mouth freshener; oral deodorant
A product that freshens the mouth or reduces oral odor, such as breath mints, sprays, or strips.
Using a mouth freshener after a meal leaves your mouth feeling refreshed.
口臭予防 refers to the prevention of bad breath in general, while 口中清涼剤 specifically denotes a product that freshens the mouth.
Compound of 口中 (mouth interior) + 清涼 (cool and refreshing) + 剤 (preparation, agent).