"A practical supplier guide to Capryloyl Salicylic Acid (CAS 78418-01-6, beta-LHA): what the molecule is (C15H20O4, MW 264, EINECS 417-790-1, white to almost white powder to crystal, mp 115 C, soluble in methanol, oil-compatible), why the lipophilic version reaches the sebaceous environment where salicylic acid cannot, formulation and use-level tips, handling and COA notes, and smart pairings with salicylic/azelaic acid, alpha-arbutin, kojic acid, L-ascorbic acid, glabridin, squalane, GHK-Cu, argireline, sodium lauroylsarcosinate, citric acid, vitamin A1 retinol and urea."
-Deshangchemical-chemechemi
Capryloyl Salicylic Acid (CAS 78418-01-6): The Oil-Soluble BHA That Goes Where Ordinary Salicylic Acid Can't
Salicylic acid has been a fixture in clarifying skin care for decades, but formulators keep running into the same limitation. It is water-soluble and it tends to stay at the surface in aqueous systems, which means it struggles to reach the oily sebum where clogged pores actually form. Capryloyl Salicylic Acid, catalogued as CAS 78418-01-6 and known in the trade as beta-LHA (beta-lipohydroxy acid), addresses that gap by attaching an octanoyl (capryloyl) chain to the salicylic acid backbone. The result is a lipophilic derivative that dissolves in oils and emulsions, follows the sebum into the follicle, and still delivers the keratolytic and exfoliating action buyers expect. For labs building leave-on treatments, serums, and anti-blemish products, it has become a quiet workhorse rather than a headline claim.
What the molecule actually is
Capryloyl Salicylic Acid is the capryloyl ester of salicylic acid, also documented under the name 2-hydroxy-5-octanoylbenzoic acid. Structurally it keeps the salicylic acid aromatic ring and carboxylic acid function while gaining a C8 fatty acyl group, and that single modification is what gives it oil compatibility. It behaves differently in a formula and on skin than the free acid, which is why it is listed separately from standard Salicylic acid in most raw-material catalogs.
| Property | Capryloyl Salicylic Acid |
|---|---|
| Chemical Name | Capryloyl Salicylic Acid |
| Other Names | beta-LHA; 2-Hydroxy-5-octanoylbenzoic acid |
| CAS Number | 78418-01-6 |
| Molecular Formula | C15H20O4 |
| Molecular Weight | 264 |
| EINECS | 417-790-1 |
| Appearance | White to almost white powder to crystal |
| Melting Point | 115 °C |
| Boiling Point | 454 °C |
| pKa | ~2 |
| Water Solubility | Low (29) |
| Solubility | Soluble in methanol; compatible with oily phases |
| Classification | Cosmetic raw material; fragrance; pharmaceutical intermediate |
Why formulators pick the lipophilic version
The keratolytic action of salicylic acid comes from its ability to loosen the bonds between corneocytes and to calm inflammation. Free salicylic acid is polar and hydrophilic, so in water-based systems it tends to sit on the surface. Capryloyl Salicylic Acid, by contrast, follows the sebum into the follicle, and that matters for acne-prone and combination skin where the blockage starts below the surface. Supplier technical literature reports beta-LHA at 2% improving keratin renewal and skin texture, and performing competitively against reference actives in comparative cell and clinical work. It is also valued for a gentler sensory profile than straight acids at comparable activity.
Where it goes in the formula
Because it is oil-soluble, Capryloyl Salicylic Acid is usually built into the oil phase or an oil-soluble premix and then emulsified. It pairs well with emollients such as Squalane that help carry actives into the upper skin layers, and with mild surfactants like Sodium Lauroylsarcosinate in rinse-off cleansers. In leave-on formats it is commonly combined with brightening and soothing actives such as Alpha-Arbutin, Kojic acid, L-Ascorbic Acid, and Glabridin to work on post-blemish marks, and with calming agents such as Azelaic acid for redness-prone skin.
Practical handling and spec checks
Buyers should request a COA that confirms identity (CAS 78418-01-6), appearance (white to almost white powder or crystal), and melting point around 115 °C. Confirm the grade matches the intended market, since the same CAS may be offered at different purity bands for cosmetic, fragrance, or pharmaceutical-intermediate use. Store the material in a sealed container away from moisture and strong heat; the powder tolerates normal warehouse conditions but keeps its specification best in a cool, dry place. As with any exfoliating acid, finished-product claims and use levels must follow the local regulator, and the formula should be stabilized for pH and color.
Pairing and routine logic
A typical clarifying serum might layer Capryloyl Salicylic Acid with Vitamin A1 Retinol for turnover, Argireline for expression lines, and GHK-Cu copper peptide for barrier support, while Citric Acid Anhydrous sets the pH and Urea adds humectancy. The point is not to stack actives for the sake of it, but to give each one a clear job: exfoliate, brighten, calm, hydrate. That is how a supplier-backed ingredient list reads as a finished product rather than an ingredient locker.
Use levels and formulation tips
In leave-on skin care, Capryloyl Salicylic Acid is normally used at low inclusion rates, with the exact figure set by the target market and the finished-product format. Because it is oil-soluble, the practical way to add it is to dissolve the powder in the oil phase or in a warm oil-soluble carrier before emulsification, rather than trying to disperse it directly into the water phase. It sits comfortably in the mildly acidic range that most clarifying formulas already use, and it is compatible with common emulsifiers, esters, and silicone alternatives. For rinse-off products such as cleansers and masks, it can follow the same oil-phase route or be added through a pre-dissolved concentrate. As always, run a small stability batch to check color, odor, and viscosity before scaling, and confirm that preservation holds across the planned pH window.
Sourcing and support
Chemechemi supplies Capryloyl Salicylic Acid (CAS 78418-01-6) as part of its cosmetic raw-material range, with documentation and sample support for formulation labs. The product page carries the current specification, minimum order quantity, and lead time, and our team can advise on grade selection for cosmetic, fragrance, or pharmaceutical-intermediate applications. For a quote, reach out with your intended grade and volume and we will confirm availability and COA details so your lab can start qualification without delay.
