Innovative Panel Plating for Heterogeneous Integration
A Method to Investigate PCB Supplier Rework Processes and Best Practices
The Effects of PCB Fabrication on High-Frequency Electrical Performance
Aerosol Jet Printing of Conductive Epoxy for 3D
EOS Exposure of Components in the Soldering Process
High Thermo-Mechanical Fatigue and Drop Shock Resistant Alloys
Filling of Microvias and Through Holes by Electrolytic Copper Plating
NASA DOD Phase 2: Copper Dissolution Testing
Latest Industry News
How Telecom is Rolling Out 5G During a Pandemic
Can Software Performance Engineering Save Us From the End of Moore's Law?
Tech stocks have been a winning bet, but investors worry it will fade
All This Chaos Might Be Giving You 'Crisis Fatigue'
Notebook PCB makers to see tight capacity through 3Q20
How Effective Is Nano Coating On Stencils?
U.S. Critical Infrastructure Full of Security Holes
Auto Interior Is the New Exterior

The Disappearing Ink

The Disappearing Ink
UV lamps were bleaching out the blue color so that a new ink looked like a clear coating. Why didn't this happen in the lab?
Mysteries of Science


The 3M Company was developing a new ink hardening system. Normally, inks dry by solvent evaporation or they are hardened with heat.

The new approach would use ultraviolet radiation. A small batch of blue ink was made up and run through the small UV processor in the lab. The resulting ink came out hard and had good adhesion to the aluminum test panels.

Other tests confirmed that the ink properties were satisfactory. The batch was scaled up in a production run when they realized the UV was bleaching out the blue color so that the ink looked like a clear coating. 

But why didn't this happen in the lab? 

Here's the rest of the story.

It seems that the extra lamps and the additional ozone was enough to chemically modify the blue dye molecule to one that had no light absorption. Take note, scale-up can have surprises.


No comments have been submitted to date.

Submit A Comment

Comments are reviewed prior to posting. You must include your full name to have your comments posted. We will not post your email address.

Your Name

Your Company
Your E-mail

Your Country
Your Comments

Board Talk
How Effective Is Nano Coating On Stencils?
What Causes Board Delamination?
01005 Component Challenges and Bugs
Sticky Residue Under Low Clearance Parts
Soldering Relays Intrusively in Lead Free Process
Printing vs. Dispensing
Maximum Board Temperature During Tin-Lead
Is There a Spacing Spec for SMD Components?
Ask the Experts
Recommended Fiducial Shape
HASL vs. Immersion Gold
Very Low Temp PCBs
Looking for Long-term Component Storage Options
Baking After Cleaning Hand Placed Parts
Conformal Coating Recommendation
Burned Chip Repair
BGA Component Grounding Problem