DE2304518A1 - MISALIGNED DISC FOR MAGNETIC RECORDING SYSTEMS - Google Patents

Description

Priority from % L ^ .i ^ £ Vt ^ £ ^ k21- ^{in USA} »due to the US application Serial No. 224.187

The invention relates to magnetic disk recording systems and particularly relates to the improvement of a magnetic disk having a structure capable of being improved Recording properties when used in such a recording system.

In magnetic recording systems or installations that use a Using an elongated recording medium such as a magnetic recording tape, the recording medium usually consists Made of a flexible or elastic, non-magnetic base material on which a magnetizable coating is applied from very fine particles that are attached to the base by an elastic, solidifiable binder

are brought.

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Bank: Dresdner Bank AG, Wiesbaden. Account no. 276807

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The magnetizable particles are generally anisotropic, and it is known that one can make a good recording medium gets »when the anisotropic particles are aligned in the appropriate direction. As e.g. in the following US patent Sohriften No. 2 796 359 »3 021 230, 3 052 567 and 3 1i7 O65 described, the magnetic axes of the particles are best parallel to the direction of travel of the magnetic medium, of tapes or foils, aligned

The magnetic recording tapes or sheets are generally linear magnetic tapes, although other configurations can be used. such as strips or discs are known (see, for example, U.S. Patents 2,711,9OI, 3,046,836 and 3 047 429).

In the manufacture of linear magnetic tapes, the mass production technique commonly involves the manufacture of a very wide web of the tape is used, which is subsequently is cut into a number of narrow ribbons.

In the case of the mass production of magnetic disks, it is on the On the other hand, it has been customary to manufacture solid disks, which are produced individually by applying a magnetizable coating on "a disk made of a solid base material, such as metal," Such a process is slow and laborious and not even special for mass production suitable. .

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The technique used in mass production can, on the other hand, be applied to the production of elastic disks with physical ones Properties similar to those of ordinary linear belts can be adjusted. For example For example, the wide raw webs of the tapes that are currently being made for linear tapes can be sliced instead get cut. These wide raw webs for tapes, however, are with linearly oriented particles for reasons provided, which are described in the aforementioned patents. If thus magnetic disks from these raw webs would be punched out because of the magnetic particles the disks also aligned linearly. Such an alignment in a target system, however, led according to observations led to considerable disadvantages · When testing an elastic disc made from such a tape the incorrect alignment of the anisotropic particles relative to the transducer head in certain positions actually leads to a reduction in quality of the recorded signal · Thus, when the test disc rotated, it passed a transmitter the alignment of the particles on the disk relative to the transducer twice per revolution from parallel to transverse This resulted in extremely undesirable amplitude modulation, twice per revolution, with an obvious one Deterioration in terms of the design of the system *

It is therefore the object of the invention to provide an economical elastic magnetic disk for a magnetic disk recording

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system, which has a constant amplitude envelope Has; also to provide such a magnetic disk and a method for their production, which Provides uniform recording properties when rotating past an assigned pick-up head; furthermore the disk is economical and inexpensive to manufacture and is well suited for high speed, and also for continuous mass production in an uncomplicated manner and extremely practical way that is compatible with the existing production technology

In short, a preferred embodiment of this Invention a magnetic recording disc, which is made of an elastic, non-magnetic base material with magnetically anisotropic particles, which are consciously distributed essentially randomly aligned and thus from one elastic curable binder held on the base material will exist. By arranging the anisotropic particles in a substantially random pattern on the disk an alt one does not have preferred linear alignments with the The result is that when the disc rotates past a transducer, the properties of the recording disc are uniform are·

Further advantages, features and application examples of the present Invention emerge from the following description in conjunction with the drawings, in which:

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Fig. 1 is a schematic representation of a high speed production line for the production of the discs according to the invention,

Fig. 2 is a top plan view of the continuous web of Fig. 1 showing the randomly oriented magnetic particles and illustration of the punching of the disks from the track and

Fig. 3 is a side view of a magnetic disk recorder using the magnetic disk according to the invention

In a preferred embodiment, the magnetic disk 10 according to the invention also consists of an elastic, non-magnetic one Base 11 on which a plurality of magnetically anisotropic particles 15 are arranged. These particles are located are in a substantially arbitrary orientation, as can be seen in Fig. 2, and are on the base 11 by means of a generally elastic, curable binder 17 held * The particles 15 are preferably made of ferromagne ti shine Material and generally have the shape of needles

Fig. 1 shows a typical high speed process for the mass production of such randomly oriented magnetic discs. A continuous web of non-magnetic base material 11 is in a known manner on a Laying station 20 passed. Some stations are

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knows, and the magnetically anisotropic. Particle 15 »that then are mixed in a liquid binder or carrier 17 are evenly placed on the base 11 in this station. The web is allowed to go to a drying or drying chamber 21 continue, where the binder 17 solidifies · The web is now a wide, final one Magnetic tape 23, which is then continuously fed to a punching station 25. That is where the magnetic disks are 10 punched out of the final tape 23

If desired, the magnetic disks according to the invention With existing machinery, it is possible to do this simply by adding a punching station. The ready-made alignment magnet available typically for those Alignment of the linear bands is used, must be switched off Discs are produced in large numbers on existing facilities

Fig. 3 shows a non-aligned disc 10 according to the invention, as it is used in a Magnets ehe ibenauf ze recording system 30. The system 30 includes a transmitter 32, the outside on an arm 33 inwardly and which is driven by a drive means 35 is movable from the disc 10 is · The Soheibe 10 in turn, is rotated past a transformer 30 on a Ti · oh 3k · An amplifier 38 provides the necessary amplification of the system.

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Thus, the magnetic disks of the invention provide numerous advantages. They are thin and light and for shipping and stacking economical · you are elastic and therefore less likely to be torn or damaged on their recording surface, since they try to yield elastically to a shock »They are economical and easy to manufacture.

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Claims (2)

7304518 Claims Magnetic disk recording system with a magnetic Transmitter, an elastic disc with a magnetizable surface, a rotating device between the disc and Transmitter, with the help of which one can transfer the over-animal of a BaIm can follow over the magnetizable surface, with a Device with which the transformer is in operation the surface is brought, which is made up of a plurality of magnetically anisotropic particles in a solidifiable binder consists, characterized in that the magnetically anisotropic particles (15) with respect to the rotational movement of the disc (10) essentially have a random orientation in order to reduce the periodic attenuation of the and / or to keep recorded signals to a minimum regardless of the generally circular shape of the path. 2. Plant according to claim 1, characterized in that the particles (15) are a needle-shaped, ferromagnetic material and are randomly scattered in order to avoid parallelism of the longitudinal axes of the particles (15) . 3 · / Method of making an unaligned one , Magnetic disk for use in a magnetic disk recording eventc, /, ok characterized by the application of a plurality of maf-.notically aninotropic particles, which are in the essentially located in random alignment, on one 309832/1098 elastic, niohtmagnefcisch.es IHisismaterial, Itiuden der Particles attached to the base material in a substantially random manner Alignment and punching out of panes from the Dasisma material with the particles bound on it, k · A method according to claim 3, characterized in that the magnetically anisotropic particles of nadeIf (are intimately ferromagnetic η material and willküi'lich emus are scattered their Längsaohsen to avoid the parallel! and that the particles to the base material by a resilient, cured binder are bound " 309832/1098 Empty soap