Clear coat anodize is a very common type of anodize that, as the name suggests, is typically clear. Clear coat anodize is most commonly used for cosmetic or architectural applications where corrosion resistance and “look” is of primary concern. Clear anodize has large pores which is why it typically appears to be transparent as you can essentially see through the anodize. Given its large pore structure, clear anodize is typically the best candidate to accept dye. Dyed clear coat will look much truer to the dye than hard coat anodize for that very reason.
One drawback of the large pore sizes, however, is the lack of hardness. As a result, clear coat is more susceptible to scratches and general wear and tear than hardcoat. One last consideration is the thickness. Clear coat anodize maximum thickness is around 1 mil. Making it about ⅓ of the maximum thickness achievable with hardcoat anodize. For many applications that doesn’t matter, but for some purposes thickness does come into play. It’s for those reason that we typically see clear anodize for cosmetic applications. That said, it still does possess remarkable corrosion resistance properties even at that thickness level.
Clear coat anodize will typically be used on indoor products for fingerprint resistance or for aesthetic value for products such as macbooks. Other applications include architectural beams where environmental exposure will be limited to corrosion to the air/rain, and dyed products such as paintball markers.
The most common specs using clear coat are architectural specs and Mil-A-8625-F Type 2 Class 1 or 2. The class 1 refers to applications with no dye. The class 2 refers to applications with dye. Beyond these common ones, customers often have specific OEM clear coat specs.
Many people ask if clear coat is cheaper than hardcoat. While the answer may vary from anodize shop to anodize shop, the answer is typically no, it is about the same. The reason is, despite lower thickness, the maximum voltage and ASF are capped resulting in about an equal amount of tank time.
For more information, feel free to contact us at Semano for a clear coat anodize (or hard coat) quote.