Japan manages food contact materials using a "positive list" system, which involves listing all chemicals recognized and allowed for use in food contact applications. The positive list is applicable to synthetic resins and does not extend to materials beyond synthetic resins. It targets substances that are released from utensils, containers, and packaging into food, substances applied to the surfaces of these items for antistatic or anti-fog purposes, substances produced by chemical changes in the raw materials, and substances such as catalysts and additives that support polymerization reactions but are not expected to remain in the final product. In the Japanese Positive List for Food Contact Materials - Additives, additives are defined as organic low-molecular-weight substances with a molecular weight under 1000, intended to alter the physical or chemical properties of the base material and remain in the final product without undergoing a chemical reaction. This includes substances with specific functional groups that exhibit particular effects on the base material and have a molecular weight over 1000. Substances with a molecular weight over 1000 that are liquid at room temperature and pressure, or those with specific functional groups that play a characteristic role in the base material, are also listed as additives. The Japanese Positive List for Food Contact Materials - Additives permits additives numbered 1 to 827. The list specifies the serial number, substance name, allowed amounts in five different material categories, and special provisions for each permitted additive.