Claims
- 1. A medium for storage of information through ablative writing by a laser that can be optically read comprising a solid substrate having a highly reflective soft metal layer adhered to at least one surface thereof, said soft metal layer comprising both a reflective and recording layer and being an alloy consisting essentially of about 25 to about 90 percent by weight tin, about 8 to about 60 percent by weight bismuth, and about 1 to about 25 percent by weight copper wherein said soft metal layer is in a sufficiently uniform, partially oxidized form to increase the C/N ratio and modulation depth of the layer after laser writing and said soft metal layer is substantially free of bismuth-rich dendrites.
- 2. The medium of claim 1 wherein the percentage of tin is from about 55 to about 80, the percentage of bismuth is from 20 to 35, and the percentage of copper is from 3 to 10.
- 3. The medium of claim 1 wherein said substrate is a flexible plastic tape.
- 4. The medium of claim 1 wherein said substrate is a plastic disc.
- 5. The medium of claim 1 wherein said substrate is a plastic card.
CROSS-REFERENCE TO RELATED APPLICATION
This is a division of application Ser. No. 07/906,906, filed Jun. 30, 1992, now U.S. Pat. No. 5,302,493.
US Referenced Citations (15)
Foreign Referenced Citations (1)
Number |
Date |
Country |
58-007394 |
Jan 1983 |
JPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
906906 |
Jun 1992 |
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