Environmental
damage to paint comes in a varied range of threats; acid rain, industrial
fallout, brake and rail dust, road salt, tree sap, hydrazine an extremely
active acid that is found in jet fuel, ultra violet (UV) and heat radiation,
and other airborne contaminants are very detrimental to a vehicles paint film
surface.
They
are all forms of environmental contamination and given the right catalyst;
reactivity (heat) plus moisture, they will become acidic. During this process the
metal absorbs oxygen from the water and forms iron oxide (rust). Given the
porosity of paint they permeate the paint matrix down to body metal.
The
rate of environmental exposure that negatively effects (clear coat) paint
varies widely with ambient conditions (Ultra violet (UV) radiation,
Environmental Fall-out, paint protection used, etc) but an approximation of
0.0005Mil (0.013µ) per annum is about average; protective coatings polymer
sealants, wax, etc), being renewable are meant to be sacrificial (it is
subjected to oxidation, thereby by saving the clear coat) It's better to have
dust, road tar, tree sap, bug and bird excrement stuck to wax than your paint,
wax also provides a limited paint (sacrificial) protection against acid (i.e.
acid rain, environmental fallout and bird excrement
Most
natural contaminants are hydrophilic, automotive clear coats are generally
based on urethanes, acrylics, melamine’s, silanes, etc. which are hydrophobic
and repel water and other contaminants.
However as the paint surface are subjected to photo-oxidation (sometimes
incorrectly described as oxidation) water beading changes to sheeting and
environmental contaminants will bond to the surface.
Automotive
paint systems are porous; when you add water and heat to an acidic substance it
will erode the paint system very quickly (the heat opens microscopic fissures
in the clear coat allowing ingress, the water provides a carrier system for the
acid, and heat acts as a catalyst each time water is reintroduced the acid will
be reactivated). The paint surface should be periodically neutralized /
decontaminated, i.e. once every two years (See also Reactivity)
Many
natural and synthetic materials are attacked by ultra-violet radiation and
products made using these materials may crack or disintegrate. This problem is
known as ultra violet (UV-B) degradation, and is a common problem in products
exposed to sunlight.
UV
Radiation comprises both visible (UV) light and invisible (UV-A) infrared heat
radiation, which represents part of the ultra violet solar spectrum
(approximately 55%-60%). Organic (Carnauba) waxes or inorganic (polymer
sealants or coatings) contrary to marketing myth do not contain natural ultra
violet protection. Dependent on reflective value of the paint colour; surface
reflection will provide some UV radiation protection along with some
sacrificial protection as the wax or polymers breakdown.
Ultra
violet stabilizer - providing protection from ultra violet radiation (UV) is
very important to avoid photo synthesis (colour fading / yellowing) be
cognizant that ultra violet heat (UV-A) radiation can also affect the
structural integrity of materials by drying out and therefore removing their
elasticity and causing cracks.
There
is no such thing as a permanent UV stabilizer, it a matter of physics, not
chemistry. Ultra violet protection is a sacrificial and therefore a renewable
protection; this is due to the UV protection layer being degraded by exposure
to the elements (sun, sand, road or sea salt, and etc) so it is imperative that
you renew it and it needs to be re-applied on a regular 45 to 60 day basis
(dependent upon location climatic condition)
Dependent
on reflective value of the paint colour; surface reflection will provide some
UV radiation protection along with some sacrificial protection as the wax or
polymers breakdown.
Some
waxes and polymer sealants have ultra violet (UV) protection agents added when
they are formulated, but be cognizant that the protection a microscopically
thin layer can provide is limited. This renewable barrier is probably less than
0.1 µ (4 Mils) thick. The primary paint surface protection against UV light is
the clear coat; which protects the colour coat from fading by adding anti-UV-B
chemicals to the polymer when mixing the clear coat ingredients.
This
renewable barrier is probably less than 0.1 µ (4 Mils) thick. Clear coat paint
(polyurethane) provides the colour and base coats with protection, and usually
has UV protection added in the final coating; this tends to migrate towards the
upper level of the clear coat (this is why it’s important to check how much of
the paint surface you are removing with an abrasive polish). It should be noted
that Carnauba wax does not contain a natural ultra violet radiation protection
Protection
A fundamental
question first; what does a paint surface need to be protected from after all
we should ascertain what we are trying to protect against.
