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Mr. Laminate Tells All: Where in the Holy Halogens did 900, 900, 1500 Come From?

I took the requirements from IEC-61249-2-21 and imported them into the IPC standards development process, creating document IPC-4101/92. The test method for the determination of halogen content in base materials, IEC 61189-2C12, was imported into the IPC manual simply by rewriting it in IPC format. IPC-TM-650 Method 2.4.41 was the test method number used by the IPC to determine the halogen content of FR-4 CCL. Underwriters’ Laboratories (UL) uses this test today to define which products are ANSI grade FR-4.0 and which are ANSI grade FR-4.1.

From that time, other IEC and IPC documents have been developed for epoxy, polyimide and cyanate ester halogen-free CCL grades and prepregs. The requirement has also always remained as 900, 900, and 1500, as previously discussed. Only one test method has been referenced.

Neither TC91/WG4 nor IPC planned to use this requirement for any other products other than CCL in the electronics supply chain. The specification was developed for and was only applicable to FR-4 CCL and prepreg. However, some years later, several OEM computer manufacturers and others decided that the 900, 900, 1500 requirements could be applied to everything else in the electronics supply chain, including soldermask, legend ink, adhesives, cases and power cords. PVC, used in many electronics applications, was now also to be eliminated as it contained chlorine.

This expansion to other materials was supposed to be documented in a new standard, IPC/JEDEC Joint Standard 709, but there was controversy as to why a CCL specification had relevance to soldermask or adhesive or anything else for that matter. There was also a belief that chlorine and bromine should only be reported if it came from organic chlorine and bromine found in flame retardants. Additionally, there was also discontent as to why fluorine was not considered a halogen for definition purposes. I still wonder that, too. However, after several years of meetings, comments and balloting, this document was never published by IPC, but JEDEC did decide to publish by itself and under their own logo.

I have seen many announcements in trade journals indicating that some new material in the electronics supply chain has been developed and is halogen-free based on the 900, 900, 1500 requirements. Of course these requirements are not related to any historical testing on the materials referenced. The requirements are not being pulled from thin air but more like rarified air.

I apologize on behalf of myself and Dr. Shibata for creating this requirement that has been exported into so many areas unrelated to CCL.

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