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ASTM D [ Withdrawn ].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 effect asm at approximately nm; maximum radiation is at approximately nm. Professional horizontal design and it does not have any moving parts, which avoids the shaking of the instrument during measurement process. What is mainly annoying with the one-dimensional white d19225 is, that in the same measurement value there is a quality valuation How white is the sample? 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.
Whiteness Whiteness is defined as a measure of how closely a surface matches the properties of a perfect reflecting diffuser, i. This makes the measurement more accurate. Standard ISO specifies a half peak width of 44 nm. Shipped in 10 days after payment. In the case of non s1925 samples, standard illuminant C, i.
For the purposes of this standard, the color of such a surface is known as preferred white. The idea was that chromaticity factor G-B required three times the weighting of the lightness factor G of the lightness. D1952 illuminant D65 must be used for measurement of optically lightened d192.
Yellowness, as defined by ASTM Ehas been applied successfully to a variety of white or near-white materials, including paints, plastics, and textiles. However, the equation is commonly used with other illuminants and observer functions, therefore the value shown will depend d1295 the primary illuminant and the observer function you have chosen.
Allows medium and small companies to obtain high performance color management system with relatively low price. Yellowness according to ASTM E D was 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. Large data storage space: The optical lightener is effective only due to the UV radiation.
ASTM D1925, ASTM E313 Spectrophotometer
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. China spectrophotometer model China price of spectrophotometer China uv vis double beam spectrophotometer. Operation system supports both English and Chinese interfaces, and we offer to design the interface in other languages based on the need of our customers.
However, the equation is commonly used with other illuminants; therefore the value shown will depend on the primary illuminant you have chosen. It can also be applied to materials other than plastic fitting this description. True color screen that includes all colors Work temperature range: Does not include UV light source.
Adding powder test accessories, easily measure the color of the Powder, granules and other samples. China uv spectrophotometer China spectrophotometer cuvette China uv visible spectrophotometer. Contact Supplier Start Order.
PC software for easy measurement data management. Comparable values between two instruments can be obtained only when both are measured with the same light. China spectrophotometer price China digital spectrophotometer China atomic absorption spectrophotometer. 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 or red colorimeter readings.
The ISO brightness value indicates the blue reflection of the paper. Ashm method is based on the use of colorimeter readings B and G.
Yellow Index YI caculation standard E D_图文_百度文库
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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.
It should be clear that the distribution of relative spectral radiation of the light on the sample during measurement plays an important role. The indices can be calculated, rounded, and adjusted in the last retained significant digit to minimize the residual error in the white point values. However, this also intensifies ISO brightness.
Whiteness and Yellowness Indices in a SpectroEye
Size of integrating sphere: Whiteness and Yellowness Indices in a SpectroEye Yellowness Yellowness is defined as a measure of asttm degree to which the color of a surface is shifted from preferred white or colorless towards yellow. Stensby — based on Hunter Lab color coordinates. Values greater than indicate a bluish white, while values less then indicate a yellowish white. It entails a filter with a maximum transmission curve of nm wavelength lambda and a specific half peak width. Not exactly what you want?
The greater the illumination intensity in the UV-range, the more the greater the detection of the optical lightener. The software atm all necessary color equations, standard light sources, and a large number of standards for specific industries and applications.