New product possibilities are on the horizon for manufacturers of wetlaid nonwovens and specialty papers with the addition of a flat PET fiber to the Cyphrex microfibers portfolio. This fiber, with its novel cross section, enables functional benefits such as uniformity, lightweight strength and improved processability compared with other synthetic microfibers. Flat PET Cyphrex fibers are less than 0.4 denier in size.

“In just over a year since launching, we have begun to build a complementary set of Cyphrex microfibers for wetlaid nonwovens manufacturers,” says Fred Dulin, director, microfibers platform, Eastman. “By offering round and flat fibers—in addition to the various sizes of Cyphrex—nonwovens producers can more precisely manufacture media to fit their customers’ needs, giving them an advantage in formulation capability.”

With its distinctive, consistent cross section, the flat PET Cyphrex microfiber improves nonwovens formation and sheet uniformity when compared with other synthetic fibers says Eastman. These characteristics provide functional benefits in the many applications for which dimensional consistency within and across the nonwoven is critical.

In addition, this flat PET fiber provides greater lightweight strength in nonwoven media. Compared with other synthetic fibers, Eastman Cyphrex flat PET fibers enable impressive tensile, tear and burst strength within a very lightweight nonwoven sheet, as well as outstanding green strength. In some applications, these fibers can improve strength-to-weight ratio and dimensional stability.


Because flat PET Cyphrex microfibers disperse easily in water, they are compatible with standard wetlaid and papermaking processes and equipment. These fibers do not require special shear or agitation. In addition, they allow for easy incorporation with a broader range of fibers than most other synthetic microfibers. And the consistent cross section of the fibers can give wetlaid nonwovens manufacturers confidence in fine-tuning media formulations for desired functionality.

“As with the larger, 4.5-micron fiber added to the Eastman Cyphrex microfibers portfolio earlier this year, the flat PET fiber is part of our ongoing effort to create and give our customers innovative microfibers that fit their specific needs,” Dulin says. “This is the latest example of how Cyphrex can keep creating new possibilities for wetlaid nonwovens manufacturers.”