Traditional automotive waxes are made from carnauba wax which is produced from Brazilian palm trees. Raw carnauba is usually very hard and coarse(see images below). It is further refined and processed with carriers, oils and other solvents so that it can become a paste, allowing it to be applied to the car's paint. These waxes offer hydrophobic properties, a unique wet glossy look and protection from ultraviolet rays. Most traditional Carnauba waxes last only a few weeks and attract a lot of dust while costing a chunk of the wallet. This is where sealants shine. (Unintended pun!)
Sealants cost less than waxes and offer longer protection as well. Their durability can range from a couple of months to a year depending on the polymers in the sealant. A great benefit of sealants is that traditional carnauba waxes can be layered on top of them giving the car the warm-wet appearance of the wax while retaining the extended protection of a sealant. Sealants, similar to waxes, can be applied using hands or a buffer with a non-abrasive soft foam finishing pad.
Most sealants are 0.01-0.02 microns thick. Think of it as 1/200th of a 3M post-it card. Quite thin right? They are still a great way to protect the car until we came up with...
Coatings are usually thick ceramic-based high gloss barriers against environmental contaminants. A ceramic is a nonmetallic solid that is created by heating and then cooling and their material and mechanical properties (such as hardness, fracture toughness, shear strength) can vary depending on the heating and cooling. Coatings are extremely tough and resistant against chemical erosion and chipping. However, they come with a price tag higher than sealants. Most coatings are 50-100 times thicker than traditional waxes and sealants. Their adhering action is very similar to sealants as they start bonding to the clear coat and each other by crosslinking and creating an impenetrable barrier as soon as they are exposed to air. Some coatings, such as Opti-Coat Pro, once bonded doesn't bond to itself and the only way to remove it is by abrading it away! They are ideal for people who like to set-and-let-go without having to worry about regularly waxing the car.
Coatings can last from a year to the entire lifetime of the paint. They are made from formidable compounds such as Silicon Dioxide and Silicon Carbide which have Mohs hardness rating of 6-9 which are much harder than VOC compliant factory clear coat paint finish.
One of the best features of coatings it that most of them can bond to wheels, headlights, windows and trim to provide long last protection from UV and airborne contaminants. Another great benefit is that they can also be layered with a traditional waxes, giving the look of a waxed car and protection of a coating. On its own, coatings usually create a 'candied' look.
For those who are always on the go and enjoy ease-of-application products, spray waxes are a great option. It is easy to underestimate the power of spray waxes and rightfully so, until recent developments in polymer chemistry have allowed them to be totally standalone rather than just a supplement. Spray waxes can be either or both carnauba or polymer based. Most of them are simple spray, wipe and buff products that allow a sedan to be sealed/waxed in 15 minutes to half an hour.
It is important to note the distinction between standalone 'spray waxes', 'booster waxes' and 'detail spray' despite having similar methods of application. Booster waxes are used to bring back the slickness and gloss of a newly waxed car while not extending the durability of the original coat of wax or sealant. Detail sprays are used to safely wipe down light dust or dirt that has accumulated on the car. (Please, do not use a duster to remove light dust! It's very harmful to your car!) It is recommended to consult with the product manufacturer before buying such products to find out about their durability, safety and application method.
There is a solution out there for everyone. The technology is consistently improving and various products are out there that offer excellent protection and distinct appearance.
Photo Credits: Rachel Simpson Photography & Wikipedia.