| 摘要 |
1466641 Paper laminates COAL INDUSTRY (PATENTS) Ltd 19 Dec 1975 [15 Jan 1975] 1708/75 Heading B5N [Also in Division C3] Kraft paper laminates are prepared using as the laminating varnish a solution in methyl isobutyl ketone of a thermosetting resol resin that has been prepared by reacting a blend of a resinous reaction product, prepared by reacting an oxygen-containing naphthaleneformaldehyde resin with phenol, and a tar acid with formaldehyde in the presence of ammonia. The resintreated paper sheets are pre-cured by heating prior to lamination and are then compressed into laminates by heating under pressure. |
