SU932545A1 - Magnetic record carrier sensitive layer - Google Patents

Description

The invention relates to instrumentation, in particular, to a working layer of a magnetic recording carrier, which can be applied mainly on a polyethylene terephthalate substrate. A working carrier layer of a recording medium containing a magnetic powder, made on the basis of needle-like particles of iron oxide, is known. The technology of such carriers is sufficiently developed, but at the present stage of development of information recording techniques these carriers are of low sensitivity, especially in the field of short-wave acoustic signals that are magnetic. records The closest to the proposed should be considered a working magnetic recording carrier layer containing magnetic powder made from chromium dioxide, the particles of which are evenly distributed in the composition consisting of phosphoric acid dialkyl ester, stearic acid butyl ester, partially saponified vinyl chloride copolymer with vinyl acetate, reactive polyurethane elastomer and hexametoxymethylmelamine 2. However, even this working layer, despite a number of its positive qualities, does not have a sufficiently good electric shock ical and physical-mechanical parameters. The purpose of the invention is to improve the electroacoustic and physico-mechanical parameters of the working layer of the magnetic recording carrier. This goal is achieved by the fact that in the working layer of a magnetic recording medium containing magnetic powder from chromium dioxide, the particles of which are evenly distributed in the composition consisting of dialkyl ether (Bosoric acid, butyl E (Lira of stearic acid, partially saponified vinyl chloride copolymer with vinyl acetate , 3 reactive polyurethane elastomer and hexamethoxymethylmelamine, particles of magnetic powder are oriented in the longitudinal direction with a coercive force from 480 to 510 Oe with the following ratio of components t AVA, DG: Dialkyl ester of phosphoric acid Butyl ester of stearic acid, 6-1, lots Partially saponified copolymer of vinyl chloride with vinyl 6-12 nylacetate Reactive polyurethane 6-12 elastomer Hexamethoxymethyl, 5-3, melamine Magnetic powder Oxide of chromium dioxide Realized It can be explained by three examples, the first of which is a working layer with a minimal amount of magnetic pores to the second - with an average amount and to the third - with the maximum quality of this chromium dioxide powder. Example 1. In a ball with a volume of 100 l, load: kg I Magnetic poro. shock from chromium dioxide Dialkyl phosphate ester Partially saponified vinyl chloride copolymer with vinylace 1, 7 11, tatom Reactive capacity polyurethane elastomer Hexamethoxymelamine Butyl ester of stearic acid 0.125 0, acid After a preliminary transfer of all the components to a volume of 8.8 kg of the flyer, which is used by the charts, will be applied to 8.8 kg. t dispersible composition, which is a nitrile varnish, in a bead mill. The lacquer is filtered, followed by an example of a curing catalyst, dodecylbenzene sulfoxide in an amount of two grams per two programs of lacquer), and the lacquer is applied to the ovum to obtain a working layer of magnetic recording. In irrigation, the orientation of the particles of the magnetically powder in the longitudinal direction is deteriorated. The curing of the working layer proceeds for two minutes at a temperature of 120 to. Example 2. All physical and physical processes are similar: 1. The composition is as follows: Chromium magnetic powder Dialkyl ether phosphorus 0, 3 2.4 hydrochloric acid Partially saponified vinyl chloride copolymer with vinyl acetate, 2 9.5 tom Reactive polyurethane elastomer Hexamethoxymethylmelamine Butyl ester of stearic acid, 1 0.8 noTiii Stirring is performed in the presence of 5.2 kg of cyclahexanone and 15 kg of lorethane. Example 3. All physical and physical processes are similar to priu 1. The composition has the following form: Magnetic powder from chromium dioxide. Dialkyl phosphate ester. Partially saponified vinyl chloride copolymer with vinyl, 8,6.8 acetate.

6.8

0.8 0.16 1.3 0, 0 0.3

Stirring is carried out in the presence of 3.5 kg of cyclohexanone and AND kg of dichloroethane.

The tests of the working layers obtained in the three examples are given in the table.

This table clearly shows that the proposed working layer allows video and phonograms to be performed with relatively low noises and with increased sensitivity, which increases the overall confidence level of the recorded and reproduced information I.

Surface electrical resistivity, Ohm / cm

Relative value of the recording current in the video signal channel (dB)

Relative returns in the video channel (dB)

Relative average sensitivity in the sound channel (dB)

Relative frequency response in the audio channel (dB)

Relative noise level of magnetized magnetic tape (dB)

Claims (2)

Invention Formula The working layer magnetic record carrier, comprising magnithy powdergramm of chromium dioxide particles which are uniformly distributed in the composition, consisting of a dialkyl ester of phosphoric acid, butyl ester of stearic acid, a partially saponified copolymer of vinyl chloride with vinyl acetate, reactive gyuliuretanovogo elastomer and hexamethoxymethylmelamine about Whitlock and h 8, 1-10 1,2-10 Over 30 more than 30 0.0 0.0 O. 2.0 0.0 0.1 1.0 1.0 kQ kk So that, in order to improve its electroacoustic and physico-mechanical parameters, the particles of the magnetic powder are oriented in the longitudinal direction with a coercive force from d80 to 510 Oe with the following ratio of composition components, wt.%: Phosphoric acid dialkyl ester Stearic acid butyl ester0,6-1.0 Partially saponified vinyl chloride / vinyl acetate copolymer Polyurethane elastomer Hexamethoxymethyl. Melamine  ,eight I Magnetic powder chromium dioxide Else Sources of information taken into account in the examination 5 l. Braginsky G.I. and other technologies of magnetic tapes. L., Himi, EM, p. 163. 2. USSR author's certificate No. 587 95, cl. G 11 V 5 / 68,1977 (prototype).