Acid Rain: Paint Finishes Can Be Saved By Ron Ketcham – Reposted from Auto Laundry News – March 1997
All of us have read seen TV shows, and heard horror stories about acid
rain. Unfortunately most information regarding acid rain and automotive
paint finishes is at least slightly incorrect or, in some cases, totally
wrong. Let’ s set the record straight and clear away all the old wives’
tales about acid rain. With that accomplished, you should be able to
explain to your customers what it’ s all about.
WHAT IS ACID RAIN?
Manufacturing plants, power-generating plants, internal combustion
engines, jet engines, etc. all produce sulfuric dioxides, which are
released in their exhaust fumes. Smog, well known in major cities,
contains these chemicals. When smog settles on a surface such as an
automobile fender it is known as industrial fallout, or IFO. When ozone,
water and heat are applied to IFO it becomes acid rain, right on the
paint’ s surface. You may ask, “Don’ t catalytic converters on our cars
get rid of sulfuric emissions?”Only partially. Whatever changes the
converter accomplishes in the sulfuric compounds are reversed by the
effect of ozone and water. Nitric oxides are additional acid rain
components. The nitrics were originally thought to be a large part of
the problem. However, recent data have shown they are not a real
contributor to acid rain problems on vehicle paint finishes; there are,
of course, exceptions. While all manufacturing plants contribute to the
nationwide pollution problem, one type stands out as an example of a
sever localized producer of acidic contaminates: paper or pulp mills.
These mills use an acidic process to break down wood fiber. A major
portion of the acid compounds utilized is nitric acid. The nitric acids
combine with other acids emanating from the process to create a mini
acid-rain belt in the area around the facility.When the emitted acids
combine with particulate matter and then settle on an automobile finish,
severe acid etching may take place in a very short period of time.As a
result of this localized pollution problem, many paper mills have a car
wash on site so employees can remove the acid compounds from their
vehicles at the end of their work shift. Others contract with a quality
local car wash to clean their employees’ vehicles.A far worse emission
is hydrazine. This extremely active acid is a component of jet fuel. So a
vehicle parked regularly around a major airport or in high-usage flight
paths will be subjected to hydrazine acids on its painted surfaces.
Hydrazine is extremely reactive to oxidizers such as ozone.An oxidizer
is any compound that spontaneously emits oxygen either at room
temperature or under slight heating. Many chemical compounds react
vigorously at ambient temperatures as the oxidizing process takes place.
Hydrazine, due to its molecular chain of hydrogen and nitrogen atoms,
reacts violently, eating at any surface where it is concentrated. Any of
us who took basic chemistry in high school or college remembers our
instructor’ s caution: “Always add the acid to the water — never, never
add the water to the acid! So what’ s that have to do with acid getting
on a car’ s paint? Here’s what is so important to our understanding of
acid rain and protecting the paint and reducing or eliminating its
effect on the paint film:
When acid rain lands on the paint film surface, it does no damage! That’ s right; it does not hurt it one bit! However..
The water evaporates from the paint film, leaving behind dry
concentrates of the acid compounds, hydrazine etc. We now have a
dioxide, or dry substance of the compound. The vehicle is subjected to
water in the form of dew, rain, and the like. The acids are no longer
dry. Water is made up of two hydrogen atoms and one oxygen atom. Oxygen
is an oxidizer. Ozone is an allotropic form of oxygen, an oxidizer.
The acid com- pounds start penetrating into the paint
film and concentrating more and more each time the vehicle gets wet with
plain water. Each time, these acid compounds eat away more of the
paint’ s resin system, the former and binder of the paint system.
If you look at a highly- magnified cut-away of a
base/clear-coat paint system, it resembles a sponge. The resin system is
what holds the sponge together That is why acid rain damage is seen as
an etch or pit. Part of the system has been corrosively eaten away.
Let’s now put all of this into perspective:
Acids are generated by our industrial processes, whether in California, New Hampshire or Montreal.
These acids mainly cause paint damage when they concentrate and are re-exposed to water, ozone and heat.
Simply rinsing a vehicle with deionized water or tap water activates the acid concentrates.
The acid concentrates eat away the paint, creating
discoloring, etches, and pits, which most consumers and even car care
professionals think are water spots.
Acid Burn on Door – Before and After Sequence
“El Niño” is Spanish for “the boy child.” It is also a term used for a
global weather pattern that pops up every few years and may hang around
for two or three years. Its intensity varies each year. El Niño starts
near the western coast of South America, warming the air currents and
waters of the Pacific south of the equator and continues over to
Indonesia and environs. It then turns moves east, now north of the
equator, across Mexico and into the Gulf of Mexico and the Caribbean. El
Niño pumps warm, moist air into its area. If conditions are in sync
with the jet stream, it pulls more warm, moist air out of the gulf right
up through the center of the United States and Canada. Current
projections by some weather observers are for 1997 to produce an El Niño
pattern. Acid rain may very well be extremely active this year;
resulting in hundreds of millions of dollars in paint damage. As El Niño
travels, it picks up industrial pollutants and generates acid rain. El
Niño causes quick, short warm rains as well as heavy storms. The quick
warm rains are more of a problem because:
They deposit the acid-laden rain on vehicles that have warm or hot surfaces.
Since the vehicles are warm or hot, the paint film is softer and
more porous and allows the acids to penetrate into the film or lock onto
it. The water quickly evaporates, leaving the acid in a concentrated
It rains again and the process starts all over but in a more concentrated form.
All the dark colored cars start showing “water spots” and then
discolored spots as the acid rain progressively etches and pits.
Eventually even the white and light colored cars start to show the same
Everybody gets mad at the automobile manufacturers and paint
suppliers because they think the damage results from poor paint.
Everybody is wrong — there is nothing wrong with the paint — they just don’t know what’s happening.
You do-now! But what do you do about it?
Saving the paint from the dreaded acid rain is really very simple, and
everyone can do it.Automobile manufacturers use transit coating or a
white plastic sheet to protect the vehicle during transportation against
the damaging effects of environmental pollutants. But what can we do
once the protective covering is removed? Read on, there is an answer.
HOW TO SAVE YOUR PAINT FINISH
Have the paint “decontaminated” with an approved chemical system. It is a
simple washing process, performed by trained certified professionals.
It does absolutely no good to buff, polish, wax or paint-seal a vehicle
that has been exposed to acid rain. Remember, the paint is like a
sponge. The acids enter the sponge and are concentrated.
Every time the vehicle gets wet, some moisture penetrates the sponge and
reactivates them. The acids must be removed or, like that pink rabbit
banging away at his drum, they’ll just keep going and going, eating away
at the paint.
Once the paint has been decontaminated, have a high quality polymer
paint sealant properly and professionally applied. Quality products
contain polymers, co-polymers and amino functional resins. These
components are heat and detergent resistant, and anti-corrosive. In
other words, they fight off the effects of corrosives such as acid rain,
the acid in bird droppings and industrial pollutants found in IFO.
Have your vehicle washed at least once a week.
Regular washing is perhaps the most effective deterrent (when combined
with a quality polymer paint sealant) against acid rain.
Remember: A little more time and a few more cents spent on regular
maintenance of you vehicle could save you thousands of dollars later.
Ron Ketcham is with Cincinnati, OH based Automotive International Inc.
Ron has over 30 years experience in the industry. He wishes to
acknowledge the contributions of John Hughes, Ford Customer Service;
Richard Salceda, Mazda Motors, America; Erick Buxton, Hyundai Motors,
America; John Crow, Porche Cars North America; Fred Daws, Chrysler
Canada, Ltd.; Ron Otterman, Project Consultant, Ford Motor Co.