ASTM D1925 PDF

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ASTM D [ Withdrawn ].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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ASTM D1925, ASTM E313 Spectrophotometer

Operation v1925 supports both English and Chinese interfaces, and we offer to design the interface in other languages based on the need of our customers. China spectrophotometer price China digital spectrophotometer China atomic absorption spectrophotometer.

This makes the measurement more accurate. The software contains all necessary color equations, standard light sources, and a large number of standards for specific industries and applications. 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.

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? 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. Comparable values between two instruments can be obtained only when both are measured with the same light.

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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. The indices can be calculated, rounded, and adjusted in the last retained significant digit to minimize the residual error in the white point values.

It entails a filter with a maximum transmission curve of nm wavelength lambda and a specific half peak width. The effect occurs at approximately nm; maximum radiation is at approximately nm. The greater the illumination intensity in the UV-range, the more the greater the detection of the optical lightener. Does not include UV light source. For the purposes of this standard, the color of such a surface is known as preferred white.

Values greater than indicate a bluish white, while values less then indicate a yellowish white. It can also be applied to materials other than plastic fitting this description. 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.

However, this also intensifies ISO brightness. Adding powder test accessories, easily measure the color of the Powder, granules and other samples.

ASTM-D | Test Method for Yellowness Index of Plastics (Withdrawn ) | Document Center, Inc.

Yellowness, as defined asfm ASTM Ehas been applied successfully to a variety of white or near-white materials, including paints, plastics, and textiles. In the case of non lightened samples, standard illuminant C, i.

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Size of integrating sphere: Large data storage space: True color screen that includes all colors Work temperature range: This method is based on the use of colorimeter readings B and G. China uv spectrophotometer China spectrophotometer cuvette China uv visible spectrophotometer.

ASTM D – 70() Test Method for Yellowness Index of Plastics (Withdrawn )

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 optical lightener is effective only due to the UV radiation.

CIE Whiteness — Some disadvantages of the previously-mentioned indices is that a whiteness that d1952 calculated with this formula does not differ if the measured sample has a color drift or is just less white.

Shipped in 10 days after payment. PC software for easy measurement data management.

Not exactly what you want? Jinan Xinghua Instruments Co. The idea was that chromaticity factor G-B required three times the weighting of the lightness factor G of the lightness.