Request for Proposal
Status: RFP is Closed

Alternative Sealing Processes to Achieve Viral Barrier

Request Number
Due Date
Dec 5, 2019
Program Manager


Licensing, acquisition, supplier agreement, joint development, consulting


Phase 1 – Evaluation of proposed technologies and sample testing (3-6 months)
Phase 2 – Additional research & development + prototyping in a nonwoven fabric (Q4 2020)
Phase 3 – Implementation into a commercial product (Q4 2021)


To be negotiated

Please contact Tom Vranken,, if you are interested in submitting a proposal or if you need assistance with submitting your proposal

RFP was closed on
Dec 2019

RFP Title


Alternative Sealing Processes to Achieve Viral Barrier
RFP Description

NineSigma, representing a global manufacturer of disposable protective fabrics, invites proposals for sealing methods or technologies that can be used with disposable fabrics used in biological protective apparel. The technology should seal seams in laminated nonwoven garments in order to prevent pathogens, e.g. viruses or bacteria, from passing through protective apparel seams and infecting the wearer.


Our client is a major global manufacturer of disposable protective fabrics used in applications such as surgical gowns and biological protection coveralls. These fabrics are made of a nonwoven substrate consisting of polypropylene or bicomponent (PE & PET) spunmelt laminated to microporous, PE or co-polyester film. The laminated textile offers excellent protection against pathogens such as viruses and bacteria.

However, when garments are made from this laminated fabric today, the sealing techniques are not able to reliably seal complex seams sufficiently to pass the viral penetration resistance test (ASTM 1671 or ISO 16604) and, at the same time, to be economically feasible at an industrial scale. This can often lead to the seam being the weakest point of a garment design making the seam location the most likely pathway for harmful pathogens to pass through.

 A complex seam example would be the inseam or shoulder seam of various garment designs. It requires a non-linear sealing path that can create various seam geometries to satisfy all apparel construction processes. An example of a non-complex seam is a seam in a straight line to standard fixed length. 

Currently, four mainstream approaches are known in this industry. Unfortunately, these methods all have their drawbacks.

  • Glue Seam Seal (1-step process)
    • Slow manufacturing process
    • Glues may be expensive
    • Reliability issues in case the glue is not spread homogenously causing gaps in the barrier
  • Ultrasonic Heat Seam Seal (1-step process)
    • Reliability issues with viral barrier sealing of nonwovens (often caused by pinholes and gaps in the seam)
  • Bar Heat Seam Seal (1-step process)
    • Only seals in straight lines
    • Not suitable for complex seams
  • Sewn Seam with Tape Covering Seam (2-steps process)
    • Time consuming process to tape all seams with conventional tape
    • Often does not pass the ASTM 1671 viral penetration test.

The objective of this RFP is to find alternative approaches that seal complex seams of laminated nonwoven textiles while offering sufficient protection against pathogens. Our client is also open to the four, earlier mentioned technologies of which at least one of the drawbacks has been solved.
Eventually, the seal has to pass the ASTM 1671 tests (viral penetration resistance).

Key Success Criteria

The successful approach has to:

  • Seal complex seams of a laminated nonwoven fabric

The successful approach has the potential to:

  • be impervious to viral penetration (ASTM 1671 or ISO 16604) or resist fluid with a pressure of 2 PSI for 2 minutes
  • be applicable at an industrial scale
  • be applicable to create seams of fabrics with various designs and shapes (not only sealing straight seams)
Possible Approaches

Possible approaches might include, but are not limited to:

  • Improved Glue Seam Seal technologies
  • Improved Ultrasonic Heat Seam Seal technologies
  • Improved Bar Heat Seam Seal technologies
  • Improved Taped Sewn Seam technologies
  • Laser based sealing technologies
  • Any other approaches that sufficiently seal the seams
Items to be Submitted

We are looking for concise, non-confidential proposals. The proposal should contain:

  • Describe the approach/technology
  • How the technology is relevant to the current challenge?
  • Which key criteria can your solution meet now, on short term and longer term?
  • Level of maturity of the technology (development stage or just a proposal)
  • How adaptable is the technology, can it be optimized?
  • Is there a sample available or some evidence demonstrating it feasibility in your current application?
  • Description of your organization
  • Background information on the people involved in the proposal

To Respond, please use the Respond button located at the top or end of this page.

Preferred Collaboration Types
Area of Interest