JPS627264B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a metallized film relating to metallization of the surface of a polymer film, and is capable of metallizing the surface of a polymer film having a smooth surface while maintaining the smoothness of the surface. More specifically, the method by which superior adhesion can be obtained relates to improvements in vacuum deposition. Although there is a common desire to metallize the surface of an insulating material, it is difficult to firmly attach a metal layer to the surface of the insulating material without roughening it. However, when depositing magnetic materials to produce magnetic recording media, it is important to maintain a smooth surface. The wet plating method, vacuum evaporation method, and a combination of these methods are known as methods for manufacturing magnetic tape by attaching a metal layer onto a commonly used biaxially stretched polyethylene terephthalate film, but it is difficult to obtain a smooth film. It is difficult to obtain satisfactory adhesion strength. To solve this problem, it has been proposed to apply an adhesion reinforcing layer or to combine it with known glow discharge treatment, corona treatment, etc., but current devices that record and play by sliding on a magnetic head have been proposed. What is important for application and durability is the scratch strength rather than the Sellotape peel strength, and the above-mentioned pretreatment is insufficient to improve this. The present invention aims to solve such problems by improving vapor deposition technology. An example of an apparatus for carrying out the present invention is shown in FIG. 1, and an example showing the importance of blocking is shown in FIG. This will be explained in detail.
A polymer film 1 to be metallized is placed in a vacuum chamber 4.
It is arranged opposite to the evaporation source 2. This polymer film 1
is arranged so as to move along the circumferential side of the cylindrical rotating can 3 (diameter 50 cm). When moving in the direction of the arrow, 7 schematically indicates a winding shaft and 8 schematically indicates a winding shaft. FIG. 1 is a minimum configuration diagram for explaining the elements necessary for the present invention, and following the production of the metallized film of the present invention, for example, Co,
By continuously depositing ferromagnetic materials such as Fe, Ni, or their alloys, it is possible to obtain magnetic recording media, and it goes without saying that it can also be used for other purposes, and each device is highly adaptable. should be designed, and the explanation is omitted here. There are no restrictions on the type or shape of the evaporation source 2, but
Since the industrially most excellent evaporation source is the electron beam heating method, most of the following examples used the electron beam heating method (16 Kw, 270 degree deflection type). In addition, the evaporation source 2 is located directly below the cylindrical rotating can 3.
It was placed at 30cm. However, the evaporation source 2 shown in FIG. 1 is schematically shown as a resistance heating type, and 10 is a heating power source and 11 is an insulated introduction terminal. 6 is a shielding plate and 9 is an adhesion prevention plate. The inside of the vacuum chamber 4 is continuously evacuated by a vacuum exhaust system 5. A new experiment in which there is a permissible limit on the maximum incident angle (the angle shown by θ in the figure) on the opposite side of the metal vapor flow emitted from the evaporation source 2 and the direction in which the polymer film 1 moves. The invention is based on this fact. This angle shows almost no dependence on the material, and there is no noticeable dependence on the deposition rate even up to several tens of μ/min. Although the present invention shows that it is sufficient to block the maximum incident angle by 60° or more, it is necessary to cut off the maximum incident angle by 60° as much as efficiency allows, taking into consideration the vapor deposition conditions, vapor deposition specifications, heat resistance of the polymer film 1 that is the base material, etc. It may be possible to cut off the angle to less than 40°, but from an industrial perspective, this is actually more stable, and depending on the geometry of the vapor deposition equipment, it is appropriate to cut off to about 40° in many cases. Regarding the fact that it is sufficient to block the component with an incident angle of 60° or more of the metal vapor flow, the size of the cylindrical rotating can 3 was confirmed to be 30 cm, 1 m, and 1.2 m in diameter, and the evaporation source position was changed to the cylindrical rotating can. From 15cm to 50
This was also confirmed when the central axis of the evaporation source was shifted from the central axis of the cylindrical rotating can. As described above, within the range of normal production scale, the incident angle changes momentarily along the cylindrical rotation can, resulting in curved growth of columnar crystals.
(from 90 degrees to 60 degrees), the crystal becomes thinner and 90 degrees
If the temperature is close to 300 degrees, some metal particles will cause total reflection, so
It is unstable and easily detaches from the polymer film when stress is applied. It is thought that by blocking this part, the Wander Waals force with the polymer film will increase, and the gaps between crystal grains will become smaller, making it difficult for adjacent grains to move, making them more resistant to stress. It will be done. The present invention does not preclude interruptions other than the above-mentioned interruption of 60 degrees or more, and it is of course possible to perform interruptions for other purposes, and this does not have a primary effect on the effects of the present invention. Incidentally, it is naturally possible to use it in combination with a known pretreatment, and as confirmed in several examples, it also has a secondary effect on the effects of the present invention, and it is also possible to apply the present invention to ion plating. It was found to have a similar effect, and was not as direct as the impact strength improvement effect of the present invention. Next, specific examples are shown in the table below.

【table】

[Table] Other polymer films such as polyethylene 2.6 naphthalate, polyamide, polycarbonate, and metal materials for vapor deposition include Ag, W, Ni, Co,
The effects of the present invention were also confirmed for Fe, Pd, Si, Sn, In, Al, etc. FIG. 2 shows an example in which a magnetic recording medium was manufactured using the present invention and excellent effects were confirmed. Polyethylene terephthalate film (thickness 10
μ), Mo was electron beam evaporated at different incident angles of 500 Å, and Co was deposited on them in oxygen at 5 × 10 ^-5 Torr.
Deposit 1500Å, record a sine wave with a recording wavelength of 1μ,
Figure 2 shows the results of repeated running and the number of runs at which the head output decreased by 1 dB.
As is clear from Fig. 2, there is a critical change depending on the angle of incidence, and the existence of the critical angle can be seen at approximately 60°. As described above, according to the present invention, the adhesion of a metal layer on a smooth polymer film can be greatly improved, and its industrial efficiency is great when it is used in the production of magnetic recording media, etc. be. It should be noted that the present invention is not necessarily limited to application to smooth polymer films, and the effect is great even when applied to metallization of ordinary polymer films.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a vapor deposition apparatus in an embodiment of the method for producing a metallized film of the present invention, and FIG. 2 is a characteristic diagram showing the incident angle of vapor deposition and running life of the metallized film obtained by the same method. . 1... Polymer film, 2... Evaporation source, 3...
Cylindrical rotating can, 4...vacuum chamber, 6...blocking plate.

Claims (1)

[Claims] 1. When manufacturing a metallized film by directing a metal vapor flow to a polymer film moving along the circumferential side of a cylindrical can in a vacuum atmosphere, the direction of the metal vapor flow and the direction of movement of the polymer film are A method for producing a metallized film characterized by blocking components of metal vapor flow at an incident angle of 60° or more on the opposing side.