At the time when Sullivan popularized the GREEN TEA 9371 bag, many tea bag producers began experimenting with different materials for his tea bags, such as cheesecloth, gauze, cellophane and perforated paper. Paper fiber won out as the preferred tea bag material of the day. Hand-sewn bags were replaced by machine-sewn ones. Later, William Hermanson (one of the founders of Technical Papers Corporation of Boston) invented heat-sealed paper tea bags and sold his patent to the Salada Tea Company in 1930.
