AATCC 16:2004 pdf download.Colorfastness to Light
3. Terminology
3.1 AATCC Blue Wool Lightfastness Standard, n.- one of a group of dyed wool fabrics distributed by AATCC for use in determining the amount of light exposure of specimens during lightfast- ness testing (sce 32.1).
3.2 AATCC Fading Unit (AFU), n.- a specific amount of exposure made un- der the conditions specified in various test methods where one AFU is one- twentieth (1/20) of the light-on exposure required to produce a color change equal to Step 4 on the Gray Scale for Color Change or 1.7土0.3 CIELAB units of color difference on AATCC Blue Wool Lightfastness Standard L4.
3.3 black-panel thermometer, n.- -a temperature measuring device, the sens- ing unit of which is coated with black paint designed to absorb most of the radi- ant energy encountered in lightfastness testing (see 32.2).
3.3.1 This device provides an estima- tion of the maximum temperature a spec- imen may attain during exposure to natu- ral or artificial light. Any deviation from the geometry of this device described in 32.2 may have an influence on the mea- sured temperature.
3.4 black standard thermometer, n.- a temperature measuring device, the sensing unit of which is coated with black material designed to absorb most of the radiant energy encountered in lightfast- ness testing and is thermally insulated by means of a plastic plate (see 32.2).
3.5 broad bandpass radiometer, n.- a relative term applied to radiometers that have a bandpass width of more than 20 nm at 50% of maximum transmittance and can be used to measure irradiance at wavelengths such as 300-400 nm or 300- 800 nm.
3.6 color change, n.- as used in col- orfastness testing, a change in color of any kind whether a change in lightness, hue or chroma or any combination of these, discernible by comparing the test specimen with a corresponding untested specimen.
3.7 colorfastness, n.- -the resistance of a material to change in any of its color characteristics, to transfer of its colo- rant(s) to adjacent materials, or both as a result of exposure of the material to any environment that might be encountered during the processing, testing, storage or use of the material.
3.8 colorfastness to light, n.- -the re- sistance of a material to a change in its color characteristics as a result of expo- sure of the material to sunlight or an arti- ficial light source.AATCC 16 pdf download.