• Ash – from forest fires or volcanic activity can produce an
ash cloud that will settle on a paint surface. Ash is both abrasive (pumice or
wood shards) and acidic when mixed with moisture. Forest fire ash is often
caused by a firestorm, which is a conflagration which attains such intensity
that it creates and sustains its own wind system. It is most commonly a natural
phenomenon, created during some of the largest bushfires, forest fires, and
wildfires
• Acid
rain (sulphur dioxide plus moisture) and is caused
by sulphur from impurities in fossil fuels and nitrogen from the air combining
with oxygen to form sulphur dioxide and nitrogen dioxide. These diffuse into
the atmosphere and react with water to form sulphuric and nitric acids which
are soluble and fall with the rain. Some hydrochloric acid is also formed.
Occasional readings in rain and fog water have resulted in a pH level below 2.5
in some industrialized areas.
For neutralizing acidic type
damage (acid rain, water spots, industrial fallout, for example) then ValuGard decontamination system is a really great choice.
• Artillery
Fungus -the spots resemble asphalt (tar) spots but
could be the spore of artillery fungus they look very much like tar spots and
are usually about 1/10th-inch in diameter, typically artillery fungus feels
like a sticky film, and when flattened can be smeared appearing white. It is a
fungus that lives in wood-based mulch, the spores are usually shot only a short
distance (several feet) but the wind can carry them for longer distances.
• Bird and
Insect Excrement - comprises; Ammonia and urine as
white crystals of uric acid (pH 3.0 - 4.5) a small organic compound, which is
produced by the breakdown of protein during digestion, and is excreted by
reptiles and birds. Uric acid is also the end product of nitrogen catabolism in
birds Ammonia is a mixture of nitrogen gas and hydrogen gas; with moisture as a
catalyst it becomes Ammonium Hydroxide, which is caustic.
• Brake
Dust (FeO) - produced from the friction
of brake pad material (semi-metallic, carbon resins, asbestos or ceramics
formulations) rubbing against the rotor. The brake material friction as well as
metal particles from the rotor disperses tiny particles of black ferrous oxide
dust, which forms a cohesive bond to the wheels and adheres to localized paint
surfaces. Ferrous oxide micro-sized particles that come into contact with
moisture will form rust that permeates deep into the paint's sub-layers. This
is a gradual process that often shows up as tiny red dots or rust spots n the
paint surface, the corrosive damage caused is often not evident until it's too late.
• Bituminous
Asphalt (Tar) -the term asphalt is often used as an
abbreviation for asphalt concrete, asphalt refers to a mixture of mineral
aggregate and bitumen (tarmac) Composed almost entirely of bitumen, which is a
category of organic liquids that are highly viscous, black, sticky and wholly
soluble in carbon disulfide, mostly made up of highly condensed polycyclic
aromatic hydrocarbons
• Bug
Residue and Carcasses - the carcass is very acidic,
and if left for any length of time will cause the porous clear coat to occlude
(a non-transparent ‘clouded’ area) or may cause etching (a depression in the
paint or glass surfaces) their exoskeletons will also scratch the paint surface
• Calcium
(Ca) - an untimely lawn sprinkler, a springtime
shower, or spots that remained after washing, the minerals are white
calcium/sodium deposits that are alkaline-based, especially from hard water. If
left on the vehicle paint surface they act the same way as acid rain in that
they will etch the paint film surface.
• Contaminants
- particles of dirt, grime, carbon emissions from
catalytic converters, bird excrement, calcium, tar, oil, hard water deposits,
calcium or any pollutant type substance that adheres to your paint surface,
sometimes invisible the naked eye.
• Corrosion
(metal oxidation) - Salt water conducts electricity
better than fresh water so in areas that use salt on the roads, this process is
greatly accelerated. Corrosion (rust) destroys metal by an electrochemical reaction with water as the catalyst (water + ozone (an oxidizer) moisture +
oxygen).
