ASTM E Calculating Yellowness and Whiteness Indices from Instrumentally. Measured Color Coordinates. This practice provides numbers that correlate. Yellowness indices are used chiefly to measure these types of degradation. Yellowness Index per ASTM Method E is calculated as follows. To begin the ASTM D is a now obsolete Yellowness Index specification that is locked to calculate only using C/2 (illuminant C, 2deg.
|Country:||Turks & Caicos Islands|
|Published (Last):||26 March 2004|
|PDF File Size:||20.23 Mb|
|ePub File Size:||9.28 Mb|
|Price:||Free* [*Free Regsitration Required]|
Select enough specimens or specimen areas to provide an average result that is representative of each sample to be tested.
Yellowness Index (YI) ASTM E
Values greater than indicate a bluish white, while values less then indicate a yellowish white. The idea was that chromaticity factor G-B required three times the weighting of the lightness factor G of the lightness. Because visual observing conditions can vary widely, users should compare calculated indices with visual estimates to ensure applicability.
Multiple samples should be measured and the readings averaged.
The greater the illumination intensity in the UV-range, the more the greater the detection of the optical lightener. For whiteness measurement, this practice is limited to specimens having Munsell value greater than 8. Test sample e133, handling, and preparation preferably no cleaning can affect the test results by modifying the surface of the sample.
The effect occurs at approximately nm; maximum radiation is at approximately nm.
Enabling you to identify and mitigate the intrinsic risk in your operations, supply chains and business processes. What is mainly annoying with the one-dimensional white evaluation astmm, that in the same measurement value there is a quality valuation How white is the sample? Historical Version s – view previous versions of standard Translated Version s: Whiteness and Yellowness Indices in a SpectroEye Yellowness Yellowness is defined as a measure of the degree to which ee313 color of a surface is shifted from preferred white or colorless towards yellow.
However, this also intensifies ISO brightness. Historical Version s – view previous versions of standard. Its derivation assumed that, because of the limitation of the concept to yellow or qstm colors, it was necessary to take account of variations in the amber or red colorimeter readings.
Standards can be obtained from appropriate standard authorities.
Auditing Consulting Sourcing Training. Standard illuminant D65 must be used for measurement of optically lightened papers. The optical lightener is effective only due to the UV radiation. In general, specimens should be prepared and presented for measurement in the manner that is standard for the test being performed. The color deviation number Tw e3113 additionally, if there is a red hue qstm value of Tw or a green hue positive value of Tw.
Whiteness and Yellowness Indices in a SpectroEye
Global Reach Intertek is the industry leader with over 42, people in 1, locations 3e13 over countries. After specifying the illuminant, observer angle, and the reference color, the test sample is inserted into the specimen holder, and the spectrophotometer takes the reading. This practice provides recommended equations for such scales and discusses their derivations and uses, and limits to their applicability see also Ref 1 2. Yellowness according to ASTM E D was developed specifically for determining the asstm of homogeneous, non-fluorescent, nearly colorless, transparent, nearly white translucent, or opaque plastics, as viewed under daylight lighting conditions.
Inspection Validating the specifications, value and safety of your raw materials, products and assets. Evaluating how your products and services meet and exceed quality, safety, sustainability and performance standards. Aetm method is based on the use of colorimeter readings B and G.
Testing Evaluating how your products and services meet and exceed quality, safety, sustainability and performance standards.
Send us a request Need help or have a question? It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Referenced Awtm purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard.
Whether your business is local or global, we can ensure your products meet quality, health, environmental, safety, and social accountability standards for virtually any astmm around the world. Some standards addressing the visual estimation of color and color difference are Practices DDEand Eand Guide E However, the equation is commonly used with other illuminants and observer functions, therefore the value shown will depend on the primary illuminant and the observer function you have chosen.