JPH02132628A - Magnetic recording tape - Google Patents

Abstract

PURPOSE:To maintain enough mechanical strength and reproducing output even when the medium is made thin by providing thin film layers on both sides of a polymer film substrate and providing a magnetic coated layer on at least one side thereof. CONSTITUTION:The thin film layers 2a, 2b consisting of beryllium oxide are formed on both sides of the polymer film substrate 1 with specific thickness by vacuum vapor deposition. On one side of the substrate, a magnetic coating material consisting of magnetic powder dispersed in a binder is applied to form the magnetic coating layer 3 with specific thickness. On the other side, a back coating layer 4 with specific thickness is formed by a conventional method. Since the thin layers 2a, 2b are formed by vacuum vapor deposition, they are as thin as about 0.1mum thick. The magnetic recording tape thus formed has large resistance to elongation and improved mechanical strength and can endure high load. Though the medium is thin, it has enough reproducing output.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an FFI recording tape used as a LA recording medium in a video tape recorder.

Conventional technology The basic structure of conventional thin coated magnetic recording tapes for high-density recording is to coat one side of a polymer film such as polyethylene terephthalate (PET) with magnetic paint, which is a mixture of magnetic particles and a binder. The other two surfaces are coated with a back coat layer and coated with magnetic N.
It has a layered structure.

Problem to be Solved by the Invention However, with such a groove structure, as the total thickness of the magnetic recording tape becomes thinner, the rigidity decreases.
The relative speed between the tape and the head is 3.0 μm compared to a magnetic recording tape with a total thickness of 13 μm. 8m/
x. 0. In 75 pm sine wave recording and reproduction,
Tape TA! Due to the decrease in I property, the contact with the head is poor and the envelope shape is poor, resulting in a loss of 0.5 to 1 dB.
A phenomenon such as low output occurs. In this way, by further reducing the tape thickness to 10 μm or less, the mechanical strength decreases and the recording and reproducing output decreases. This has been addressed by increasing the strength (Japanese Unexamined Patent Publication No. 112630/1983). However, as the thickness becomes even thinner, the strength that can be achieved with polymer film becomes insufficient, and improvements have been desired.

The present invention is intended to solve the above problems, and aims to provide a magnetic recording tape that maintains sufficient mechanical strength and recording/reproducing output even when the thickness is reduced.

Means for Solving the Problems In order to solve the above-mentioned problems, the magnetic recording tape of the present invention is provided with thin film layers on both sides of a substrate made of a polymer film,
In addition, at least one side of the magnetic layer is coated with K.

Function: In the magnetic recording tape of the present invention, thin film layers are provided on both sides of the substrate made of polymer film, so even when the polymer film is made thinner to obtain a thin magnetic recording tape, Mechanical strength is maintained, tape rigidity does not decrease, and problems such as deterioration of the mechanical bellows shape due to deterioration of head contact and output reduction are eliminated, and short wavelength recording and reproduction characteristics of thin coated magnetic recording tapes are improved. be done.

EXAMPLE Hereinafter, a magnetic recording tape according to an example of the present invention will be explained with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of the main parts of a magnetic recording tape according to an embodiment of the present invention.

As shown in FIG. 1, thin film layers 2a and 2b made of perylium oxide are formed by vacuum evaporation on both sides of a substrate 1 made of a polymer film with a thickness of 4 to 10 μm as a magnetic recording tape for an 8-ga video tape recorder. Then, on one side, a magnetic paint containing magnetic particles mixed in a binder was applied to form a coated magnetic layer 3t with a thickness of 3 μm, and on the other side, a back coat layer 4 with a thickness of 0.8 μm was formed by a conventional method. did. Since the thin film layers 2a + 2b are formed by vacuum evaporation, they have a thickness of only about 0.1 μm, and the total thickness of the magnetic recording tape is compared with that of a coated magnetic recording tape manufactured by a conventional manufacturing method. Even if it is, the thickness will only increase by 0.2 μm. The mechanical strength of both is determined by the thickness of base 1 being 8 μm.
m, the elongation rate is 0.54. 1%, 2 壬. FIG. 2 shows a comparison of the stress when the load is 5. On both sides of the substrate 1 at each point are thin film layers 2a.
The magnetic recording disk of the wooden example in which 2b was formed had greater tensile resistance. The mechanical strength has been improved by about 20%, and it can withstand higher loads than conventional coated magnetic recording tapes. Also, for both magnetic recording tapes with different overall thicknesses, the relative speed between the tape and the head was 3.8 m7%. ，
The recording and reproducing output of a sine wave with a wavelength of 0.75 μm was measured, and the results are shown in FIG.

As is clear from FIG. 3, in the magnetic recording tape of this example, sufficient output was obtained even when it was thin.

In this embodiment, polyethylene terephthalate (PET) is used as the polymer film of Basic 1, and thin film layers 2a. 2b was formed using pyridium oxide, but other materials such as 'ri, Cr, B. SiC +
A similar effect can be obtained using a material such as TiN.

However, the thin film layer 2a. A non-magnetic material is preferred to prevent 2bi self-demagnetization. Further, the thickness of the thin film layer 2ae2b is suitably 0.05 μm to 0.1 μm (0.1 μm to 0.2 μm in total for both sides) considering the balance between mechanical strength and magnetic recording data for long-term recording. . Thin film layer 2a. not only on one side but also on both sides. 2b is formed entirely in order to prevent Kerr/L/ (curvature of the tape surface) when subjected to thermal changes. Moreover, thin layer 2a. As a manufacturing method for 2b, in addition to the vacuum x-deposition method, a sputtering method, an ion plating method, etc. can be applied.

Effects of the Invention As described above, the magnetic recording tape of the present invention has good mechanical strength and rigidity, and the magnetic recording tape remains stable even when unexpectedly high loads such as dew condensation are applied when running it in a video tape recorder or the like. It has the advantages of not breaking, improving the durability of normal repeated running, and making it possible to make the base polymer film thinner, improving the practicality of magnetic recording tapes for long-term recording. Furthermore, the practicality of thin magnetic recording tapes in high humidity environments is also improved because stable head contact is ensured.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of the main parts of a magnetic recording tape according to an embodiment of the present invention, FIG. 2 is a diagram comparing the tensile resistance of the magnetic recording tape of the same embodiment and a conventional magnetic recording tape, and FIG.
The figure is a diagram comparing the sine wave recording and reproducing outputs of the magnetic recording device of the same embodiment and the conventional magnetic recording device. 1... Substrate, 2a. 2b... thin film layer, 3... coated magnetic layer.

Claims (1)

[Claims] 1. A magnetic recording tape characterized in that a thin film layer is provided on both sides of a substrate made of a polymer film, and a coated magnetic layer is provided on at least one side.