New patterning process for flushable nonwoven substrates: Andritz has developed a process to apply special and unique artwork to flushable wipes.
A flushable wipe has to be made from fully biodegradable fibers, have adequate strength while in use, and then disperse quickly in the municipal sewage systems. Fabrics produced using Andritz wetlace technology already complied with the EDANA/ INDA flushability standards in 2011 and again in 2013, passing all seven tests according to the new guidelines. Wetlace is a technology developed by Andritz that combines wet forming and hydroentanglement. It has proven ideal for producing flushable wipes from 100% natural and/or renewable raw materials without chemical binders.
Now Andritz has developed a process to apply special and unique artwork to flushable wipes. This unique patterning process will allow wipes producers to clearly differentiate their product in ways that will resonate with consumers. This innovation was selected to be one of the 4 finalists of the INDA innovation award during the World of Wipes Conference, Minneapolis, MN in June 2014.
The patterning of flushable wipes is technically very challenging due to the weakness of the flushable substrate, which must have only enough strength for the intended purpose and then be able to disperse completely in water with no residual wet strength. The new flushable substrates patterning process benefits from the many years of experience that Andritz has in the wetlaid nonwoven industry and especially with the patterning of very light tea bag papers, which are particularly weak when wet during production.
The patterning process consists of a serigraphic printing cylinder, which rolls over the surface of the nonwoven during its production and has an injector applying very fine water jets. The water jets print the cylinder pattern onto the surface of the nonwoven substrate while it is supported by a conveyor made of a very tightly woven fabric. In this way, the integrity of the very sensitive layer of short-fiber material is preserved and the supporting, very tightly woven fabric ensures optimum fiber retention during the printing action of the water jets.
This patterning technique has been developed for use directly on continuous production lines with no impact on machine maintenance, machine cleaning and downtime. The patterns are easily interchangeable within this new process to give wipes producers maximum flexibility with their production assets.
This Andritz patterning solution is also compatible with 100% cellulose-based nonwovens, while other techniques require the use of thermoplastic fibers or chemical binders. It fits perfectly with the sustainable trend in flushable wipes, more and more of which are 100% cellulose-based and contain a majority of wood pulp fibers blended with short artificial cellulose fibers.
This powerful and innovative solution for patterning of flushable substrates allows an almost unlimited number of possible patterns. Pattern prototyping or the production of test quantities for customers' evaluation can be carried out quickly and easily in the Andritz technical centers.
By Frederic Noelle, ANDRITZ Perfojet