Car Care Products. Tech Focus: Polishes Everything you’ve ever wanted to know about waxes and polishes but were too afraid to ask. With the summer drawing to a close, now is the time to start thinking about protecting your precious paintwork from the elements to ensure it stays looking its best. But what exactly is in that product you’re holding and how does it actually protect your paint? Words: Jamie King.
With the summer months fading fast it’s time to brace ourselves for the winter months ahead. As well as the usual winter checks, it’s also vital to apply some protection to your BMW’s paintwork to ensure all the grime, road salt, fallout, and other nasties that winter brings don’t get a chance to damage your precious paintwork. That means, far from chucking a bucket of soapy water over the car, you’ll be using a selection of dedicated car care products to revive the life of your paintwork, and then seal and protect it against the elements. But have you ever wondered just what goes into those bottles of polish, waxes, and cleaners that are sat on your garage shelf? Or how they actually do what they do? Well, we have. And that’s why this month we’re going to show you. So grab a cuppa, sit back, and get ready for a polished-based chemistry lesson…
The abrasive powders are what give a polish the ability to restore tired, flatlooking paintwork. The word ‘abrasive’ may sound harsh but in reality the powders used are incredibly fine and quite soft, more like a talc than what you might think of as an ‘abrasive’.
It’s these powders that allow a polish to remove any defects from the surface of the paintwork. They are aggressive enough to remove defects such as oxidation but aren’t so aggressive that they would actually damage the layer of paint itself. Unlike a paint renovator, which is designed to remove the top layer of paint to reveal the fresh paint underneath, and therefore can only be used a set number of times before the paint is physically worn away, a polish is generally soft enough to use all the time without the risk of adversely damaging the paint.
The powders used in paint renovators tend to be more aggressive than those used in polishes and a high performance paint renovator will remove around four to five microns of paint each time it’s used. But to put that into perspective, a human hair is around 100 microns thick! The powders used also have an effect on how easy the product is to use, in particular how easy it is to buff-off.
WHAT IS A POLISH/WAX?
Before we start looking at the chemical makeup of polishes and waxes, we first need to remind ourselves exactly what a polish is. This may sound odd but polishes and waxes are all too often confused with one another – and there is a massive difference between them. A polish contains abrasives to help with paint restoration whereas a wax is purely a surface sealer.
Therefore a polish is technically more similar to a paint renovator than a wax, but most aftermarket polishes include a blend of very mild abrasives and waxes. The composition of the blend also has a huge impact of the product’s characteristics; more abrasives will offer more aggressive paint restoration, whereas more waxes and glaze oils provide deeper gloss and greater protection. Manufacturers will adjust this blend to suit the specific product they are creating.
As a general rule, polishing products will contain three main constituent parts: silicone oils, abrasive powders, and waxes.
The silicone oils do a number of jobs. The first is to give the paintwork that ‘wet’ glossy finish with a deep shine. At the same time, silicone oils help improve the overall appearance by ‘filling-in’ any small scratches or swirl marks to leave a smoother, more reflective finish. As well as complementing the waxes to offer a deeper shine, the silicone oils are also used to help with the durability of the product, and to make application easier.
The waxes within the blend are what give the product its protective qualities and also help provide a deep glossy shine. But there are two different types of wax commonly used together in most aftermarket polishing products: synthetic waxes and natural waxes (such as the famous Carnauba wax). Synthetic waxes tend to offer more durability and gloss whereas natural waxes are famed for their visual warmth and depth of shine. Don’t be misled by Carnauba percentages, as much of the performance in a product comes from the other additives and manufacturers routinely massage the wax content for marketing purposes. The good news is that all waxes, whether natural or synthetic, tend to fill minor defects in your paint, enhancing the finish – a real bonus if it hasn’t been machine polished.
While most polishing products will all include the same constituent parts, the amounts of each will dramatically alter the characteristics of the final product. For example, a blend with more silicone oils and waxes (designed for filling-in surface defects) can result in a product that is better suited to darker colours, offering a deeper shine. Likewise, a product containing more abrasives will have better paint renovation properties than one with fewer abrasives. At the opposite end of the spectrum you have pure waxes that contain no abrasives at all. These are simply a blend of silicone oils and waxes and offer just surface sealing and protection with no renovation properties at all.
It is possible to blend ‘silicone-free’ products, where the silicone oils are removed or replaced with mineral-based oils. These are great for use in environments sensitive to silicone products, such as bodyshops, but they can be more expensive due to the specialist nature of the product, and can also be a little more difficult to use compared to siliconebased products. The reality is that silicone poses no danger to the average car owner, and really just makes products easier to use whilst increasing gloss and longevity of the finish. Avoid silicone-heavy products if you have a car with old or faded paintwork (that can become porous) or if a respray is imminent. Otherwise, leave the worrying to the bodyshops.
DETERGENTS AND SHAMPOOS
As well as all the various polishing and waxing products available to use, taking care of your car also includes washing it. And that should include a lot more than just chucking some washing-up liquid in a bucket of warm water! There’s a huge selection of detergents and shampoos available, all designed specifically for use on cars, and each with their own set of formulated characteristics. Whether that’s removing general traffic film from regular use, heavy brake dust from the wheels, or bird poo from the roof, there’ll be a product that has been specially designed for that purpose. Obviously all shampoo products are water-based as they are designed for use with water. Even products such as wheel cleaners, which could be strong acids or alkalis, are water-based and have to be water-soluble.
WHAT IS A SHAMPOO/DETERGENT?
Shampoo products typically contain surfactants, dyes, and fragrances. The fragrances are there simply to make it smell it nice when you’re using the product, the dyes are there to make the product easily identifiable, and the surfactants are the business part of the product that do all of the cleaning work. Thickeners, water-softening agents and wax could even be added, but surfactants are the key constituent. So what is a surfactant?
Surfactants are surface-active agents that have a number of different roles depending on the product in question. These can include cleaning, foaming, wetting-out a surface, and lifting and suspending soil particles. The structure of the surfactants means that they have one portion that is attracted to the soil particle and one portion that is attracted to water. This means they can lift dirt from a vehicle surface and then allow it to be rinsed away There are four main types of surfactants used in most shampoo and detergent products: anionic; cationic; non-ionic; and amphoteric.
Anionic surfactants are great at foaming and can deal with most different types of soiling. Cationic surfactants are mainly used for their ability to apply a water-repellent film. Non-ionic surfactants work well in detergents aimed at removing greasy soiling. And amphoteric surfactants are good all-rounders with different characteristics under different conditions.
Manufacturers will play around with various blends with some/all of these different surfactants until they have a product that meets the criteria they are looking for.