Materials
Reticulated Polyurethane Foam Explained: PPI, Open Cells and Filtration Performance
Reticulated polyurethane foam is one of the most widely specified materials for engineered foam filtration. During reticulation, cell membranes are removed from conventional PU foam, leaving a strong three-dimensional network of open cells. The result is high airflow, excellent permeability and dependable dust-holding capacity — exactly what HVAC, automotive and industrial buyers need.
What does reticulated mean?
In reticulated foam, the thin windows between foam cells are intentionally removed. What remains is an open skeletal structure that allows air or liquid to pass through while particles are captured on the cell strands.
This is why reticulated PU foam is preferred for washable pre-filters, panel filters and custom foam air filter elements — it combines low pressure drop with reusable service life.
Understanding PPI (pores per inch)
PPI describes how many pores appear along one linear inch of foam. Lower PPI grades have larger openings and higher airflow. Higher PPI grades trap finer particles but create more resistance.
- 20–45 PPI — coarser pre-filtration, high airflow, dust loading stages
- 45–80 PPI — general HVAC and industrial air filtration
- 80–110 PPI — finer filtration where efficiency matters more than free flow
Why MeshFLO specifies 20–110 PPI
Most filtration programmes need more than one grade. MeshFLO supplies reticulated polyurethane foam across 20–110 PPI so OEMs and maintenance teams can match media to duty cycle, dust load and housing design — then convert it into sheets, rolls or finished die-cut parts.
Frequently asked questions
Is reticulated foam the same as open-cell foam?
All reticulated foam is open-cell, but not all open-cell foam is fully reticulated. Reticulation removes the remaining membranes for near-complete openness (typically 97–99% open porosity).
Can reticulated PU foam be washed and reused?
Yes. Washable and reusable service is one of the main reasons buyers choose foam air filters over disposable media for many pre-filter duties.
