Boric acid in PCBs: compliance with EU REACH regulations
Source abstract
Abstract
Purpose Boric acid has been used for many years as a catalyst inhibitor and crosslinking agent to increase the glass transition temperature of epoxy resins for printed circuit boards (PCB), as well as in the glass fibre reinforcement. Recent regulation related to boric acid and its salts by the ECHA, a regulatory agency in the EU, may limit the use of these materials. The purpose of this paper is to describe the implications of this new regulation and to propose an analytical procedure that is relevant to PCB's. Design/methodology/approach Potential analytical procedures, including dissolution in acid and aqueous extraction followed by boric acid titration, are discussed and evaluated. Findings The use of acid for the digestion of prepreg, laminates and PCBs has the potential to greatly overstate the concentration of boric acid in PCBs. Originality/value An aqueous extraction method (German DIN 38414-4) gives results that represent a worst-case leaching process. It is proposed that it becomes the official analytical method for printed circuit boards in order to comply with the ECHA regulation.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Recycling and Waste Management Techniques
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Dow Chemical Company, Freeport, Texas, USA
Isola Group, Chandler, Arizona, USA
References (7)
Show source-provided references
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