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Kaolin clay mask OEM/ODM manufacturing
Kaolin Clay Mask · OEM/ODM
Kaolin, also called white clay or china clay, is a naturally occurring clay whose main mineral is kaolinite — a hydrated aluminum silicate. Unlike bentonite or montmorillonite, kaolinite is a 1:1 layered mineral that does not swell in water; in a mask, kaolin powder holds oil and water on the skin surface by a physical mechanism and is then rinsed away with the dirt. Its safety record is fairly complete: of the 8 naturally sourced clays re-reviewed by the Cosmetic Ingredient Review (CIR) Expert Panel in 2023, kaolin was concluded safe in the present practices of use and concentration with no exception, while data for the other 7 were insufficient for products that may be incidentally inhaled. Efficacy evidence is limited: we have not found any human skin trial of kaolin alone, so this mask promises what can be measured on the finished product — cleansing and a fresh, unclogged skin feel — not “detox”. As a mined raw material, quality starts with the certificate of analysis (COA) for every lot: heavy metals, microbes, crystalline silica. Butter-C offers turnkey OEM/ODM manufacturing, from formulation and testing to a labeled finished product with its notification dossier.
Formula base
Kaolin as the clay body, with a humectant base
Clay-mask formats and how to blend several clays are covered on the general clay mask page; this page puts kaolin in the name. The concentrations below are maximum levels reported on the US market and compiled by CIR, not recommendations.
Kaolin — the named clay
INCI Kaolin, CAS 1332-58-7. CIR defines it as a naturally occurring hydrated aluminum silicate, approximately Al2O3·2SiO2·2H2O; CosIng functions include absorbent, bulking, opacifying and mild abrasive. 2022 survey: maximum reported concentration in paste masks 5–33%. The level in the formula is set by the desired consistency and setting time (formulation experience).
Swelling clay (optional)
Bentonite is a smectite that swells in water and is often added to keep the clay from settling; the 2022 survey lists 1.5–10% in paste masks. Kaolin, bentonite and montmorillonite are three separate INCI names with three CAS numbers — a “pure kaolin” version adds no other clay so the product name stays accurate.
Humectants and emollients
Glycerin, Butylene Glycol and Panthenol slow drying; Squalane reduces the tight feel after rinsing (formulation experience). Kaolin absorbs surface water, so leaving it on too long can feel tight and dry (kaolin article).
Stabilizer and preservative system
Xanthan Gum keeps the suspension stable and tolerates electrolytes from the clay; Phenoxyethanol with Ethylhexylglycerin forms the preservative system. Clays can retain cationic preservatives on the mineral surface, so the system is confirmed by an ISO 11930 challenge test on the actual formula.
Key technical points
Correct INCI, heavy metals, silica dust and microbes
Kaolin is mined: the crude ore carries quartz, mica and feldspar, which are reduced by screening and settling (CIR). The four items below decide whether a kaolin lot can be used.
Correct INCI, not color
“White clay”, “green kaolin” and “green clay” are common or trade names, not INCI names; a material sold as “green kaolin” may be declared as Montmorillonite (kaolin article). Butter-C checks the INCI name, CAS number and mineral identification (X-ray diffraction) on the COA rather than relying on color or trade name.
Heavy metals
CIR expressed concern about heavy metals in clays and stressed good manufacturing practice to limit impurities; in an excised human skin test (Franz cell) with three clay muds, no metals were detected passing through the skin. Fischer et al. (2025) found mercury in every cosmetic clay sample tested in Poland, with white clays averaging 52.80 µg/kg — far below the 1 ppm limit for finished products, yet the authors still recommended metal testing. The finished product must meet Annex 06-MP of Vietnam’s Circular 06/2011/TT-BYT: mercury 1 ppm, arsenic 5 ppm, lead 20 ppm (the current text to be confirmed by regulatory affairs when the dossier is prepared).
