Silver acts as a catalyst to produce two important chemicals: ethylene oxide and formaldehyde. Ethylene oxide is used to produce molded plastics, such as plastic handles, and flexible plastics, such as polyester. It is also a major ingredient in antifreeze. Formaldehyde is used to make solid plastics and resins and as a protective coating. It is also used as a disinfectant and embalming agent. As a catalyst, silver increases the speed of reactions without getting used up.