JPH0555596B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a metal vapor deposited film that has a metal aluminum layer with excellent adhesion that does not peel off from a base film and exhibits high gas barrier properties. (Prior art) Recently, metal-deposited films have excellent light reflectivity,
Because it has light blocking properties and gas blocking properties, it is often used for applications that take advantage of its surface gloss and for packaging materials. However, these conventional metallized films
The adhesion of the metal vapor deposited layer to the base film is poor,
It has the disadvantage that it peels off more easily than the film surface. Therefore, in order to solve these drawbacks,
Various methods have been proposed. For example, the surface of the plastic may be roughened in advance by a physical or chemical method, or it may be subjected to electrical corona discharge treatment or glow discharge treatment. However, these methods do not provide sufficient adhesion strength for practical use, and their uses are limited. Therefore, in order to solve this problem, attempts have been made to apply a thin layer of adhesive or the like to the surface of the film in advance. (Problems to be Solved by the Invention) However, the following problems occurred with the film in which such an adhesive was applied in advance and then metal aluminum was vacuum-deposited. That is, a. An adhesive must be applied to the surface of the film before vacuum deposition, which complicates the process and increases costs. b Depending on the type of base film, there are various problems such as being unable to perform sufficient curing due to heat shrinkage due to restrictions on coating conditions. Again, the adhesive strength is insufficient and it cannot be used for some purposes. c Since there is an adhesive layer between the plastic film and the metal vapor deposited layer, the heat resistance of the adhesive layer is lost when exposed to a high temperature atmosphere, and as it moves, the aluminum vapor deposited film loses its luster. There is a big problem of losing and bleaching. d Particularly when metallized film is used as a packaging material, heat sealing is essential in the bag making and filling processes after lamination, but generally the lamination strength of the heat sealed part is higher than that of thermocompression bonding. However, the type coated with adhesive in advance is not sufficient to prevent this deterioration mainly due to the reasons mentioned in items b and c above, and heat sealing is not sufficient to prevent this deterioration. The degree of whitening and discoloration at the stop is also large. The object of the present invention is to avoid the above-mentioned drawbacks, i.e., to have a stronger adhesion to vapor-deposited aluminum than before without losing its metallic luster, even during high-temperature use, and thus to achieve a high level of stable laminate strength. It is an object of the present invention to provide a metal-deposited film that can obtain the following characteristics, can almost completely prevent a decrease in the laminate strength of a heat-sealed part, and has excellent gas barrier properties, and a method for producing the same. (Means for Solving the Problems) That is, an object of the present invention is to form a metal aluminum vapor deposition layer on at least one side of a plastic film via an aluminum oxide vapor deposition layer formed by a reaction between metal aluminum vapor and oxygen gas. metallized film.
and forming an aluminum oxide vapor deposition layer on at least one side of the plastic film by a reaction between metal aluminum vapor and oxygen gas while the plastic film is running in the same vacuum container, and subsequently forming a metal aluminum vapor deposition layer on the aluminum oxide vapor deposition layer. A method for producing a metallized film in which a layer is formed by vacuum deposition. This can be achieved by The plastic film used in the present invention includes polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, nylon 6,
Polyamides such as nylon 12, aromatic polyamides,
Polyimide, etc. Furthermore, the material for the plastic film in the present invention may be the above-mentioned polymers or copolymers with other organic polymers. Further, these organic polymers may be melt-extruded or uniaxially or biaxially stretched depending on the use, and are not particularly limited. In addition, these organic polymers can be used as antistatic agents, ultraviolet absorbers, colorants, heat stabilizers,
An internal lubricant or the like may be added. The plastic film used in the present invention may have mechanical strength, thermal dimensional stability, etc. suitable for use as a plastic vapor-deposited film material. These plastic films may be subjected to surface treatment such as corona discharge treatment or plasma treatment, or surface roughening treatment by physical or chemical methods without causing any problems, prior to the formation of the aluminum oxide layer. Additionally, in order to improve adhesion, adhesive may be applied in advance using a known method, but it is necessary that the adhesive is suitable to not cause the whitening phenomenon mentioned above at high temperatures. be. The thickness of the plastic film of the present invention is not particularly limited, but is preferably from 2 to 250 μm in terms of flexibility, thermal properties, and mechanical properties, and from 9 to 125 μm.
