It is not recommended to use eye black after it has expired. Here's why:
Reduced Efficacy: Over time, the pigments, binders, and other ingredients in eye black may undergo chemical changes after the expiration date. This can lead to a decrease in pigmentation, making it difficult to achieve the desired coloring effect, and the eye black may not show up as intensely or evenly on the skin as it should.
Increased Risk of Infection: The preservatives in eye black that prevent the growth of bacteria, fungi, and other microorganisms may lose their effectiveness after the expiration date. Using expired eye black increases the risk of introducing harmful microorganisms to the delicate skin around the eyes, which can cause eye infections, such as conjunctivitis, blepharitis, and other eye problems. Symptoms may include redness, itching, swelling, pain, and increased tearing.
Skin Irritation: The chemical stability of the ingredients in expired eye black may change, which can increase the likelihood of skin irritation and allergic reactions. The skin around the eyes is very thin and sensitive, and using expired products can cause adverse reactions such as rashes, redness, and burning sensations.
