34 Discarding and recovering

Make portions of an object that have fulfilled their functions go away (discard by dissolving, evaporating, etc.) or modify these directly during operation.
  • Use a dissolving capsule for medicine.
  • Sprinkle water on cornstarch-based packaging and watch it reduce its volume by more than 1000X!
  • Ice structures: use water ice or carbon dioxide (dry ice) to make a template for a rammed earth structure, such as a temporary dam. Fill with earth, then, let the ice melt or sublime to leave the final structure.

Conversely, restore consumable parts of an object directly in operation.
  • Self-sharpening lawn mower blades
  • Automobile engines that give themselves a *tune up* while running (the ones that say *100,000 miles between tune ups*)
TRIZ principe 34


The colour indicates the ranking of the proposed principle to solve the contradiction: 1st, 2nd, 3rd, 4th.
This ranking reflects the frequency of occurrence of the principle in the analysed patents for this type of contradiction.
When a principle appears in first position, it means that it is statistically the most used in the patents studied for this type of problem.