Hello Werner,
The Isola site is also used to track order and ship status, invoicing, and
dock to stock in addition to technical details; so it would be entirely
appropriate that they do not just approve all comers but first understand
who is requesting access to what - so they are asking for 24 hours to
review the registration - if I were auditing them and they did not have
that control on those external accesses to those data files I would give
them a finding.
Many of the laminators use DSC; I agree with you that TMA is a more
appropriate and valid number; but I understand using DSC. I reserve my
pique for those that only list DMA results. Some do both or all three.
When I only see DSC, I subtract 10 degrees and call that value the
equivalent to the Tg by TMA - and move on. Since the IPC has test methods
for all three tests, they are all valid. Interestingly, IPC 4101 does not
require any Tg testing. For Tg it states that those are "optional tests as
agreed upon between user and supplier", and they reference both TMA and
DSC as "the tests" for Tg.
For IS410 and IS415 they show Z-TE as 50 to 260 (not 288) on the data
sheets I just reviewed on the web.
The form is not clear that Td is a 1% or 5% value, yes. I would write to
them and ask for clarification. If in doubt, I would use the worst case,
so unless told otherwise I would use 5%, especially as the spec calls for
5% as the threshold to take the reading. (There are other problems with
these tests and even if I knew it was supposedly 1% or 5%, I would still
only consider it a "reference" number.
x,y-TE is below Tg, so it is low. Almost all FR4s with woven glass are
somewhere between 10 and 14; and that number would also change in practice
when one moves from a raw laminate core to a cured multilayer board. So,
it is also a reference number. If I were to see something substantially
different, either high or low, then I would expect that laminate system to
perform differently from what we currently see. (for instance an Aramid,
or a StablCor...)
The page you reference is lagging behind the site's make over, since it
doesn't have any of Polyclad's laminates on it. Shame on them. But it
actually isn't that bad and it's better than nothing. I think it is an
attempt to simplify things for the not too materials' savvy user. It is
meant to be used, I believe, as a first pass screen to select candidate
materials. Then one would go get those specific datasheets to get "all the
info" on the specific materials of interest.
I think you are being too hard on them, and trust me, I do not give them a
"pass". But I do talk with them a lot, ask hard questions and expect
complete answers; offer suggestions for improvements and so forth. They do
respond. In general I would say that USA laminators didn't pick up on the
enormity of the research and development that it would take for RoHS
capable materials; ie: able to withstand lead-free process temperatures.
We're constantly engaged with the entire materials industry to get robust
materials to make our products on and we are in a race against time.
In any event, I myself would not single out Isola. They all have similar
short comings .... laminators: are you listening in??
Regards,
Valerie
Werner Engelmaier <[log in to unmask]>
Sent by: TechNet <[log in to unmask]>
05/19/2006 01:26 PM
Please respond to
TechNet E-Mail Forum <[log in to unmask]>; Please respond to
[log in to unmask]
To
[log in to unmask]
cc
Subject
Re: [TN] Rohs Weeeeeee board material
Hi Valerie,
Isola wants you to 'register'--a process that takea more than a day.
http://www.isola-group.com/en/products/name/detail.shtml?47??does not give
you Tg(TMA) [the most important, only Tg(DSC)] TE(50->288) instead of the
standard TE(50->260), and a Td for which it is not clear whether it refers
to 1% or
5% weight loss; if you try to get to ISxxx, e.g. IS410, you get Tg(DSC)],
TE(50->260) but CTE(x,y)=11-13 ppm/C?which cannot possible be correct, and
the
same Td uncertainty.
http://www.isola-group.com/en/products/CompatibleLaminate.pdf ??is totally
inadequate as far as properties is concerned.
Werner
---------------------------------------------------
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
-----------------------------------------------------
---------------------------------------------------
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
-----------------------------------------------------
|