Zipper lubricant is a product that is used to help extend the life of a zipper and prevent it from rusting or getting stuck. Most commercially available zipper lubricants are made for use on both metal and plastic zippers, while there are also a few household items that may also help to lubricate a zipper.
Zipper lubricant also helps to clean out dust and debris from in between the zipper's teeth, which is why its use is recommended after the zipper is exposed to wet or dirty environments. Still, before using the lubricant, its suggested to first open the zipper, and then clean in between the teeth with a stiff brush.
Next, take a rag or paper towel, and put it behind the zipper so that no excess lubricant can come into contact with the rest of the garment. Then, apply the lubricant to both sides of the zipper, making sure to wipe off the excess before opening and closing the zipper a few times to thoroughly spread out the lubricant.
If there is no zipper lubricant available, graphite can work as a lubricant. Soap, lip balm and window cleaner have also been listed as alternatives. However, when using any of these methods, be wary of anything that might cause staining.