Waxed paper cup:
In 1932, the first waxed two-piece paper cup came out, and its smooth surface could be printed with a variety of exquisite patterns to improve the promotional effect. Paper cup wax, on the one hand can avoid the beverage and paper direct contact, and can protect the adhesive adhesion, enhance the durability of the paper cup; On the other hand, the thickness of the side wall is also increased, so that the strength of the paper cup is greatly improved, thus reducing the amount of paper necessary for the manufacture of stronger paper cups and reducing the production cost.
As waxed paper cups became containers for cold drinks, people also wanted to use a convenient container to hold hot drinks. However, the hot drink will melt the wax layer on the inner surface of the paper cup, and the adhesive mouth will be separated, so the general waxed paper cup is not suitable for holding hot drinks.

Straight wall double cup:
In order to expand the scope of application of paper cups, in 1940, straight wall double-layer paper cups were introduced to the market. This paper cup is not only easy to carry, but also can be used to hold hot drinks. Later, manufacturers coated these cups with latex to cover the "cardboard smell" of the paper and strengthen the leak-proof properties of the paper cups. Latex-coated single-layer waxed cups are widely used in self-service vending machines to hold hot coffee.

Coated plastic paper cup:
Some food companies are beginning to apply polyethylene to cardboard to increase the barrier and tightness of paper packaging. Because the melting point of polyethylene is much higher than that of wax, the new beverage paper cup coated with this material can be ideally used to hold hot beverages, which solves the problem that the product quality is affected by the melting of the coating material. At the same time, the polyethylene coating is smoother than the original wax coating, improving the appearance of the paper cup. In addition, the processing technology is also cheaper and faster than the latex coating method.