| 528 / | HD | SYNTHETIC RESINS OR NATURAL RUBBERS -- PART OF THE CLASS 520 SERIES |
| * | DD | SYNTHETIC RESINS (Class 520, Subclass 1) {23} |
| 10 | DF | .~ FROM SILICON REACTANT HAVING AT LEAST ONE SILICON-TO-HYDROGEN OR -CARBON BOND {12} |
| 12 | DF | .~.~ Polymerizing in the pressence of a specified material other than a reactant {6} |
| 21 | | .~.~.~ Material is a nitrogen-containing compound {1} |
| 22 | DF | .~.~.~.~> Nitrogen-containign silicon compound |