Technologies

Using different technologies, Neenah Gessner produces special papers and nonwovens. On our paper machines, we produce wet-laid nonwovens while, on our meltblown machines, we make dry-laid, fully synthetic micro-fibred nonwovens. Impregnation and coating lines allow us to add special properties using water- or solvent-based systems. Our lamination line uses different bonding technologies and supports the further specialisation of our media.

In our own research and development centre, and using our own expertise, experience, know-how and new ideas, we develop solutions for our technical media based on cellulose, synthetics and nonwovens, all of which are used in many diverse applications.

 

Laboratory

In the laboratories of our research and development centre, we carry out tests on our media according to the latest norms and standards. As part of our quality management system, tests and checks are continually undertaken.

 

Wet-laid process

Using inclined and flat wire paper machines, we produce a further range of products - technical special papers. Alongside selected cellulose fibres, we use synthetic, glass or carbon fibres to give further special properties, such as strength.

With creping technology, we can achieve different surface characteristics, from very fine to very rough crepe profiles, and with various stretch properties.

Depending on requirements, we can produce weights of 18 – 250g/m² and air permeabilities of 1 – 2000 l/m²/s.

 

Impregnating & Coating

Neenah Gessner impregnates its special technical papers using the Kiss Coat process based on methanol or, in a size press, based on water. Impregnating with phenolic, epoxy, acrylic resins or latex gives high strength, dimensional stability and improves resistance to solvents, chemicals and high temperatures.

Special additives, depending on need, can be added to give further functionality. For example, hydrophobic, hydrophilic or oleophobic properties, flame retardancy, various colours, UV stability, bactericides, fungicides, etc, can all be built-in.

Using two further coating devices [air knives], we can add still further functionality.

 

Meltblown Nonwoven

Meltblown technology is one of the most effective ways to make very fine, highly efficient filter media. A meltblown fibre has a diameter of less than 10µm, many times finer than a human hair, which has a diameter of 120µm, or a cellulose fibre of about 50µm.

The raw material is a thermo-plastic synthetic material which is melted and forced through an extruder consisting of a very large number of tiny nozzles. Immediately after exiting the nozzles, the individual filaments are blown by hot air in the same direction while still in their semi-melted state, extending them and creating very fine, endless fibres, within a few milliseconds.

Using this dry-laid process, Neenah Gessner can produce media with weights from 10 – 300g/m².
Alternatively, the meltblown can be directly applied to a carrier media [cellulose or spunbond], producing combination media in one step.

 

Nanofibers

The production of nano-fibres is a coating process in which all kinds of substrates [cellulose, spunbond or meltblown] can be coated. Because of the extremely fine fibre diameters involved, countless fibres are coated which often total just a few grams per m².

Because of their excellent release characteristics, nano-fibres can be used on the upstream side of pulse jet filters for pulse jet applications.

Almost no pressure drop and a significantly higher particle efficiency are the main advantages of the nano-fibre process, which we’ve been developing since 2004. This allows us to achieve better re-cleanability and longer filter life in filter elements.

 

Laminating

Neenah Gessner’s lamination line is capable of combining substrates such as paper, wet- or dry-laid nonwovens and films, as well as any combination of these, into a final multi-layered material.

Two bonding technologies and a finely adjustable web tension system allow us to process many light weight materials, as well as substrates with high stretch.

An ultrasonic bonding system with its dot-array pattern is used to bond up to four layers in one process step. Alternatively, the adhesive unit can spray either hotmelt adhesive or reactive hotmelts for a full-surface lamination of two layers in one process step.