Clear Adhesive Tape, Example E as Written: Rubber, Rosin and Beta-Naphthol in Benzol (Drew 1939)

Drew's clear tape made exactly to his Example E: 250 parts rubber, 160-200 parts rosin and 2.5 parts beta-naphthol, stirred into about 3,248 parts benzol with no milling, spread on a clear cellulose film and dried. The beta-naphthol is an antioxidant that gives the adhesive a longer life. Our earlier tape used naphtha and left the beta-naphthol out. Source: R. G. Drew (3M), US 2,177,627 (1939). Smoked sheet for the latex crepe and celluloid for the film are both his own allowances. Benzol is poisonous: fume hood and respirator. Picture: a roll of clear tape (BarberJP, Wikimedia Commons, public domain).