The strongest point about polyvinylidene chloride is its excellent barrier property (gas non-permeable property) against both oxygen and moisture, and its oxygen barrier property is maintained even at a high humidity. These are advantages that are not found with other resins. Taking advantage of such an excellent barrier property, polyvinylidene chloride has been used for a wide range of usual products, like packaging film for ham, sausage, cheese and other preserved food, as well as household-use cling wrap. It has also been used as a coating agent to provide a barrier property to paper or other types of plastic film. (See the coated film section of coating agents.)
Vinylidene chloride is first made from chlorine obtained by electrolysis of salt (sodium chloride) and ethylene obtained by pyrolysis of petroleum.
CH2=CH2（ethylene）＋ Cl2（chlorine） → CH2Cl-CH2Cl（1,2-dichloroethane）
CH2=CH2（ethylene）＋ 2HCl（hydrogen chloride）＋ 1/2O2（oxygen）
→ CH2Cl-CH2Cl（1,2-dichloroethane）＋ H2O（water）
CH2Cl-CH2Cl（1,2-dichloroethane）→ CH2=CHCl（vinyl chloride）＋ HCl（hydrogen chloride）
CH2=CHCl（vinyl chloride）＋ Cl2（chlorine）→ CH2Cl-CHCl2（1,1,2-trichloroethane）
CH2Cl-CHCl2（1,1,2-trichloroethane）＋ NaOH（sodium hydroxide） or Ca（OH)2（calcium hydroxide）
→ CH2=CCl2（vinylidene chloride）＋ NaCl（sodium chloride） or CaCl2（calcium chloride）
Vinylidene chloride products are produced in accordance with the European Union (EU), U.S. Food and Drug Administration (FDA) and other regulations on food packaging materials.
Under the Japanese Food Sanitation Act, general standards and standards for individual materials have been set for plastic utensils, containers and packages for food.
To supplement these standards, plastic-related industries are ensuring the safety of food packaging materials by setting voluntary standards for individual materials.
The voluntary standards of the Japan Hygienic Association of Vinylidene Chloride for polyvinylidene chloride consist of voluntary standard values, hygiene test methods and a positive list.
The positive list is a list of raw materials and additives that can be used for food packaging plastics based on safety assessment. In case of polyvinylidene chloride products, such substances are selected from those allowed by the latest food hygiene laws and regulations of Japan, the US and EU. Each member of Japan Hygienic Association of Vinylidene Chloride ensures the safety of polyvinylidene chloride food utensils/containers/packages in accordance with these voluntary standards.
For cling wrap for home use that is made from polyvinylidene chloride, softening and stabilizing agents are used as additives. Additives registered by the voluntary standards of the Japan Hygienic Association of Vinylidene Chloride and certified by the European Union (EU) or U.S. Food and Drug Administration (FDA) for food packaging plastics are used.
If oily, deep-fried or other cooked food that is in direct contact with cling wrap is microwaved, the heatproof temperature limit of the film may be exceeded and the film may break. In such a case, place food in a deep, heatproof container and cover it with cling wrap so that it is not in direct contact with food.