| 528 / | HD | SYNTHETIC RESINS OR NATURAL RUBBERS -- PART OF THE CLASS 520 SERIES |
| * | DD | SYNTHETIC RESINS (Class 520, Subclass 1) {23} |
| 271 | DF | .~ FROM CARBOXYLIC ACID OR DERIVATIVE THEREOF {10} |
| 310 | DF | .~.~ From imide- or lactam-containing compound, or from an amino-nitrogen containing carboxylic acid, or derivative of an amino-nitrogen-containing carboxylic acid {9} |
| 312 | DF | .~.~.~ Polymerizing in the presence of a specified material other than reactant {8} |
| 313 | | .~.~.~.~ Material contains a phosphorus or sulfur atom |