Tablet Lubricant · Capsule Excipient · E470b
Magnesium stearate, the most widely used lubricant for tablets and capsules, typically added at 0.25–1% w/w. Supplied in IP, BP, USP-NF and EP grades by Chelora Pharmachem, Mumbai, and delivered across India with a batch COA and SDS.
How Buying Works
Send the quantity, grade (IP, BP, USP-NF, EP or technical), vegetable source if needed, city and date. Quote CAS 557-04-0 so there is no confusion.
Price, lead time and packing in one reply, with the specification, COA and SDS/MSDS for your QA team to review.
Samples can be arranged for QC testing, blending and compression trials and vendor qualification before your commercial order.
Packed, labelled and sent with invoice, batch COA and transport documents. Repeat orders are planned with you.
Product Overview
Magnesium Stearate (magnesium octadecanoate, magnesium distearate; CAS 557-04-0) is the magnesium salt of stearic acid and the most widely used lubricant in tablet and capsule manufacture. It is a very fine, light white powder that feels greasy and sticks to the skin. Commercial material is not a single compound: pharmacopoeias define it as a mixture of magnesium salts of fatty acids, mainly stearate and palmitate, with magnesium content of 4.0–5.0% on the dried basis.
Added at low levels, typically 0.25–1% w/w, it stops granules sticking to punches and dies and lets tablets eject cleanly. Because it is hydrophobic, too much of it, or blending it too long, can give softer tablets and slower disintegration and dissolution. Beyond pharma, it is a food additive (E470b) used as an anti-caking agent and release agent in pressed mints, a texture and adhesion aid in cosmetic powders, and a release agent and lubricant in plastics and rubber processing.
As a chemical supplier in Mumbai, Chelora Pharmachem supplies pharmacopoeia-grade and technical-grade magnesium stearate to tablet, capsule, nutraceutical and cosmetic manufacturers across India, with a batch-wise COA, SDS/MSDS and specification. Vegetable-source grades can be offered on request, subject to availability, and we can match your specific surface area or particle-size requirement where a producer offers it. From trial lots to regular bulk supply, we also supply Microcrystalline Cellulose (MCC), the filler-binder it is most often blended with in direct-compression tablets.
In Depth
Magnesium stearate is a metallic soap: one magnesium ion balanced by two long-chain fatty acid anions. In practice the fatty acid part is a blend, mainly stearic acid (C18) and palmitic acid (C16), which is why pharmacopoeias set limits of at least 40% stearic acid and at least 90% stearic plus palmitic acid. It exists in anhydrous and hydrated forms, which can change how it lubricates.
During blending, its fine, plate-like particles spread over granule and powder surfaces as a thin film. This film cuts friction between the tablet and the die wall, so tablets eject cleanly, and stops material sticking to punch faces. The same film is hydrophobic, so excess magnesium stearate or long, high-shear blending can lower tablet hardness and slow disintegration and dissolution.
It is made either by reacting stearic acid, or a mixed stearic and palmitic acid feed, directly with magnesium oxide, hydroxide or carbonate at elevated temperature, or by precipitation: a sodium stearate solution is treated with magnesium sulphate or magnesium chloride. The fatty acids come from vegetable oils such as palm, or from animal fats, and the product is washed, dried and milled to a fine powder.
Magnesium stearate is normally the last ingredient added, blended for a short, fixed time just before compression or capsule filling. Typical levels are 0.25–1% w/w, occasionally higher. Formulators validate both the level and the blending time, because over-lubrication can cause soft tablets, capping and slower dissolution, and results can change when a process moves from lab scale to commercial blenders.
Confirm the grade (IP, BP, USP-NF or EP) and the source, vegetable or animal, with any TSE/BSE statement your QA team needs. Then compare magnesium content, stearic and palmitic acid composition, loss on drying, acidity or alkalinity, chlorides, sulphates, microbial limits and, where relevant, specific surface area or particle size. Keep to one approved source where possible, and ask for the batch COA and SDS.
Chelora Pharmachem supplies magnesium stearate (CAS 557-04-0) from its centralized sales office in Mumbai to tablet, capsule, nutraceutical, cosmetic and industrial manufacturers across India. Share the grade, source preference, quantity, packing and delivery location, and our team replies with price, lead time and documents, from trial lots for formulation work to regular bulk supply for commercial batches.
Global Sourcing
Our focus is the Indian market. When local supply is short, or you need a specific origin, vegetable source or pharmacopoeia grade, our international sourcing desk brings magnesium stearate in from trusted producers abroad, and our Mumbai team handles import, documents and delivery to your plant.
Product Profile
The identifiers and properties purchase and QA teams ask for first. Batch values are always confirmed on the COA.
Identity
EC 209-150-3. Also sold as magnesium octadecanoate or magnesium distearate; E470b in foods.
Two C₁₈ stearate chains, each ending in –COO⁻, balanced by one Mg²⁺ ion.
