Technical Absorbents Limited (TAL) has
developed a new grade of superabsorbent fibre (SAF) specifically for use within
a new range of SAF nonwoven fabrics that are more resistant to shrinkage.
The new SAF was developed in response to
the demand from the medical industry for a superabsorbent fabric suitable for
use in advanced wound pad dressings. The fibre had to be capable of
withstanding the moisture used in the EtO sterilization process that is
frequently employed in the production of the pads, in order to ensure product
safety and compliance.
EtO sterilization is a low-temperature
process (typically between 37 and 63°C) that uses ethylene oxide gas to reduce
the level of infectious agents. While generally applied in gas form, however,
the EtO is usually mixed with other substances – and often steam.
“Superabsorbents and moisture generally
aren’t a good combination at this stage in processing and can cause problems,”
said TAL Product Development Director Dr Mark Paterson. “Other methods can be
used, but when silicone materials are included, EtO is the preferred treatment
method. Regular SAF grades tend to shrink a little and can become hard, which
is often not desirable. This innovative SAF grade significantly reduces such
potential problems.”
The amount of shrinkage caused by EtO
sterilization depends very much on the product design and construction, he
added, but in general, the new SAF has been tested and proven to reduce fabric
shrinkage by around 70%. It is suitable for use in all SAF nonwoven formats,
whether needlepunched, thermally bonded or airlaid.
While the proprietary process developed at
TAL for the production of this new fibre and resulting fabrics was prompted by
the specific requirements of wound pad dressings, TAL sees opportunities for
its application in other areas as well.
“It’s
a flexible fibre that can be easily switched with existing SAF grades when
manufacturing fabrics and we have a number of current projects in which we’re
exploring other end-uses,” Mark concluded.