From: Patent Tactics, George Brock-Nannestad

Hello, List Members,

just because a record is lightweight and not shellac, it is not necessarily 
vinyl. Vinyl, or rather polyvinyl chloride, is only one component with 
designable properties that may be used. Through the 1930s and with greater 
intensity during WW2 cellulose acetate compounds were increasingly used with 
other components as a shellac substitute. India was not a reliable source 
when the U-boats reigned. Shellac is only the binding component in shellac 
discs - the heavy and durable stuff is slate dust. And do not forget the 
carbon black - the records would look like concrete without it. So without a 
proper chemical analysis of the records discussed in the present thread as 
"vinyl", it is difficult to say what they are.

As long as records were pressed, the plastic of choice from the early 1950s 
had a large polyvinyl chloride content, but when injection molding of singles 
started in the 1960s, even polystyrene components were used.

Kind regards,


Richard Warren wrote:

> Dear Mike and List Readers,
> As you've probably found, some manufacturers released vinyl 78's without
> notice or with minimal notice. I've seen Columbia 78's pressed in black vinyl
> with very little if any indication of that fact; and several small labels used
> vinyl, usually either black or red, most or all of the time. Many children's
> records were pressed in vinyl, perhaps in order to use colored discs, probably
> also because of shatter-resistance. Many promos for radio station use were
> pressed in vinyl, while their marketed versions were made of shellac. Most
> vinyl 78's seem to have been marketed after WW II (but there are probably
> exceptions to that observation).
> Richard
> At 09:39 AM 9/22/2005, you wrote:
> >In a message dated 9/21/2005 1:30:21 PM Eastern Daylight Time,
> >[log in to unmask] writes:
> >It is worth noting that very few "78's" were ever pressed from vinyl.
> >***************
> >
> >At one time I thought the RCA Victor "Red Seal Deluxe" series was unique but
> >since I've found that several manufacturers released vinyl 78 consumer
> >series.
> >
> >It would be interesting to research how the use of vinyl for 78s meshed with
> >the manufacture of lightweight consumer record players that could play them
> >without damage and why anyone would buy them when they could get 45s or lps.
> >
> >Mike Csontos