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Zinc pyrithione (ZPT) shampoo OEM/ODM manufacturing
Zinc Pyrithione Anti-Dandruff Shampoo · OEM/ODM
Zinc pyrithione (INCI: Zinc Pyrithione; ZPT) is a complex of zinc and pyrithione that exists as particles almost insoluble in water, and it has been used in shampoos for decades to remove dandruff and help reduce visible flakes. The evidence is moderate: there are trials against the same shampoo without ZPT and a pooled analysis of 17 half-head studies in Asia (2,088 people) using a 1% ZPT shampoo, but most of the work was done by companies. What sets a ZPT shampoo apart from other anti-dandruff shampoos is the particle form: results depend on how much of the active the shampoo base leaves on the scalp after rinsing, so two products at the same 1% can perform very differently. Rules also differ by market: ASEAN allows up to 1.0% in rinse-off hair products, the US places ZPT dandruff shampoos under an over-the-counter drug framework, and the EU has banned ZPT in cosmetics since March 1, 2022. Butter-C offers turnkey OEM/ODM manufacturing for the Vietnamese and ASEAN markets, from formulation, particle suspension and ZPT assay of every batch to labeled finished goods and the notification dossier; products for the EU use a different active.
Formula base
ZPT particles, a suspending system, the cleansing base and cationic polymers
ZPT is not dissolved but suspended in the shampoo; the rest of the formula decides whether the particles stay evenly spread in the bottle and remain on the scalp after rinsing.
Zinc Pyrithione: raw material and COA
CAS 13463-41-7, C₁₀H₈N₂O₂S₂Zn, 317.7 g/mol (PubChem; SCCS 2020). Water solubility at 20 °C is only about 4.93 mg/L; the raw material is usually an aqueous dispersion containing 24–26% ZPT, so “1% ZPT” must be converted using the % on each batch certificate of analysis (COA): a 25% material needs about 4 g per 100 g of shampoo. ZPT is not in Butter-C's current raw material list: sourced per order, COA required.
Suspending system
A structuring polymer with a yield point, for example a thickening grade of Acrylates Copolymer (neutralized as per its TDS), keeps the particles from settling; Glycol Distearate gives an opaque, pearlescent base. ZPT particles make the shampoo opaque, so a crystal-clear version is hard to achieve. Particle size and shape vary between raw materials and affect how particles deposit on the scalp (Chen et al., 2018; company authors): changing supplier or particle grade means changing the formula.
Cleansing base
Sodium Laureth Sulfate with Cocamidopropyl Betaine is the familiar base for ZPT shampoos. The base does more than cleanse: in a double-blind, randomized trial in 53 people, two ZPT shampoos that differed in how much ZPT they deposited on the scalp both beat the base without active, and the high-deposition shampoo removed dandruff better than the low-deposition one (Bailey et al., 2003; company authors).
Cationic polymers and conditioning agents
Guar Hydroxypropyltrimonium Chloride and Polyquaternium-10 keep hair soft and less tangled with frequent washing and are base parameters to be tested together with the ZPT particles; Panthenol and Dimethiconol add softness. Cationic polymers and the suspending polymer are checked for compatibility in the real base.
Key technical points
Limits, deposition, particle stability and why the EU banned ZPT
These five points are where a zinc pyrithione shampoo differs from a generic anti-dandruff shampoo.
Up to 1%: a limit, not a recommended level
ASEAN Annex III (release 2026-1), Ref 101 “Pyrithione Zinc / Zinc pyrithione”: “Rinse-off hair products” 1.0%, “Leave-on hair products” 0.1%, with the condition “For purposes other than inhibiting the development of microorganisms in the product, this purpose has to be apparent from the presentation of the product”. Annex VI Ref 8 (preservative): “Hair products; 1.0 %”, “Other products; 0.5%”, “Rinse off products only. Not for use in products for oral hygiene”. A US-style 2% formula (21 CFR 358.710 allows 0.3–2% in rinse-off products under an over-the-counter drug framework) exceeds the ASEAN limit. The shampoo trials cited on this page used 1%.
