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GF98.00-U-9500-11A Paint Scratches From Car Washes (Argumentation Aids)



GF98.00-U-9500-11A Paint Scratches From Car Washes (argumentation Aids)

Automotive paintwork (non-metallic or metallic) is subject to high wear in normal day to day use, due to the extreme effects present today. In spite of the high resistance values of our paint materials, a layer of dirt accumulating under pressure and at high speed results in material abrasion, the degree depending on the type or hardness of the contamination particles.

However, this abrasion differs highly depending on the surfaces in question and results in fine "scoring/scratches" on the paint surface, which are easily visible on medium to dark colors. This gives the impression of a higher sensitivity, which is not the case.

Considering the fact that limits are reached very quickly when we attempt to increase the hardness of organic finishes because of the organic nature of the binding agent and for other reasons it is necessary for the finish to have a certain elasticity, it is obvious that scratches will result as a matter of course in car washes when mineral contamination such as sand - i.e. quartz or feldspar with a hardness of 7 or 6 act on the finish with corresponding pressure. Here the force exerted on the grain of sand by a sponge when washing by hand, or by a brush in a car wash is sufficient to cause abrasion. In consideration of the hardness range of passenger car finishes it is therefore only possible to wash the vehicle without scratching when the mineral particles capable of scratching are removed from the paint before they are caught in the sponge or brush. In the absence of contamination capable of creating scratches, scratches will not occur in a car wash.

The brushes typically consist of an organic material with a hardness similar to that of the organic paint finish.
For this reason brushes do not scratch without contamination.