“Carbon black, also called charcoal black lamp black, pigment black, soot or black carbon, is a fine particle carbon pigment obtained as soot from the incomplete combustion of many different types of organic materials, such as natural gas, or oil. Carbon black is usually a fine, soft, black powder. It is very stable and unaffected by light, acids and alkalis. It is commonly used in printing and lithograph inks and in Chinese ink sticks. In industry, carbon black is used as a filtration material and a filler /pigment in coatings, rubber, plastics, paints, carbon paper, and crayons. Continue reading
As described in Section 6 of ASTM D1209, there are 2 criteria to validate a APHA/Pt-Co 500 standard: Continue reading
FAQ:”A client is asking me to measure something they call “Molten Color’. Do you have any information on this? Do Hunterlab instrument have a function for this color?” Continue reading
HunterLab diffuse sphere instruments are often used to measure liquid samples, especially clear liquids. The liquid fragrance shown above is one such example of a clear liquid. The fragrances is so clear that is resembles water.
Fragrances such as this are often added to cleaning supplies, air fresheners, or other consumer products. One of the problems that this type of sample can experience is that the chemistry of the liquid fragrance solution can deteriorate and the solution will start to visually yellow. This is often a concern for manufactures because if the liquid fragrance yellows it cannot be added to the end product.
HunterLab sphere instruments can measure the transmitted color of the liquid and report the yellowness index. The liquid fragrance should be measured in a 20mm path length cell. Since the sample is very clear, near water in color, this slightly larger path length allows for the light to pass through more of the sample. This measurement method ensures that smaller differences can be measured between samples.
With the proper instrument and the appropriate accessories from HunterLab, very clear liquid samples can be accurately and repeatedly measured for color consistency.
HunterLab sphere instruments with CIE d/8 geometries conform to the requirements of ASTM D1003 Section 8: Procedure B Spectrophotometer. The measurement of transmission haze using Procedure B instruments will be in close agreement with ASTM D1003 Procedure A Haze meter.
Here is a more detailed description of how the HunterLab UltraScan PRO, UltraScan VIS and ColorQuest XE meet the requirements of Section 8.
FAQ: “We have a scientist here who is looking at films containing small bubbles and attempting to do measure them by measuring Haze% on a HunterLab spectrophotometer. I suspect her problem in obtaining numbers that “make sense” from what you get from just eyeballing the samples (and trying to look through them at the outlines of a object behind the film to gage the amount of regular transmittance) is that her samples have Haze% > 30 %, which means that a spectrophotometer (or even a haze meter) isn’t the appropriate tool to use for the analysis.
How is transmission haze measured at levels > 30%?”
One application that often comes up is measuring the color of clean liquids such as the fragrance sample seen above. This liquid fragrances is clear and looks almost like water. Fragrances such as this are often added to cleaning supplies, air fresheners, or other consumer products. One of the problems that this type of sample can experience is that the chemistry of the liquid fragrance solution can go bad and it will start to visually yellow. This is a concern of the manufacture because if the liquid fragrance yellows it cannot be added to the end product. Continue reading