Binder fibers are either fully meltable fibers of a low-melting polymer or bicomponent fibers whose sheath melts while the core survives. They are blended in at roughly 10 to 40 percent of a carded or airlaid web and activated in a through-air oven or a calender. Bicomponent binders are preferred where the web must keep its loft, because the fiber keeps its shape instead of collapsing into a blob.
Bump the binder fiber to 30 percent if the felt keeps delaminating after molding.
Also heard as
- binder
- bonding fiber
- melt fiber
Related terms
Bicomponent fiber
Fiber spun from two different polymers in one cross section, such as a low-melting sheath around a strong core.
Lo-melt
Shop name for low-melt polyester binder fiber, usually a copolyester sheath on a standard PET core.
Thermal bonding
Bonding a web by heating it so thermoplastic fibers or binder fibers soften and fuse at their crossing points.
Through-air bonding
Thermal bonding that pulls hot air through the web so binder fibers fuse without the web being crushed.