ESL Diaphragm coating - Page 2 - diyAudio
Go Back   Home > Forums > Loudspeakers > Planars & Exotics

Planars & Exotics ESL's, planars, and alternative technologies

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th October 2007, 06:55 AM   #11
oshifis is offline oshifis  Hungary
diyAudio Member
 
Join Date: Mar 2004
Location: Budapest, Hungary
I have heard that vanadium oxyde (V2O5) is used on CRT TV-set screens to make it conductive against static charges, and it is soluble. Could it be perhaps used on diaphragms?
  Reply With Quote
Old 15th October 2007, 08:31 AM   #12
diyAudio Member
 
Join Date: Apr 2005
Location: Utrecht
All metaloxides I know of are not soluble unless cleaved into ions, I doubt this vanadiumoxid is.
__________________
drs M.J. Dijkstra
  Reply With Quote
Old 2nd November 2007, 02:09 PM   #13
diyAudio Member
 
Join Date: Jun 2006
Location: Austria
Has someone tried the Sony Patent US 5,590,212?

There, the PET-film is soaked for one or two hours in a water solvent solution containing a monomer (aniline, pyrrole or thiophene) and chemical oxidizer (for example ferric chloride) and a dopant. After washing the film with water you get a coating with a polymer layer as conductor. The patent claims that the coating is extremely thin (0,01-0,05 micron) and rarely affected by humidity.

Years ago I bought all the ingredients (pyrrole and ferric chloride) but never had the time for experimenting. So if someone needs some chemicals..but be prepared: not very healthy products!!

Nowadays I think we have very good ready made coatings and donīt have to waste our time with experimenting - so more time for finetuning our Eslīs! I have settled on the EC-coating from Martin-Jan now. Capacity is right: "Protect yourself from too many parameters not to be under control."

Harry
  Reply With Quote
Old 3rd November 2007, 08:18 AM   #14
Calvin is online now Calvin  Germany
diyAudio Member
 
Calvin's Avatar
 
Join Date: Nov 2004
Location: close to Basel
Hi,

havenīt tried that, because I asked a Dr. of Chemistry about the possibilities of fabricating and handling of this īsoupī.
While the components themselves should be not a big problem to obtain, the handling is said to be a bit critical and very bad smelling.
Meanwhile such conducting polymeres can be obtained ready to use. So thereīs no need to DIY it Yourself.
Besides the ready to use stuff has one great advantage: You can sectorize the diaphragm, while the soaking method coates the complete membrane.
A completely coated membrane can easily lead to flashovers at the outer rim of the panel as well as in close proximity to every spacer.
Therefore a coating that spares out the spacers and the outer rim is advantageous.

jauu
Calvin
  Reply With Quote
Old 3rd November 2007, 02:00 PM   #15
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Harry, polyaniline has been discussed before- you might want to search the forum for that discussion. It's not an optimal material for this application, especially if you live where the humidity varies.

The key point missed by 99% of amateur constructors and at least 75% of manufacturers is that the surface of the film is MUCH more important than the particular choice of coating. If the film is freshly corona or plasma treated and can achieve a surface energy of 45 dynes or higher, nearly any carbon-black loaded coating will stick heroically.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 3rd November 2007, 04:03 PM   #16
diyAudio Member
 
Join Date: Apr 2005
Location: Utrecht
corona treatment for using carbon-black...... I don't want carbon black!
__________________
drs M.J. Dijkstra
  Reply With Quote
Old 3rd November 2007, 04:12 PM   #17
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
A black with a high structure factor in a proper binder (choice is dependent on desired solvent and film type) will give a very uniform and high resistivity when thinned and sprayed or rolled on, assuming the film is surface treated properly (it almost never is). Graphite is a different animal and I don't think as well suited to low mass, high resistivity coatings.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 3rd November 2007, 06:40 PM   #18
diyAudio Member
 
Join Date: Apr 2005
Location: Utrecht
Hi

Do you know the average size of the carbon particles?
And what resistance?
If the pure compound has a very low resistance (for example graphite), it needs careful suspension to achieve high resistance, the higher the resistance, the more difficult this will be.
__________________
drs M.J. Dijkstra
  Reply With Quote
Old 3rd November 2007, 06:44 PM   #19
diyAudio Member
 
Join Date: Jun 2006
Location: Austria
Is the coating of the Esl-63 also carbon black?

I have attached two pictures. You see the coating of a nearly 20 year old Quad Esl-63 panel. These white points on the coating look like white ash. The foil is not damaged there. Before the rebuild you could hear sometimes a ticking sound. For sure a perfect leakage path at these points.

Harry
Attached Images
File Type: jpg esl-63_panel_1.jpg (46.9 KB, 1821 views)
  Reply With Quote
Old 3rd November 2007, 06:49 PM   #20
diyAudio Member
 
Join Date: Jun 2006
Location: Austria
and here is the second picture
Attached Images
File Type: jpg esl-63_panel_2.jpg (47.0 KB, 1767 views)
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
ESL Diaphragm Coating - HELP GlidingDutchman Planars & Exotics 12 11th October 2014 09:04 PM
PCB coating rs1026 Parts 10 3rd December 2011 12:08 AM
Help with diaphragm coating furly Planars & Exotics 6 17th January 2006 09:23 PM
Diaphragm coating Bazukaz Planars & Exotics 9 15th January 2006 08:27 PM
ESL diaphragm coating I_Forgot Planars & Exotics 58 4th April 2005 06:54 AM


New To Site? Need Help?

All times are GMT. The time now is 07:24 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Đ1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2