Meaning of CEM-3 in English
CEM-3 is a laminate very similar to FR4. Instead of woven glass fabric a 'flies' type is used. CEM-3 has a milky white color and is very smooth. It is a complete replacement for FR4 and has a very large market share in Japan.
Electronics Terminology English vocabulary. Английский словарь терминологий электроники. 2012