This type of container is highly resistant to penetration by water vapor and gives high protection to sutures moisture sensitive; therefore, synthetic absorbable sutures are well protected against degradation by atmospheric moisture diffused into the container through the heat seal during storage.
Synthetic absorbable sutures as homo-polymers and co-polymers of lactic and glycolic acids are known to be susceptible to degradation by hydrolysis, even by small amounts of water vapor. Care must be taken on using the container to substantially remove all suture moisture traces from inside the container to seal the suture in a substantially anhydrous environment.
Aluminum envelopes provide a perfect barrier against suture biological contamination and have adequate protection against water vapor entrance. When a conventional container is stored for long periods of time under conditions of temperature and humidity, a large amount of water vapor can penetrate into the container through the heat seal layer to attack and degrade the suture material.
Resistance to water vapor permeability of packaging sutures and sealed laminated heat is significantly better by providing an airtight container to the atmosphere, featured by an important lack of bubbles in the seal area.