More preferably, the range is m. Aluminum oxide in the present invention refers to AlO,
Aluminum oxides such as Al ₂ O ₂ and Al ₂ O ₃ .
Further, other impurities may be included in the aluminum oxide layer within a range that does not impair adhesion. Further, the aluminum oxide in the present invention is preferably amorphous since it exhibits flexibility and formability. If crystalline aluminum oxide is contained, cracks will occur in the film when the film is made thick or bent, which is not preferable. Note that crystallinity or non-crystallinity can be easily determined using an ordinary X-ray diffraction apparatus. That is, the amorphous aluminum oxide in the present invention means one in which no specific diffraction is observed by X-ray diffraction. The thickness of the aluminum oxide adhesion layer is preferably selected depending on the base film, intended use, etc., and is generally in the range of 20 to 1000 Å in order to improve the adhesion of the metal aluminum vapor deposited layer. More preferably, it is 50 to 300 Å. If the thickness of the aluminum oxide adhesion layer is less than 20 Å, the adhesion of the subsequently laminated aluminum evaporated layer will not be sufficient and
In the above case, iris coloration occurs due to light interference, which is not preferable. The method for forming the aluminum oxide adhesive layer is as follows:
A method in which aluminum oxide powder or solid material is vacuum-deposited by vacuum evaporation, sputtering, ion plating, etc., or a method in which aluminum metal and oxygen gas are introduced and formed by the above-mentioned vacuum evaporation method can be adopted. Alternatively, aluminum may be thinly deposited in advance by a known method and oxidized later. In the present invention, the metal aluminum adhesion layer is formed by a conventional method. The thickness of the aluminum adhesion layer is not particularly limited, but
Depending on the purpose, the range is preferably such that sufficient surface gloss, electrical conductivity, light blocking properties, gas blocking properties, etc. can be obtained. Further, the present inventors have developed the following method as an economically efficient method for providing such an aluminum oxide vapor deposited layer and a metal aluminum vapor deposited layer. That is, in the vapor deposition apparatus as shown in FIG. 2, when the plastic film 1 is vacuum-deposited along the cooling drum 12, the gas flow controller 9 is used at the beginning of the vapor-deposition part to control the oxygen in the oxygen cylinder 10. In this method, gas is introduced through the gas outlet 8 to form an aluminum oxide vapor deposited layer by reactive vapor deposition, and in the latter part, a normal aluminum layer is formed without introducing oxygen. If this method is used, just like the conventional method of vacuum-depositing only aluminum, by controlling the position of the gas outlet 8 and the flow rate of oxygen gas, it is possible to easily separate the aluminum oxide-deposited layer and the metal aluminum-deposited layer. Two layers can be formed continuously with high thickness accuracy. (Function) The metal-deposited film according to the present invention has a strong adhesion of the metal-aluminum deposited layer, and there is no whitening phenomenon due to heat, so it can be used for packaging such as various retort applications.
It can be used for labels, gold and silver thread, various decorations, electrical parts, etc. In addition, the metallized film according to the present invention can be laminated with other materials, bonded,
Printing of characters, designs, etc., surface protection coating, etc. can be carried out as appropriate. (Example) The present invention will be explained below with reference to Examples. In addition,
The following method was used to measure and evaluate the characteristics. B Crystallinity of aluminum oxide vapor deposited layer
Kα rays (using a Ni filter) were applied to the surface of the deposited layer, and the diffraction intensity was measured using a scintillation counter (manufactured by Rigaku Denki Co., Ltd.) while rotating the sample and X-ray source using a goniometer. (b) Composition analysis of aluminum oxide vapor deposited layer The vapor deposited layer was analyzed with an ESCA spectrometer (ESCA750 manufactured by Shimadzu Corporation), and the aluminum oxide composition was confirmed from the bonding energy of the Al2P spectrum. C. Thickness of the aluminum oxide vapor deposited layer and metal aluminum layer.