Crystalline silica and dust in the plant
According to CIR, some kaolin suppliers report crystalline silica (quartz) below 2%. The main risk is long-term dust inhalation by workers: CIR summarizes cases of kaolin pneumoconiosis in long-serving processing workers and notes that dry processing was associated with higher risk. Weighing, sieving and charging powder are done with local exhaust, dust masks and minimal pouring height; the COA states crystalline silica and particle size.
Microbes in a mineral raw material
CIR notes that bacteria in kaolin are mainly aerobic, spore-forming Gram-positive species, with no pathogenic organisms found; every lot still needs a microbial result. The finished product meets Annex 06-MP: total viable count ≤ 1,000 CFU/g, with no P. aeruginosa, S. aureus or C. albicans in 0.1 g or 0.1 ml of sample.
Three formulation directions
Three ways to place kaolin in a rinse-off mask
Pure kaolin cream
Kaolin is the main clay with no other clay blended in, Xanthan Gum holds the suspension, glycerin and panthenol slow drying. A short, accurately named ingredient list; settling and water separation need careful checks across stability time points.
Kaolin – bentonite
Kaolin forms the clay body and a small amount of bentonite gives a firmer cream. Bentonite is sprinkled into the water phase and stirred until fully hydrated before salts or alcohol are added (practice). The label lists both INCI names.
Kaolin powder mixed with water at use
An anhydrous blend the user mixes with water just before applying. Because CIR concluded kaolin is safe even in products that may be inhaled, while data for bentonite are insufficient for this form, the powder version uses kaolin only (a cautious choice). There is no water in the pack, but the finished product is still tested for microbes; directions say to mix one use at a time.
Packaging is designed with the formula
Tubes keep moisture in and are more hygienic than jars; jars need a tight liner so the mask does not dry at the edges. The powder version needs moisture-proof packaging closed after each use.
Parameters we monitor
What our R&D team measures on every sample
These are the parameters Butter-C tracks during formulation and scale-up. Specific limits are agreed with you on the approved sample and then written into the product’s in-house specification.
- Kaolin incoming check
- Lot COA: INCI, CAS, mineral identification, heavy metals, microbes, crystalline silica, particle size; rechecked before production.
- Oil absorption & suspension pH
- The sources we read give no verified values for cosmetic kaolin — measured on the actual raw-material lot and written into the raw-material specification.
- Appearance & fineness
- Color, odor, fineness, no grit; natural clay color varies between lots, so it is compared with a reference sample.
- Finished-product pH
- Measured on a diluted dispersion and adjusted to a skin-appropriate range.
- Viscosity & consistency
- Rotational viscometer or penetration test; determines spreadability and how easily the product leaves the pack.
- Heavy metals in the finished product
- Mercury, arsenic and lead per Annex 06-MP; cadmium per in-house specification.
- Stability
- 40 °C and freeze–thaw cycling; watching for water separation, clay settling, edge drying, color or odor change; weight loss checked in the final pack.
- Drying time and rinse-off
- Assessed on skin: setting time, tightness, and the water and number of rinses needed to remove it.
- Microbiology & challenge test
- Tested at a GLP / ISO 17025-accredited laboratory; preservative efficacy (challenge) test per ISO 11930 for the cream version.
Claims
Claims for a rinse-off mask named after kaolin
A PubMed search (October 2026) found no human skin trial of kaolin alone. The closest data come from one product study: 75 adults with oily or combination skin used a commercial clay mask twice a week for 4 weeks; the abstract reports improvements in sebum and stratum corneum hydration, while pore area did not change significantly; the abstract does not describe a control group or list the full composition, and the authors work for a cosmetics group (Zhang et al., 2023). The results belong to the whole formula. Butter-C reviews label and marketing wording when preparing the notification dossier.
Cleanses the skin surface
Instead of: detoxifies skin, draws out toxins, purges heavy metals.
Leaves skin feeling fresh and unclogged (sensory, tested on the finished product)
Instead of: permanently tightens or shrinks pores.
Helps skin look less shiny (only once sebum or sensory testing has been done on the finished product)
Kaolin absorbs surface oil; the sources we read do not show kaolin changing how much sebum the glands produce. Instead of: regulates sebaceous glands, reduces oil production long term.
