Nonwovens Vs. Woven Sponge (Gauze) Fabrics
The world of fabrics can be overwhelming, especially when you start to dig into the details. There are a variety of questions: How are fabrics made? How does production affect their capabilities? Which fabric works best for a specific application? Today we’ll answer some of these questions, breaking down the differences between nonwoven and woven fabrics, and how that applies to Richmond Dental and Medical’s sponge products.
Just by the word “nonwoven,” you know a nonwoven fabric is not a woven fabric. Production of nonwoven fabrics only requires a few steps. It’s important to note that production of woven gauze fabrics requires that the fibers be made into yarn first; then those yarns can be woven into fabrics. All conventional gauze is made from woven fabrics, while all nonwoven sponges are made from hydroentangled fabrics.
Production of Nonwovens from Staple Fibers:
Production of Woven Fabrics from Staple Fibers:
As you can see from the diagrams above, producing nonwoven fabrics has fewer steps than woven or knit fabrics. Also, the production speed for making staple fiber nonwoven fabrics is much faster (100 -400 yards per minute) than woven fabrics (0.5 to 6 yards per minute) and knit fabrics (2 to 16 yards per minute).
Hydroentangled Nonwoven Fabrics
Here the fibers are bonded together by mechanical bonding (fiber entanglement), which provides fabric strength. The fabrics used for Richmond Dental and Medical sponges are produced using high-pressure water jets to entangle a web of fibers; no other binders are used. Under the fiber web is a forming belt that supports the web as it passes under the water jets. The shape of the belt produces the perforations, which results in the fabric taking on an open gauze shape. Because of the high energy of the water, any dust or short fibers are removed. This is why hydroentangled nonwoven fabrics have lint-free properties. In the case of cotton sponges, Barnhardt Purified Cotton™ is used, and therefore the fabrics produced require no further purification.
Woven fabrics for gauze are produced on a loom, which joins two sets of yarns by weaving one set between the other. The two sets of yarns are perpendicular to each other. One set is called the warp, and runs the length of the fabric. The loom will raise some of the warp yarns up and some down, creating a shed. The fill or weft yarn is placed in the shed perpendicular to the warp yarns and the shed closes, interlacing the fill yarn. In gauze fabrics there only a few yarns of warp and fill per inch of fabric. This creates the openings or spaces between the yarns in the fabric. Woven gauze fabrics are then purified to remove the natural oils, waxes, and color, making the fabric absorbent and white.
Fibers Used in Richmond Dental and Medical
Only cotton is used in both woven sponges. In the nonwoven sponge category there are all-cotton (biodegradable) sponges, as well as a polyester/rayon blend sponges.
What Properties Do Different Fibers Provide?
When wet, cotton fibers have the unique property of being stronger; however, rayon becomes weaker when wet. Polyester is non-absorbent, so its strength does not change when wet. Since polyester is stronger, it is used in the rayon blend to provide greater wet strength. Keep in mind both rayon and cotton will biodegrade. Our all-cotton sponges are 100% biodegradable.
Nonwoven Vs. Woven Sponge Absorbency Properties
As mentioned earlier, nonwoven sponges are lint-free, while woven fabrics are non-linting and can have fiber. Nonwoven fabrics have more space between the fibers; these spaces act as reservoirs to store liquids, thus having a higher absorbency capacity. Because the fibers in a woven fabric are tightly spun into yarn, there is less space between the fibers for liquids to be held. Naturally the more “plys” (layers) in a sponge (nonwoven or woven), the higher the absorbency capacity.
Hopefully this answers most of your questions about sponges. However, if you'd like more detail, request our Sponge Guide to learn even more.