Gore: Foam liners

The High Roll-Off Series of foam liners have full-surface construction to maximize airflow, offering a new level of safety when hazardous formulations are exposed to demanding conditions.

W. L. Gore & Associates (Gore) introduced two foam liners that set provides more standards for safety and versatility in packaging hazardous chemicals, agrochemicals, institutional cleaners, and household chemicals. As the latest additions to the GORE Packaging Vents portfolio, the new foam liners incorporate proprietary advances in venting technology.

Cap and container manufacturers will benefit, as these two versatile vents are drop-in replacements that satisfy a full range of packaging requirements. Chemical companies will enjoy more safety for their extremely hazardous chemicals – and anything less challenging, as well.

Gore Foam Liner High Roll-Off Series provides greater safety for the most aggressive chemicals

Gore’s newest membrane technology enables the High Roll-Off Series (3FL-363G) to set new standards in both airflow and liquid resistance. This offers a new level of safety when the most hazardous or challenging formulations are exposed to the most demanding conditions.

A new standard in airflow performance

The new High Roll-Off Series features Gore’s unique full-surface construction to maximize airflow: that is, the whole surface area of the liner is a breathable membrane with foam backer. This enables very high initial airflow, as measured through a dry membrane (typical airflow: 2.4 l/h at 12 mbar for a 28-mm. liner). Next, this vent has a “roll-off optimized” membrane that is proprietary to Gore. This enables the High Roll-Off Series to deliver residual airflow levels (measured after contact with fluids):

  • Residual Airflow: 95% measured with Gore Test Solution 1 (viscosity 3.2 mPas)
  • Residual Airflow: 90% measured with Gore Test Solution 2 (viscosity 9.6 mPas)

“Many vents have good initial (dry) airflow, but that airflow is obstructed after repeated contact with fluids,” says Ralf Knoellinger, Global Product Manager at Gore. “Our new High Roll-Off Series has very high initial airflow, combined with unprecedented roll-off properties that ensure fast airflow recovery. This means our new liner maintains exceptionally high residual airflow after repeated contact with the most challenging formulations. And that provides a whole new level of confidence in package integrity and packaging safety.”

A new achievement in liquid entry pressure (LEP) resistance

The new High Roll-Off Series provides extremely high WEP (Water Entry Pressure) resistance of 2.7 bar, and it also provides extremely high LEP (Liquid Entry Pressure) resistance. While both values indicate how “leak-resistant” a vent is, it is LEP resistance that matters in real-world conditions. For example, when a container falls over during transport, the liquid blocks the vent. As a result, over-pressure builds up inside the container, as the gas from decomposing chemicals cannot escape. As the surface tension of most formulations is lower than that of water (72 mN/m), these liquids may more easily penetrate the vent, even though water would not. Vents that test “water-tight” may in fact leak or spill aggressive chemicals under real-world conditions. The High Roll-Off Series has been extensively tested and proven effective at resisting leaks with the most aggressive chemicals, with viscous formulations and with low surface-tension liquids that defeat other vent materials. For example:

  • LEP Resistance: 1.7 bar with n-Butyl-Acetate (surface tension 31 mN/m)
  • LEP Resistance: 0.3 bar with acetic acid (surface tension 27 mN/m)

“Gore’s new High Roll-Off Series truly is one solution for the most aggressive chemicals, the most challenging applications, and all flat cap designs,” Knoellinger says. “We think of it as a worry-free venting solution that will give packaging manufacturers much greater peace of mind about safety, all along the supply chain.”

New Gore Foam Liner Standard Series

Gore also introduces its Standard Series (3FL-323G), for a versatile and economical solution to your everyday packaging applications that don’t demand a more sophisticated membrane solution.

Like the High Roll-Off Series, the Standard Series is a full-surface construction: it “breathes” across the whole surface of the liner, unlike single-point vents that have only a small breathing area. This gives the Standard Series a much higher initial airflow (typical airflow: 2.4 l/h at 12 mbar for a 28-mm. liner). Also, unlike single-point vents, this large breathable area is not easily blocked by drops of liquid.

In addition, Gore’s proprietary membrane technology was applied to deliver improved roll-off properties, for increased residual airflow. Using the same test fluids as before, the Standard Series delivers:

  • Residual Airflow: 40% measured with Gore Test Solution 1 (viscosity 3.2 mPas)
  • Residual Airflow: 10% measured with Gore Test Solution 2 (viscosity 9.6 mPas)

These levels make the Standard Series an ideal venting solution for multiple liquids. However, for liquids that are more viscous or highly aggressive, the High Roll-Off Series is preferred.

With WEP of 1.4 bar, the Standard Series is clearly competitive with other venting solutions available on the market. Regarding LEP, the Standard Series is effective with multiple formulations. For example:

  • LEP Resistance: 1.3 bar with n-Butyl-Acetate (surface tension 31 mN/m)
  • LEP Resistance: 1.4 bar with nitric acid (surface tension 41 mN/m)

But again, for highly aggressive or low surface-tension formulations, the High Roll-Off Series is the appropriate choice.

For cap and container manufacturers, these two new Gore foam liners can serve as drop-in replacements for single-point or other liners; both effectively vent “cap-thread” applications, making “hole-in-cap” venting unnecessary. Both work in multiple cap designs, so manufacturers can streamline their logistics and their inventory costs.

“Both new Foam Liners provide the proven Gore oleophobic protection that is trusted worldwide,” says David Zador, Global Product Manager for Gore Packaging Vents. “However, we used our membrane technology to create two distinct performance profiles: Our High Roll-Off Series is revolutionary, as it sets new industry standards for the most aggressive liquids and environments. Our Standard Series is a versatile solution for more typical or ‘everyday’ applications. For less challenging liquids, the Standard Series is more economical than the High Roll-Off Series—and it provides better performance than competitive offerings.”

Each of these new GORE® Foam Liners is available in various widths, as single- and multi-up roll goods, for a range of applications. Cut parts can also be provided.

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