DD161177A3 - METHOD AND DEVICE FOR PRODUCING MAGNETOGRAPHY CARRIER - Google Patents

Abstract

Process for the production of magnet program carriers with smoothed magnetic layer, which contains magnetizable particles to be oriented in a magnetic field, characterized in that a dispersion (3) containing a base, containing magnetisable particles is smoothed in the magnetic field.

Description

For this 1 page drawings

The invention relates to a method and an apparatus for producing magnetogram carriers with a smoothed magnetic layer which contains magnetizable particles to be oriented in a magnetic field.

In the production of Magnetogrammträgern is a magnetic layer in the form of a liquid dispersion of binders, solvents, magnetizable mostly acicular particles and optionally on a non-magnetic pad

other additives. ,.

In practice, for example, in the production of tape-shaped Magnetogrammträger the Gravierwalzverfahren has proven to be advantageous. The dispersion is transferred by means of an engraved roller to the substrate and then smoothed. The smoothing can be magnetic or mechanical, the latter method has proved to be particularly advantageous because it is largely independent of the rheological properties of the dispersion. Thereafter, the magnetizable particles are oriented in the still liquid magnetic layer prior to solidification in a known manner. This is achieved, for example, by placing the coated base between two of the same polarity

Magnet or other magnetizing devices are used. ,

However, the disadvantage here is that the previous smoothing of the surface of the magnetic layer is again disturbed by the orientation of the magnetic particles. On the other hand, the orientation of the magnetic particles is disturbed when the smoothing of the magnetic layer is performed after the orientation. Both methods deteriorate the electromagnetic properties of the magnetogram carrier. The signal-to-noise ratio and the possibility of reproducing small wavelengths become smaller as well as the level density of the magnetogram carrier

limited.

The purpose of the invention is to produce magnetogram carriers with higher achievable storage densities.

The invention has for its object to simultaneously perform the orientation and smoothing of the magnetic layer.

According to the invention, magnetogram carriers with a smoothed magnetic layer containing magnetizable particles to be oriented in a magnetic field are produced by smoothing a substrate-covering dispersion which contains magnetizable particles in the magnetic field. As a result, a simultaneous orientation and smoothing of the magnetic layer is achieved.

The device for carrying out the method according to the invention consists of a magnet arrangement, between whose poles one or more smoothing bodies are attached. The magnet arrangement is located underneath and / or above a support passed by. This is covered with a dispersion containing magnetizable particles. By this arrangement of the parts of the device is achieved that the once treated structure of the magnetic layer after leaving the

Device does not change anymore. , .. '

The smoothing body consists of a magnetic field lines substantially not influencing material. As a result, the course of the field lines and thus the orientation direction is not disturbed.

The smoothing body may be fixed or pivotally mounted as a thin roll.

The solution according to the invention prevents an influence on the already smoothed magnetic layer as a result of the orientation of the magnetizable particles, as is the case with separate smoothing and magnet arrangements. The smoother and denser magnetic layer increases the possibility of reproducing small wavelengths and increases the signal-to-noise ratio

and the level-equilibrium is increased. This allows higher storage densities to be achieved. ,

The invention will be explained below using an exemplary embodiment.

In the accompanying drawing show

1 shows a system for smoothing the dispersion in the magnetic field which orientates the magnetizable particles, FIG. 2 shows a system corresponding to FIG. 1 with a different magnet arrangement and another smoothing body,

Fig. 3: serving as a smoothing body pivotally mounted \ Na \ ze. ;

The strip 3 applied by means of the known engraving roller method onto the moving base 2 in the form of a strip is transported past the poles 5 of the magnet arrangement 4. In the magnetic field of the magnet assembly 4, the particles are magnetized in the dispersion 3 and thus oriented in the field line direction. Simultaneously with the orientation, the dispersion 3 is smoothed by the smoothing body 6, so that a Magrietogrammträger with smoothed magnetic layer and oriented magnetizable particles leaves the system.

Claims (4)

-1- 167 224 Invention claims:. Ί. Process for the preparation of magnetic-layer magnetograms with a smoothed magnetic layer containing magnetizable particles to be oriented in a magnetic field, characterized in that a substrate-covering dispersion (3) containing magnetisable particles is smoothed in the magnetic field. 2. Apparatus for carrying out the method, characterized in that under and / or over a magnetisable with a particle containing particles contained dispersion (3) covered underlay (2) a magnet assembly (4) is mounted and between the poles (5) of the magnet assembly ( 4) one or more smoothing bodies (6) are arranged. 3. Apparatus for carrying out the method according to claim 2, characterized in that the smoothing body (6) consists of a magnetic field lines substantially not influencing material. 4. An apparatus for carrying out the method according to Anspruchs, characterized in / that the smoothing body (6) fixedly mounted or mounted as a thin roller is pivotally mounted.