Patent ID: 8459099

Claim:
A method for producing closed, product-filled containers which are unleaky, and filled with a liquid, the method comprising: filling containers with a liquid; sealingly closing said containers; in-line leak testing one container after the other to establish whether said container is leaky or unleaky by: applying a pressure difference across at least a part of a wall of the container which part is to be tested by evacuating the surrounding of said container at least along said part of said wall to establish in said surrounding a pressure of at least vapor pressure value of at least one component of said liquid; monitoring the pressure course in said surrounding by means of a pressure sensor and evaluating the pressure course in said surrounding as monitored by said pressure sensor during the evacuating and from having reached said vapor pressure value to establish whether said container is leaky or unleaky, whereby a leak down to 0.02 μm is detectable for establishing leakiness, and wherein said in-line leak-testing to establish whether said container is leaky or unleaky occurs in a short test cycle time of a few seconds.