Ty
05-03-2009, 11:56 PM
Clear Coat Failure (Paint Oxidation)
Oxidation (Reduction): [simply means that oxygen is added to a molecule with an electron being displaced, which in turn dries the paint surface].
A sound understanding of the proper technique and the correct process will produce excellent results even with a mediocre product. A quality product used without the proper surface preparation or application technique will never obtain a satisfactory result. Using the proper methodology (surface preparation, using a quality product, along with the correct application technique) will ensure an excellent result.
Skill Level / Experience
Some methods described may be beyond the capabilities of the average detailer or enthusiast; in this case we strongly encourage the reader to consult a professional detailer or body shop concerning the matters discussed herein.
Liability
The writer assumes no responsibility, expressed or implied, due to misuse or misinterpretation of the information or methods used, or for any vehicle damage or injury that may occur due to the suggestions and information offered.
Product Quality and Technique
Proceed with this in mind; the products you use constitute a very small factor in the equation. Methodology and technique constitute 95%; the reasoning behind the choice of quality products is to eliminate any limiting factors, thus enabling you to place emphasis on technique used.
Thickness - a clear coat has a thickness of 1.5 – 2.0 Mils, removing more that 0.4 mil (0.0004") of clear coat will cause premature paint film failure. As a point of reference two sheets of Saran wrap placed on top of each other measure 1.5Mil (0.0015") a surface scratch that will `catch' your fingernail is approximately 0.004" deep and will usually require wet sanding and refinishing. Moderate to light polishing will remove approximately 0.025 Mil of paint. There comes a point when you must judge wither removing a scratch will compromise the clear coat and if so you’ll have to ‘live’ with the imperfection
Ultra Violet Radiation
Clear coat paint (polyurethane) provides the colour and base coats with protection, and usually has UVR 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) once this is gone there is no UVR protection for the basecoat and this will cause clear coat failure (oxidation) and photo degradation (fading) of the colour coat
Water-based paint is very porous, the paint film surface on a microscopic level has many surface imperfections, and is convoluted (a series of peaks and valleys) with time and use, plus normal wear and tear, the surface becomes more permeable, thus allowing ingress. High solid clear coat during the first couple of months, following factory painting will allow moisture to enter the clear and become trapped. This is most noticeable in vehicles that are transported, using transit wrap, when the surface has some moisture and the wrap is placed over it.
On average, a high solid clear coat will absorb approximately one pint of water when the vehicle is subjected to a heavy rain or a car wash. If there is a "clouding" of the clear, simply applying isopropyl alcohol (IPA) to the area, allowing it to dwell and with a heat gun or hair dryer, heat the area (do not exceeding 100.oF spot temperature) The IPA acts as a "drying" agent, and when combined with the heat the moisture will evaporate.
The rate of environmental exposure that negatively affects (clear coat) paint varies widely, but experience shows that 0.0005 –inch (12.7 Microns) 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) Using a moderate to light polish; and utilizing a rotary polisher will remove approximately 0.000025 - inches (0.635 Microns) from the paint surface (they are many variables such as polish/compound and speed / pressure used that may affect the paint removed)
Clear coat paint (polyurethane) provides the colour and base coats with protection, and usually has UVR 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)
Detailing clay has made a huge impact in paint finish care because it removes oxidation and allows the paint to remain healthy, longer. Applying a coating over a paint finish does not stop oxidation; it only slows it down. Waxes with cleaners are better for your paint finish than those without; because they strip away some oxidation and allow the coating to obtain a better hold (anchoring to the micro-fissures of the surface) and lasting longer to retard oxidation. Those of us who properly prep the paint finish prior to waxing do not need these cleaners, but they still help.
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. Oxidation is caused by environmental pollutants (acid rain, ozone, industrial pollutants, hydrocarbons, etc) the suns heat, which also causes paint colour fading from ultraviolet radiation (UVR) inclement weather or the use of harsh detergents, all of which attack the paints binder system(resin)
It starts as a chemical reaction that causes the resin binder system to overheat and dry out, leaving microscopic surface imperfections and micro fissures in the paint film surface that are vulnerable to deterioration. Once the air borne contaminates and pollution compromises the paint surface they accelerate the oxidation (reduction) or paint failure process.
