Vinyl Wins Again

Excerpts from The Care and Handling of Recorded Sound Materials


Vinyl discs

Vinyl discs are adversely affected by ultraviolet light and thermal cycling (heat fluctuation). The consequence of thermal cycling is that each cycle of temperature results in a small irreversible deformation, and these deformations are cumulative. Vinyl discs are resistant to fungal growth and are unaffected by high humidity levels.

CDs

The compact disc is a laminate of 4 different materials. The bottom of the disc is made of polycarbonate onto which the pits containing the digitized sound information are stamped. A thin layer of aluminum is then applied, covering the pits. A thin lacquer coating (which becomes the top of the disc) is then applied to cover the aluminum layer, and finally the ink for the labeling.

As with any laminated products, one must wonder how the aging characteristics of each material will interact with, and affect adjacent layers.

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Thus far, vinyl has proven to be the most stable of the materials that have been used in the manufacture of sound recordings. However, although stable, its life is not indefinite. Pickett and Lemcoe, in Preservation and Storage of Sound Recordings, states that "failure by chemical degradation of a vinyl disc in ordinary library environments should not occur in less than a century".

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by Gilles St‑Laurent - Music Division - National Library Of Canada