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.
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Send us a request Need help astk have a question? For near-white specimens, however, it is often useful to calculate single-number scales of yellowness or whiteness. Formally confirming that your products and services meet all trusted external and internal standards. The indices can be calculated, rounded, and adjusted in the last retained significant digit to minimize the residual error in the white point values.
The effect occurs at approximately nm; maximum radiation is at approximately nm. For whiteness measurement, this practice is limited to specimens having Munsell value greater than 8.
Whiteness and Yellowness Indices in a SpectroEye
Inspection Validating the specifications, value and safety of sstm raw materials, products and assets. Whether your business is local or global, we can ensure your products meet quality, health, environmental, safety, and social accountability standards for virtually any market around the world.
What is mainly annoying with the one-dimensional white evaluation is, that in the same measurement value there is a quality valuation How white is the sample? This practice provides recommended equations aatm such scales and discusses their derivations and uses, and limits to their applicability see also Ref 1 2. Stensby — based on Hunter Lab color coordinates. The greater the illumination intensity in the UV-range, the more the greater the detection of the optical lightener.
Historical Version s – view previous versions of standard Translated Version s: Certification Formally confirming that your products and services meet all trusted external and internal standards.
No other units of measurement are included in this standard. Through our network of over 43, people in 1, laboratories and offices in countries, Intertek provides quality and safety solutions to a wide range of industries around the world. Enabling you to identify and mitigate the intrinsic risk in your operations, supply chains and business processes. Select enough specimens or specimen areas to provide an average result that is representative of each sample to be tested.
The ISO brightness value indicates the blue reflection of the paper. For the purposes of this standard, the color of such a surface is known as preferred white.
It can also be applied to materials other than plastic fitting this description.
Yellowness Index (YI) ASTM E
The optical lightener is effective only due to the UV radiation. It entails a filter with a maximum transmission curve of nm wavelength lambda and a specific half peak width. Multiple samples should be measured and the readings averaged. Test sample packaging, handling, and preparation preferably no cleaning can affect the test e3113 by modifying the surface atsm the sample.
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.
Whiteness Whiteness is defined as a measure of how closely a surface matches the properties of a perfect reflecting diffuser, i.
Yellowness Index is a number calculated zstm spectrophotometric data that describes the change in color of a test sample from clear or white to yellow.
In the case of non lightened samples, standard illuminant C, i. 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.
Yellowness Index (YI) ASTM E313
Since YI testing is often a series of comparative measurements over extended periods of time, these factors should be defined and documented prior to any testing. This test is most commonly used to evaluate color changes in a material caused by real or simulated outdoor exposure. However, this also intensifies ISO brightness.
Global Reach Intertek is the industry leader with over 42, people in 1, locations in over countries. It should be clear that the distribution of relative spectral radiation of the light on the sample during measurement plays an important role.