Deposition drives performance
According to a review by Schwartz (2016; company author), ZPT particles deposit and stay on the skin even from rinse-off products and slowly release the active form; products with the same ZPT level often perform very differently. A randomized, double-blind trial in 620 people found that a ZPT shampoo with an optimized base outperformed a shampoo combining ZPT with climbazole at all four weekly time points (Schwartz et al., 2013; company authors; the abstract does not give the %). Butter-C optimizes the base rather than raising the active level.
Keeping particles even and chemically intact
Schwartz (2016) lists three conditions: ZPT must be retained on the skin and evenly distributed (including in hair follicles), must form a physically stable dispersion, and must stay in its active chemical form. Plant practice: settling checks after centrifugation and freeze–thaw cycling, and samples from the start, middle and end of each filling run to confirm uniform content.
Chelating agents and color
Adding 2% EDTA to a 1% ZPT shampoo converted about 17.3% of the ZPT into free pyrithione; in rats, pyrithione in 24-hour urine rose about fourfold (Jung et al., 2019). The 2% level is far above usual chelating levels (0.05–0.1%), where no data exist, so Butter-C assays ZPT before and after accelerated aging. Color change on contact with metal ions is plant experience without a verified source: purified water, stainless steel equipment, color monitoring.
Safety and why the EU banned it
SCCS opinion SCCS/1614/19 (2020) concluded that ZPT is safe as an anti-dandruff agent in rinse-off hair products up to 1%, taking exposure from other sources into account; ZPT can be a mild skin irritant and is a severe eye irritant in its pure form; its potential to cause contact allergy is low. The EU banned it from March 1, 2022 anyway (Regulation (EU) 2021/1902, Annex II entry 1670) because ZPT is classified as toxic for reproduction category 1B and it was not shown that no suitable alternatives exist; that is a hazard classification, not a risk assessment at shampoo use levels. Pregnancy or breastfeeding: human data are insufficient, so users should ask a doctor.
Three formulation directions
Three zinc pyrithione shampoo lines
ZPT alone, base optimized for deposition
1% ZPT as in the shampoo trials; sulfate – betaine base, cationic polymer, neutral feel, for daily washing. Investment goes into deposition and suspension testing rather than a second active.
Cooling ZPT for men
Menthol adds a cool scalp feel. In the pooled analysis by Collins et al. (2018; company authors), the 4-week difference between a 1% ZPT shampoo and a regular shampoo was larger in men (−17.5 adherent flake score) than in women (−11.1). The menthol level is set by sensory testing and eye irritation assessment.
Matching shampoo and conditioner
A rinse-off conditioner with ZPT also follows the 1.0% level of Ref 101; SCCS 2020 calculated separate safety margins for conditioner and for using both products. A cationic conditioner base must be checked for compatibility with ZPT particles.
Packaging designed with the formula
Opaque pump or flip-cap bottles, trial sachets. Uniform ZPT content is also checked in trial sachets (plant practice).
Parameters we monitor
What our R&D lab measures on every sample
These are the parameters Butter-C monitors during formula development and scale-up. Specific limits are agreed with you on the approved sample and then written into the product's in-house specification.
- ZPT content
- Assayed in the finished product for every batch, at baseline and after accelerated aging; reported as % pure ZPT, not above 1.0%.
- Raw material certificate of analysis
- % ZPT in the dispersion and the supplier's particle grade; a change of supplier means retesting the formula.
- Homogeneity
- No settling or separation after centrifugation and freeze–thaw cycling; even content at the start, middle and end of each filling run.
- pH and viscosity
- Measured at 25°C; the yield point of the suspending system is tracked along with viscosity.
- Color
- Color change monitored after storage at 40°C and under light.
- Microbiology and preservative challenge test
- Tested at a GLP / ISO 17025-accredited laboratory; although ZPT has an Annex VI entry, the formula still goes through a preservative efficacy test to ISO 11930.
