Audio Systems: Picture Discs, poly vinyl chloride, continuous groove

Question
How are vinyl picture discs made?

Answer
The most simplistic definition of a picture disc is the incorporation of graphics and music onto a round or shaped disc. A more complete description of a picture disc record (modern day) or commonly referred to as a pic-disc, is a record containing a base layer of PVC (poly vinyl chloride), surrounded on both sides with a photographic layer, and finished up with a clear layer of PVC, again on both sides of the disc.

As the five layers are combined, a continuous groove of music is pressed into the playing surface. Any excess vinyl is then trimmed from the surrounding area giving the recording a clean edge and thereby completing the disc. Although pleasing to the eye, the overall sound quality of these recordings are not comparable to the better sounding black vinyl discs. This is due in part to ultra thin outside layers of clear vinyl which supports the grooves.

The origin of the picture disc or record dates back to the early 1920s. One of the first companies to develop these discs was the Musika Postkarte Co. of Germany. Other companies involved with this process were Trusound of Great Britain, Sav-Way Industries and the RCA Victor Corporation, both of the U.S.

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