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Grease stains can be left on a leather sofa from hair, beauty products, or food. It is best to try to remove these stains as soon as you notice them. Wipe the surface of the leather with a leather cleaning solution and then dry the leather thoroughly. If the stain remains, try sprinkling baking soda or cornstarch on the stain. Let the powder sit there for several hours and then brush away the residue. Carefully blot the ink stain with a cotton ball dipped in rubbing alcohol. Use care and do not soak the leather. Once the stain is lifted, clean the surface of the leather with a damp rag and dry the area thoroughly with a clean rag. Mix equal parts lemon and cream of tartar as a stain treatment. Apply the mixture to the stain and let it sit for 10 minutes. Use a damp cloth to remove the mixture, then dry it with a clean cloth.You can repeat the treatment again as needed.

Summary:
Remove grease stains. Get rid of ink stains. Treat dark stains on light-colored leather.