摘要 |
<p>1433092 Laminates CELOTEX CORP 25 Feb 1974 [26 April 1973] 8281/74 Heading B5N [Also in Division C3] A laminate comprises either (1) a paper facing sheet and a layer of a phenolic polymer cellular material, or (2) a layer of the said cellular material between 2 facing sheets of an asphalt impregnated felt. The cellular material is prepared from a phenolic composition comprising a phenolic polymer and free phenol prepared by (I) first reacting o-cresol and paraformaldehyde in the presence of NaOH and (II) then reacting the resulting intermediate with paraformaldehyde and phenol, and neutralizing the product.</p> |