CARDITE #1211
Additive For Aluminum Etching Solutions

Cardite #1211 increases the effectiveness and efficiency of any alkaline solution used for etching aluminum and its common commercial alloys; it is especially recommended for solutions of caustic soda. A unique blend of anionic/non-ionic surfactants and sequestrants:

...	it accelerates the alkali-aluminum reaction by reducing the liquid-metal interfacial tension.
...	it prolongs solution life with no scale formation by preventing the precipitation of hydrated alumina.
...	at common operating temperatures, even with air agitation, it presents no foam problem; at 100ºF and above it is virtually non-foaming.

Operating benefits are:

Quantity Required:

Cardite #1211 is used in proportion to the quantity of caustic soda in solution:

Recommended usage….......	1.0 gallon Cardite #1211 per 11 gallon 50% liquid caustic.
equivalent to………………	5.0 gallon Cardite #1211 per 55 gallon 50% liquid caustic.
equivalent to………………	11.7 ounces Cardite #1211 per 1 gallon 50% liquid caustic.
equivalent to………………	1.0 gallon Cardite #1211 per 70 pounds dry caustic.

Following are several common solutions of caustic soda and the quantity of Cardite #1211 required PER 100 GALLONS of solution:

Approximate Equivalent Solutions Of Caustic Soda				Use Cardite #1211
Caustic Soda	50% Liq Caustic per 100 Gallons	Dry Caustic per 100 Gallons	Dry Caustic per Gallon	Per 100 Gallons Caustic Solution
1.0%	1.3 gal	8 pounds	1.3 ounces	1.0 pint
2.0%	2.7 gal	17 pounds	2.7 ounces	1.0 quart
3.0%	4.1 gal	26 pounds	4.2 ounces	1.5 quart
4.0%	5.5 gal	35 pounds	5.6 ounces	2.0 quart
5.0%	6.9 gal	44 pounds	7.0 ounces	2.5 quart
6.0%	8.3 gal	53 pounds	8.5 ounces	3.0 quart
8.0%	11.0 gal	70 pounds	11.2 ounces	1.0 gallon
10.0%	14.6 gal	93 pounds	14.9 ounces	1.3 gallon
11.0%	15.7 gal	100 pounds	1.0 pound	1.4 gallon
50.0%	100.0 gal	638 pounds	6.4 pounds	9.1 gallon

Typical Application

Use tanks, hooks, chains, and racks which are not affected by caustic soda. Satisfactory materials are stainless steel, fiberglass and polyethylene. Tanks should have some device to provide agitation; compressed air injected at bottom is commonly used. Rinse tank should have continuous inflow and outflow of about one gallon per minute.

50% liquid caustic is recommended; it can be easily measured by volume, it dissolves instantly. Dry caustic will produce the same result but is harder to handle; see the follow table for equivalent solutions.

Recommendations based on using tanks with an operating capacity of 100 gallons:

Chemical Tank
Fill tank about ½ full with water…………………… 50 gallons approximately
Add 50% liquid caustic to make a 3% solution……. 4 gallons required
Add Cardite #1211 per the following table………… 1.5 quarts required
Fill to 100 gallons with water……………………… quantity required

Rinse Tank
Fill to 100 gallon overflow with water.

Procedure
Heat chemical tank to 160ºF
Start inflow water to rinse tank
Start agitation in both tanks
Immerse aluminum in chemical tank for 20 seconds
Remove aluminum; allow 1-second drip
Immerse in rinse tank for a least one minute.
Remove aluminum. It is ready for next operation or drying and storage

Additions To Chemical Tank & Variations

Note concentration range at which consistently good results are secured. As Cardite #1211 and caustic are depleted by use, add enough to restore to original concentration.

Find quantity of caustic needed by titration with phenolphthalein & hydrochloric acid. Add Cardite #1211 and 50% liquid caustic in ratio of 1:11 by volume. Normally, 10 to 20 additions can be made before sludge accumulation makes additions uneconomical. When additions fails to produce normal quality, discard the solution, rinse tank, and re-charge with a fresh solution.

Considerable variations can be made in caustic concentration, temperature, and immersion time. Cardite #1211 should always be used at fixed ratio of 1 gal Cardite #1211 per 11 gal 50% liquid caustic. Trial will indicate the most efficient usage levels & operating conditions for a specific alloy. Permissible variations are:

Caustic………...	1% to 6%. At low concentrations, more frequent additions are needed. At high concentrations, drag-out losses increase.
Temperature…...	160º recommended. 120º to 180ºF is normal operating range. Good work can be done at room temperature of 70ºF by increasing immersion time. But: at temperatures over 160º aluminum may dry to fast; if it dries before rinsing, spots or streaks may occur.
Time…………...	5 seconds to 10 minutes depending on caustic concentration, temperature, the specific allow being processed, results required.

Properties & Use Precautions

Cardite #1211 is a clear, amber liquid. Non-Flammable. Biodegradable. Odorless. Low viscosity; easy to pump or feed through metering devices. Neutral. Non-Hazardous. But: caustic soda is extremely hazardous; use appropriate safety measures.