This part of ISO 13468 covers the determination of the total luminous transmittance, in the visible region of the spectrum, of planar transparent and substantially colourless plastics, using a Single-beam photometer with a specified CIE Standard light Source and
photodetector. This part of ISO 13468 cannot be used for plastics which contain fluorescent materials. This part of ISO 13468 is applicable to transparent moulding materials, films and sheets not exceeding 1O mm in thickness.
NOTES
1 Total luminous transmittance can also be determined by a double-beam spectrophotometer as in part 2 of the standard. Part 1, however, provides a simple but precise, practical and quick determination. This method is suitable for use not only for analytical purposes but also for quality control.
2 Substantially colourless plastics include those which are
faintly tinted.
3 Spetimens more than 10 mm thick may be measured provided the instrument tan accommodate them, but the results may not be comparable with those obtained using specimens less than 10 mm thick.
Dieser Teil der Norm deckt die Bestimmung des totalen Lichttransmissionsgrades von ebenen transparenten und weitgehend farblosen Kunststoffen für sichtbares Licht ab, indem ein Fotometer verwendet wird, das eine definierte Lichtquelle und einen Lichtsensor gemäß CIE Norm enthält. Diese Norm darf nicht für Kunststoffe verwendet werden, die fluoreszierende Materialien enthalten. Die zu prüfenden Kunststoffe sind typischerweise transparente Formmassen, Folien, Platten und Tafeln mit Dicken kleiner als 10 mm.