> Oberflächenbeschädigungen

Mechanical damage

Scratches can vary in intensity and cause:

Angel hair scratches
Extremely fine scratches which cannot
be determined by touch and are hardly
visible in daylight.
Fine scratches
Light scratches visible against a darker background or after close inspection.
Cannot be detected by a fingernail.
Light scratches
These can be detected by a fingernail
and are visible in a certain light.
Deep scratches
Easily visible at any angle and against any background. Whitish in colour.
Easily felt with a fingernail.
Scrapes
These are made up of many light and
deep scratches and have a whitish colour.

Chemical burn, opaque spots and other damage, usually caused by superalkaline cleaner, hydroflouric acid, hydrogenfloride:

Chemical burn
Usually the result of alkaline cleaners.
Cement burn
Result of rain splashes from various forms
of cement.
Hydrofluoric acid
It is well known that this causes burn
marks on glass and it is an ingredient
of most glass cleaners.
Limewash
Limewash attacks any alkali and lime
in the glass leading to surface damage
and visible residue.
Waterglass
Sodium silicate together with potassium silicate is sometimes used in glue for
posters or as a binding medium in paint.
Sealer
Quite often sealing products containing
silicic acid are used on weather-beaten
stone building fronts or facades.
Impregnation
and preservation
mpregnating agent and preservation material containing saline, siloxane and
other thinning agents are often used to
impregnate metal and stone building fronts.