Alcohol form of the B vitamin pantothenic acid. Panthenol is used in skincare products as a humectant because of its ability to attract and hold moisture.
Sometimes called pro-vitamin B5, panthenol mixes readily with many different types of ingredients, making it a versatile ingredient to be used in formulas because it improves the look and feel of skin.
References for this information:
The Journal of Dermatological Treatment, August 2016, pages 1-7; and December 2002, pages 173-178
Journal of Cosmetic Science, July-August 2011, issue 4, pages 361-370
American Journal of Clinical Dermatology, Volume 3, 2002, pages 427-433