GF98.00-U-9100-01A Chemical Effects on Paintwork

GF98.00-U-9100-01A Chemical Effects On Paintwork


Chemical effects on paintwork
The finish on vehicles from painting serves aesthetic purposes as well as protection against external effects which can lead to visible damage or destruction to the vehicle.
However, even the highest quality vehicle finishes, which certainly includes the paintwork on Mercedes-Benz vehicles, cannot be completely insensitive or resistant to all external effects. This applies regardless of the brand of paint, the mixture and color, for physical effects such as stone impact, washing scratches, UV radiation, the effects of temperature and attack by chemical substances. Aggressive substances include precipitation combined with residues from oil burning systems, pesticides, building protection products, cement dust, chemicals and solvents as well as secretions from certain types of plants and droppings from birds and insects.
The attack on organic coatings can be extreme, due to the extremely aggressive acids or alkaline solutions combined with dissolving substances or biochemical decomposition reactions.

The extreme alkali character of certain washing agents in automatic car washes can also cause surface disintegration (chemical decomposition) due to saponification of the binding agent. This then makes the paint finish sensitive to attack from other paint damaging substances.
The majority of the types of possible paint damage are well known to paint manufacturers and users. The study of the interrelationships with the objective of developing systems with higher resistance is not a new endeavor. However, for the resistance to chemicals, the chemical composition of the binding agent and pigments is the primary factor, not the hardness.

The paints used today as well as all newly developed pigments are based on resins with functional ester, ether, amine or urethane groups capable of chemical decomposition (saponification) under the above conditions.
Factors affecting the rate of finish decomposition are primarily the temperature, humidity (frequently alternating), concentration and effective time in relation to the damaging mechanism. For this reason soiling, droppings, etc. should be removed immediately.

Determination of the causes of damage is frequently difficult because the damaging substances are no longer detectable even with the use of expensive modern analytical methods. This damage which can be in the form of spots, discoloration, softening, etching or flaking, is frequently considered by clients to be the result of poor paint quality or production deficiencies such as insufficient hardness.

Finally, it should be mentioned that Mercedes-Benz cooperates with paint manufacturers and research institutes in performing comprehensive studies on the causes and possibilities for developing and introducing paint systems which provide greater resistance and use benefits.