TECHNET Archives

May 2018

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Yuan-chia Joyce Koo <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Yuan-chia Joyce Koo <[log in to unmask]>
Date:
Wed, 2 May 2018 18:23:38 -0400
Content-Type:
text/plain
Parts/Attachments:
text/plain (35 lines)
not necessary.  365 selected because the lamp got strong wavelength -  
it depend what FL dye you use, 400 nm might not excited as much (on  
the tail end).  you need to consult with your vendor chemist and let  
them know you intend to use 400 nm LED,  they might change  the  
formulation to shift the absorption wavelength... (I used to work  
with UV curable with vendor, need to spice formulation in order to  
utilize LED... of course, you can always get Purple LED that operate  
close to 365nm... 360-370 nm if I recall correctly... many moons  
ago... not many on market years ago).
IMHO.
jk
On May 2, 2018, at 4:12 PM, Douglas Pauls wrote:

> OK, I have a conformal coating question being debated internally  
> related to
> the wavelength of light used for black light inspection of conformal
> coating.  Fluorescent lights tend to emit more around 365 nm, which is
> where you get the most fluorescence from the dye.  I would like to  
> use some
> of the new LED black lights, lower power, longer life, much  
> brighter, but
> they emit in the 395-410 nm wavelength.  Seems to illumine the  
> coating just
> as well, but am getting pushback from some areas of the company.   
> So, here
> is my question:
>
> Are there coating features or defects which you can see at 365 nm,  
> which
> you cannot see at 395-410 nm?
>
> Doug Pauls
> Principal Materials and Process Engineer
> Rockwell Collins

ATOM RSS1 RSS2