ATM Source: Anodizing Dyes

[David Sleeter <sleete19@idt.net>]

Hi Folks:

For the past few days I've been researching the availability of dyes for 
anodizing aluminum, and here's what I've learned.

A popular source within the industry is the Clariant Corporation, 4000 
Monroe Rd., Charlotte, NC 28205, phone: (704) 331-7000. They carry every 
color you could ever need including several shades of black. Anodizing 
dyes come in several types that vary in price depending on what they are 
made of and their intended application. As I'm sure you know, some dyes 
fade when exposed to sunlight and some don't. The ones that don't are 
called "lightfast" and cost a little more.

Because telescopes often sit out in the sun, for black 
anodizing, Clariant's technical department recommends their lightfast 
"Deep black MLW Powder" specifically designed for exterior aluminum 
architectural work. This is the blackest black that they make. Their 
minimum order is 1 lb., and a one pound package costs $64.11. They say to 
mix it with deionized (distilled) water in a concentration of 10 grams of 
dye powder to 1 liter of water, so a one pound package will make about 11 
gallons of dye solution. They offer small price breaks for larger orders; 
i.e. $54.11/lb. if you buy 5 to 24 lbs. For $25 they can sell you a color 
chart composed of actual samples of anodized aluminum, or they can 
provide you with a simple printed color chart for free.

For those of you who are chemists and dye afficionados, one of their 
technical men told me that anodizing dyes are simply analine dyes of the 
anionic type. Having used analine dyes in the past for refinishing 
guitars, I called the company where I used to buy them; Mohawk Finishing 
Products in Amsterdam, NY, phone: (518) 843-1380. Mohawk sells them in 
all the popular colors used for wood finishing, PLUS black and several 
primary colors. One of their chemists told me that they ARE the anionic 
type, but that they are NOT lightfast and will fade if exposed to 
sunlight for any length of time. He said that among the primary colors, 
their red and orange are the most susceptible to fading, and that their 
black is the LEAST susceptible to fading.

That's the BAD news. The GOOD news is, that Mohawk will sell you an 8 oz. 
package of their #362-02244 black analine dye powder (ask for the 
water/alcohol soluble type) for just $21.95.

I've seen several postings on the ATM list this week recommending a 
company called East-West Dycom, so I called them, but their MAIN business 
is providing preanodized aluminum sheets, blocks, etc. to artists and 
industry, and they do the dyeing and the anodizing themselves. They WILL 
sell you the dyes, but in little 2 oz. packages for $25 each. Clariant 
and Mohawk clearly offer a better deal for your money.

Dave Sleeter 
-- 
Life is short and the path is often unclear.
It is a great sin to knowingly contribute to someone's confusion.