Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Phoshate in paint ??

Phoshate in paint ??

Phoshate in paint ??

I am not an expert on paint :(
can anyone let me know:
2) what does phosphate do to paint

the paint that I use is for outdoor metallic components

thanks Dave

RE: Phoshate in paint ??

Ecoat is an abbreviation for electrocoat.  This type of coating (often epoxy based) is applied in an electrically charged bath that promotes even coverage.

Phosphate refers to a primer layer applied before paint that promotes adhesion of the paint.  The actual composition of this layer is a metallic phosphate: usually zinc phosphate, but could be iron phosphate or even manganese phosphate.

If your application is outdoors, beware that epoxy-based ecoat is susceptible to damage from ultraviolet radiation.  It would be best to use a UV-resistant topcoat like urethane or acrylic.



Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

RE: Phoshate in paint ??

CoryPad covered it pretty well, but I just want to mention that there are certain "reactive" primers (wash primers) that contain phosphoric acid. The acid package is mixed with the primer base and after a short dwell time the resultant primer is applied to the substrate. The phosphoric acid acts to facilitate the bond of the primer to the base metal. The use of these types of primers eliminates the need for a separate phosphate pre-treatment.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close