degree of vacuum 9 × 10 ^-6 torr (3) Heating method Both MgO and low-density polyethylene are heated by electron beam. (4) MgO heating conditions Acceleration voltage 6 kV, emission current 50 mA (5) Hydrocarbon heating conditions Acceleration voltage 4 kV, emission current 15 mA (6) MgO Evaporation rate measurement method Monitoring speed using a quartz oscillation type thickness gauge 25 ± 1Å / sec (Because it is difficult to measure the thickness of the hydrocarbon with this thickness gauge, the thickness of the hydrocarbon deposited film is not measured. Based on experimental results Fastened to set the deposition conditions Te) (7) without processing the travel speed 1 m / min (8) FIG. 1 (17). (E) Evaporated film (1) Colorless and transparent (2) Thickness of evaporated layer Measurement method Transmission electron microscope MgO 2000Å Hydrocarbon 2000Å (3) Evaporation composition Oxygen (O), carbon (C), magnesium (Mg) (4) ) due to the asymmetric and symmetric stretching of the infrared absorption peak structure measuring method deposited film outermost layer of the hydrocarbon vapor deposited layer measured peak · 2900~2950cm ^-1 (aliphatic C-H) · 1460cm ^-1 (odd of C-H 1380cm ^-1 (caused by (CH) n eccentric extension) ・ 720cm ^-1 (caused by (CH) n eccentric extension) (5) Surface contact Angle Measurement method Measured with a goniometer-type Elma contact angle measuring device manufactured by Elma Optical Co., Ltd. Contact angle 120 degrees (extremely high hydrophobicity) (f) Laminated film (1) Production method 34dyne / cm
(Measured according to JISK6768), then adhere unstretched polypropylene (thickness 60μm) via urethane type adhesive. (2) Oxygen permeability measurement method Measured with MOCON OX-TRAN-1 10 / 50A Transmittance 0.9 ml / m ² · atm · day (3) Water vapor permeability measurement method Measured with MOCON TPERMATRAN W-6 Transmittance 0.9 g / m ² · day (4) Peel strength measurement method Peel off the polypropylene film and measure its strength Measurement conditions Measuring instrument TENSILON UTM-III-100 (TOYO BALDWIN Co., Ltd) Method T-peeling Peeling speed 300mm / min Result Measurement was not possible because the polyethylene terephthalate film was broken at a width of 400 g / 15 mm. (6) Physical properties after stress Method of applying stress Stress was applied using a gelboflex tester manufactured by Rigaku Kogyo Co., Ltd. Oxygen permeability 0.9 to 1.0 ml / m ²・ Atm ・ day Water vapor transmission rate 0.5 ~ 0.6g / m ²・ day Peel strength 350g / 15mm width (g) Summary The above results are summarized in Table 1. Example 2 The same experiment as in Example 1 was performed except that the discharge treatment in FIG. 2 (17) was performed. (A) Discharge conditions Vacuum degree of the discharge box 1.6 to 2.0 × 10 ^-4 torr. Electrode Rod electrode with permanent magnet inside Gas Mixed gas of nitrogen gas (90 mol%) and carbon dioxide gas (10 mol%) Voltage 600-605V Current 520-522mA (b) Result Contact angle of vapor deposition surface 62 degrees Wetting index of vapor deposition surface 43dyne / cm From this result, it can be seen that the hydrocarbon vapor deposition layer is oxidized. The other results are shown in Table 1. Example 3 An experiment was performed in the same manner as in Example 1 except that SiO (3N, manufactured by Osaka Titanium Co., Ltd.) was used instead of MgO. The physical properties of the obtained deposited film and laminated film are
It is shown in the table. A bag was prepared using the laminated film, filled and sealed with 120 ml of water, and subjected to a retort treatment at 125 ° C. for 30 minutes. As a result, no change was observed in oxygen permeability, water vapor permeability, and peel strength. (Comparative Examples 1 and 2) An experiment was performed in the same manner as in Examples 1 and 3, except that the hydrocarbon deposition layer was not provided. The results are also shown in Table 1.

【The invention's effect】

As described above, according to the first aspect of the present invention, there is no occurrence of cracks due to stress, and there is no reduction in the barrier function of the vapor-deposited layer due to the cracks, and the electrical insulation with excellent adhesion strength to the polymer film substrate. A transparent vapor-deposited film can be provided. Further, according to the invention of claim 2, the transparent vapor-deposited film of the invention of claim 1 can be continuously manufactured in the same chamber.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a vapor deposition film of the present invention, and FIGS. 2 and 3 are explanatory views for explaining a method of manufacturing the same. DESCRIPTION OF SYMBOLS 1 ... Evaporation film 1a ... Polymer film base 1b ... Evaporation layer of metal oxide 1c ... Hydrocarbon evaporation layer 2 ... Dancer roll 3 ... Guide roll 4 ... Expander roll 5 ... Unwind roll 6 winding roll 7 cooling roll 8 evaporation source power 9 metal oxide source 10 hydrocarbon source 11 shielding mask 12 metal oxide 13 hydrocarbon 14 15 Evaporation rate monitor 16 Exhaust system 17 Oxidation treatment equipment 18, 20 Power supply 19 Surface treatment equipment 80 Evaporation source power 200 Partition plate 300 Vacuum gauge

Continuation of the front page (51) Int.Cl. ⁷ identification code FI C23C14 / 56 C23C14 / 56 (56) References JP-A-58-164778 (JP, A) JP-A-62-51028 (JP, A) JP-A-61-258333 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-33/00 C23C 13/00-14/56

Claims (2)

(57) [Claims] 1. A polymer film substrate comprising: magnesium,
Metal oxide deposited layer selected from silicon, aluminum, or tin, oxidized or non-oxidized molecular weight 1000-
A transparent vapor-deposited film with excellent gas barrier properties, provided with a hydrocarbon vapor-deposited layer composed of 60,000 polyolefins or higher paraffins. 2. A polymer film substrate is continuously run through a cooling roll in a vacuum atmosphere, and magnesium, silicon, and aluminum are sequentially arranged below the cooling roll along a running direction of the polymer film substrate. Or a source of a metal oxide selected from tin, and a molecular weight of 1,000 to 60,000
A method for producing a transparent vapor-deposited film having excellent gas barrier properties, comprising evaporating an evaporating substance from a hydrocarbon source comprising polyolefin or higher paraffin and continuously depositing the vaporized substance on a running polymer film substrate.