Water-Repellent, Oil-Repellent and Anti-Static Finishes Explained

Why these three keep appearing in tender specs

Fire retardancy, anti-microbial and moisture control get most of the attention, and they have their own page in fire-retardant, anti-microbial and moisture-control finishes. A second cluster shows up just as often in industrial and hospitality tender documents and gets far less explanation: water-repellent, oil-repellent and anti-static.

They travel together for a reason. Water repellency and oil repellency are usually delivered by the same family of surface chemistry, and anti-static is asked for on the same polyester-rich fabrics that the other two are applied to. All three are surface properties. None of them changes the blend, the weave or the weight of the cloth, which means none of them is visible on a swatch and all of them need a test result behind the claim.

Water-repellent: not the same as waterproof

A water-repellent finish lowers the surface energy of the cloth so water beads and rolls off instead of spreading and soaking in. The fabric still breathes, and the weave still has spaces between the yarns. Under sustained rain or pressure, water gets through. Waterproof is a different product built with a membrane or coating, and a uniform fabric quoted as water-repellent should never be sold into a job that needs waterproof.

The standard proof is a spray test. A specimen is mounted in a hoop, water is sprayed onto it under set conditions, and the wetted pattern is compared against a rating chart. AATCC TM22 and ISO 4920 run near-identical apparatus and procedure under different scoring scales, so a report is only readable if it names which one was used. Ask for the method and the rating, not the phrase.

Repellency is also the property that fades fastest. Every industrial wash cycle abrades and strips the surface treatment, and many finishes need heat to re-orient after washing. A rating measured on a fresh sample tells you nothing about month six. Ask for the rating after a stated number of wash cycles.

Oil-repellent: a numbered grade, not a yes or no

Oil repellency is tested by placing drops of a series of hydrocarbons of different surface tensions on the fabric and watching for wetting and wicking. AATCC 118 and ISO 14419 are technically equivalent. The grade is the highest numbered test liquid that does not wet the surface, running up an eight-point scale, so a higher number means a harder-to-repel oil was still beaded off.

This matters for kitchen, engineering, workshop and fuel-handling roles, where the stain that ruins a garment is oil, not water. It matters less than buyers assume for general office or school programmes. Where it does apply, specify the grade you need rather than the word, because a grade 2 and a grade 6 are both truthfully oil-repellent and behave nothing alike on a workshop floor.

The same test is also how a lab detects whether a low-surface-energy finish is present at all, which is a useful check when an incoming lot is suspected of having missed the finishing line.

Anti-static: charge on the surface, measured as resistance

Polyester holds electrical charge. In dry air it accumulates on the surface of the cloth and discharges into whatever the wearer touches, which is a nuisance in an office, a genuine problem around electronics assembly, and a hazard in some fuel and solvent environments. Because our fabric and most uniform suiting is polyester-rich, this comes up on tenders far more than it does on cotton programmes.

The usual measurement is electrical surface resistivity. A specimen is placed between electrodes, a set voltage is applied and the resistance is read after a fixed dwell, under AATCC 76. The higher the surface resistance, the more charge the fabric will hold, so a genuine anti-static claim is a number that falls below a stated ceiling, not a description. A separate cling test, AATCC 115, measures the practical consequence instead, how long a charged fabric clings to an inclined metal plate.

There are two routes to get there, and the difference is the whole story on durability. A topical antistat works by holding a trace of moisture at the surface, so it depends on ambient humidity and washes off over time. A conductive fibre knitted or woven into the cloth as a fine grid is a structural property that does not wash out. If a specification matters, ask which route the mill means and test the fabric conditioned at the low humidity your site actually runs at, not at lab-comfortable conditions.

One note on vocabulary, because it decides whether a buyer finds an answer at all. The tests named above are the American ones, and they are what an Indian mill will normally quote. A European or Gulf tender written to European standards asks instead for EN 1149, a series rather than a single test: one part covers surface resistivity, another covers charge decay, and the requirements part is the one a garment standard references. The property being argued about is the same property; only the document number changes. So if a specification says EN 1149 and a mill answers with a surface resistivity figure under AATCC 76, neither party is being evasive, but the submission still does not meet the document as written, and someone has to decide whose method the acceptance limit belongs to before cloth is woven.

Where that series gets used matters more than the number. EN 1149 is referenced by protective clothing standards for work in explosive atmospheres, and clothing for that use is a certified garment with a tested material behind it, not a length of treated suiting. We do not supply fabric for that application, we hold no anti-static certification and we will not tick a box we cannot evidence. If a tender is quoting EN 1149 because the site is an electronics assembly floor, that is a conversation worth having about which route and which limit. If it is quoting it because the site has an explosive-atmosphere classification, the right supplier is a certified protective clothing manufacturer, not us.

The three side by side

None of these are self-certifying, and a logo on a brochure is not a result. The pattern is the same as with how we test our fabric: a named method, a number, and the conditions the number was produced under.

Ask what chemistry the repellency uses

Water and oil repellency have historically been built on fluorochemical finishes, and that chemistry is now the subject of tightening limits. The OEKO-TEX STANDARD 100 limits effective 1 June 2026 cut the permitted PFOS level sharply, covered in what OEKO-TEX's 2026 rules mean. Non-fluorinated repellents exist and are widely used, and they generally perform well on water and poorly on oil, which is exactly the trade-off a buyer needs told to them before the order, not after.

