Type of Bulletin: Technical Process BulletinProduct Title: Alodine T 5900 For Use as an Anodize SealProduct View:Description:Status: complete

Technical Process BulletinTechnical Process Bulletin No.

This Revision: 07/25/2006

Alodine T 5900 For Use as an Anodize Seal

1. Introduction:

Proper sealing is as important as proper anodizing. Sealing is a chemical or a physical process, which by absorption, chemical reaction, hydration, or other mechanisms increases the anodic coatings resistance to corrosion and staining.

Many common seals utilize hydrothermal conversion of the aluminum oxide produced in the anodizing step to form boehmite. Pure water, high temperatures, and long immersion times are needed to form boehmite. Mid-temperature seals work to produce a similar hydrothermal sealing effect but at a slower rate.

Alodine T 5900 is an effective low temperature seal (80 F to 110 F) for anodized coatings. The Alodine T 5900 sealing bath uses non-hexavalent chrome technology to uniquely seal the pores in anodic coatings. This chemical reaction sealing greatly extends the life of anodized coatings by increasing the overall corrosion resistance of the oxide film. This effectiveness is evident regardless of the acidic anodizing medium.

2. Operating Summary:

Chemical: Bath Preparation per 100 Gallons:

Alodine T 5900 2.5 3.0 gallons Alodine T 5900 Toner 0.5 0.6 gallons DI Water Remainder

Operation and Control:

Alodine T 5900 2.5 3.0% by volume Alodine T 5900 Toner 0.5 0.6% by volume Operating pH 3.8 4.0

Note: DI water, less than 5 microsiemens, must be used to charge the Alodine T 5900 tank.

For bath makeup, if the pH is less than 3.8, small additions of Alodine T 5900 Toner must be made with agitation or circulation

For bath makeup, if the pH is above 4.0, small additions of 5% by volume Sulfuric Acid must be made with agitation or circulation. Use Sulfuric acid only for this ph adjustment.

For working solutions, always make any needed additions of water, Alodine T 5900 to the bath and allow for complete mixing before measuring and adjusting the pH, as stated above.

Anodizing Type:

Sulfuric Acid

Seal Temperature 80 110 F (27 43 C) Seal Time 10 15 minutes Sulfuric Acid (Thin Film)

Seal Temperature 80 110 F Seal Time 10 15 minutes

Boric/Sulfuric Acid

Seal Temperature 80 110 F Seal Time 12 15 minutes

Phosphoric Acid

Seal Temperature 150 F (66 C) Seal Time 15 20 minutes

3. The Process:

1. Anodize using the required type.2. Water rinse (deionized water, RO water, or good quality tap water.3. Seal in Alodine T 5900 bath as directed above.

4. Water rinse (good quality tap water, must be clear and free of precipitates). This rinse can be used at room temperature or up to 140 F (60 C) to aid in drying.

Note: A contaminated rinse may produce powdery residues.

4. Equipment Recommendations:

PVC lined tanks are preferred for Alodine T 5900 seal solution and for the rinse tank following the seal. 316 stainless steel is also a satisfactory tank material. 316 stainless steel heating coils with a capacity to maintain the needed temperature are recommended.

Filtering of the seal tank is highly recommended for extending the sealing bath life. As with most seals, as the solution is utilized a fine precipitate will gradually appear in the solution. Once the precipitate reaches a certain level it may leave a slight powdery residue on the surface which usually is unacceptable. Filtering removes the precipitate and the powdering problem. Filtering alone will not ensure good results and long life. The quality of rinse water, rinsing practices and line conditions also affect bath life. Certain water soluble and non-filterable contaminants, such as phosphates, inhibit good sealing and require the bath to be dumped if they accumulate.

5. Testing and Control:

Never pipet by mouth, use a pipet filler bulb.

Concentration:Pipet a 10 mL sample of the Alodine T 5900 bath into a 100 mL volumetric flask and dilute to the mark with deionized water (dilution #1). Pipet 5 mL of the dilution #1 into a 500 mL volumetric flask and dilute to the mark with deionized water (dilution #2). Dilution #2 will be the testing solution (sample) for the following HACH Method 8024 needed to determine the chromium level.

