NISSIN has been making contributions with the leading-edge technologies to a wide range of industries, including shipping, ice making and refrigerating warehouse, building air-conditioners, and special air-conditioners.

1. What is a refrigerant?

　The refrigerant is a material that acts as a cooling medium, delivering heat from a lower-temperature section to a higher-temperature section in a freezing cycle. As with ammonia and CFCs, it is a liquid (gas) that changes its state in a cycle. The refrigerant changes from liquid to gas when a lower-temperature section absorbs heat. If this gas is compressed and the heat is dissipated to a higher-temperature section, it goes back to liquid. Thus, by changing the physical state, it absorbs or dissipates heat.

2. Types of refrigerant

　Before 1945, refrigerants used in freezing had been mainly natural refrigerants such as ammonia, methyl chloride, and CO₂. However, since the 1930 invention of CFC gas, which is a fluorocarbon refrigerant, in the U.S., CFC gas has rapidly spread. In recent years, however, it was pointed out that CFCs deplete the ozone layer and contribute to global warming. As a result, natural refrigerants have started to be widely used again. Freon is a generalized product name of fluorocarbon. It is a generic name of halogen refrigerants based on hydrocarbon. Depending on the composition, there are many types of Freon, which are largely classified into CFC, HCFC, and HFC. Each refrigerant has its specific name. Since chemical names are difficult to remember and easy to get confused, numbers are assigned to refrigerant types, and “R” of refrigerant is added to the head of the symbol to use as names.

(Naming scheme of refrigerant)

3. Basic characteristics of refrigerant

　Before 1945, refrigerants used in freezing had been mainly natural refrigerants such as ammonia, methyl chloride, and CO₂. However, since the 1930 invention of CFC gas, which is a fluorocarbon refrigerant, in the U.S., CFC gas has rapidly spread. In recent years, however, it was pointed out that CFCs deplete the ozone layer and contribute to global warming. As a result, natural refrigerants have started to be widely used again. Freon is a generalized product name of fluorocarbon. It is a generic name of halogen refrigerants based on hydrocarbon. Depending on the composition, there are many types of Freon, which are largely classified into CFC, HCFC, and HFC. Each refrigerant has its specific name. Since chemical names are difficult to remember and easy to get confused, numbers are assigned to refrigerant types, and “R” of refrigerant is added to the head of the symbol to use as names.