No. 31B) (manufactured by Co., Ltd.) is pasted, and after being vapor-deposited on this, the adhesive tape is peeled off to create a step between the vapor-deposited part and the undeposited part. This step portion was measured using a high-precision step measuring machine (manufactured by Koita Research Institute, ET-10). Further, the metal aluminum vapor deposited layer was also measured by the same method. C. Adhesive strength of metal aluminum vapor deposited layer An aluminum oxide layer and further metal aluminum layer were vapor deposited on the plastic film, an adhesive was applied thereto, and after drying, the film was laminated with the plastic film. Thereafter, the two plastic films were peeled off, and the peeling force at that time was measured as the adhesion strength. Specifically, it is as described below. An aluminum oxide deposited layer and a metal aluminum deposited layer are sequentially formed on a plastic film, and the following composition is coated with 2 μm of adhesive on top of the plastic film. After drying at 80° C. for 1 minute, it is pressure-bonded with a 50 μm casting polypropylene film. Adhesive (1) Seikabond E-270 (manufactured by Dainichiseika Chemical Co., Ltd., urethane paint) 100 parts (2) Seikabond C-26 (manufactured by Dainichiseika Chemical Co., Ltd., isocyanate curing agent) 20 parts (3) Oxidation Ethyl 120 parts After aging the crimped sample at 40°C for 72 hours, cut it into 15 mm width pieces and use a Tensile Compression Tester (TCM-50 manufactured by Minebea Co., Ltd.) at a speed of 20 cm/min in a 90 degree direction. The adhesive was peeled off, and the peeling force at that time was measured as the adhesion strength. 2. Whitening An aluminum oxide vapor deposited layer and a metal aluminum vapor deposited layer were sequentially formed on a plastic film, and changes in the glossy surface of the film surface when heat treated were measured. Specifically, it is as described below. After sequentially forming an aluminum oxide vapor deposition layer and a metal aluminum vapor deposition layer on a plastic film and heat-treating the plastic film at 150°C for 5 minutes, the glossiness was measured using a digital variable angle photometer (manufactured by Suga Test Instruments Co., Ltd., UGV).
-4D). Example 1 A biaxially stretched polyethylene terphthalate film (12 μm thick) was formed into a roll having a width of 1000 mm and a length of 6000 m, and was mounted on the unwinding shaft 5 of a vapor deposition apparatus shown in FIG. Fill carbon crucible 7 with 800g of aluminum with a purity of 99.9%, and vacuum container 4 at 5.0×
Exhausted to 1.0 ^-4 Torr. Next, the aluminum in the carbon crucible 7 is melted using a high-frequency induction heating method, and the surface resistance is increased while the film 1 is running at 200 m/min.
Adjusted to 1.5Ω/□. Next, the gas flow controller 9 controls the oxygen cylinder 10.
The aluminum oxide vapor deposited layer 2 (FIG. 1) was formed while introducing oxygen gas through the gas outlet 8 at a rate of 8/min in terms of standard volume, and vapor deposition was continued for 30 minutes. Thereafter, the deposited film was taken out, and the sample was analyzed by X-ray diffraction and an ESCA spectrometer, and as a result, it was confirmed that it was amorphous aluminum oxide (Al ₂ O ₃ ). Next, the film on which aluminum oxide was vapor-deposited was mounted on the unwinding shaft 5 of the vapor deposition apparatus also shown in FIG. 800 g of aluminum with a purity of 99.9% was filled into the carbon crucible 7, and the vacuum container was evacuated to 5×10 ⁻⁴ Torr. Next, the aluminum in the carbon crucible 7 was melted using a high-frequency induction heating method, and the film was run at 250 m/min until the surface resistance value was 1.5 Ω/min.
The metal aluminum vapor deposited layer 3 was adjusted so that it became □. After continuing for about 10 minutes while controlling the amount of aluminum deposited, the deposited film was taken out. The results of evaluating the deposited film are shown in Table 2. Examples 2 and 3 The aluminum oxide vapor deposition layer 2 and the metal aluminum vapor deposition layer 3 were sequentially formed by the same method as in Example 1, and the conditions for forming the aluminum oxide vapor deposition layer 2 are shown in Table 1. The conditions for forming the metal aluminum vapor deposited layer 3 were the same as in Example 1.