HACH Method 8024, Alkaline Hypobromite Oxidation Method.

First fill the round Hach sample cell with 25 mL of the above sample (Dilution #2). Add the contents of one Chromium 1 Reagent Powder Pillow cap and mix well. Remove the cap and place in a boiling water bath for 5 minutes. Replace the cap and be sure to secure tightly. Cool the sample cell to 77 F (25 C) under running water. Remove the cap and add the contents of one Chromium 2 Reagent Power Pillow, cap and invert to mix. Remove cap and add one Acid Reagent Powder Pillow, cap and invert to mix. Remove cap and add one ChromaVer 3 Chromium Reagent Powder Pillow, cap and invert to mix. Allow a 5-minute reaction time.

Prepare a blank by filling another sample cell with 25 mL of the sample prepared in the 500 mL volumetric flask (dilution #2).

Zero the colorimeter with the blank and read the prepared sample.

To determine the bath concentration: Reading in mg/L of Prepared Sample X 11.79 = % of Alodine T 5900

To increase the value of Alodine T 5900 by 1 point (%):

Add 1 gallon of Alodine T 5900 to 100 gallons of the bath and follow with 0.2 gallons of Alodine T 5900 Toner.

6. Process Note:

1. When installing Alodine T 5900 sealing bath in a tank for the first time, make sure that the tank and heating coils are clean.

2. Make up the Alodine T 5900 solution using deionized water or approved tap water. Air or mechanically agitate when making any additions. Agitation is not recommended during sealing operations.

3. pH is extremely important in properly sealing anodized aluminum. A reliable pH meter is recommended for determining pH values. Sulfuric acid is used to lower the bath pH; Alodine T 5900 Toner is used to raise the pH.

4. Rinse thoroughly prior to sealing (two rinses preferred). Use a good overflowing tap water rinse or a slightly overflowing deionized rinse. Agitation is recommended in these rinses.

5. Maintain the concentration by making daily product additions. 6. Rinse thoroughly after sealing, using good quality water. It is important that this rinse be kept clear to avoid "powdering".

7. Precaution:

Consult the appropriate Material Safety Data Sheets for safety and handling guidelines for the products listed in this bulletin.

Testing Reagents and Apparatus(Order only those items which are not already on hand)

Code Quantity Item

xxxxxx ........... 2* ........... Volumetric Flask, 100-mL

xxxxxx ............2* ........... Volumetric Flask, 500-mL

592491 ........... 2* ........... Pipet, 5-mL Volumetric

592492 ........... 2* ........... Pipet, 10-ml Volumetric

592494 ........... 1 ............ Pipet Filler

Contact the Hach Company at (800) 227-4224 for the following reagents and apparatus.

24019-06 ......... 2 ............ HACH Sample Cells

22425-00 ......... 1 ............ Total chromium reagent set (100 tests)

* Includes one more than actually required, to allow for possible breakage.Beaker, 150-mL

Henkel Technologies32100 Stephenson HighwayMadison Heights, MI 48071Telephone: 248-583-9300Fax: 248-583-2976

"The information presented herein is our interpretation of certain test results and field experience to date. This information is not to be taken as warranty or representation for which we assume legal responsibility, nor as permission or recommendation to practice any patented invention without a license. It is offered solely for your consideration, investigation and verification." Henkel Corporation.

Henkel Technologies32100 Stephenson HighwayMadison Heights, MI 48071Telephone: 248-583-9300Fax: 248-583-2976

"The information presented herein is our interpretation of certain test results and field experience to date. This information is not to be taken as warranty or representation for which we assume legal responsibility, nor as permission or recommendation to practice any patented invention without a license. It is offered solely for your consideration, investigation and verification." Henkel Corporation.

Stand vom: gedruckt am: 09/18/2006-------------------------------------------------------------------------------------------------------------------------------------------------Verborgene Felder: 0Parker Amchem

Form Revised 04 June 2001