The issue is revolving around the brominated flame retardant Tetrabromobisphenol A, which the
resin manufacturers have to add to epoxy resin to achieve V-0 flammabiliy rating.
Alternatives are based on phosphorous compounds.

Most polyimides do not contain bromine, but as you indicate, polyimides are several times as
expensive as FR4. For high-speed digital work you could use low cost PTFE/woven glass base
materials, like RF-35 from Taconic, which are in the BT-Epoxy price range. PTFE base
materials do not contain any flame retardant and are V-0 approved (due to the fluorine in the
molecular structure).

Manfred Huschka
Taconic

------------------------
  From: "Hollandsworth, Ron" <[log in to unmask]>
  Subject: [TN] FR4 Replacement
  Date: Thu, 8 Jul 1999 10:30:45 -0500
  To: [log in to unmask]


Hello TechNet

I have observed tons of conversation on Lead Free issues and speculation
which is great, however, I have a question concerning the replacement of
board material.  Specifically FR4.  I have heard that there is concern
surrounding the flame retardant used in FR4 and therefore FR4 may have to be
replaced by some other board material.  Polyimide may be an option, but what
will that do to cost.  Is polyimide more expensive?  Are there other
options?

Ron Hollandsworth
Ops Task Leader AME Group
ITT


---------------End of Original Message-----------------

--------------------------------------------------------
Manfred Huschka
Taconic Advanced Dielectric Division
Mullingar Business Park
Mullingar, Co. Westmeath
Republic of Ireland

NEW MOBILE PHONE NO.: +353/87/2858528

Office until July 31/1999: PF 1275, D-51676 Wipperfuerth, Germany
                           Tel.: +49 2267 888004
                           Fax:  +49 2267 888005

       after August 1/1999: Mullingar, Ireland
                            Tel. +353 44 34080 (direct)
                            Fax. +353 44 44369

E-mail: Manfred Huschka <[log in to unmask]>
Web: http://www.taconic-add.com
Date: 07/08/99
Time: 18:13:01

Taconic is exhibiting at European Microwave Week in Munich (Germany)
October 5 - 7, 1999. We look forward to meet you on our stand no. 16A.
http://www.eumw.com

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