Sunscreen absorbs into leather just as it does on your skin, sinking into the hide and leaving a greasy residue on top. But instead of protecting the leather from a nasty sunburn, it creates a dark stain that's impossible to clean up with towels. The trick is to soak up the outermost grease and leave an absorbent product over the stain for several hours to pull out even more oils. Remove any residual discoloration with a cleaner meant for leather.
Absorbing the Grease
Begin treating sunscreen stains in leather quickly to minimize how much of the product sinks in.
Blot the stain with a very soft, absorbent cloth, lifting as much of the mark as you can. Microfiber works well, but a cotton T-shirt makes a good alternative.
Fold a cloth over two or three fingers. Working from the edge of the mark in toward the center, very gently rub the surface of the stain with little-to-no pressure. You want to create a small amount of heat to soften the oils left behind in the leather without working the stain deeper into the material. Don't go outside of the stain line – it may cause the mark to spread.
Cover the mark liberally with corn starch, talcum powder, unscented baby powder or baking soda. The first two are best, followed closely by baby powder; baking soda works in a pinch, but it's not quite as absorbent. The stain needs to be completely covered and the leather totally hidden for this to work. Wait 24 hours before gently vacuuming up the residue.
Dissolving Soaked-in Marks
If you're left with just a small amount of discoloration, simply repeat the process once more to eliminate the stain. If the mark is still pretty noticeable, the sunscreen sunk deeper into the leather than the powder can pull out. At this point, you'll need to use a degreasing product, but the best option depends on the type of leather.
Nubuck and suede: Clean the area with an over-the-counter product meant specifically for suede or nubuck. These types of leathers should rarely be cleaned with water-based products; cleaners meant for both are typically solvent-based.
Smooth leather: Mix unscented, liquid hand soap or unscented baby soap with cool water in a small bowl until suds appear on the top of the water. Dip a soft rag in just the suds and gently work them into the mark. Fill a spray bottle with distilled water, spritz the area lightly and blot with a dry, clean cloth to rinse out the soap. Repeat until the mark disappears.
Re-Hydrating the Leather
The process used to remove sunscreen stains from leather is designed to eliminate the grease and oil left behind by the product; but in turn, it also removes some of the natural oils from the leather. When the leather is dry, apply a leather conditioning product or make your own. As with cleaners, always test the product in a hidden area.
Homemade Leather Cleaner
Mix 1 part white distilled vinegar with 2 parts boiled linseed oil, lemon essential oil or olive oil. Apply the mixture to the leather; let it sit for a few hours, and buff out the residue with a soft cloth. The oil re-hydrates the leather, while the vinegar dissolves any remaining soap residue.
If you didn't need to use soap, and the talcum powder or other absorbent product appears to have worked, apply a few drops of lemon essential oil to a soft cloth and work it into the leather to rehydrate it. Buff out any excess after a few hours.
Don't use conditioners on suede or nunbuck. Instead, brush it gently with a soft baby hair brush to fluff up the nap after it dries.