Verkkokauppa
SFS-EN 13523-3:2024:en
Coil coated metals. Test methods. Part 3: Colour difference and metamerism. Instrumental comparison
Soveltamisala
Suomenkielistä soveltamisalaa ei ole saatavissa.
This document specifies procedures for determining the instrumental colour difference (CIELAB or ) of an organic coating on a metallic substrate compared to another one used as a reference (usually called reference) and the metamerism depending on the illuminant.
When two colour specimens have identical spectral reflectance curves, they are matching under any illuminant irrespective of its spectral characteristics. This is termed a “spectral match”. It is also possible for two colour specimens having different spectral reflectance curves to match visually under a given light source but not to match under another light source with different spectral characteristics; such matches are termed "metameric".
One quantitative description of metamerism is the so-called "metamerism index".
Information on the metamerism index is of limited value where ?E (instrumental colour difference for a given illuminant) is > 0,5. The metamerism index is not suited for determining the absolute colour difference or colour consistency of a given specimen at change of illuminant.
The colour difference under the reference illuminant is to be measured in colour coordinates L*, a* and b*.
Excluded from this method are organic coatings producing fluorescence and/or which are multicoloured, pearlescent or metallic.
Establishing a reference as well as the magnitude of an acceptable colour difference are not covered by this method.
Two methods are given in this document:
a) instrumental colour difference measurement using a tristimulus colourimeter;
b) instrumental colour difference measurement using a spectrophotometer or equivalent.
It is advised that care is taken when measuring e.g.
- textured surfaces;
- fluorescent coatings;
- metameric coatings;
- multi-coloured, pearlescent, metallic or special colour effect coatings.
Tämän julkaisun valmistelusta Suomessa vastaa Kemesta ry, puh. 040 820 4888.
This document specifies procedures for determining the instrumental colour difference (CIELAB or ) of an organic coating on a metallic substrate compared to another one used as a reference (usually called reference) and the metamerism depending on the illuminant.
When two colour specimens have identical spectral reflectance curves, they are matching under any illuminant irrespective of its spectral characteristics. This is termed a “spectral match”. It is also possible for two colour specimens having different spectral reflectance curves to match visually under a given light source but not to match under another light source with different spectral characteristics; such matches are termed "metameric".
One quantitative description of metamerism is the so-called "metamerism index".
Information on the metamerism index is of limited value where ?E (instrumental colour difference for a given illuminant) is > 0,5. The metamerism index is not suited for determining the absolute colour difference or colour consistency of a given specimen at change of illuminant.
The colour difference under the reference illuminant is to be measured in colour coordinates L*, a* and b*.
Excluded from this method are organic coatings producing fluorescence and/or which are multicoloured, pearlescent or metallic.
Establishing a reference as well as the magnitude of an acceptable colour difference are not covered by this method.
Two methods are given in this document:
a) instrumental colour difference measurement using a tristimulus colourimeter;
b) instrumental colour difference measurement using a spectrophotometer or equivalent.
It is advised that care is taken when measuring e.g.
- textured surfaces;
- fluorescent coatings;
- metameric coatings;
- multi-coloured, pearlescent, metallic or special colour effect coatings.
Tämän julkaisun valmistelusta Suomessa vastaa Kemesta ry, puh. 040 820 4888.
Tuoteryhmä(t)
Sidokset
Velvoittavat viittaukset
Tekninen komitea
Vahvistuspäivä
03.05.2024
Julkaisupäivä
07.05.2024
Painos
4
Sivumäärä
13
Julkaisun kieli
englanti