MICRALOX – Differences

MICRALOX is a patent-pending partially micro-crystalline aluminum oxide coating that outperforms conventional anodic coating processes for aluminum. Opposed to conventional anodized aluminum oxide coatings (in an amorphous form, where molecules are in a random arrangement), micro-crystalline aluminum oxide molecules are packed in a regularly ordered, repeating pattern, resulting in a thermodynamically stable, lower soluble form.

Sister Chemistries

Since the inception of the original MICRALOX, Precision Coating has introduced two sister chemistries to the MICRALOX family: MICRALOX® Ultra and MICRALOX® Lumina.

MICRALOX® Ultra

When maximum performance for strong alkaline cleaning is critical to quality, MICRALOX® Ultra provides 50X the chemical resistance compared to decorative Type II anodizing. Aluminum parts coated with MICRALOX Ultra can withstand high-pH cleaning and sterilization protocols commonly used in European markets. MICRALOX Ultra coated parts can also withstand many other aggressive environments that would otherwise strip conventional anodic coatings and subject the parts to extensive corrosion.

As with all MICRALOX coatings, MICRALOX Ultra can receive embedded Sanford Print for crisp, permanent markings that do not delaminate, fade, or chip. This combination of best-in-class chemical- and corrosion-resistant coating and non-destructive markings provides the maximum protection for medical instruments for superior in-field performance.

For more information on MICRALOX Ultra performance, download this coating datasheet.

MICRALOX® Lumina

The clear, translucent oxide of MICRALOX® Lumina provides a perfect balance of breakthrough chemical resistance and design flexibility for medical device applications. Whether left natural, or dyed one of nine vivid colors, MICRALOX Lumina coatings achieves 16X the resistance in a hot alkaline strip test compared to Type II decorative anodizing. Unlike conventional anodizing and hard coat, the partially crystalline anodic coatings of MICRALOX Lumina hold up over a life-time of regular cleaning and sterilization without fading, chalking, or corroding.

As with all MICRALOX coatings, MICRALOX Lumina can receive embedded Sanford Print for crisp, permanent markings that do not delaminate, fade, or chip. This combination of superior chemical- and corrosion-resistant coating and non-destructive markings provides assurance for a full life-time of stringent cleaning and sterilization, as required of all medical devices.

For more information on MICRALOX Lumina performance, download this coating datasheet.

On the left, a sample of aluminum coated with MICRALOX that has been through a 12.5 pH cleaning and sterilization process 10 times. On the right, a sample of anodized aluminum that has been through a 12.5 pH cleaning and sterilization process 10 times.

The table below compares the various characteristics of conventional anodic coating and MICRALOX micro-crystalline aluminum oxide coating.

Characteristic Conventional Aluminum Anodic Coating MICRALOX®
Corrosion Resistance Fair Very Good; Enhances Corrosion Resistance by a factor of 10; unsurpassed corrosion resistance
Chemical Stability Fair Very Good; Micro-crystalline forms an effective barrier layer enhancing chemical stability. Crystalline structures exhibit a dramatically enhanced chemical stability due to outstanding bond strength
Cost Excellent Excellent
Thermal Conductivity Very Good Very Good
Environmental Impact Very Good Very Good (Fully RoHS Compliant)
Decorative (Color Anodizing) Poor to good, depending on type of conventional anodic coating Excellent; No color fading; can be dyed to a broad spectrum of colors, along with material finishes, from matt to high gloss
Durability Excellent Excellent

Other benefits of MICRALOX® include excellent steam resistance, outstanding dielectric properties, strict and consistent adherence to tight tolerances, and full RoHS compliance.  Unlike conventionally dyed aluminum parts and forms, where the dye is susceptible to leaching following the auto-clave sterilization process, the pores in MICRALOX® micro-crystalline aluminum oxide coating are completely stable, resulting in no contamination and color fading.  In addition, MICRALOX® aluminum anodic coating has increased dielectric characteristics when compared to a hard coat anodizing of similar coating thickness – this results in the aluminum remaining further insulated from carrying an electrical current or charge – an important safety attribute for many electrical insulation applications.  Also, as opposed to plastic and nylon coatings, MICRALOX® micro-crystalline aluminum oxide coating is formed to deliver consistent, uniform coating thickness tolerances across all dimensions of the aluminum part, thereby resulting in a highly engineered fit between components.  Finally, MICRALOX® micro-crystalline aluminum anodic coating is fully RoHS compliant (unlike other corrosion inhibiting technologies based on heavy metals).