“Negative ion” is a marketing concept. At present, there are only “negative charges” and “anions” in the field of chemistry, and there is no concept of “negative ions”.
In fact, the negative ion generators used in products such as air purifiers and hair dryer just produce electrons. The electrons generated by the “negative ion generator” of the hair dryer will neutralize the positive charge of floating objects in the air, allowing the hair to stick to each other, and the hair will become soft and not frizzy.
However, the effects of “no damage to hair”, “producing a protective film to protect hair scales”, and “anti-oxidation” as advertised by businesses have no basis. At present, the electrons ejected by the negative ion hair dryer can only make the hair plumper, without other substantial effects.
Secondly, this function is not effective for all hair types, such as men with short hair or harder hair, there will be no significant difference between using it or not. For such users, choosing a higher-priced negative ion hair dryer is not necessary.