• Detergents
(Harsh) - They are usually a blend of several
surfactants, which are two opposing polar groups, hydrophilic and a non-polar
group lipophilic. Surfactants use emulsification to dissolve and encapsulate
oily particles. Paint surface protection (wax, polymers, coatings, etc) are
formulated to be detergent resistant, but be cognizant that the harsh high
alkaline detergents used in high street carwash, especially no-touch tunnel
wash will strip away a large percentage of wax and a percentage of polymer
sealant, leaving the sacrificial barrier compromised
• Exhaust
Gas Emissions- the exhaust gases which are
discharged from the engine contain several constituents that are harmful to
human health and to the environment. Carbon monoxide (CO), hydrocarbons (HC),
and aldehydes are generated in the exhaust as the result of incomplete
combustion of fuel.
A
significant portion of exhaust hydrocarbons is also derived from the engine
lube oil. Hydrocarbons also have a negative environmental effect, being an
important component of smog.
• Hydrazine
- an extremely active acid that is found in jet
fuel, vehicles that park in close proximity to airports or flight-paths are
subject to this contaminant. Park near idling diesels or an airport with a lot
of jet fuel exhaust in the air; kerosene strips waxes or sealant; diesel and
jet fuels are refined kerosene.
• Infrared
Radiation (IR) - represents part of the ultra
violet solar spectrum (approximately 55%-60%). The remaining heat source comes
from visible and ultra violet light Infrared radiation (IR) infrared radiation
is a light source that transmits heat that will cause oxidation by drying out
materials, like the paint (binder) resin system, the plasticizers in vinyl,
moisture evaporation of leather and the elasticity of rubber causing these
materials to dry out and become brittle and compromise their structural
integrity. Ordinary auto window glass filters out about 35% of IR radiation.
• Industrial
Fallout (IFO) - emissions from power generation,
manufacturing plants and combustion engines emit Sulphuric acid from their
exhaust stacks etc, vehicular catalytic converters emit carbon compounds that
mixed with ozone (an oxidizer) and water becomes Sulphuric acid. Nitric oxide
is an additional IFO component especially around Paper Mills.
When
these pollutants alight on a surface they are neutral; forming a dry
concentrate of acid (a dioxide, or dry substance of the compound). Water is
added in the form of morning dew, fog, smog or rainwater, which contains two
hydrogen atoms, and an oxygen atom. Oxygen is an oxidizer, ozone is an
allotropic form of oxygen, and an oxidizer is any component that emits oxygen;
many chemical compounds react to slight heating and an oxidizing process.
So
now you have an acid + water +oxygen + ozone all of which equates to a highly concentrated
acidic solution, which causes a concave indentation on the paint surface (the
misnamed ‘water spots’) (See also Reactivity) Information resource- U.S.
Environmental Protection Agency (EPA) website
• Oxidation
- (reduction) - is caused by environmental
pollutants (acid rain, ozone, industrial
pollutants, hydrocarbons, etc)t UV- B
radiation is known to contribute to the chemical modification of exposed paint
surfaces resulting in loss of gloss, colour change, chalking, flaking and
eventually destruction of the paint film. Inclement weather or the use of harsh
detergents in commercial car washes using strong detergents will leach out the
oils in the paint and dull the paint film surface even faster
It
starts as a chemical reaction that causes the paint film surface to overheat,
dry out and oxidize leaving microscopic surface imperfections and micro pores
in the paint film surface that are vulnerable to deterioration.
• Ozone - when the air temperature reaches high 90 – 100.0F,
plants and trees, which normally give off relatively small amounts of isoprene,
started to produce greatly increased amounts. It is thought that isoprene,
which is released by deciduous trees, and terpene, which is emitted by
evergreen trees, help protect leaves from heat and sun damage.
In
the atmosphere isoprene and terpene act as catalysts, increasing the rate at
which sunlight breaks down nitrogen oxide - a car pollutant - into ozone. The
more isoprene and turpene there is the more ozone is produced from smaller
amounts of nitrogen oxide.
• Pollen - the yellow fines to coarse powders you see in the air is
made up of small sperm cells from blooming plants and is one of the most common
allergy triggers. The pollen from trees are the main concern, vehicles get hit
with pollen laced trees that include: oak, western red cedar, elm, birch, ash,
hickory, polar, sycamore, maple, cypress and walnut (which also leaves an oily
residue). Pollen grains of pines, firs, and spruces are winged.