[Table] Example 4 Metallic aluminum was deposited on a biaxially stretched polyethylene terephthalate film (12 μm thick) using the deposition apparatus shown in FIG. At that time, after adjusting the surface resistance value of aluminum to 1.0Ω/□,
The vapor deposition was continued while introducing oxygen gas from the gas outlet 8 at a rate of 2/min in terms of standard volume using the gas flow rate control device 9. As a result of evaluating the deposited film, the thickness of the aluminum oxide deposited layer 2 between the base film 1 and the metal aluminum deposited layer 3 was uniform at 70 to 120 Å, but the thickness of the metal aluminum deposited layer 3 was 430 Å.
It was uniform. The adhesion strength was measured and was 250
It showed a high value of g/15mm. From this, it is clear that the case where the aluminum oxide vapor deposited layer 2 has a uniform thickness as in Examples 1, 2, and 3 in which the aluminum oxide vapor deposition layer 2 and the metal aluminum vapor deposition layer 3 are formed sequentially is better than the case where the aluminum oxide vapor deposition layer 2 has a uniform thickness. It can be seen that the example shows higher adhesion strength. According to cross-sectional observation using an electron microscope, in Examples 1, 2, and 3, in which the aluminum oxide deposited layer 2 and the metal aluminum deposited layer 3 were deposited sequentially, the aluminum oxide thin film layer was uniformly formed, as shown in FIG. On the other hand, the sample of this example had a large surface area as shown in FIG. Comparative Example 1 Surface resistance value was measured on polyethylene terephthalate (12 μm thick) in a vacuum of 5.0×10 ^-4 Torr at a running speed of 250 m/min without introducing oxygen gas.
An aluminum layer of 1.5Ω/□ was deposited. Examples 5, 6, 7 An aluminum oxide vapor deposited layer 2 and a metal aluminum vapor deposited layer 3 were formed on a casting polypropylene film (125 μm) by the same method as in Example 1.
were formed one after another, and the conditions for forming the aluminum oxide vapor deposited layer 2 at that time were changed. Example 8 An aluminum oxide vapor deposition layer 2 and a metal aluminum vapor deposition layer 3 were simultaneously formed on a casting polypropylene film (25 μm) by the same method as in Example 4. As a result, observation using an electron microscope revealed that the surface area was large as shown in FIG. Comparative example 2 Casting polypropylene film (25μ
m thickness) in a vacuum of 4.8×10 ^-4 Torr,
An aluminum layer having a surface resistance value of 1.4 Ω/□ was deposited at a running speed of 240 m/min without introducing oxygen gas. Table 2 shows the measurement results of the above examples and comparative examples.

【table】

[Table] (Effects of the Invention) The metal vapor deposited film according to the present invention has a feature that the adhesion of the vapor deposited layer to the base film is strong, and the surface gloss does not change in a high temperature atmosphere. Particularly when used as a packaging material, it is possible to produce products with a higher level and more stable lamination strength than conventional products at low cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG.
The figure is an explanatory view showing an example of a vapor deposition apparatus for implementing the present invention, and FIG. 3 is a sectional view showing another embodiment of the present invention. 1: Plastic film, 2: Aluminum oxide vapor deposition layer, 3: Metallic aluminum vapor deposition layer, 4:
Vacuum container, 5: Unwinding shaft, 6: Winding shaft, 7: Crucible, 8: Gas outlet, 9: Gas flow rate controller, 1
0: Oxygen cylinder, 11: Mask, 12: Cooling drum.

Claims (1)

[Claims] 1. On at least one side of the plastic film,
A metal vapor-deposited film characterized in that a metal aluminum vapor-deposited layer is formed through an aluminum oxide vapor-deposited layer formed by a reaction between metal aluminum vapor and oxygen gas. 2. The metal vapor deposited film according to claim 1, wherein the aluminum oxide constituting the aluminum oxide vapor deposited layer is amorphous. 3. While the plastic film is running in the same vacuum container, an aluminum oxide vapor deposition layer is formed on at least one side of the plastic film by a reaction between metal aluminum vapor and oxygen gas, and then a metal aluminum vapor deposition layer is formed on the aluminum oxide vapor deposition layer. 1. A method for producing a metal-deposited film, characterized in that it is formed by vacuum deposition.