A classic leather jacket is a wardrobe staple that may never go out of style. Just wearing your jacket outdoors on a rainy day can be a risk, however, because water can do real damage to the leather. If you want your leather investment to hold up for years, waterproofing is a good idea -- as long as you know the right way to do it.
Water can damage your leather jacket by forming temporary bonds with the leather's natural oils if it's allowed to sit on the material. Those natural oils are what lubricate the leather fibers, giving it its soft, supple feel and smooth appearance. They also help make the material more durable. When water bonds with the oils, it weakens the protein bonds that hold the fibers together, so they're more likely to break. As a result, your leather jacket can become stiff and dry. Water can also leave spots and streaks on the leather, and these watermarks are extremely difficult to remove once they occur.
Silicone Repels Water
Silicone sprays form a barrier over the surface of your jacket, so water beads up and is repelled before it can soak into the leather. An oil-based silicone spray works well on most smooth, full-grain types of leather. For a jacket made of napped leather, such as nubuck or suede, choose a lightweight water-based silicone spray. Because these leathers are more porous, they can soak up the heavier oil-based sprays and become discolored. Silicone waterproofing sprays can make your jacket feel a little slippery, and over time they may have a drying effect on the leather, so don't use them too often.
Acrylic Copolymer and Waterproofing
Acrylic copolymer sprays utilize newer technology to make leather waterproof. The acrylic copolymers in the spray create a net-like barrier that is too fine for water molecules to pass through, but still porous enough to allow your leather jacket to breathe. Unlike silicone sprays, acrylic copolymer sprays won't leave your jacket slippery either, and you don't have to worry about discoloration. They work for all types of leather.
Tips for Waterproofing
Always clean your jacket before using a waterproofing product. Wipe the leather with a soft cloth; keep the cloth dry so your jacket isn't wet before you begin the waterproofing process. When it's time to apply the spray, place your jacket on a hanger and hang it in a spot where you can easily reach all sides. Hold the can of waterproofing spray approximately 1 foot away from the jacket and spray evenly across the entire surface. Be sure to work in a well-ventilated area to avoid inhaling the spray. Allow your jacket to dry completely before you wear it. Because some waterproofing sprays can discolor leather, always test your product in an inconspicuous spot to see whether there is any reaction before spraying the entire jacket.