VC essence can't be used when it turns yellow. Reasons for yellowing of vc essence: Vitamin C is highly reducible due to its ethylene glycol structure, which is easily destroyed by air oxidation during storage. Vc refers to vitamin C, also known as vitamin C, which is a polyhydroxy compound with the chemical formula of C6H8O6. The role of VC can focus on preventing ultraviolet damage, diluting melanin precipitation and promoting collagen growth.

Steps to use VC essence correctly: Step 1: Wash your face with mild facial cleanser. Step 2: After washing your face, spray a toner that suits you. Step 3: Drop a drop of vitamin C essence in the palm of your hand, gently massage around your eyes and other parts of your face, and slowly absorb it.

Step 4: Apply emulsion Step 5: Apply eye cream. Apply eye cream according to the spot coating method. Don't rub the skin around your eyes hard, it is easy to form wrinkles.

Step 6: Sun protection.