| Records of the past |
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Records were not always made from PVC. Animals, vegetables and minerals have all been enlisted in the quest for the perfect reproduction.
The first records (from Berliner - see history of vinyl section) where made from a hard rubber known a vulcanite. Vulcanised rubber is produced by reacting rubber with sulphur or other agents to decrease its surface adhesion and to increase its strength.
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Early 78s were made out of shellac, a substance produced from the shells of Indian beetles. The insect Coccus lacca sucks sap from trees and then excretes the residue as a hard shell,
attaching itself to branches. The shells are harvested, then crushed and cleaned. Along with shellac, 78s would contain a filler (usually limestone) and carbon black as a colourant. Gum or resin was used as a binder. Some discs even contained rubbish such as old bottles and bits of masonry. Later the Edison Diamond disc was produced using wood flour, alcohol and phenol formaldehyde. |
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| dcressey@another.co.uk | copyright Daniel Cressey 2001 |