I also have a set of "Townsend Clarke" 3 bias size 5 Vitalite bowls and was intrigued by manufacturer label and material, so with some difficultly, I researched and found the following information-
Originally Posted by The Basset
" In Ludwigshafen in Germany, the large Chemical Co,. RASHIG GmbH began producing a billiard ball with a phenol formaldehyde base – this was a “Resin Casting” – each ball being separately cast in glass mould – cured and then extracted by breaking the mould off the ball rather like shelling a hard boiled egg! The ball is then turned and finished on a centraless grinder and finally polished in the same manner as the original Bonzoline and Crystalate Balls. This Cast Resin Ball was slightly lighter in weight having a density of 1.7 as compared to the density of the original ball of 1.87, but it had beautiful bright colours and very attractive appearance.
The work of developing this new type of Cast Resin Ball was a closely guarded secret, carried out by a brilliant German Chemist named Doctor Koebner. In 1937 Mr. Darryl Warnford-Davis of the Composition Billiard Ball Supply Co, who was advised by Mr. Ronald Kinnear (grandson of the original Peter Kinnear) that Doctor Koebner, who was a Jew – was in England and wanted to stay here to escape from Hitlers Germany and the persecution of the Jewish People. With some considerable difficulty, in view of the pre-war situation, permission for him to stay and work with the Composition Billiard Ball Supply Co. Ltd, was obtained, and he worked with the Company until his death in 1949, producing a similar ball marketed under the name “Vitalite”.In return for the information about Doctor Koebner’s presence in London, it was agreed to share the knowledge of how to manufacture the Cast Resin Ball with the Albany Ball Co, - this promise was kept, and so this type of ball is now also made by Albany in USA.
Since the end of World War II the same type of ball has also been made in Belgium and marketed under the name of “Aramith”. As the materials for the original Cellulose Nitrate based ball became more difficult to obtain, experimental work on the Cast Resin Ball now produced the modern “Super Crystalate” Balls, with their bright attractive colours and a specific gravity almost equal to the old Crystalate. At the same time the Belgium Ball Manufacturers had improved their product to achieve the required density, which is now being marketed in the United Kingdom as the “Tournament Champion” Ball. Both these modern Cast Resin Balls are made to extremely close tolerances for both sizes and specific gravity."
So the development of the material it appears was due originally to the search for a replacement for ivory and celluloid based billiard balls.
The bias seems to be close to a "classic" to me, so although a smooth bowl they do have a wide bias for indoor, so are better suited for outdoor. My bowls are stamped '67! so have only been used when playing socially, but they are accurate . On name, you will find croquet sets still carrying the name of Townshend, this, I continue to research.