Two- stage paint system- (base, colour and clear coat) - a clear-coat finish does not oxidize in the true sense of the word; meaning that the pigments and resins mix together and the pigments are exposed to the sun's ultra-violet rays, which causes them to dry out or oxidize. The clear coat is applied to protect against this but the finish will become ‘dull’ by using harsh (abrasive) or if acidic car washing solutions as used in ‘touch less’ car washing systems, or from industrial airborne pollutants compromising the clear coat allowing the suns heat to dry out (oxidize) the paint.
The clear coat layer is extremely thin (1.5 – 2.0 Mils) it is not a solid coating and is to some extent porous, oxygen interacts with substances in the paint layer (i.e. mica flakes as in metallic paints) and trigger the oxidation reaction. It's just that the amount of oxidation taking place is minimal in comparison to single stage paint.
For oxidized paint try the following;
•Wash the paint surface and dry thoroughly
•Clean the paint with chemical paint cleaner (Klasse All-In-One) using an orange foam pad at speed #4, this may take 2-3 applications
•Once the oxidation has been removed use a decontamination system (Auto International A B C System (Automotive International - Valugard Product Line)
•Apply an oil rich product to stabilize the paints binder system (3M Imperial Hand Glaze) apply a thick coat and allow to dwell for 12-24 hours before buffing, repeat as necessary until surface has an ‘oily’ sheen.
•Remove residue and apply a Carnauba wax (Zymol Concourse)
•Try to keep vehicle paint surface away from UV heat radiation
•Keep paint surface waxed on a regular basis.
Single-stage paint systems (base and colour coat) – (note-single stage paint is usually very ‘soft’) without a clear coat to provide protection, primarily a hostile environment will attack the paint surface causing microscopic gaps and valleys (micro fissures) and it becomes compromised both chemically; by industrial fallout (IFO) acid rain, brake /rail dust and etc., and by UV heat radiation, which causes it to dry out and/or fail, causing the clear coat to expand and often separate from the base coat, allowing environmental pollutants to penetrate.
Acids enter the breach formed in the clear coat and attack the resin binder system, which accelerates the degrading of the paint film surface, eventually leading to oxidation and/or failure. Oxidation can appear as a dull and somewhat hazy, or `chalky' appearance to the paint surface, a paint film surface that is adequately protected with wax or a sealant actually has a lower surface temperature than one that is not.
Oxidation (Reduction): [simply means that oxygen is added to a molecule with an electron being displaced, which in turn dries the paint surface].
A sound understanding of the proper technique and the correct process will produce excellent results even with a mediocre product. A quality product used without the proper surface preparation or application technique will never obtain a satisfactory result. Using the proper methodology (surface preparation, using a quality product, along with the correct application technique) will ensure an excellent result.
Skill Level / Experience
Some methods described may be beyond the capabilities of the average detailer or enthusiast; in this case we strongly encourage the reader to consult a professional detailer or body shop concerning the matters discussed herein.
Liability
The writer assumes no responsibility, expressed or implied, due to misuse or misinterpretation of the information or methods used, or for any vehicle damage or injury that may occur due to the suggestions and information offered.
Product Quality and Technique
Proceed with this in mind; the products you use constitute a very small factor in the equation. Methodology and technique constitute 95%; the reasoning behind the choice of quality products is to eliminate any limiting factors, thus enabling you to place emphasis on technique used.
Thickness - a clear coat has a thickness of 1.5 – 2.0 Mils, removing more that 0.4 mil (0.0004") of clear coat will cause premature paint film failure. As a point of reference two sheets of Saran wrap placed on top of each other measure 1.5Mil (0.0015") a surface scratch that will `catch' your fingernail is approximately 0.004" deep and will usually require wet sanding and refinishing. Moderate to light polishing will remove approximately 0.025 Mil of paint. There comes a point when you must judge wither removing a scratch will compromise the clear coat and if so you’ll have to ‘live’ with the imperfection
Ultra Violet Radiation
Clear coat paint (polyurethane) provides the colour and base coats with protection, and usually has UVR 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) once this is gone there is no UVR protection for the basecoat and this will cause clear coat failure (oxidation) and photo degradation (fading) of the colour coat
Water-based paint is very porous, the paint film surface on a microscopic level has many surface imperfections, and is convoluted (a series of peaks and valleys) with time and use, plus normal wear and tear, the surface becomes more permeable, thus allowing ingress. High solid clear coat during the first couple of months, following factory painting will allow moisture to enter the clear and become trapped. This is most noticeable in vehicles that are transported, using transit wrap, when the surface has some moisture and the wrap is placed over it.
