The rubber works' materials: Koylon, the fuel cells, and claims that belong to the parent

1929–1962 · MANUFACTURE IN MISHAWAKA, INVENTION ELSEWHERE — PRINTED AS SUCH

The tested claims: The Ball Band works made famous materials for sixty years, and local telling sometimes lets the making blur into inventing. This entry separates them, because the record does. Foam rubber — the material the plant sold as Koylon from 1937, on the marker's dating — was invented in 1929 at Dunlop Rubber in Birmingham, England, by E. A. Murphy and Eric Owen, who whipped liquid latex into a froth and vulcanized it; Dunlopillo was its first name, and Murphy's patent file runs to more than forty grants. The United States Rubber Company, Ball Band's parent from 1922, ran its own expanded-rubber program under its own patents — the trade record shows the company producing chemically expanded rubber from 1937 through about 1950 — and Mishawaka's documented share in Koylon is the share the marker gives: manufacture, at scale, in the plant on the river. No patent or trade account reached for this section places the invention of foam rubber, or of the parent's Ensolite foam or Royalite sheet lines (Royalite research and development began in 1962, on the marker's account, without a Mishawaka attribution), in this city, and the entry refuses to promote the plant into their inventor. The fuel cells stand differently, and at their true and considerable strength. Self-sealing fuel tanks were an industry-wide wartime art, developed inside the great rubber companies' laboratories; what Mishawaka did, documented in the city's own marker record and carried whole in the Ball Band file, was engineering under deadline of the first order: in February 1942 the plant's employees designed and built, around the clock and without being told why, three fuel tanks for each of the Army's B-25 bombers — a 225-gallon bulletproof cell for the bomb bay, a 160-gallon bladder for the crawlway, a 60-gallon tank for the lower turret — extending the bombers' range to some 2,400 miles for the Doolittle raid of 18 April 1942. That is design-and-build work of a high order, done in Mishawaka by Mishawaka people, and it is printed at exactly that strength: a documented engineering achievement, not a patented invention, and none the smaller for the distinction.

Sources:

1. The foam-rubber record (the Dunlop history and the E. A. Murphy literature) — latex foam first made in 1929 by E. A. Murphy and Eric Owen at Dunlop Rubber, Birmingham; Murphy's forty-plus patents; Dunlopillo as the first marketed form.
2. "Expanding Rubber Through the Years" (the rubber trade's technical history) — the United States Rubber Company's own expanded-rubber patent and its chemically expanded rubber production from 1937 to about 1950, a parent-company program.
3. Ball-Band Factory marker, as carried in the Ball Band file — Koylon foam from 1937 at the Mishawaka plant; Ensolite; Royalite research and development from 1962; the product-line datings printed without a Mishawaka invention attribution.
4. City of Mishawaka, historic markers account of the Doolittle Raid tanks, as carried in the Ball Band file — the February 1942 design and construction, the three tanks and their capacities, the 2,400-mile range, Doolittle's visit during production and his telegram after the raid.