There are many antonyms for the phrase "breaks the seal." Some of them include "secures the seal," "maintains the seal," "preserves the seal," "upholds the seal," and "protects the seal." These antonyms imply an action that ensures the seal is not broken or tampered with. "Secures the seal" suggests locking it in place, "maintains the seal" suggests keeping it in good condition, and "upholds the seal" suggests protecting it from outside harm. These antonyms are useful when discussing situations where maintaining the integrity of a seal is necessary, such as in shipping or storing goods that need to arrive in the same condition they left in.