戊二醇 具有抑菌效果之多元醇，可帮助保湿及渗透，添加量在5%左右，就具有防腐效果，但对于产品开封后之保存无法与真正防腐剂相同。

A synthetic skin-replenishing agent and solvent.

Pentylene Glycol is synthetic humectant used in cosmetics and beauty products that is also secondarily used as a solvent and preservative. It is both water and oil-soluble and can have moisture-binding and antimicrobial properties


http://www.creative-developments.co.uk/papers/Preservatives%20SPC%202000.htm

戊二醇是用于化妆品和美容产品的合成保湿剂，其次也用作溶剂和防腐剂。它既可溶于水，也可溶于油，并具有结合水分和抗菌的特性。

PAULA'S CHOICE:
Also known as vitamin B3 and nicotinic acid, niacinamide is a very effective skin-restoring ingredient that offers multiple benefits for aging and blemish-prone skin. Among these benefits is the ability to visibly improve the appearance of enlarged pores, uneven skin tone, fine lines, dullness, and a weakened skin surface. Niacinamide can also mitigate and to some extent help visibly repair damage from UV light and offset other sources of environmental attack, including the negative impact of various types of airborne pollutants. Unlike many beneficial ingredients, niacinamide is stable in the presence of heat and light.

https://www.paulaschoice.com/ingredient-dictionary/skin-soothing/niacinamide.html?fdid=ingredient-dictionary&crefn1=name-first-letter&crefv1=N&csortb1=name&csortd1=1

Incorrect comment above^