# US 5,707,754 A · Magnetic recording medium and thermal recording printing device adopting the same

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- Number: US 5,707,754 A
- Document ID: US5707754A
- Status: Granted
- Kind: A
- Application number: 08/587,540
- Filed: 1996-01-17
- Granted: 1998-01-13
- Earliest claimed: 1995-01-26
- Assignees: Sharp Kabushiki Kaisha
- Inventors: Kazuo Van; Hitoshi Isono
- Web page: https://patentgrep.com/patent/US5707754A

## CPC

- G11B 5/656: {containing Co (containing inorganic, non-oxide compounds of Si, N, P, B, H or C G11B5/657; containing oxygen G11B5/658)}
- Y10S 428/90: Magnetic feature
- Y10T 428/12465: having magnetic properties, or preformed fiber orientation coordinate with shape
- Y10T 428/12806: Refractory [Group IVB, VB, or VIB] metal-base component
- Y10T 428/12819: Group VB metal-base component
- Y10T 428/12861: Group VIII or IB metal-base component
- Y10T 428/24975: No layer or component greater than 5 mils thick
- Y10T 428/265: 1 mil or less
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A thermomagnetic printer of the in-plane magnetization system includes a magnetic recording layer made of Dy.sub.x Co.sub.(1-x) or Dy.sub.y Co.sub.(1-y) and a base layer made of Ti or Ta. Since the described arrangement enables the magnetic recording layer to be formed by the sputtering method or the electron beam evaporation method, and the like, the magnetic recording layer having a uniform thickness and properties in a large area can be formed without difficulties. In addition, by adopting the Ti layer or the Ta layer as the base layer, a reduction in a residual magnetization can be prevented even when the magnetic recording layer is made thicker, thereby increasing a magnetic attraction force.

## Claims

### Claim 1

A thermomagnetic printing device, comprising:
a magnetic recording medium for recording thereon a magnetic latent image made of an amorphous alloy thin film of a formula Dy.sub.x Co.sub.(1-x), wherein
0.11.ltoreq.x.ltoreq.0.14;
a base having said magnetic recording medium formed on a surface thereof; and
a base layer consisting of a Ta layer, formed between said base and said magnetic recording medium.

### Claim 2 (depends on 1)

The thermomagnetic printing device as set forth in claim 1, wherein:
said base layer has a film thickness in a range of 0.1 .mu.m and 1.0 .mu.m.

### Claim 3 (depends on 1)

The thermomagnetic printing device as set forth in claim 1 wherein:
said magnetic recording medium has a thickness in a range of from 0.5 .mu.m to 2 .mu.m.

### Claim 4

A thermomagnetic printing device, comprising:
a magnetic recording medium for recording thereon a magnetic latent image made of an amorphous alloy thin film of a formula Dy.sub.x Co.sub.(1-x), wherein
0.11.ltoreq.x.ltoreq.0.14;
a base having said magnetic recording medium formed on a surface thereof; and
a base layer consisting of a Ti layer, formed between said base and said magnetic recording medium.

### Claim 5 (depends on 4)

The thermomagnetic printing device as set forth in claim 4, wherein:
said base layer has a film thickness in a range of 0.1 .mu.m and 1.0 .mu.m.

### Claim 6 (depends on 4)

The thermomagnetic printing device as set forth in claim 4, wherein:
said magnetic recording medium has a thickness in a range of from 0.5 .mu.m to 2 .mu.m.

### Claim 7

A thermomagnetic printing device, comprising:
a magnetic recording medium for recording thereon a magnetic latent image made of an amorphous alloy thin film of a formula Tb.sub.y Co.sub.(1-y), wherein
0.09.ltoreq.y.ltoreq.0.13;
a base having said magnetic recording medium formed on a surface thereof; and
a base layer consisting of a Ta layer, formed between said base, and said magnetic recording medium.

### Claim 8 (depends on 7)

The thermomagnetic printing device as set forth in claim 7, wherein:
said base layer has a film thickness in a range of 0.1 .mu.m and 1.0 .mu.m.

### Claim 9 (depends on 7)

The thermomagnetic printing device as set forth in claim 7, wherein:
said magnetic recording medium has a thickness in a range of from 0.5 .mu.m to 2 .mu.m.

### Claim 10

A thermomagnetic printing device, comprising:
a magnetic recording medium for recording thereon a magnetic latent image made of an amorphous alloy thin film of a formula Tb.sub.y Co.sub.(1-y), wherein
0.09.ltoreq.y.ltoreq.0.13;
a base having said magnetic recording medium formed on a surface thereof; and
a base layer consisting of a Ti layer, formed between said base and said magnetic recording medium.

### Claim 11 (depends on 10)

The thermomagnetic printing device as set forth in claim 10, wherein:
said base layer has a film thickness in a range of 0.1 .mu.m and 1.0 .mu.m.

### Claim 12 (depends on 10)

The thermomagnetic printing device as set forth in claim 10, wherein:
said magnetic recording medium has a thickness in a range of from 0.5 .mu.m to 2 .mu.m.