Bio-Based Friction Resin & CNSL for Brake Pads

The Chemistry

Why CNSL Has Always Been in Brake Pads

CNSL's role in friction materials is not new. For decades, friction material formulators have used polymerised CNSL — known as friction dust or cashew friction particles — as a key ingredient in non-asbestos organic (NAO) brake pad formulations. It modifies the friction coefficient, reduces noise, and improves the thermal fade characteristics of the pad.

What makes CNSL uniquely suited to this application is its C15 alkyl side chain. This long, unsaturated chain gives CNSL-based components a natural thermal resilience that allows them to remain stable above 250°C — the temperature range that brake linings routinely reach during hard braking. Conventional short-chain phenolics can degrade or become brittle under repeated thermal cycling; CNSL-based components hold up.

We supply technical-grade CNSL for friction dust production, cardanol for resin synthesis, and formulated CNSL-formaldehyde resins for use as binder systems in brake pads, clutch facings, and abrasive wheels.

Cashew nut shells — source of CNSL for friction material manufacturing

Product Forms

What Elrisa Supplies for Friction Applications

We supply CNSL in different product forms depending on your formulation needs and processing setup.

Raw Material

Technical-Grade CNSL

The heat-treated oil extracted from cashew shells, rich in cardanol. Used as the starting material for cashew friction dust production — polymerising the CNSL at elevated temperature gives the solid friction particle used in NAO brake formulations.

ColourDark amber

ViscosityContact for grade

Cardanol contentTypically 60–80%

Refined

Cardanol

The primary refined derivative of CNSL. Cardanol is the direct starting material for synthesis of CNSL-formaldehyde novolac resins used as binders in brake pads and abrasive products. Also used as a reactive diluent in epoxy coating systems.

PurityContact for specification

Phenolic hydroxyl valueAvailable on request

Flash point> 200°C

Formulated

CNSL Novolac Resin

Acid-catalysed condensation product of cardanol and formaldehyde. A thermoplastic phenolic resin requiring a curing agent (hexamine) to crosslink. Used as the primary binder resin in friction pads, providing thermal resistance, dimensional stability, and adhesion to friction fillers.

Resin typeNovolac (thermoplastic)

Cure systemHexamine crosslinker

ApplicationBrake pads, abrasives

Market Drivers

Why Friction Manufacturers Are Moving Toward Bio-Based Binders

Regulatory Pressure on Phenol

Petrochemical phenol is subject to REACH restrictions in the EU and occupational exposure limits in most industrial markets. Friction material manufacturers using phenol in resin synthesis face increasing reporting and substitution pressure. CNSL-derived resins, being phenol-free by origin, offer a documented substitution pathway.

OEM Sustainability Requirements

Major automotive OEMs in Europe and North America are implementing supply chain sustainability requirements, including minimum bio-based content in purchased components. Brake pad manufacturers supplying these OEMs increasingly need documented bio-based inputs — CNSL qualifies directly.

Copper Replacement Context

The North American phaseout of copper in brake pads (SB 346 in California, Washington state legislation) has pushed friction formulators to re-examine their entire formulation. During this reformulation process, many are also reviewing binder systems — making it an ideal entry point for bio-based CNSL binders alongside NAO reformulation work.

Proven Track Record

Unlike many bio-based materials that are still in development for friction applications, CNSL has decades of established use in friction dust and novolac binders. There is extensive published literature on CNSL friction performance — buyers are not adopting an experimental material, but a well-characterised one with a long industrial history.

Buyer's Guide

Choosing a Bio-Based Resin for Friction Materials

What to check when you replace a petrochemical phenolic binder with a CNSL-based one.

Heat resistance

The binder has to hold the pad together through repeated hard braking. CNSL's C15 side chain keeps CNSL-based components stable above 250°C, where brake linings routinely operate.

Bio-based content

CNSL comes from cashew shells, an agricultural by-product, so it counts as a bio-based input for OEM sustainability requirements. It contains no petrochemical phenol.

Safety and regulatory status

Check the Safety Data Sheet for the exact grade. Novolac binders are cured with hexamine, so they still need normal handling care. Ask us for the documents your customers or regulators require.

Proven performance

CNSL friction dust and CNSL novolac binders have more than 50 years of use in brake pads. Our laboratory can test samples against your current specification before you switch.

Looking for the resin itself? See our ELRIBOND phenolic resins, including CNSL-modified grades and CNSL friction particles.

Export Markets

Where We Ship

We export technical CNSL and CNSL-derived friction material ingredients from Ghana to buyers worldwide. Buyers from these regions already source from us or have enquired.

🇪🇺

Europe

Germany, UK, Italy, France

🇺🇸

North America

USA, Canada

🌏

Asia

India, South Korea, Japan

🌍

West Africa

Ghana, Côte d'Ivoire, Benin

FAQ

Frequently Asked Questions

What is CNSL used for in friction materials?

CNSL is used as both friction dust (polymerised CNSL particles) and as the feedstock for novolac binder resins. Friction dust adds lubricity and modifies the friction coefficient; the novolac resin holds the pad together under heat. Both roles have been established in the friction industry for over 50 years.

What is the difference between technical CNSL and CNSL resin?

Technical-grade CNSL is the raw oil extracted from the cashew shell — it contains anacardic acid, cardanol, cardol, and 2-methylcardol. CNSL resin (novolac) is a processed product made by reacting cardanol (the primary CNSL derivative) with formaldehyde under acid catalysis. The resin form is what most brake pad manufacturers specify as a binder; the raw oil is the starting point for friction dust production.

Is CNSL friction material biodegradable?

CNSL-derived components are bio-based (from renewable cashew shells), which reduces the fossil carbon content of friction materials. However, crosslinked thermoset resins are not readily biodegradable. The environmental benefit is primarily in the bio-based feedstock origin — reducing reliance on petrochemical phenol and benzene-derived raw materials.

What is cashew friction dust?

Cashew friction dust is polymerised CNSL ground into fine particles. In non-asbestos organic (NAO) brake pads it modifies the friction coefficient, reduces noise and improves resistance to thermal fade.

Is CNSL resin a non-toxic resin for friction materials?

CNSL resins replace petrochemical phenol with a bio-based phenol from cashew shells. That removes one of the main regulated raw materials, but no friction binder is hazard-free: novolac resins are made with formaldehyde and cured with hexamine. Ask us for the Safety Data Sheet for the grade you are considering.

Is your friction resin SVHC-free?

Substance status depends on the exact grade and formulation. Tell us which grade you are evaluating and the regulations you need to meet, and we will send the Safety Data Sheet and supporting information for that grade.

Can I get a sample or technical data sheet?

Yes. Contact us with your specific application details — the type of friction material, your current formulation approach, and the specification parameters you need to match. We will respond with product information, available grades, and pricing details for your enquiry.

Bio-Based Resin & CNSL for Friction Materials