PaintSquare.com


The First Word in Protective & Marine Coatings

A Product of Technology Publishing / PaintSquare
JPCL | PaintSquare News | Durability + Design | Paint BidTracker

Free Download of

Problem Solving Forum

| More

December 17 - December 23, 2012

What causes bubbling or cratering of epoxy intermediate coat when applied over epoxy zinc-rich primer?



More items for Coating Materials


Selected Answers

From sasha bacic of none on December 18, 2012:
    The zinc-rich primer is a porous coat in which the air is entrapped. To avoid bubbling, there are two solutions: overcoating with a specifically formulated, so-called "sealing" coat before application of the subsequent coat; and using the so-called technique, "full-over-the-mist," which consists of diluting the coating up to 60% or more, then applying it in the form of a mist onto the zinc primer. The highly diluted paint will penetrate into the porosities of the primer and seal them. The next step is to apply the non-diluted paint immediately after the mist coat to ensure perfect adhesion. Of these two methods, the applicator may select the one with which he is more comfortable (depends of the experience of the applicator) and which is acceptable to the client. Comparative testing is recommended to assert which method to select. Contractor and client shall sit down and agree on testing parameters and evaluation criteria. It is far better to discuss before than after.

From Jorge Lizarraga of International Paint on December 17, 2012:
     Bubbling is caused by the air trapped among the zinc particles. To avoid this effect, it is necessary to apply a very diluted first coat in order to displace the air. Then, coat it as normally.

From Kiran Pawar of Berger Paint Bahrain on December 17, 2012:
Porosity present in the zinc-rich primers is responsible for the generation of bubbling or blistering when topcoated with thick coatings. In order to avoid this situation, apply a thin coat as a mist coat before going for thick coat.

Please sign in to submit your answer this question    

Tagged categories: Epoxy


Current PSF Question | Submit a PSF Question | Full PSF Archive

Polyval Coatings
Polyflex® Polyurea Linings

exhibit outstanding versatility in use; providing abrasion resistance, superior seamless waterproofing and high-chem corrosion protection. www.polyflexlinings.com


Wasser High-Tech Coatings Inc.
Wasser Coatings Protect

some of the most important bridges in the country; learn about our NEPCOAT-approved system and our entire range of MCU & Polyurea coatings. 1-800-627-2968 www.wassercoatings.com


Sherwin-Williams

Sherwin-Williams
Our 3,500 locations give you a level of service that is simply unmatched.


Mitsubishi Gas Chemical America
Performance Amine 1,3-BAC

A highly reactive cycloaliphatic diamine offering superior performance. Reasonable cost and curing efficacy makes it suitable for all types of epoxy resin applications.


BASF
New resins from BASF will have metals loving water:

Excellent corrosion resistance, low VOC, high gloss, thin films basf.us/industrialcoatings
polyorders@basf.com
800-231-7868


U.S. Zinc

The proven corrosion protection properties of our zinc dust prolong the life of marine coatings. U.S. Zinc – Helping the world work™


KTA-Tator, Inc. - Corporate Office
KTA-Tator EH&S Services

• Ambient & Worker Exposure Air Monitoring
• Safety & Health Program Development
• Lead Paint Assessments
& Specifications
• Health Hazard & Jobsite Safety Assessments
Call 1-800-245-6379

 
 
 
Technology Publishing

The Technology Publishing Network

The Journal of Protective Coatings & Linings (JPCL) PaintSquare
Durability + Design Paint BidTracker JPCL Europe

 
EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
MORE:      About PaintSquare.com   |   Privacy policy   |   Terms & conditions   |   Site Map   |   Search   |   Contact Us
 

© Copyright 2000-2014, Technology Publishing / PaintSquare, All rights reserved
2100 Wharton Street, Suite 310, Pittsburgh PA 15203-1951; Tel 1-412-431-8300; Fax 1-412-431-5428; E-mail webmaster@paintsquare.com