The Color of Art Pigment Database

“its unique chemical formula is fluorescent which subtly refracts orange under a black light a treat that often coincides with a lack of lightfastness there's very little info about its long-term performance as an art material that's something to keep in mind if your work requires you to be concerned with light vastness but you like to try new rare or exclusive pigments and paint catalogs your art could be where problems begin to be documented even pigments that have been around a while sometimes vary between brands independent artist testing often finds unexpected brand specific problems because companies can just look up a rating from astm a huge testing standards organization regarding previously completed tests to simply copy the results under their paint label there's no rule to prevent a brand from copying test results done 30 years ago regarding the pigment code they're using even if that tested pigment sample was made by a completely different manufacturer also on the subject of labeling unless it's a toxic chemical flagged for special import paint brands aren't even required to fully disclose pigment ingredients this helps companies protect trade secrets but also means there's nothing to keep them from further misrepresenting their products just like the problem i've seen in pr 177 and popular mixtures made with that red like moonglow po64 also fades the most dramatically when diluted this means any color you mix with p064 will likely be even more fugitive than moon glow this video shows lightfast test results from nine months where the watered-down p064 has completely disappeared off the page as if it was never painted normally a color rated as blue wool 7 or 8 would show very little to no signs of fading at this time even the mass tone is showing some damage but the most pigmented thick layer from white nights seems to be the least affected everything i'm seeing indicates that p064 was rated in mastone and not properly diluted some pigment suppliers and the paint makers who buy from them do not seem to follow astm standards for raiding pigments at their most vulnerable acrylics should be mixed with white to achieve pale tints and watercolors are diluted down to pale washes with water astm gives ratings based on the worst performance when diluted not a pigment strength in mass tone i know golden acrylics and core watercolors are tested this way but i'll have to inquire with rembrandt regarding that questionable of 2 rating note it seems like an error as i don't see how you could test p064 diluted and not see a problem in just a few weeks especially if they're using a rooftop or skyward facing box that receives more daylight hours than my vertical window even one directional sunrise or sunset tests show dramatic levels of fading in just a few months unfortunately pigment powder companies around the world can decided lightfast test colorants however they see fit they could use a xenon light machine that simulates outdoor light and is not as intense as tests behind window glass like astm performs in arizona companies can also decide to test different materials than fine art paints they make color plastic for appliances or housewares printed signs or automotive coatings which may not best represent the pigment performance in artist paints yet that rating may end up on a tube of watercolor the most common lightfast rating test used worldwide is called the blue wool scale for this test a panel of eight different dyed cloth strips is placed under direct sunlight near the other colors you're testing the time at which each blue strip starts to fade is how you assign a number rating each one of these blue dies is more uv stable than the next the bottom of the scale blue wool one is the most fugitive dye strip which starts to fade within hours to days if a color you're testing nearby faded just as quickly as bw1 that's its rating as the number gets higher the dies used are more lightfast and take longer to fade blue wool stripes 6 7 and 8 are generally considered light fast for professional art use this was created by the textile industry to measure how fast clothing dies would fade while simple it's not a foolproof test it can be error prone when discerning the dark blue mass tone fading in relation to the fading of lighter value colors the test can be completed too quickly to detect long-term fading issues especially if a pigment fades at a different rate than the blue wool dies colors can also break down more severely in different testing environments such as the presence of humidity or air pollution test duration is complete when the most durable lightfast stripes start to fade the amount of dv that this takes is roughly equivalent to 100 years of museum lighting which is why that time frame is sometimes mentioned in paint catalogs because the dye panel fades based on the amount of uv light it absorbs it's not a time duration test fading varies by season uv intensity heat and humidity in your area this test can be completed in as short as three to four months in the summer but tests can take 9 to 12 in lower uv index northern climates or winter months home tests and vertical windows take longer than sky facing or angled box tests the amount of hours you get in direct light is less per day and too many rainy days also affect this time if you're testing at home without a blue wool reference panel know that life s colors can typically be exposed to over a year of direct sunlight without notable color change a full year is a good time duration goal if testing colors with different start dates that way they all receive different seasons of uv strength for a fair comparison many colors don't initially appear to fade in under six months but can drastically fade at different rates over the next six if you see something start to fade in just a few months it's probably really fugitive p064 started showing signs of fading within four weeks right around the same time as my blue wool number three to four strips were fading astm evaluates blue wool in a gray scale and assigns numbers in the opposite numerical order as roman numerals one through five one being the most lightfast five being fugitive if you're not interested in doing light fast testing yourself but you wanna feel confident in your paints the easiest solution is to stick with the tried and true basics there are a lot of reliable pigments that have been around for long enough that artists have thoroughly tested them for you there's no need to feel limited either there's plenty of options you can even replicate unique looking mixtures like daniel smith's moon glow and primatech colors if you're willing to do some color mixing there's some great resources online for setting up a light fast palette starting with primary mixing basics hand prints website has a top 40 pigment list the color of art pigment database allows you to check any pigment code number for problems or fading notes and i pretty regularly add web webpages to kimcrike”