| 528 / | HD | SYNTHETIC RESINS OR NATURAL RUBBERS -- PART OF THE CLASS 520 SERIES | 
| * | DD | SYNTHETIC RESINS (Class 520, Subclass 1) {23} | 
| 230 | DF | .~ FROM ALDEHYDE OR DERIVATIVE THEREOF AS REACTANT {12} | 
| 232 | DF | .~.~ Polymerizing in the presence of a specified material other than a reactant {4} | 
| 240 | DF | .~.~.~ Material contains a boron atom {1} | 
| 241 |  | .~.~.~.~ Boron trihalide or organic complex thereof |