White clay (Kaolin) — correct INCI name
Mine of origin only when the supplier has documents. Instead of: calling kaolin green or pink clay; claims about inflamed acne or acne bacteria.
Directions and reminders
State leave-on time and uses per week, avoid the eye and lip area, rinse and then moisturize; patch-test on a small area first. Industry data compiled by CIR: repeat-insult patch testing found no sensitization to a mask with 40% kaolin (51 people), while with one mask containing 14.5% kaolin, 1 of 103 people reacted with erythema, edema and papules. Instead of: non-irritating, safe for all skin types.
Pregnancy, broken skin
Pregnant or breastfeeding women: data are insufficient — ask a doctor. Do not apply to broken skin; anyone who has reacted to a clay mask before should patch-test first.
Manufacturing specifications
Available capabilities
- Texture
- Smooth clay cream in kaolin’s natural off-white, or an anhydrous powder mixed with water at use.
- Format
- Tube or lined jar; moisture-proof packaging for the powder. Volume agreed when choosing packaging.
- Minimum order quantity
- Agreed per order — depends on the formula direction and format chosen.
- Testing
- At a GLP / ISO 17025-accredited laboratory; a certificate of analysis delivered with every lot, including heavy metals and microbiology.
- Documentation
- Product Information File (PIF) and cosmetic product notification dossier prepared by Butter-C, with the kaolin COA for every lot.
- Packaging
- Label design, printing and packing run in parallel with formulation.
Suggested product concept
Fragrance-free kaolin – glycerin clay cream for combination skin
One product direction to help you picture the idea — not a ready-made product for sale. The actual formula is built around your brand’s positioning and price range.
Kaolin
The main clay body with no other clay; lot COA for heavy metals, microbes and crystalline silica.
Glycerin, panthenol
Slow drying and reduce tightness; “does not leave skin tight” is used only after sensory testing.
Xanthan Gum, phenoxyethanol system
Keep the suspension from settling; the preservative system is confirmed by an ISO 11930 challenge test.
100 ml tube, fragrance-free
Apply for the time stated on the label, once or twice a week, rinse and then moisturize.
Customization options
What you can specify
The same format can serve very different customers. Tell us your requirements in the areas below and our pharmacists will build the matching formula.
Pure kaolin or a clay blend
Kaolin only, or with bentonite for structure — a different INCI list and a different process.
Format
Rinse-off cream in a tube or jar, or an anhydrous powder mixed with water at use.
Drying and feel
Fast-setting and clearly tightening, or slow-drying and less tight — adjusted through the clay-to-humectant ratio and assessed on the finished product.
Supporting ingredients
Panthenol, squalane, glycerin — safety-assessed before being added.
Fragrance and color
Fragrance-free (recommended) or a light fragrance with fragrance allergens declared as required; kaolin’s natural off-white color.
Ingredient positioning
Vegan, paraben-free, fragrance-free — please tell us at the start so we can select suitable raw materials.
Further reading
Related knowledge
Kaolin (white clay) in cosmetics
Physical oil absorption, limited evidence, heavy metals, microbes and regulation (in Vietnamese).
Clay mask OEM/ODM manufacturing
Clay-mask formats, blending several clays and general monitoring parameters.
Bentonite in cosmetics
The swelling clay often paired with kaolin: crystalline silica and the CIR conclusion (in Vietnamese).
Mung bean clay mask OEM/ODM manufacturing
Kaolin – bentonite as the base for the traditional mung bean face-wash story.
Microbial control in cosmetics
Contamination from natural raw materials and microbial limits for finished products (in Vietnamese).
How we work
From idea to finished batch
Eight steps and three milestones signed off by both sides: approved sample, notification number, finished batch. Step-by-step details (in Vietnamese) →
Get started
Tell us about the product you plan to launch
Send us your product direction and expected volume. Our team will get back to you during business hours (Vietnam time, GMT+7).
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