by Ron Ketcham
American Clean Car, August, 1996

Understanding dressings is essential

Getting the right information in the car care field can sometimes be a problem. Every detailer should be well versed on dressings sold for tires, rubber, vinyl and leather.

The world has become a complex, technical place. Many in the car wash and detailing industries rely on their suppliers to provide not only products but also the technical and "how-to" knowledge regarding product usage.

Unfortunately not all suppliers or distributors have the ability or knowledge to provide accurate information to the trade. Some do not want to divulge what they call "trade secrets,", as the information might be detrimental to their product sales or company image.

Dressings sold for rubber, tires, vinyl and leather are an excellent example of this type of problem, First, let's look at the facts, as I see them, regarding a tire and its physical components.

Tires

The need to protect the rubber in tires from nature's elements is one of the main reasons tires are black. 

Rubber in its natural state is a light gray.

Tire manufacturers mix certain components into the rubber to protect it and increase its useful life. Ultraviolet rays attack rubber just as they attack and oxidize paint. The manufacturers mix certain polymers and waxes into the tire to inhibit ultraviolet and ozone damage to the rubber, particularly the sidewalls. Without these, the tire will degrade and/or dry rot.

Carbon Black is the ingredient that makes tires black. This ingredient is referred to as a competitive absorber. It does its work by capturing and absorbing harmful UV's and converting them into heat so they may be dissipated or thrown off harmlessly.

All UV stabilizers are sacrificial; that is, they are used up. Eventually they can no longer protect the tire from the UV damage and the tire starts to change color. The tire in the final stages may exhibit the rubber's natural gray color.

Ozone is another way nature attacks the tire.

Manufactures include in their chemistry a special anti-cracking/sun checking polymer wax blend. This blend of waxes and polymers retard the ozone from attacking the double bonds of molecules present in the rubber and postpones the surface crazing and checking over a long period of time and a wide range of temperatures.

As the tire moves down the road, it flexes. This flexing action causes the added waxes and polymers to migrate to the surface and form a physical barrier between the ozone and oxygen, which are both oxidizers, and the polymer components of the tire.

This process is referred to as "blooming." The heat generated by the flexing of the tire continually moves minute amounts of the wax to the surface to protect the tire.

When a vehicle is not driven, blooming does not occur; the ozone attacks the protective waxes and then the polymer components. The result is the tire becomes dry, check and given enough time, dry rots. At this point, the sidewall is cracked and unstable. This is a serious safety concern since sidewall failure of the tire is highly probable.

Since nature has its way of destroying a tire, what can we in the different industries do about tires, rubber trim, etc.?

There are several hundred, maybe even thousands of companies and individuals making rubber-vinyl dressings. Use of some chemical components may do even more damage to the composition of rubber or vinyl than nature itself.

We have all seen or used the clear,  greasy-type of dressing. These are usually a simple blend of either kerosene or cheap mineral spirits and a dimethly silicone oil. These hydro-carbon (petroleum) distillates, combined with silicone oils, remove the protective waxes the same way as if you used a ' prep sol' type of product to remove waxes or tar from a vehicle' s painted surface. The petroleum distillates are stripping away the protective components put there by the manufacturers.

Dimethal silicones are just one of a huge family of silicones.

 Body shops have been told for years, "Don' t let any silicones around the paint areas or you' ll have a ' fish-eye' problem." That is correct, if they are referring to the dimethal oil type of silicone. They are an oil and are very migratory. Any oil will create a "fish eye."

Good silicones

What no one has told the operators is that there are all kinds of other silicones and some are in the very paint they are spraying!

What is a "good" silicone? Look for the one of the siloxane or amino functional family. I will not go into deep technical explanations except to say that these types are considered dry and non-migratory. They are what should be used in dressings. The use of these types is more expensive than dimethal oils but may be compounded with little or no petroleum distillates used in the product. A small amount of a highly refined mineral spirits in the products aids in spreading the emulsion over the surface being coated. The use of high-grade mineral spirits allows it to "flash off" before it can attack the protective waxes and polymers. Ford, General Motors and Chrysler have issued advisory or technical bulletins to their dealers to not use heavy petroleum distillate-dimethal silicone dressings for another reason -- paint and wheel staining.