• Rain - liquid precipitation, as opposed to non-liquid kinds of
precipitation such as snow, hail and sleet. Clean rain and 'as pure as driven
snow are both things from a non-industrialized past, before (acid rain,
hydrazine (airports) and industrial fallout (IFO)
Emissions
from power generation, manufacturing plants and combustion engines emit
Sulphuric acid from their exhaust stacks etc, vehicular catalytic converters
emit carbon compounds that mixed with ozone (an oxidizer) and water becomes
Sulphuric acid. Nitric oxide is an additional IFO component especially around
Paper Mills.
The
pH of rain varies, especially due to its origin. The US east coast, rain that
is derived from the Atlantic Ocean has been typically recorded at a pH of ~
5.0; rain that comes across the continental from the west has a pH of 3.5-5.0;
and local thunderstorms can have a pH as low as 2.0. Rain becomes acidic
primarily due to the presence of two strong acids, sulphuric acid (H2SO4)
and nitric acid (HNO3). Sulphuric acid is derived from natural
sources such as volcanoes, and wetlands (sulphate reducing bacteria); and
anthropogenic sources such as the combustion of fossil fuels, and mining where
H2S is present.
Nitric
acid is produced by natural sources such as lightning, soil bacteria, and
natural fires; while also produced anthropogenically by the combustion of
fossil fuels and from power plants. In the past 20 years the concentrations of
nitric and sulphuric acid has decreased in presence of rainwater, which may be
due to the significant increase in ammonium (most likely as ammonia from
livestock production), which acts as a buffer in acid rain and raising the pH
Sediment
precipitation is a weather condition that occurs when a mix of rain and
sediment (usually as dust or sand) fall from the sky as precipitation. It
usually occurs in arid desert regions such as west Texas or Arizona
• Road
Salt - Although salt is inert when subjected to
freezing (15 – 20.oF ) it’s considered the lower limit for salt to melt
snow/ice but once H2O, even in the form of moist air (i.e. humidity) is added
the freezing point is lowered and the saline solution(salt/water) will have an
adverse effect on the vehicles paint and undercarriage.
When
washing the vehicle ensure that all salt is removed to avoid a saline solution
remaining on the paint finish. Using a durable protection (Collinite Insulator
Wax) will provide a sacrificial and renewable protection to the vehicles paint
finish.
• Rail
Dust - ferrous oxide (FeO) a
black-colored powder that is created by railroad wheels abrading the metal
tracks, these small particles become airborne and are sintered to the paint
film surfaces. New cars that are transported by rail are at extra risk. When
moisture combines with the oxide particles it creates small rust spots.
• Sand - dust storms arise when a gust front or other strong wind
blows loose sand and dust from a dry surface. Particles are transported by
suspension, causing soil erosion from one place and deposition in another; it
will also erode a paint surface. The Sahara and dry lands around the Arabian
Peninsula are the main terrestrial sources of airborne dust, with some
contributions from Iran, Pakistan and India into the Arabian Sea, and China's
significant storms deposit dust in the Pacific and sometimes much further
afield.
A
major dust storm swept through the southern portion of the Desert Southwest
U.S. State of Arizona in 2011. The dust storm was triggered from thunderstorms
to the south of the Phoenix metropolitan area. Dust from the deserts was blown
up by high winds. The winds were estimated to be over 60 miles per hour and
caused low visibility.
• Ultra
violet radiation – (UV) light radiation is a paint
film surface's greatest enemy, causing more damage than any other airborne
contaminant and affecting both the interior and exterior of a vehicle.
The
light in this spectral range is responsible for photo degradation. Photo
degradation results in discoloration, fading, embitterment, cracking, chalking
and/or loss of mechanical properties. Ordinary auto window glass filters out
about 95% of UV radiation.
• Tree
resin (sap) - appears like a dark brown/ rust red
colour raised surface mark, some of the most common resinous tree sap types
are: White Pine, Ponderosa Pine, Walnut (also secretes an oily residue) Maple,
Oak, Popular, and Blue Spruce, none of which are water soluble, the acidic
content of the sap will etch the paint surface; causing a concave surface.
• Water - beading that is left to evaporate on a car will lead to
water marks; a standard household supply usually contains alkali minerals like
calcium(Ca) magnesium (Mg), which are inert until heat and moisture is added
and then it become corrosive. Once these form a ‘bead’ and they dry they will
cause etching (a shallow indentation) of the paint surface. Clean rainwater
(See also Acid Rain) has no harmful effects. The average unprotected
water-based paint absorbs approximately a pint of water; dependent upon its
content this may be harmful.