If your programme exports into the EU, or if your own customers publish a restricted substances list, ask the mill to state the chemistry class in writing. A repellency grade with no chemistry statement behind it is a compliance question you have deferred rather than answered.

The EU deadline on 10 October 2026

One restriction has a date close enough to matter to an order being placed now. Commission Regulation (EU) 2024/2462 added PFHxA, its salts and PFHxA-related substances to entry 79 of Annex XVII of REACH. The limits are 25 ppb for PFHxA and its salts and 1,000 ppb for related substances, both measured in homogeneous material, which for a finished cloth means the finish cannot be treated as diluted across the garment.

The dates are staged. Textiles, leather, furs and hides in clothing and related accessories intended for the general public are caught from 10 October 2026. Other consumer textiles, the upholstery and curtain and carpet band, follow on 10 October 2027. The regulation carves out personal protective equipment in risk category III, medical devices, in vitro diagnostic devices and construction textiles.

Read the scope carefully before assuming either that you are caught or that you are not, because the hinge is whether the article is placed on the market for the general public and whether it is PPE. A high-visibility jacket certified as category III PPE and a plain repellent-finished corporate blazer are not in the same position, and a uniform issued to a workforce is not obviously the same as a garment sold at retail. That is a question for your importer and your own compliance advisers against the specific article, not one a fabric mill can settle for you.

What a mill can do is tell you the chemistry class before the order. Ask for the finish to be stated in writing, and for confirmation that it is non-fluorinated where your programme needs that. Note also where the work happens: our finishing runs through partnered processing houses in the Bhilwara cluster rather than in-house, so a chemistry commitment is one we take up with the processing house at the order stage, which is another reason to ask before the lot is booked rather than after.

How to write it into a specification

• Name the test method and the acceptance number, for example a spray rating under AATCC TM22 or ISO 4920, not the phrase water-repellent on its own.
• State the number of wash cycles the result must survive, and say whether those are domestic or industrial cycles, because institutional laundering is considerably harsher.
• For oil repellency, state the grade you require on the eight-point scale rather than asking for the property.
• For anti-static, state the resistivity ceiling and the humidity the test is conditioned at, and ask whether the effect is topical or from a conductive fibre.
• Ask whether the tested result applies to the finished fabric as delivered, and whether re-finishing after wash is assumed anywhere in the claim.
• Confirm the chemistry class used for any repellent finish, and check it against whatever restricted substances list your programme is bound by.

What Benny Cotts offers today

We weave at our own unit in Atoon, Bhilwara, and our dyeing, processing and finishing runs through partnered processing houses in the region. Our standard lines are wash-fast, wrinkle-resistant poly-viscose built for durability and easy care across institutional, industrial and hospitality programmes.

We do not stock fabric carrying a water-repellent, oil-repellent or anti-static treatment as an off-the-shelf line, and we will not tick a tender box for a property we cannot hand you a test report for. If one of these three is a real requirement in your programme, the useful conversation is about volumes, shades and what is realistic through our processing partners. Request our catalog and raise the requirement with the enquiry so it is on the table from the start.

FAQ

Frequently asked questions

Does the EU PFHxA restriction affect repellent-finished uniform fabric?

It can, depending on the article. Commission Regulation (EU) 2024/2462 sets 25 ppb for PFHxA and its salts and 1,000 ppb for related substances in homogeneous material under entry 79 of REACH Annex XVII. Textiles in clothing and related accessories for the general public are caught from 10 October 2026, other consumer textiles from 10 October 2027, with carve-outs for category III PPE, medical devices, in vitro diagnostic devices and construction textiles. Whether a given uniform article falls inside the general-public scope is a question for your importer and compliance advisers, so ask the mill for the chemistry class in writing and settle scope on your own side.

Does Benny Cotts supply water-repellent, oil-repellent or anti-static fabric?

Not as a stocked line. Our standard poly-viscose is wash-fast and wrinkle-resistant, with no repellent or anti-static treatment. If your programme needs one of the three, raise it with the enquiry so we can tell you honestly what is realistic through our processing partners rather than have you order against an assumption.

Is water-repellent fabric waterproof?

No. Water-repellent means water beads and rolls off a breathable woven fabric. Sustained rain or pressure will still push water through, because the weave has spaces between the yarns. Waterproof requires a membrane or coating and is a different product entirely.

How long do these finishes last through industrial washing?

It depends on whether the effect is topical or structural. A surface treatment for repellency or a humectant-type antistat degrades with repeated washing, and repellency in particular often needs heat to re-orient after each wash. A conductive fibre woven into the cloth does not wash out. Always ask for the result after a stated number of cycles rather than on a fresh sample.

What number should I ask for on an anti-static specification?

Ask for a surface resistivity ceiling under AATCC 76, together with the relative humidity the test was conditioned at. Resistivity readings move a great deal with humidity, so a result produced in comfortable lab conditions can mean very little on a dry site in winter.

Why are water and oil repellency usually quoted together?

They are commonly delivered by the same low-surface-energy finish, and the oil test is also the standard way a lab detects whether such a finish is present at all. That said, non-fluorinated repellents typically handle water well and oil poorly, so do not assume one grade implies the other. Ask for both results if you need both.

Do these finishes change how the fabric looks or feels?

They are not visible on a swatch, but a repellent finish can slightly stiffen the handle and can affect how a fabric takes print or embroidery, since the same low surface energy that repels water also resists adhesives and some inks. If your programme is decorated, test the decoration on treated cloth before committing.