https://bio.nikkeibp.co.jp/atcl/news/p1/24/03/15/11690/

Kao has commercialized an insect repellent in Thailand and Singapore using silicone oil. The cream-like formulation contains silicone oil and citronella oil. It is well received for its non-irritating and easy-to-like scent.In the regions where it was released, people have a lifestyle of using body lotion to moisturize after bathing, so by using Mos Block Serum, it has both moisturizing and insect repellent effects.

The basic finding is that on normal skin, mosquitoes stop and suck blood (left), but on skin coated with silicone oil (right), mosquitoes quickly leave and do not suck blood (photo provided by Kao). Mosquito feet are covered with scaly bumps and hydrophobic components that repel water. On top of hydrophobic solutions, their legs feel dragged and they sink. For this reason, mosquitoes instinctively avoid hydrophobic solutions, and when they come into contact with skin coated with hydrophobic silicone oil, they immediately move away.