The Blackening Process
and Chemistry

1. Insta-Blak Turnkey Blackening Equipment Looking to upgrade, expand or add a metal blackening line? EPI provides turnkey blackening setups to make your installation a quick, easy, and inexpensive process. Get more information on Insta-Blak Turnkey Blackening Equipment

   Cleaning: Soils such as cutting oils, coolants, lubricants and rust inhibitors must be removed.
   
   E-Kleen 148E, a low caustic liquid concentrate used at 10% in tap water with immersion of the parts for two to five minutes at 120° to 150° F, or:
   
   E-Kleen 102-E, a high caustic alkaline liquid concentrate used at 10% in tap water at 120-160° F for the heavy-duty cleaning of heavily soiled parts.
   
2. Rinse in cold, overflowing tap water. It is necessary to rinse the parts to remove residual cleaning solution. Parts carrying over an unrinsed clinging film of alkaline cleaning solution would quickly contaminate a subsequent step of activation or blackening resulting in a spotty or non-adherent black finish. Immerse for 30 to 60 seconds.
    
3. Blackening: Insta-Blak 333, a single component, liquid concentrate which is used at 10% by volume in tap water to blacken carbon steels, alloy steels, tool steels, as well as castings, forged steels and powdered metal. It will not blacken stainless steel. Parts are immersed at room temperature for 2-5 minutes. For high volume lines or custom formulation a two component system, Insta-Blak 333 M/E is utilized.
    
4. Rinse in cold, overflowing tap water for 30 to 60 seconds to remove residual blackening solution.
    
5. Seal the finish by immersing the parts for one minute in a compatible E-Tec water displacing rust preventive solution.
   
   The E-Tec corrosion inhibitors are formulated to rapidly displace the residual acidic solution from the preceding rinse. The Insta-Blak finish will absorb the E-Tec solution, producing long term corrosion protection. As the E-Tec is absorbed, it enhances the depth of blackness which may take several hours.
   
   E-Tec formulations are available for oily finishes, dry-to-the-touch soft finishes and dry, clear hard finishes.
   
   E-Tec 501 is formulated to give a very rapid water displacement and to leave a thin, transparent, corrosion-resistant film. It will not gum-up under high humidity and high temperature conditions. It leaves a slightly oily film with maximum corrosion protection.
   
   E-Tec 503 — same as E-Tec 501 but leaves a very light oil film.
   
   E-Tec 504 — similar to E-Tec 503 but leaves a dry-to-the-touch film.
   
   E-Tec 505+ — same as E-Tec 504 but leaves a much thicker, dry, soft film with maximum corrosion resistance.
   
   All of the above solvent-based E-Tec water displacing formulations are available as E-Tec NVOC formulations which eliminate the release of VOC's to the atmosphere.
   
   E-Tec 520 — a gloss clear acrylic lacquer.
   
   E-Tec 521 — a gloss clear, water-based wax.
   
   E-Tec 521-B — a black glossy, water-based wax.
   
   E-Tec 522 — a satin clear, water-based wax.
   
   Activation: In most applications an alkaline cleaning in E-Kleen 148E is sufficient prior to blackening. However, some difficult-to-blacken steel alloys will require an activation in an E-Prep solution to make the steel surface receptive to the blackening reaction. This step is inserted after step 2 above, followed by an additional rinse.
   
   E-Prep 258 — a general purpose surface conditioner/activator used on cast iron, steel, leaded steel alloys and other difficult-to-blacken steel alloys. Liquid concentrate is used at 20% by volume in tap water at 65-75° F (room temperature).
   
   E-Prep 255 — a surface conditioner/activator used on very hard polished tool steel surfaces. It eliminates iridescent blue finishes and produces a deep black color when used prior to Insta-Blak. It is also used as a combination light duty cleaner and activator to eliminate the alkali

   Ion Exchange for Insta-Blak

   Ne cleaner for steel surfaces which have been sand or glass bead blasted or processed in a vibratory unit. Liquid concentrate used at 10% by volume in tap water at 75 to 120° F.
   
   Click here for more information on metal blackening.

Environmentally Friendly -- Zero Discharge

In those rare instances where the concentration of metallic ions exceeds local regulations, an ion exchange unit can be installed on tank 4 to remove them.

EPI can customize a process for your particular application, and design and supply you with the necessary equipment.