• Water
Marks (Water Spots) - the misnomer ‘water spots’
are likely to contain the atmospheric pollutants nitrogen oxide from motor
exhaust emissions and sulphur oxide emissions from chemical plants, paper
making and refineries, all of which can cause paint discoloration, surface
etching and leaving microscopic surface imperfections and micro pores in the
paint film surface that are vulnerable to deterioration, which should be removed
and naturalized as soon as possible.
These
spots are recognizable by white or chalky rings that make the paint appear
cloudy. Acid (acid rain, industrial fallout (IFO) hard water minerals (calcium
and magnesium) alkali (from a sprinkler system) and of the above when mixed
with moisture and heat (reactivity) will cause etching ((a concave circular
mark and pitting)) each time moisture and heat are added the acid / alkali is
reactivated and it permeates further into the paint surface, if left for too
long they can become too deeply ingrained in the clear coat for ‘safe’ removal.
If
not removed, these minerals can permanently etch paint and glass. Quick
detailers typically contain a wax or polymer and water, using them on an acid /
alkali will lock the acid, allowing it to react with moisture and heat, which
makes the acid more aggressive
Reactivity
[: acceleration of a chemical reaction by a catalyst]
Be cognizant
that an acid is inert until it comes into contact with moisture; like ike any chemical attacking a surface, temperature will dictate
reactivity (acceleration of a chemical reaction by a catalyst [moisture and heat]. The more heat and
moisture that is present (in the form of high humidity, dew and etc) the more
aggressive the acid becomes.
Then
you have; an acid + water +oxygen + ozone all of which forms an acidic oxygen
molecule that causes a concave indentation (acid etching) to the paint surface
it should be noted that until this acid is neutralised subsequent moisture and
heat will reactivate the acid and allow further damage, as acid requires an
alkaline to neutralize it
This will cause surface etching (an
indentation of the clear coat) so they should be removed without delay. In this
case, paint care not only serves aesthetics, but also helps preserve the
vehicles. At lower temperatures (>
40.oF or less) there’s no reactivity and therefore little or no
etching.
Sacrificial
Protection
Sacrificial [:
designed to be used up or destroyed]
A
paint or metal surfaces natural sacrificial protection is oxidation; the so
called white rust on aluminium is in fact oxidation. Eventually, any mechanical
abrasive action will wear away the oxidation; this could be caused by washing
the paint surface, using a car duster, placing or removing a car cover, etc.
The
micro thin layer of wax or polymer sealant, apart from their aesthetic
qualities provides a film that resists the adhesion of dirt and etc and allow
you to wash the paint surface without using undue pressure, thereby micro
marring the paint. Be cognizant that they are limited in their ability to
resist scratches, although some Finish Kare FK1000P for instance provides
better protection than most.
Products
like Klasse an acrylic polymer is acid based and is resistant to acidic attack,
or an inorganic wax like Collinite 845 Insulator Wax or Finish Kare FK1000P is
probably the most durable inorganic wax product, but this will only provide
enough of a barrier to enable it to be removed quickly before causing too much
(etching) damage to the paint film
The nanotechnology coating or PPG CeramiClear™ Clear Coat although they are
highly resistant to chemicals, detergents, scratches and ultra violet radiation
(UV) will only offer limited resistance to acid etching from environmental
contaminates. The newer nanotechnology coatings are better than conventional
last step products (LSP) i.e. Aquartz silica coating. Although there are no
products to-date that can protect against bird excrement or other environmental
acids
Carnauba
wax forms a multi strata matrix, whereas a polymer is a mono layer that
cross-links and forms a chain like structure that forms a molecular bond to the
paint surface. Contaminants will be further removed from the surfaces that are
protected with a Carnaubas multi strata matrix than with polymers mono (single)
layer
Wax
coatings act as a sacrificial buffer between a paint surface and the elements;
these coatings are gradually used up (hence sacrificial) and reach a point
where they can no longer protect; when they reach this point they must be
renewed. Once attacked by acid (acid rain, Bird or Insect excrement, Industrial
fallout, and etc) it should be removed and a fresh coating applied.
They
are all forms of environmental contamination and given the right catalyst;
reactivity (heat) plus moisture, they will become acidic. During this process
the metal absorbs oxygen from the water and forms iron oxide (rust). Given the
porosity of paint they permeate the paint matrix, causing erosion down to body
metal.