Appearance
Very fine, light white powder with a faint fatty odour. Greasy to the touch and sticks to skin.
Solubility
Practically insoluble in water, ethanol and ether. Slightly soluble in warm benzene and warm ethanol.
Technical Data
Reference data for Magnesium Stearate, useful when writing a specification, checking an SDS or planning storage and transport.
| Property | Value |
|---|---|
| IUPAC name | Magnesium octadecanoate |
| Synonyms | Magnesium distearate, stearic acid magnesium salt, magnesium salts of fatty acids (E470b; INS 470(iii)) |
| CAS number | 557-04-0 |
| EC number | 209-150-3 |
| PubChem CID | 11177 |
| Molecular formula | C36H70MgO4, written as Mg(C18H35O2)2; idealised formula for pure magnesium stearate |
| Molar mass | 591.26 g/mol (pure stearate) |
| Composition | Commercial grades are a mixture of magnesium stearate and magnesium palmitate: stearic acid ≥ 40% and stearic plus palmitic acid ≥ 90% of the fatty acid fraction; magnesium 4.0–5.0% (dried basis) |
| Appearance | Very fine, light white powder; greasy to the touch, with a faint odour of stearic acid |
| Melting point | About 117–150 °C for commercial material; about 126–130 °C for high-purity material |
| Boiling point | Not applicable; decomposes on strong heating |
| Density | About 1.03–1.09 g/cm³ (true density); bulk density about 0.16 g/cm³ |
| Solubility in water | Practically insoluble (about 0.004 g per 100 mL at 25 °C) |
| Other solvents | Practically insoluble in ethanol and ether; slightly soluble in warm benzene and warm ethanol |
| Hydrates | Anhydrous, monohydrate, dihydrate and trihydrate forms are known |
| Use level | Usually 0.25–1% w/w in tablets and capsules; up to about 5% w/w in some formulations |
| HS code | 2915.70 |
| Transport | Generally not regulated as a dangerous good for road, sea or air; confirm with the batch SDS |
Literature values for reference. Supplied material is tested batch-wise and reported on the COA.
Applications
Its main job is keeping tablet presses and capsule fillers running smoothly. The same lubricating, anti-caking film is used in foods, cosmetic powders and plastics.
Added at about 0.25–1% w/w in the final blend, it reduces die-wall friction so tablets eject cleanly and stops granules sticking to punch faces. Level and blending time are validated, because over-lubrication softens tablets and slows disintegration and dissolution.
Pharma excipient
Improves powder flow and slug formation in hard-gelatin and HPMC capsule filling, and is one of the most common flow and anti-stick agents in vitamin, mineral and herbal tablets and capsules. Vegetable-source grades are often preferred for supplement products.
Capsules & supplements
Listed in the EU as E470b, magnesium salts of fatty acids, it serves as an anti-caking agent and release agent. It helps pressed mints and compressed confectionery release from the die, and keeps powdered food ingredients free-flowing, within the limits of local food law.
Food additive E470b
Gives pressed powders, compacts, blushes and eyeshadows better adhesion to skin, a smooth slip and good compressibility, so pressed cakes hold together. It also improves water resistance and is used in some barrier creams and talc-free powder formulations.
Cosmetics
Works as an internal lubricant and mould release agent in plastics, with a limited role as a co-stabiliser in PVC, and as a dusting and anti-tack agent for uncured rubber. Technical grades suit these uses where pharmacopoeia testing is not needed.
Industrial processing
Quality & Compliance
Every supply is backed by the documents your QA, regulatory and stores teams expect.
COA, batch-wise
Tests, limits and results for the exact batch you receive, shared before dispatch.
SDS / MSDS
Hazards, safe handling, storage, transport and first-aid measures for Magnesium Stearate.
Technical data
Typical properties and the specification we supply against, to match with your in-house spec.
On request
Additional documents for vendor approval and audits can be arranged on request.
Safety & Handling
A short summary for stores, production and EHS teams. It does not replace the Safety Data Sheet supplied with every batch.
Generally not classified as hazardous under GHS by major supplier SDS. Some national classifications list mild eye irritation, and the fine dust is combustible. Check the SDS of the batch for the classification that applies.
Wear safety glasses, gloves and a dust mask where dust can form, and use local exhaust ventilation at charging and sieving points. Avoid breathing the dust, and wash hands after handling.
Keep containers tightly closed in a cool, dry, well-ventilated store, away from heat, sources of ignition, strong oxidising agents, strong acids and alkalis.
Fine dust can form explosive mixtures with air, so avoid dust clouds and ignition sources and earth equipment. Magnesium stearate is generally not regulated as a dangerous good for transport.
Avoid raising dust, sweep or vacuum spilled material into closed containers for disposal, and keep it out of drains and water courses. Spilled powder makes floors slippery.
PAN India Delivery
From our centralized sales office in Mumbai, we supply Magnesium Stearate to buyers in every major manufacturing cluster.
