Foil and Tyvek-Lidded Trays and Blister Packs: Vacuum Decay CCI

Overview

Tyvek- and foil-lidded trays, along with related blister-pack formats, are a packaging class built around seal quality rather than a liquid fill. PTI's vacuum decay application here is specifically tuned to detect seal defects — incomplete seals, channel leaks, and foreign-material inclusions trapped in the seal line. For nonporous lidding it can also detect a pinhole or crack in the lid material itself.

For porous Tyvek lidded applications a custom test chamber masks the porous material while still allowing for leak detection of the seal area. Peel strength is an additional critical factor for most porous medical trays, and vacuum decay is sensitive to both over sealed and undersealed conditions making it ideal for both leak detection and drift in sealing condition.

Sample & Container Type

• Rigid or semi-rigid plastic trays sealed with a porous Tyvek lid or a foil lid
• Single- and multi-cavity tray designs (two, four, or more compartments)
• Paper/Tyvek blister packs

Product Class & Rheology

• Medical devices and device components packaged dry (unfilled with liquid)
• Products requiring ethylene-oxide or similar sterilization through a breathable Tyvek lid
• The seal itself, rather than a product fill, is the primary object of the test

General Test Method

For multi-cavity tray designs, a unified recipe is developed and validated across all cavities and tooling configurations used in production. Blind studies — in which the test operator does not know in advance which samples are defective — are a standard part of the validation approach, giving an unbiased measure of real-world classification accuracy.

Typical Findings & Sensitivity

Despite Tyvek's inherent porosity, tray programs consistently and successfully separate genuinely defective trays — whether from an incomplete heat seal, a wire or fiber inclusion caught in the seal line, or a physical pinhole or crack — from good trays within a short test cycle suitable for high-throughput, potentially inline inspection. Defect types spanning wire/fiber inclusions, incomplete seals, folded lidding material, and physical pinholes or cracks are all reliably and statistically separated from good trays, typically within a several-second test cycle.

Frequently Asked Questions

1. Does Tyvek's porosity prevent vacuum decay testing?

No. The baseline negative-control population already reflects the lid material's native porosity, and the reject threshold is set statistically relative to that baseline rather than assuming a hermetic seal.

2. What seal defects can vacuum decay detect on trays?

Incomplete seals, channel leaks, wire or fiber inclusions trapped in the seal line, folded lidding material, and physical pinholes or cracks in the tray or lid material.

3. Can multi-cavity trays share one test recipe?

Yes — a unified recipe is developed and validated across all cavities and tooling configurations (one-, two-, or four-cavity variants, for example) used in production.

4. Are blind studies part of tray validation?

The test method is 100% objective and deterministic. While blinding validation may seem necessary, the method is without bias.

5. What is a typical test cycle time for trays?

Tray testing is typically completed within a several-second test cycle, suitable for high-throughput or potentially inline inspection.

Why Clients Choose PTI for This Application

PTI develops the tray recipe around the specific porosity and tooling configuration of a client's actual design rather than a generic assumption about lid material, which is why seal-quality defects — not just gross material breaches — are reliably and statistically detected.