Technical Info on Colorants

Where to learn about 844 colorants, "universal" tints, et cetera. October 15, 2009

Question
I recently had to redo a glazed CV finish because I added a universal color I had to some MLC glaze base. The finish delaminated a week later. After I read the tech sheet I realized I should have used a Hul 844 colorant. I realized that I am completely ignorant of the Hul terminology. I think that the Degussa Co. makes these, and Hul is a trade name, not a generic term. Is this correct? And what exactly is a universal colorant? Does it have a number like the 844 or 866?

Forum Responses
(Finishing Forum)
From contributor J:
Huls company sold their lineup many years ago to Degussa, which recently sold to Evonik. But the numbering system started by Huls carried over with numbers like 844, 896, 830, 864, etc. These numbers are still used. 844 and other colorants are binder specific, meaning they are compatible with specific binders, such as solvent based lacquers and acrylics (844) or waterborne products (896).

Universal colorants were developed for the paint stores so they could use one colorant to tint both waterbornes and oil based paints. That way they could use one tint machine for both bases. You can buy universal colorants under the name old Cal-Tint 830 (now Evonik), Tints-All, etc.

The problem with a universal colorant is that it has to be made with a rather high amount of surfactants and dispersion aids so that they are compatible with both solvent and water systems. These products generally do not evaporate so they remain in the finish and issues can arise such as softness and adhesion. Universal colorants are okay as long as you are using small amounts to adjust color only. They shouldn't be used in larger amounts (like 5%).

That's why industrial formulators like Sherwin Williams and MLC recommend the colorant specific 844 (or others) for their products.



From contributor W:
Is there a central place that has an explanation of each colorant type, and hopefully technical data on them?


From contributor D:
So what is the big difference between 844's and 866's? I have used both and don't see much difference except in colors and maybe tinting strength.


From contributor J:
844's are dispersed in a solvent acrylic binder. The 866's are in a fast drying alkyd base. To a certain extent, there would be some overlapping in applications (like cellulose lacquers), but my recollection is that the 866's are used in things like baking enamels and silicones, areas where the 844's might be a problem. The 844 white also would have better color retention (less prone to yellowing) in a situation where that would be a problem. I also see that 844's tend to be more available to the small shop user. I used to be able to get quarts from my Sherwin Williams Commercial branch.

Because these are industrial colorants, there really isn't a data bank - trained reps usually market them to paint companies and such. There is some info if you go to the Evonik website.