Early tea bags were mostly simple square single-bag shapes. When placed in water, the tea leaves concentrated inside, resulting in a slow brewing process. However, due to their simplicity and the relatively rudimentary packaging machinery, they remained the most commonly used type of tea bag.
With the rise in popularity of fruit and flower teas, ordinary tea bags, due to their small size, could not accommodate the expansion of fruit pieces and petals. Diamond tea bags began to appear on the market. As the name suggests, diamond tea bags resemble diamonds, with a tetrahedral structure and are packaged in food-grade nylon. These tea bags have a delicate and translucent appearance, and the large interior space facilitates the release of aroma and allows for observation of the tea leaves' shape changes, representing a future mainstream trend in tea bags. However, diamond tea bags are expensive to produce, and few factories can manufacture them. Therefore, they are mostly used in higher-end products. 7talks in China uses only diamond tea bags.
In recent years, functional combination tea bags have emerged, such as the 7-Day Health Herbal Tea Set. These products combine different herbal ingredients according to their health benefits on a weekly basis and are packaged in sealed small bags.
In addition, there are some uniquely shaped tea bags. These tea bags are based on diamond-shaped tea bags with some exaggerated modifications. Although they have a novel and interesting appearance, the manufacturing process is extremely complex, and few brands use them.
