The European Commission has focused their attention on two of the seven substances that are under consideration for EU RoHS restriction. The two substances being recommended for the RoHS Annex II list of restricted substances are: TBBPA and MCCPs (Table 1).
Table 1: Substances recommended for EU RoHS restrictions
| Substance(s) | Synonyms | CAS Number |
|---|---|---|
| Tetrabromobisphenol A (2,2',6,6'-tetrabromo-4,4'-isopropylidenediphenol) | TBBP-A | 79-94-7 |
| Medium- chained chlorinated paraffins –Alkanes, C14-17, chloro (chlorinated paraffins containing paraffins with a chain length of C14-17 – linear or branched) | MCCP | 85535-85-9 |
The consultants presented the results of their evaluation during a stakeholder webinar on April 27, 2020. A summary of some key information is provided below and links to presentation materials are provided at the end of this article.
Tetrabromobisphenol A (TBBP-A)
The consultants indicated that the primary uses for TBBP-A in EEE include:
- Precursor in the production of brominated epoxy resins that function as reactively flame-retarded substrate in printed wiring boards (PWB), ~90%
- additive flame retardant in thermoplastic EEE components, for example housings that consist of ABS plastic, ~ 10%
The general conclusion was that TBBP-A used as a resin in the production of printed circuit boards would be mostly consumed in the manufacturing process with residual TBBP-A remaining in the product generally below the 0.1% of homogeneous material threshold.
The focus of a restriction would be on TBBP-A as an additive flame retardant that remains in thermoplastic materials.
TBBP-A is also being assessed under the EU REACH regulation as a possible SVHC. The consultants are recommending that the results of the SVHC assessment be considered in any final RoHS restrictions
Medium-chain chlorinated parafins (MCCP)
The consultants presented the following MCCP uses and amounts:
- The main function of MCCPs is that of a secondary plasticiser (extender) in PVC -> it lowers the use of more expensive primary plasticisers.
- Moreover, MCCPs provide flame retardant properties and are added to PVC, rubber and other polymers.
- Noteworthy that MCCPs represent a substitute for short-chain chlorinated paraffins (SCCPs)
- The main EEE application area of MCCPs in the EU are PVC insulations and sheathing for electric cables and wires
- Typical concentration of MCCP in PVC insulation is 8-15 % of weigh. Total EU consumption for cable applications estimated in the range of 1,000 to 10,000 t per year
MCCP was also recently assessed under REACH and found to meet the criteria for consideration as an SVHC.
Further Information:
Links to the presentations from the stakeholder webinar are provided at the bottom of the webpage on interim results of substance review[1].
[1] Presentation from RoHS substance review, https://rohs.exemptions.oeko.info/index.php?id=341