Reflective film is a retroreflective material that has been made into a thin film and can be used directly, and it is also the most widely used retroreflective material. [1] In 1937, the world's first reflective film was born in a laboratory in the United States. It is the starting point of the history of large-scale application of reflective film for traffic signs. In 1939, a sign made of reflective film was used for the first time in the open air on the highway side of Minnesota, USA. Since then, a new era in which a series of reflective products are used for traffic signs has been unveiled, creating a brand new The traffic safety industry. This year, the National Standard for Traffic Signs in the United States (Manual of United Traffic Control Devices, 1939, 1939 edition of the United States) officially stipulated that reflective films should be used to make traffic signs. [3]
Since then, with the development of the chemical industry, especially synthetic resins, various research and development institutions have continued to research and innovate, using glass bead technology, synthetic resin technology, thin film technology and coating technology to successively develop a series of high-quality retroreflective products.
Beginning in the 1940s, this initially manufactured reflective film was dubbed "engineering-grade" reflective film, and it was widely used in road traffic signs. [4] Since then, a series of products such as reflective films used in personal safety protection fields such as clothing have also been developed with the advent of synthetic resins and the needs of social development. Since then, with a series of research results in material technology and optical technology, especially the appearance of micro-prism reflective materials, this kind of reflective materials, which were originally mainly used for traffic signs, began to be gradually replaced by newer and better reflective materials.