On average, a high solid clear coat will absorb approximately one pint of water when the vehicle is subjected to a heavy rain or a car wash. If there is a "clouding" of the clear, simply applying isopropyl alcohol (IPA) to the area, allowing it to dwell and with a heat gun or hair dryer, heat the area (do not exceeding 100.oF spot temperature) The IPA acts as a "drying" agent, and when combined with the heat the moisture will evaporate.
The rate of environmental exposure that negatively affects (clear coat) paint varies widely, but experience shows that 0.0005 –inch (12.7 Microns) 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) Using a moderate to light polish; and utilizing a rotary polisher will remove approximately 0.000025 - inches (0.635 Microns) from the paint surface (they are many variables such as polish/compound and speed / pressure used that may affect the paint removed)
Clear coat paint (polyurethane) provides the colour and base coats with protection, and usually has UVR 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)
Detailing clay has made a huge impact in paint finish care because it removes oxidation and allows the paint to remain healthy, longer. Applying a coating over a paint finish does not stop oxidation; it only slows it down. Waxes with cleaners are better for your paint finish than those without; because they strip away some oxidation and allow the coating to obtain a better hold (anchoring to the micro-fissures of the surface) and lasting longer to retard oxidation. Those of us who properly prep the paint finish prior to waxing do not need these cleaners, but they still help.
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. Oxidation is caused by environmental pollutants (acid rain, ozone, industrial pollutants, hydrocarbons, etc) the suns heat, which also causes paint colour fading from ultraviolet radiation (UVR) inclement weather or the use of harsh detergents, all of which attack the paints binder system(resin)
It starts as a chemical reaction that causes the resin binder system to overheat and dry out, leaving microscopic surface imperfections and micro fissures in the paint film surface that are vulnerable to deterioration. Once the air borne contaminates and pollution compromises the paint surface they accelerate the oxidation (reduction) or paint failure process.
Two- stage paint system- (base, colour and clear coat) - a clear-coat finish does not oxidize in the true sense of the word; meaning that the pigments and resins mix together and the pigments are exposed to the sun's ultra-violet rays, which causes them to dry out or oxidize. The clear coat is applied to protect against this but the finish will become ‘dull’ by using harsh (abrasive) or if acidic car washing solutions as used in ‘touch less’ car washing systems, or from industrial airborne pollutants compromising the clear coat allowing the suns heat to dry out (oxidize) the paint.
The clear coat layer is extremely thin (1.5 – 2.0 Mils) it is not a solid coating and is to some extent porous, oxygen interacts with substances in the paint layer (i.e. mica flakes as in metallic paints) and trigger the oxidation reaction. It's just that the amount of oxidation taking place is minimal in comparison to single stage paint.
For oxidized paint try the following;
•Wash the paint surface and dry thoroughly
•Clean the paint with chemical paint cleaner (Klasse All-In-One) using an orange foam pad at speed #4, this may take 2-3 applications
•Once the oxidation has been removed use a decontamination system (Auto International A B C System (Automotive International - Valugard Product Line)
•Apply an oil rich product to stabilize the paints binder system (3M Imperial Hand Glaze) apply a thick coat and allow to dwell for 12-24 hours before buffing, repeat as necessary until surface has an ‘oily’ sheen.
•Remove residue and apply a Carnauba wax (Zymol Concourse)
•Try to keep vehicle paint surface away from UV heat radiation
•Keep paint surface waxed on a regular basis.
Single-stage paint systems (base and colour coat) – (note-single stage paint is usually very ‘soft’) without a clear coat to provide protection, primarily a hostile environment will attack the paint surface causing microscopic gaps and valleys (micro fissures) and it becomes compromised both chemically; by industrial fallout (IFO) acid rain, brake /rail dust and etc., and by UV heat radiation, which causes it to dry out and/or fail, causing the clear coat to expand and often separate from the base coat, allowing environmental pollutants to penetrate.
Acids enter the breach formed in the clear coat and attack the resin binder system, which accelerates the degrading of the paint film surface, eventually leading to oxidation and/or failure. Oxidation can appear as a dull and somewhat hazy, or `chalky' appearance to the paint surface, a paint film surface that is adequately protected with wax or a sealant actually has a lower surface temperature than one that is not.