FIN × Permionics
Five Decades Of Membrane Science
Every FIN purifier is built around a membrane made by Permionics — the first company in India to manufacture RO, ultrafiltration and nanofiltration membranes on home soil. Not imported. Not licensed. Engineered and cast in Vadodara, Gujarat.
Four Stages:
Watch a drop become drinking water.
Every glass from a FIN purifier passes through four distinct barriers, each removing what the next one shouldn't have to deal with. Scroll to follow the water down.
PP Spun Wound Filter
Polypropylene · String woundNot the ordinary melt-blown spun cartridge everyone else fits. FIN uses a string-wound polypropylene filter, where yarn is wound around a central core in a honeycomb pattern. That gradient structure gives it larger void spaces — and therefore a far greater dirt-holding capacity than a standard spun filter of the same size.
Coconut Shell Carbon
Activated carbon · Coconut shellActivated carbon made from coconut shell rather than coal. Its micropore structure is finer and more uniform, which makes it especially effective at adsorbing chlorine, dissolved organics and the compounds behind that faint "municipal" smell. It's also a renewable agricultural by-product — the shell would otherwise be waste.
CTO Carbon Block
Chlorine · Taste · OdourWhere stage two is loose granular carbon, the CTO block is compressed into a solid cylinder. Water is forced through the carbon matrix rather than around it, so contact time goes up and channelling goes down. This is the stage that decides whether your water actually tastes like anything.
Axiom AX Membrane
Ultrafiltration · 0.01 µm · Silver impregnatedThe Permionics hollow-fibre ultrafiltration membrane — silver impregnated, so the membrane surface itself resists microbial growth between uses. At 0.01 micron, the pores are a physical barrier: bacteria, viruses and cysts cannot pass. Dissolved minerals are far smaller, so calcium and magnesium go straight through.
Wound
Nearly every purifier on the market opens with a melt-blown spun cartridge — it's cheap and it works. FIN specifies a string-wound cartridge instead. The difference shows up in how long the filter keeps working before it chokes.
Melt-blown spun
- Structure Fine mesh of melted, blown thermoplastic fibres around a core
- Strength Efficient at capturing fine particles
- Dirt capacity Uniform collection through the matrix — fills evenly, then blocks
- Best suited to Pre-filtration ahead of RO, chemical filtration
PP string wound
- Structure Yarn wound around a core in a honeycomb pattern, forming a gradient
- Strength Excels at larger particles and sediment; robust in tough conditions
- Dirt capacity Greater — larger void spaces hold more before restricting flow
- Best suited to Real Indian supply: sediment-heavy municipal and well water
| Parameter | String wound (FIN) | Melt-blown spun |
|---|---|---|
| Construction | Layers of wound string fibres around a core | Fine mesh of melted, blown fibres |
| Fluid path | Water flows through winding spaces between strings | Water passes through the fine fibre mesh |
| Dirt-holding capacity | Greater — larger void spaces | Uniform collection through the matrix |
| Sediment removal | Effective on larger particles and sediment | Efficient on fine particles |
| Durability | Robust; withstands tough conditions | Handles up to about 80 °C |
| Practical effect | Holds more silt before flow drops off | Blocks sooner on sediment-heavy supply |
Comparison of filter cartridge types per published industry filtration guidance. Filter life in any installation depends on input water quality and usage.
Axiom
Stage four is where purification actually happens. The Axiom AX is a silver-impregnated hollow-fibre ultrafiltration membrane developed with Permionics — sized to stop every pathogen and let every mineral through.
Thousands of microscopic straws
The cartridge is packed with hollow polymer fibres. Water enters from outside each fibre and passes through its wall into the hollow centre — an enormous filtering surface folded into a small cartridge.
The membrane defends itself
Silver is impregnated into the membrane material itself, not coated on. Silver ions inhibit microbial growth on the membrane surface between uses — which matters most when a purifier sits idle overnight or over a weekend.
Small enough to stop a virus
Bacteria measure around 1 micron and most waterborne viruses around 0.02. At 0.01 micron the membrane is a physical wall to both. Dissolved calcium and magnesium ions are orders of magnitude smaller — they pass straight through.
No pump, no chemicals, no reject
Ultrafiltration runs on the pressure already in your line. Nothing is added to the water, nothing is electrically forced through it, and unlike RO there's no reject stream running to the drain.
Spectrum
Membranes are defined by pore size. Go too coarse and pathogens pass through. Go too fine and you strip out the minerals your body needs. Ultrafiltration sits exactly where it should.
Microfiltration (MF)
Catches suspended solids and larger bacteria. Too coarse to stop viruses reliably.
Ultrafiltration (UF)
Blocks bacteria, viruses and cysts as a physical barrier — while dissolved minerals pass straight through, untouched.
Used in FINNanofiltration (NF)
Begins removing dissolved salts and divalent ions. Used industrially for dye desalting and selective separation.
Reverse Osmosis (RO)
Removes almost everything dissolved — including the calcium and magnesium your body needs, and roughly three litres wasted per litre made.
Pore sizes are indicative ranges for each membrane class. A micron (µm) is one-thousandth of a millimetre.
Beyond
The membranes in your kitchen come from a company that filters antibiotics, dairy and dye effluent for industry. That's an unusual pedigree for a home appliance.
Antibiotic concentration
India's first indigenous membrane system was supplied in 1980 to concentrate a dilute streptomycin solution for a Baroda chemicals manufacturer.
Milk & whey processing
Membrane systems for milk concentration and whey fractionation — separations far more delicate than drinking water.
Dye desalting
The PERMA nanofiltration membrane became the industry solution for desalting and concentrating reactive dyes, exported to four countries.
Broth clarification
Fermentation broth clarification and enzyme purification — including India's first papain UF system.
Wastewater recycling
Zero liquid discharge and effluent recycling systems, including a 20 MLD plant running 24×7 at 85% recovery in Gujarat.
Seawater to drinking water
Membrane systems spanning the full range from broth clarification to seawater desalination — over 3,000 installations.
Industrial applications and milestones as published by Permionics Membranes Pvt. Ltd.
Five decades of membrane science,
sitting on your kitchen counter.
FIN Mini brings Permionics ultrafiltration home, tankless, mineral-retaining, zero wastage, zero power.
Meet FIN Mini