功能？

化妝品防腐劑成分使用基準表
74年7月23日衛署藥字第539747號公告
Dehydroacetic acid and its salts 0.5%

CIR安全審查：CIR專家小組發現，含有這些成分的化妝品在許多臨床試驗中實際上無刺激性，不致敏性，不光敏性和無光毒性。
CIR專家小組指出，脫氫乙酸鈉和脫氫乙酸在低濃度(小於等於0.6％)對細菌和真菌均是有效的抗菌劑，並且脫氫乙酸的最適pH範圍為2至4。通過阻止微生物的生長而不是殺死微生物來採取行動。

https://cosmeticsinfo.org/ingredient/dehydroacetic-acid

【Dehydroacetic Acid】

Rating: GOOD
Categories: Preservative

Dehydroacetic acid is a synthetic preservative used in amounts of 0.6% or less where it’s proven to be safe and effective. Dehydroacetic acid is characterized as a white to cream crystalline powder. Sometimes its salt form (known as sodium dehydroacetate) is used, as it is more soluble in certain types of cosmetic formulas. Dehydroacetic acid is most effective on fungi.

https://www.paulaschoice.com/ingredient-dictionary/ingredient-dehydroacetic-acid.html