Thomas Sullivan, a tea merchant in New York, often sends samples of tea to potential customers. In order to reduce the cost, he came up with a way, that is, to put a little loose tea in several silk bags. At that time, some customers who didn't make tea, after receiving the silk bags, often threw them into the boiling water directly because they didn't know the procedure of making tea. But gradually, people found that such packaged tea is convenient and easy to use, and gradually formed the habit of using small bags to pack tea. Some people suggested to him that the silk bag was too fine, so he changed to cotton gauze for official commercial sale. In 1903, Sullivan applied for the patent of tea bag. By 1920, tea bag was widely used in American catering industry.
The original tea bag used silk bags, which cost a lot. Later, Boston businessman William Hermanson invented the paper fiber tea bag with heat resistance, which is closer to the modern tea bag in material. At the beginning, these American tea bags were all single bag shaped. Because of the simple form and the simple packaging machinery, the tea bags would be concentrated in the tea bags when they were put into the water, and the brewing speed was very slow. Later, someone put the tea into a W-shaped double bag, and found that it can speed up the brewing of tea in hot water. In 1949, the German teepack company produced the world's first fully automatic double bag tea bag packaging machine with this concept.
