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Tempered Glass - Spotting/Mottled Appearance

83ford10

Article No. 83-16-4


GLASS - MOTTLING IN TEMPERED GLASS


FORD ALL CARS

LINCOLN-MERCURY ALL CARS

LIGHT TRUCKS ALL TRUCKS

MEDIUM/HEAVY TRUCKS ALL TRUCKS

To assist with customer concerns about spots in the glass on cars and trucks, the following information is being published.

MOTTLING IN TEMPERED GLASS (All Car/Truck Lines - All Models The small, faint, somewhat lustrous, grayish and fairly geometric spots detected in side and rear window tempered glass is characteristic of tempered glass and is considered within the design limits of this type of glass. This mottling condition is noted under selected conditions of lighting and is seemingly aggravated by the use of curved side window glass. The boldness of the mottled pattern in a given glass will be variable, depending largely upon the conditions of illumination and will appear intensified if viewed through Polaroid sun glasses.

This unusual occurrence of mottling does not affect the quality of the glass and cannot be reduced by scouring the glass surface.

Mottling is caused by the polarized properties of natural light which result from the effects of atmospheric dust and other angular reflections. This polarization in combination with the light polarizing properties that are unavoidably imparted to tempered glass is a consequence of the forces of locked-in tension and compression which make tempered glass so remarkably strong. For these reasons, this condition will never be seen in laminated glass.
If complaints of side window mottling are encountered, it should be explained to the customer that this condition is natural and unavoidable, and under no condition is the replacement of glass warranted or effective.

OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: "INFORMATION ONLY"