No
wax, polymer sealant or nanotechnology coating on its own, can provide a
permanent shield against acidic attack from bird excrement, acid rain etc as
they are all incompatible with strong acids.
Many
natural and synthetic materials are attacked by ultra-violet radiation and
products made using these materials may crack or disintegrate. This problem is
known as ultra violet degradation, and is a common problem in materials that
are exposed to sunlight.
UV Radiation
Protection Provided by Auto Glass
Glass
tinting and UV film protection are important ways to reduce exposure to UV
radiation, which are the primary focus of the glass tinting and film tinting
industry.
While
a car provides substantial shading, the glass areas do not block UV. And, as it
is not uncommon to spend several hours a day in a car, the implications for
skin problems are high. Further, damage to eyes from glare and direct UV
increases the more people drive.
American
federal laws on auto glass are based on visible light transmission. They allow
only for a vehicle's driver side and passenger side windows to be tinted up to
70% visual light transmission (VLT), which is also the normal factory tint
found on most new cars. The focus on visible light transmission is driven by
safety issues. The tint can be reflective which is dangerous to other drivers
and/or can be dark to see through at night. If you do tint your car windows,
you want to minimize UV transmission through the glass while allowing 70% or
more visible light transmission.
Modern
cars are being designed with inherent protection features, ordinary car window
glass filters out about 97% of the (UV-B) radiation, the cause of
photosynthesis (fading) and approximately 37% of (UV-IR) infra red (heat)
radiation, modern clear coat paint also contains UV inhibitors.
Most
automotive ultra violet (UV) absorbers are very durable and exhibit a 5 year
half life, meaning that every five years the concentration is reduced by 50%
percent.
New
car owners mistakenly believe their new vehicle cannot be damaged by sun
exposure. Due to the ozone layer depletion (global warming) in our atmosphere,
UV radiation strength is increasing. Protecting your vehicle from UV radiation
damage continues to be a very important.
An
organic wax, contrary to popular opinion, or marketing, does not contain
natural UV protection; the wax protects the leaves due to its thickness and the
fact that it’s opaque. It does however provide a sacrificial surface that will
resist acid (salt brine, bird excrement, acidic rain, etc) better than a
polymer, which forms a molecular bond with the paint, whereas a an organic wax
forms a semi-hard protective shell (although it lacks durability)
Protection from
Environmental Contaminants
The
following are things you can do to provide protection-
• Use
a polymer paint sealant product on your car several times each year. A carnauba
wax, contrary to popular myth (or is it marketing BS) does not contain inbuilt
natural UV protection, this component must be added. . This sacrificial
protections effectiveness lasts for no more than 2-3 months.
• For
long-term paint protection use a coating (Opti-Coat™ or Modesta) its effectiveness lasts
for 2-3 years
• Use
a vinyl and rubber protectant with UV inhibitors on all exterior vinyl and
rubber twice a month.
• Protect
fabric and leather upholstery and carpet (especially in a roadster) with a UV
and stain blocker treatment twice a year.
• Use
a sun shield in your windshield when parked outside.
• Cover
your car when parked outside for extended periods.
These
simple measures will ensure your vehicle's appearance has a chance of remaining
in excellent condition for ten or more years. If you take no precautions, its
appearance will noticeably deteriorate in less than five years
If
you need advice on how to remove any of the above environmental contaminates
send me a PM or ask your question either here or in the main forum.
Over Polishing Paint
Polishing
alleviates a myriad of paint aesthetic surface problems. But use abrasive polishes wisely
to maintain paint condition and to resolve surface damage problems. But know
when to seek alternative methods of damage control and avoid over polishing
with harsh, abrasive polishes.
I would like to
think that these articles become an asset to anyone who is new to detailing and
to professionals alike, as well as industry experts who seek to advance their
knowledge.
I hope the
above article was informative. By having some understanding of the ‘What’ and
‘Why’ as well as the ‘How’ along with a little science to help you understand
how the chemicals we use react, you can achieve the results you desire.
I would appreciate it if you
would share this article as it helps other detailers further their knowledge.
Questions and/ or constructive
comments are always appreciated.
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© 2002 - 2012 TOGWT® (Established 1980) all rights reserved
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