Today' s front and rear bumpers, side molding, etc, require a flex agent to be added to the paint so the paint has a certain amount of "give" or flexibility to it. 

This "flex agent" causes the paint on these parts to be more porous or less tight on the regular painted vehicle surfaces.

When the heavy petroleum distillate/dimethal silicone oil dressings are applied, they dissolve the waxes, polymers, etc. in the side wall and then "sling" or throw them off onto these flex agents parts creating stains. The Big three auto companies have found that it is next to impossible to remove the stains, In some cases, even repainting the part doesn' t work as the stain comes back through the new paint, requiring the part to be replaced.

All factory styled wheels are coated with a clear coat type of coating. Some are more porous than others and use of an incorrect dressing may stain them the same as the body parts.

Now, there is one last major concern with the use of these damaging dressings -- premature side-wide failure. Major tire manufacturers provide warranties against the failure of their products. Should a side wall fail, the first thing to look at is whether a heavy petroleum distillate-dimethal silicone oil dressing was used on the tire. Believe me, the manufacturers can tell, If so, they will not always warranty the tire.

The manufacturers look for certain signs in this area:

• Is the tire greasy?
• Is there evidence of a brown, greasy residue?
• Are the side walls rough, not smooth?
• Has it lost color?
• Is it showing evidence of premature cracking or checking?

The use of a water-borne polymer, siloxane or amino functional dressing is the only way to provide that new tire look, not destroy the tire and actually add protection to the tire' s components. These dry and leave a polymer type of protection from UV' s and ozone while remaining flexible.
Once this type of dressing is dry or "cross linked," it is then water repellent and detergent resistant. It will not attract dust itself; however, the natural blooming action of the tire and its self-generated static electricity will cause a small amount of road dust to cling to the outer surface. Just remember the polymer components of these dressings act as additional anti-oxidant and anti-ozant protection.

Vinyl

Water-borne polymer type dressings are also recommended for use on interior and exterior vinyl components for much the same reasons as when dealing with the tires. 

The only difference with vinyl is that we must protect the plastizers in the vinyl. In simple terms , remove the plastizers and you remove the color and the flexibility of the vinyl. We have all seen dashes, seats, etc. that have a dull or chalky look to them. Check it out, you' ll probably find someone has been applying a heavy petroleum distillate dimethal silicone oil dressing to the vinyl parts. The vehicle manufacturers and their suppliers' work very hard to provide vinyl components that will withstand the punishment of high heat, ultra-violet rays and ozone. The use of the wrong type of dressing negates all their research and chemistry.

Leather seatss

It would seem there are very few of us in the industry who have bothered to analyze what changes have taken place in the manufacturing processes of leather for automotive seats. Years ago to have a leather interior you had to move up to a Cadillac, Lincoln, Jaguar, Ferrari or Rolls.

If you didn' t take special care of the leather it cracked and faded. Why?  I' m glad you asked , the material was simply leather that was dyed. You could not clean it with any type of heavy cleaner or you removed the dye and the leather' s natural oils. So you used, properly, special product to clean and "feed the leather".

Remember how these car seats cracked, etc.? Today, even in an older model car, the seats can look great. The leather has a clear coat. That' s right, just like the vehicle's paint or styled wheels. These clear coats are polymer based. In other words, it' s the result of a hydrocarbon chain that is modified to produce the coating.Special concerns

Earlier I discussed how petroleum distillates (oils) removed or broke down the protective polymers and waxes in tires. Well, that' s what oils or distillates in dressings are doing to the clear coat applied by the manufacturer to protect the leather. The use of the wrong product can break it down, dissolve it and/or shorten the life of the leather.

Don' t assume all leather is clear coated. For example, 1996 jaguars are not clear coated. Test the leather, take some of your caustic interior cleaner and rub it on an area of the seat that no one sees. It works just like the test to ascertain if the paint is clear coated.

If you see the color of the leather on your cloth, it' s time to get out the old "feeding oil." If no color shows, use your water-borne polymer style dressing, let it dry and then buff with a soft, clean towel.

Your customers' vehicles and their lives are important. I can only hope this information serves both of you well for today and in the future.

Ron Ketcham is national sales manager for Automotive International, inc. in Cincinnati, Oh. For further information, contact ketcham at 800/543-7156.