Physical and chemical sunscreens based on their actions can be seen as chemical absorbers and physical blockers.
Physical blockers contain minerals such as zinc oxide or titanium dioxide. They reflect or scatter the UV rays. They offer protection against both UVA and UVB rays. While chemical sunscreens allow the molecule to absorb high-energy ultraviolet rays and emit them out as lower-energy rays. This prevents ultraviolet rays from reaching the skin.
which one is better.
When applied correctly (at least a full ounce to all of the exposed areas of the body, reapplied every two hours or any time you’ve been swimming or sweating heavily) evidence shows physical and chemical blockers are both effective at preventing UV damage.
How do they work?
Physical sunscreens sit on top of the skin to block UV rays at the skin surface. But they may feel heavy leave a white cast on the skin and they rub off quite easily. However, these days sunscreens use nanotechnology to break down particles, making them more wearable.
Whereas Chemical sunscreens are thinner comparatively and, therefore, they are easier to apply on the skin.
It is important to wear sunscreen daily to prevent sun damage. Both physical and chemical sunblocks are effective in preventing UV damage. As long as you wear sunscreen and reapply. It every two hours, you are good to go.