ASTM D1925 PDF
ASTM D [ Withdrawn ]. Standard Test Method for Yellowness Index of Plastics. standard by ASTM International, 01/22/ View all. wnessIndex was developed for the definition of the Yellowness of homogeneous, non-fluorescent, almost. Yellowness – ASTM D A measure of the yellowing of a plastic, such as might occur after long-term exposure to light. The deviation in chroma from.
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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 idea was that chromaticity factor G-B required three times the weighting of the lightness factor G of the lightness. Yellowness, as defined by ASTM Ehas been applied successfully to a variety of white or near-white materials, including paints, ashm, and textiles.
Whiteness and Yellowness Indices in a SpectroEye
Zstm not include UV light source. The color deviation number Tw shows additionally, if there is a red hue negative value of Tw or a green hue positive value of Tw. However, the equation is commonly dd1925 with other illuminants; therefore the value shown will depend on the primary illuminant you have chosen.
This method is based on the use of colorimeter readings B and G. China spectrophotometer price China digital spectrophotometer China atomic absorption spectrophotometer.
Yellow Index YI caculation standard E D_图文_百度文库
Comparable values between two instruments can be asm only when both are measured with the same light. 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? Large data storage space: The software contains all necessary color equations, standard light sources, and a large number of standards for specific industries and applications.
It should be clear that the distribution of relative spectral radiation of the light on the sample during measurement plays an important role. CIE Whiteness — Some disadvantages of the previously-mentioned indices is that a whiteness that is calculated with this formula does not differ if the measured sample has a color drift or is just less white.
In the case of non lightened samples, standard illuminant C, i. Operation system supports both English and Chinese interfaces, and we offer to design the interface in other d195 based on the need of our customers.
Not exactly what you want? PC software for easy measurement data management. Whiteness and Yellowness Indices in d19255 SpectroEye Yellowness Yellowness is defined as a measure of dd1925 degree to which the color of a surface is shifted from preferred white or colorless towards yellow.
China spectrophotometer model China price of spectrophotometer China uv vis double beam spectrophotometer. The effect occurs at approximately nm; maximum radiation is at approximately nm. Size of integrating sphere: Allows medium and small companies to obtain high performance color management system with relatively low price.
The greater the illumination intensity in the UV-range, the more the greater the detection of the optical lightener. The optical lightener is effective only due to the UV radiation. Yellowness according to ASTM E D d11925 developed specifically for determining the yellowness of homogeneous, non-fluorescent, nearly colorless, transparent, nearly white translucent, or opaque plastics, as viewed under daylight lighting conditions.
China uv spectrophotometer China spectrophotometer cuvette China uv visible spectrophotometer. 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.
ASTM D1925, ASTM E313 Spectrophotometer
The ISO brightness value indicates the blue zstm of the paper. This makes the measurement more accurate. Standard illuminant D65 must be used for measurement of optically lightened papers. Jinan Xinghua Instruments Co.
Values greater than indicate a bluish white, while values less then indicate a yellowish white. Whiteness Whiteness is defined as a measure of how closely a surface matches the properties of a perfect reflecting diffuser, i.
Its derivation assumed that, because of the limitation of the concept to yellow or blue colors, it was necessary to take account of variations in the amber c1925 red colorimeter readings. Standard ISO specifies a half peak width of 44 nm. True color screen that includes all colors Work temperature range: Global Gateway Please select your desired language. Shipped in 10 days after payment. Professional horizontal design and it does not have any moving parts, which avoids the shaking of the instrument during measurement process.
It can also be applied to materials other than plastic fitting this description. It entails a filter with a maximum transmission curve of nm wavelength lambda and a specific half peak width. Professional design, powerful instrument functions Professional horizontal design and it does not have any moving parts, which avoids the shaking of the instrument during measurement process. For the purposes of this standard, the color of such a surface is known as preferred white.
Contact Supplier Start Order. Stensby — based on Hunter Lab 1d925 coordinates. However, this also intensifies ISO brightness. Adding powder test accessories, easily measure the color of the Powder, granules and other samples.