TECHNET Archives

October 2004

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:
David Douthit <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, David Douthit <[log in to unmask]>
Date:
Thu, 28 Oct 2004 16:25:36 -0700
Content-Type:
text/plain
Parts/Attachments:
text/plain (148 lines)
Bogert,

You are quite correct. UR coatings are very difficult to remove once
they have reached a completely cured state.

HumiSeal created a 1 part UR that first "drys" as the solvents evporate
and then cures (cross-links the molecules) by reacting with Oxygen. It
is during the cross-linkage cure cycle that the 1A33 can be removed with
IPA. It simply gets more difficult to remove as the cure progresses
until the IPA won't work any longer (about 3 to 4 weeks at room
temperature).

David a. Douthit
Manager
LoCan LLC

- Bogert wrote:

> Type 1A33 coating is type UR.  No type UR is easy to remove.  Solvents
> used for removal can cause significant electrical problems if not
> completely removed by the subsequent cleaning process.
>
>     ----- Original Message -----
>     From: David Douthit <mailto:[log in to unmask]>
>     To: [log in to unmask] <mailto:[log in to unmask]>
>     Sent: Tuesday, October 26, 2004 7:02 PM
>     Subject: Re: [TN] conformal coating
>
>     James,
>
>     If I'm not mistaken 1A33 is a 1 part urethane coating that requires
>     extended curing times (>500 hrs) at room temperature. This coating
>     is a
>     two stage "cure". The stage is the evaporation of the solvents which
>     leaves a "touchable surface that feels dry. The second stage is the
>     "cross-linkage" that takes place when oxygen molecules permeate the
>     coating. Any attempts to "clean" surfaces coated with 1A33 before
>     this "cross-link" curing is complete will result in damage. The major
>     selling point for 1A33 is that it is easily removed and replaced for
>     repair work for two or three weeks after it is applied.
>
>     Because the "cross-link" portion of the cure requires oxygen, heat
>     does
>     not accelerate the curing process.
>
>     Just have them wait 30 days befor cleaning or use a 2 part urethane.
>
>     David A. Douthit
>     Manager
>     LoCan LLC
>
>     James TerVeen wrote:
>
>     >I am looking for a conformal coating that can withstand the use of a
>     >cleaner (Lixton TS-974)
>     >We have a customer who uses our parts that are coated with
>     Humiseal 1A33
>     >and is cleaning them in an ultrasonic cleaner that has Lixton
>     TS-974 in it.
>     >They are complaining that the coating is coming off.  With the
>     ingredients
>     >I see below there is no wonder.   So my first question was, is
>     there a
>     >conformal coating that will withstand this material or if not is
>     there a
>     >better cleaner I could recommend that will not remove the humiseal.
>     >Remember it has to go into an ultrasonic cleaner.
>     >
>     >Thank in advance.
>     >
>     >
>     >The ingredients are in this material are:
>     >LIXTON
>     >
>     >50 - 10%    4-Hydroxy-4-methyl-pentan-2-0n
>     >2.5 - 10%   N-methyl-2-pyrrolidome
>     >2.5%           Alkylaminethoxylat
>     >2.5%           modifiziertes Fettalkoholetethoxylat
>     >
>     >
>     >
>     >
>     >STATEMENT OF CONFIDENTIALITY:
>     >
>     >If you have received this e-mail in error, please immediately
>     notify the
>     >sender by e-mail at the address shown.  This e-mail and any
>     attachments may
>     >contain confidential information. This information is intended
>     only for the
>     >use of the individual(s) or entity to whom it is intended even if
>     addressed
>     >incorrectly.  Please delete it from your files if you are not the
>     intended
>     >recipient.  Thank you for your compliance.
>     >
>     >---------------------------------------------------
>     >Technet Mail List provided as a service by IPC using LISTSERV 1.8e
>     >To unsubscribe, send a message to [log in to unmask]
>     <mailto:[log in to unmask]> with following text in
>     >the BODY (NOT the subject field): SIGNOFF Technet
>     >To temporarily halt or (re-start) delivery of Technet send e-mail
>     to [log in to unmask] <mailto:[log in to unmask]>: SET Technet NOMAIL
>     or (MAIL)
>     >To receive ONE mailing per day of all the posts: send e-mail to
>     [log in to unmask] <mailto:[log in to unmask]>: SET Technet Digest
>     >Search the archives of previous posts at:
>     http://listserv.ipc.org/archives
>     >Please visit IPC web site
>     http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
>     information, or contact Keach Sasamori at [log in to unmask]
>     <mailto:[log in to unmask]> or 847-615-7100 ext.2815
>     >-----------------------------------------------------
>     >
>     >
>     >
>     >
>
>     ---------------------------------------------------
>     Technet Mail List provided as a service by IPC using LISTSERV 1.8e
>     To unsubscribe, send a message to [log in to unmask]
>     <mailto:[log in to unmask]> with following text in
>     the BODY (NOT the subject field): SIGNOFF Technet
>     To temporarily halt or (re-start) delivery of Technet send e-mail
>     to [log in to unmask] <mailto:[log in to unmask]>: SET Technet NOMAIL
>     or (MAIL)
>     To receive ONE mailing per day of all the posts: send e-mail to
>     [log in to unmask] <mailto:[log in to unmask]>: SET Technet Digest
>     Search the archives of previous posts at:
>     http://listserv.ipc.org/archives
>     Please visit IPC web site
>     http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
>     information, or contact Keach Sasamori at [log in to unmask]
>     <mailto:[log in to unmask]> or 847-615-7100 ext.2815
>     -----------------------------------------------------
>


---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

ATOM RSS1 RSS2