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ASTM D [ Withdrawn ].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.

Author: Shakazil Mezicage
Country: Slovenia
Language: English (Spanish)
Genre: Literature
Published (Last): 7 November 2013
Pages: 320
PDF File Size: 12.50 Mb
ePub File Size: 15.66 Mb
ISBN: 723-7-98275-322-5
Downloads: 40047
Price: Free* [*Free Regsitration Required]
Uploader: Zulkit

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. This makes the measurement more accurate.

Whiteness and Yellowness Indices in a SpectroEye

Comparable values between two instruments can be obtained only when both are measured with the same light. The effect occurs at approximately nm; maximum radiation is at approximately nm.

Contact Supplier Start Order. However, the equation is commonly used with other illuminants; therefore the value shown will depend on the primary illuminant you have chosen.

ASTM D – 70() Test Method for Yellowness Index of Plastics (Withdrawn )

Global Gateway Please select your desired language. 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. 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. Jinan Xinghua Instruments Co.

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. Size of integrating sphere: China spectrophotometer model China price of spectrophotometer China uv vis double beam 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.

  BRIGO MERCURIO INTEREST RATE MODELS PDF

Professional horizontal design and it does not have any moving parts, which avoids the shaking of the instrument during measurement process. In the case of non lightened samples, standard illuminant C, i. The software contains all necessary color equations, standard light sources, and a large number of standards for specific industries and applications. China uv spectrophotometer China spectrophotometer cuvette China uv visible spectrophotometer.

Standard ISO specifies a half peak width of 44 nm. The optical lightener is effective only due to the UV radiation.

ASTM D1925, ASTM E313 Spectrophotometer

Shipped in 10 days after payment. Does not include UV light source. Standard illuminant D65 must be used for measurement of optically lightened papers. True color screen that includes all colors Work temperature range: Large data storage space: The idea was that chromaticity factor G-B required three times the weighting of the lightness factor G of the lightness.

PC software for easy measurement data management. It can also be d1295 to materials other than plastic fitting this description. 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. It entails a filter with a maximum transmission curve of nm wavelength lambda and a specific half peak width.

Xstm design, powerful instrument functions Professional horizontal design and it does not have any moving parts, which avoids the shaking of the v1925 during measurement process. Not exactly what you want? Adding powder test accessories, easily measure the color 1d925 the Powder, granules and other samples.

  COMPUTER NETWORKS AND INTERNETS COMER PDF

Values greater than indicate a bluish white, while values less then indicate a yellowish white. Stensby — based on Hunter Lab color coordinates. China spectrophotometer price China digital spectrophotometer China atomic absorption spectrophotometer.

Yellowness, as defined by ASTM Ehas been applied successfully to a variety asmt white or near-white materials, including paints, plastics, and textiles.

The indices can be calculated, rounded, and adjusted in the last retained significant digit to minimize the residual error in the d19925 point values. For the purposes of this standard, the color of such a surface is known as preferred white.

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? However, this also intensifies ISO brightness. Whiteness and Yellowness Indices in a SpectroEye Yellowness Yellowness is defined as a measure of the degree to which the color of a surface is shifted from preferred white or colorless towards yellow.

This method is based on the use of colorimeter readings B and D125. The ISO brightness value indicates the blue reflection of the paper.

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. Whiteness Whiteness is defined as a measure of how closely a surface matches the properties of a perfect reflecting diffuser, i. It should be clear that the distribution of relative spectral radiation of the light on the sample during measurement plays an important role.