Efficient Sub-Micron Filtration Using Unipore Surface Treatment

efficient sub-micron filtration

There are a number of filtration fabrics that successfully filter out unwanted particulates. For example, the pharmaceutical, food and chemical industries have an abundance of filtration requirements that ensure the purity and safety of their products.

Furthermore, some industrial settings need to filter sub-micron or oily particles. Historically, this has been challenging to find filtration technology that was capable of safely separating sub-micron particles. In response to this need, Filter Holdings developed the Unipore expanded PTFE (Polytetrafluoroethylene) membrane technology, which is capable of filtering products down to the sub-micron level. This post explains the many uses of the proprietary Unipore Surface Treatment technology.

The Background

Through decades of experience developing premium filter products for a variety of industrial processing operations, Filter Holdings knew there was a gap in the industry when it came to filtering sub-micron sized particles. So, they developed unique surface treatments which offer beneficial characteristics when bonded to conductive or non-conductive fabrics. This enhanced filter media was developed to solve a variety of filtration challenges including repelling water, chemical resistance, and handling oily particles.

Sub-Micron Filtration Technology

sub-micron filtration technology

Filter Holdings proprietary Unipore (expanded PTFE) membrane surface treatment was developed specifically to solve the most complex of filtration requirements. The Unipore expanded PTFE membrane produces fine uniform pores on the fabric surface that extends the filtration range down to sub-micron levels.

The Unipore expanded PTFE surface provides exceptional particle and dust release while repelling water, water-borne acids, water-borne alkali, and oils. Unipore expanded PTFE filter bags offer a high flow structure with no sacrifice in sub-micron retention. Its use of heavy duty substrates ensures a long service life in the harshest of conditions. The Unipore Expanded PTFE line is available in a wide range of woven or felted filter fabrics.

Effective on Conductive and Non-Conductive Media

The versatility of the Unipore Expanded PTFE Surface Treatment technology is especially apparent in its ability to filter materials through both conductive and non-conductive media.

Due to the insulation properties of synthetic fabrics, a static charge will build up on non-conductive fabrics rather than travel a distance to reach a grounding wire sewn over the fabric.

The pharmaceutical, food and chemical industries have long recognized the inherent dangers of using non-conductive filter media for filtering combustible powders such as starches, protein, sugars or cocoa. This awareness has reached other product processing operations potentially exposed to the risk of fire or explosion triggered by a static charge.

Along with this growing awareness, the need for static conductive filter fabrics that can handle sub-micron particle or oily particle filtration has also grown, with many industrial processing operations seeking filter media that offers superior release, chemical resistance, water resistance, and sub-micron filtration features while retaining static conductivity.

In response to industry needs, Filter Holdings’ Unipore Expanded PTFE surface membrane can be bonded to premium polyester felted and woven fabrics, with stainless steel fibers for conductivity.

Supreme Chemical Resistance

Chemically reactive or corrosive agents can range from acids to alkali, and from oxidizing agents to transition metals. Most chemical agents require a liquid medium to make contact with fibers to begin a surface attack. Filter fabrics in processing environments that involve chemically reactive or corrosive agents require a special surface finish which can limit chemical contact with the fabric fibers and block penetration to protect the fibers beneath the surface finish.

The Unipore expanded PTFE membrane fabric surface treatment offers the ultimate in fabric protection from chemically reactive agents. Applied to quality woven or felted fabrics, this surface repels water-borne chemicals, prevents surface adhesion, and is virtually immune from chemical degradation (with the exception of hydrofluoric acid).

Depending on the application and the chosen filter fabric, Filter Holdings offers a variety of filter fabric treatment options for resisting chemical agent attack and degradation:

filter fabric treatment options for resisting chemical agents
  • Acid Resistant Finish
  • Acid Resistant plus Oleophobic Finish
  • MaxClad II smooth microporous, interlayered structure

As a leading innovator of high-performance filtration media, Filter Holdings offers the widest range of specialty surface coatings and treatments for filter media specifically engineered to solve chemically reactive agent filtration issues.

Max Clad II: An Additional Small Pore Option

Filter Holdings is proud to offer multiple small-pore filtration treatments. In addition to the Unipore Expanded PTFE, the MaxClad II filter fabric surface treatment offers superior filtration. This product offers a smooth microporous and interlayered structure over the surface of felted fabric, repelling water borne chemicals and improving abrasion resistance.

MaxClad II treatment produces exceptionally fine pore sizes that improve filtration efficiency. The structure reaches deep into the felt to protect against acids, alkali or other degrading chemicals.

In short, Filter Holdings recognizes the need for broad filtration technology so that every type of filtration need can be met.

The Takeaway

When sub-micron filtration technology is necessary, Filter Holding’s Unipore Expanded PTFE Surface Treatment is the industry’s leading option. The Unipore Expanded PTFE Surface Treatment does an excellent job at repelling water, resisting chemicals and filtering sub-micron material.

Shop our Unipore Expanded PTFE surface-treated filter fabrics here, or contact the Filter Holdings team to learn more!


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