Characteristics of plastic luminous agent

The remarkable characteristics of metal sulfide system are rich luminescent colors, which can cover the luminescent region from blue to red; The disadvantage is that
Unstable chemical properties, low luminous intensity and short time.
The characteristics of rare earth aluminate luminous agents are as follows
① High luminous efficiency. Aluminate luminous agents have high quantum efficiency in visible light region, and are used in plastics.
The amount is small, which is beneficial to reducing the manufacturing cost of luminous plastics.
② Long luminous time. For sulfide system, the luminescence time is generally 3 ~ 5 hours. At present, aluminate luminous substances are
When Eu2+ is activated, its luminous brightness can reach the recognizable level of human eyes for more than 2000min.
③ The chemical properties are stable. Because of the special composition and structure of aluminate luminous agent, it can resist acid and alkali, radiation,
Strong oxidation resistance and ultraviolet resistance, long service life and good weather resistance, and can be used in air and some special environments for a long time. be the same
Because the chemical properties of these substances are stable, they also have the characteristics of high fluorescence quenching temperature.
④ There is no radioactive hazard. Because the luminous intensity of sulfide system should be improved by adding radioactive elements such as cobalt
And the aluminate luminous agent does not need to be added with such elements.
Therefore, this kind of luminous agent is very safe to human body and environment, and it is mainly used for plastic luminous agent at present. Table 5-7 shows aluminate.
Performance comparison between salt and sulfide plastic luminous agents.