Technically named Polyacrylic Acid, Carbomer is a synthetic high-molecular weight polymers of acrylic acid. They help to distribute or suspend an insoluble solid in a liquid.  It also is an emulsifying agent, keeping oil and water together.

Can be found in the following O Naturals Products: Nourishing Watermelon & Vitamin C Gel Face Mask, Anti-Aging Kiwi & Vitamin E Gel Face Mask, Antioxidant Lemon & Vitamin B Face Mask, Brightening Coffee & Vitamin A Gel Face Mask