There are two types neither are pleasant copied this info from the web
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Brake Cleaner Ingredients
by Jason Unrau
There are two main
variations of brake cleaner: chlorinated and non-chlorinated. Both have similar
functionsand degreasing properties, but they are composed of very different ingredients.
Tip
- Brake cleaner is a skin and eye irritant. Don safety clothing and eyewear when using brake cleaner.
Brake cleaner is toxic. If ingested, contact a poison control center immediately. Do not eat or drink when using this product.
Chlorinated Brake Cleaner
Chlorinated brake cleaner is nonflammable; however, it is harsh on your skin and is known to be a possible carcinogen. It is made of two components:
Tetrachloroethylene
This solvent -- also known as perchloroethylene -- is the primary ingredient in this kind of brake cleaner. It is used to remove materials from metal that are not water-soluble. This includes grease, oil, brake fluid and brake dust.
Carbon Dioxide
Carbon Dioxide is used as a propellant in the aerosol format of
brake cleaners.
Non-Chlorinated Brake Cleaner
Comprised of different chemicals than chlorinated brake cleaner, this version is extremely flammable but is less harsh on your skin. It contains:
Heptane
This chemical distilled from oil is used primarily as a solvent to clean contaminants from metal parts and is not water-soluble. It is safe for use on ABS brakes, as well as disc and drum brakes.
Acetone
This solvent is used to clean contaminants from parts. It is particularly useful in removing water-based contaminants, as it absorbs water.
Carbon Dioxide
This gas is used as the propellant in non-chlorinated brake cleaner.
Tip
- Non-chlorinated brake cleaner is flammable. Use it in a well-ventilated area away from open flames, hot surfaces and sparks. Do not smoke around brake cleaner