MumbaiMumbai, Thane, Navi Mumbai, Tarapur, Boisar, Pune and Aurangabad.
AhmedabadAhmedabad, Vadodara, Ankleshwar and Vapi.
HyderabadHyderabad and Visakhapatnam.
BaddiBaddi and Haridwar.
GoaPharma and chemical units across Goa.
BengaluruBengaluru and Chennai.
IndoreIndore, Pithampur and Sikkim.
Specification
A typical specification for pharmacopoeia-grade magnesium stearate (IP / BP / USP-NF / EP). Share your in-house or pharmacopoeia specification and we quote against it.
The Chemistry
Made
Stearic and palmitic acids, split from vegetable oils or animal fats, react with magnesium oxide or hydroxide, or a sodium stearate solution is precipitated with a magnesium salt. The product is washed, dried and milled to a fine, fluffy powder.
Used
It is added to the finished blend for a short, controlled mixing time before compression or capsule filling. A thin film coats the particles and lubricates the die wall; too much film, from excess or over-mixing, slows wetting and dissolution.
Tested
Each batch is reported on a COA covering appearance, identification, magnesium content, stearic and palmitic acid composition, loss on drying, acidity or alkalinity, chlorides, sulphates and microbial limits, so your QC team can release it quickly.
Stored
It is chemically stable, but it is a light, dusty powder that can pick up odours and moisture. Keep bags and drums closed in a cool, dry store away from strong oxidising agents, strong acids and alkalis, and follow the SDS.
Glossary
Terms you will meet on quotations, specifications and documents for Magnesium Stearate.
FAQ
Anything else, call +91 98191 11179 or write to source@chelorapharmachem.com.
Request a QuoteMagnesium stearate (CAS 557-04-0) is mainly used as a lubricant and anti-adherent in tablets and capsules, including vitamin and nutraceutical products. It is also a food additive (E470b) for anti-caking and die release in pressed mints, an adhesion aid in cosmetic powders, and a lubricant and release agent in plastics and rubber.
The CAS number is 557-04-0 and the EC number is 209-150-3. The idealised formula is C36H70MgO4, with a molar mass of 591.26 g/mol. Quoting the CAS number on your enquiry avoids confusion with calcium stearate, zinc stearate or stearic acid.
Yes, magnesium octadecanoate and magnesium distearate are names for the same substance, CAS 557-04-0. Note that commercial magnesium stearate is not a single pure compound: it is a mixture of magnesium salts of fatty acids, mainly stearate and palmitate, within pharmacopoeia limits on composition.
Stearic acid (CAS 57-11-4) is the free fatty acid. Magnesium stearate is its magnesium salt, a metallic soap with a much higher melting range and a very fine, greasy texture. Both are used as tablet lubricants, but magnesium stearate is more effective at low levels and is far more widely used.
Usually 0.25–1% w/w of the final blend, and occasionally up to about 5% w/w. It is blended in last, for a short and validated time. Using too much, or over-mixing, can reduce tablet hardness and slow disintegration and dissolution, so level and blending time should be fixed during development.
We supply pharmacopoeia grades to IP, BP, USP-NF and EP, as well as technical grade for industrial use, subject to availability. Vegetable-source material can be offered on request. Tell us the grade, source preference and any specific surface area or particle-size requirement when you enquire.
Keep it in tightly closed containers in a cool, dry and well-ventilated store, away from heat, ignition sources, strong oxidising agents, strong acids and alkalis. Avoid creating dust clouds. Follow the storage section of the SDS supplied with the batch.
Magnesium stearate is generally classified under HS subheading 2915.70, which covers palmitic acid, stearic acid and their salts and esters. Confirm the full national tariff code with your customs broker before import or export.
It is generally not classified as hazardous under GHS by major suppliers, though some national classifications list mild eye irritation. Like other fine organic powders, its dust is combustible. Read the SDS before handling, and use eye protection, gloves and dust control.
Magnesium stearate is generally not regulated as a dangerous good for road, sea or air transport. Always check the transport section of the SDS supplied with the batch.
We provide a batch-wise Certificate of Analysis (COA), SDS/MSDS and specifications. Additional documents for vendor qualification can be arranged on request.
Yes. We handle requirements from samples and trial lots for R&D, formulation and vendor approval up to regular bulk supply for commercial production, subject to product availability.
We supply buyers across India, including Maharashtra, Gujarat, Telangana, Andhra Pradesh, Himachal Pradesh, Goa, Karnataka, Tamil Nadu, Madhya Pradesh, Uttarakhand and Sikkim, from our centralized sales office in Mumbai.
Email source@chelorapharmachem.com or source@cheloragroup.com, call +91 98191 11179, or use the enquiry form on this page. Include the quantity, grade, delivery location and target date.
Request a Quote
Tell us the quantity, grade and delivery location. Our centralized sales team replies with competitive pricing, lead time and documentation.
