| 507 / | HD | EARTH BORING, WELL TREATING, AND OIL FIELD CHEMISTRY |
|
| 200 | DF | WELL TREATING {4} |
| 203 | DF | .~ Contains organic component {17} |
| 209 | DF | .~.~ Organic component is carbohydrate or derivative thereof (e.g., sugar or gum, such as galactomannan, etc.) or carboxylic acid ester of an alcohol which has five or more hydroxy groups bonded directly to carbons {3} |
| 211 |  | .~.~.~ Carbohydrate is polysaccharide {4} |
| 212 | DF | .~.~.~.~> Polysaccharide is starch or derivative thereof |
| 213 | DF | .~.~.~.~> Polysaccharide is a xanthan (e.g., scleroglucans, etc.) |
| 214 | DF | .~.~.~.~> Polysaccharide is cellulose or derivative thereof {2} |
| 217 | DF | .~.~.~.~> Polysaccharide is hydroxyalkyl ether derivative (e.g., HPG, etc.) |