Glossary

Occlusive Film

Written by Reviewed by the SYNC editorial team Published Last reviewed Editorial standards

Occlusive Film — a thin protective layer left on the skin surface by occlusive ingredients that slows the evaporation of water from the outer skin. By reducing transepidermal water loss, this film helps the skin retain moisture and supports a comfortable, protected barrier.

Key points

  • Common occlusive agents include petrolatum, mineral oil, beeswax, and certain silicones.
  • The film works mainly by physically limiting water loss rather than adding water to the skin.
  • Occlusives are often layered over humectants to help seal in the water those ingredients attract.
  • Petrolatum is frequently cited as one of the most effective single occlusive ingredients for reducing water loss.

Frequently asked

Do occlusives moisturize on their own?

They mainly prevent water from leaving the skin rather than supplying moisture, so they work best paired with water or humectant ingredients underneath.

Will an occlusive film clog pores?

Some heavier occlusives may feel greasy, but many, including petrolatum, are widely considered non-comedogenic, though individual responses can vary.

Related topics

This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.

Encyclopedia

Further reading

This entry was written and checked against the sources below. They are published by clinical and scientific bodies, they are listed most readable first, and each one opens in a new tab. They are background for the whole entry rather than footnotes to individual sentences.

  1. Emollients and Moisturizers (Moisturisers) DermNet NZ Clinical guidance dermnetnz.org
  2. Moisturizers StatPearls (NCBI Bookshelf) Reference text ncbi.nlm.nih.gov
  3. Moisturizers: The Slippery Road PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  4. Moisturizer in Patients with Inflammatory Skin Diseases PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  5. Role of topical emollients and moisturizers in the treatment of dry skin barrier disorders PubMed Peer-reviewed (abstract) pubmed.ncbi.nlm.nih.gov
  6. The Skin Barrier and Moisturization: Function, Disruption, and Mechanisms of Repair PubMed Peer-reviewed (abstract) pubmed.ncbi.nlm.nih.gov

SYNC does not publish medical advice. Nothing here replaces a consultation with a doctor or a pharmacist about your own skin.