- Efficacy assessment (if you publish figures)
- Adherent flake scoring by scalp quadrant in people with dandruff, at an independent testing facility; changing the surfactant base, polymer or particle grade after testing means re-testing.
- Eye irritation
- Pure ZPT is rated a severe eye irritant (SCCS 2020); the finished product is assessed by a method proposed by the testing laboratory, and the label says to avoid contact with eyes.
- Packaging compatibility
- Staining, pump force, residue at the nozzle and leakage are monitored.
Claims
Claims within cosmetic scope
In Vietnam and ASEAN, a ZPT shampoo is a cosmetic when its claims stop at removing dandruff and caring for the scalp. The evidence is moderate: there are base-controlled trials, large pooled data and long-term placebo-controlled trials, but nearly all were done by companies, and in people with severe dandruff (the study group also included scalp conditions outside cosmetic scope) a 1% ZPT shampoo improved less than a 2% ketoconazole drug shampoo (Pierard-Franchimont et al., 2002; a medical setting). In the US, a dandruff control claim is an over-the-counter drug claim, so US exports fall outside the scope of this page. Butter-C reviews label and marketing wording when preparing the notification dossier.
Removes dandruff, helps reduce visible flakes
Instead of: drug-like claims about dandruff, “eliminates dandruff permanently”.
Helps relieve dandruff-related itchiness (when backed by self-assessment data on the finished product)
Instead of: drug-like promises to end scalp itching.
Leaves the scalp clean and comfortable
Instead of: claims about acting on Malassezia or bacteria on the scalp, statements about seborrheic dermatitis or scalp psoriasis.
Hair stays soft, not dry, with frequent washing
Instead of: restores damaged hair.
Results after a number of washes
Only stated after testing on people with the actual formula. Instead of: comparisons with drug actives or other actives based on someone else's studies.
No hair loss statements
Appendix 03-MP does not accept hair loss or hair growth claims. Instead of: prevents hair loss, stimulates hair growth.
Manufacturing specifications
Available capabilities
- Texture
- Opaque or pearlescent shampoo, with or without a cooling feel.
- Active
- Zinc pyrithione sourced per order, with COA; piroctone olamine and climbazole are available for ZPT-free lines.
- Pack types
- Pump bottle, flip-cap bottle, trial sachet. Volume agreed when selecting packaging.
- Minimum order quantity
- Agreed per order.
- Testing
- Tested at a GLP / ISO 17025-accredited laboratory, including ZPT assay; a certificate of analysis comes with every batch.
- Dossier
- Product Information File (PIF) and cosmetic product notification dossier prepared by Butter-C, with the active's COA.
- Packaging
- Label design, printing and packing run in parallel with formulation.
Suggested product concept
1% zinc pyrithione anti-dandruff shampoo with a light cooling feel
A concept to help you picture the product, not a ready-made product for sale. The actual formula is built around your brand positioning and price range.
Evenly suspended ZPT
1% ZPT calculated from the COA in a suspending system with a yield point; ZPT assay and settling check on every batch.
A base that helps particles stay
Sodium Laureth Sulfate, Cocamidopropyl Betaine and Guar Hydroxypropyltrimonium Chloride; changing the base after efficacy testing means re-testing.
Light cooling, hair not left dry
Menthol at a moderate level; Panthenol and Dimethiconol keep hair soft with several washes a week.
400 ml bottle, regular-use directions
Opaque pump bottle; the label says to massage evenly into the scalp, rinse thoroughly, use regularly as directed and avoid contact with eyes; if contact occurs, rinse at once with plenty of water.
Customization options
What you can specify
The same product type can target very different customers. Tell us your requirements in the areas below and our pharmacists will build the formula accordingly.
Target market
ZPT can be used for Vietnam and ASEAN; EU-bound products cannot contain ZPT (banned since March 1, 2022): switch to a piroctone olamine or climbazole shampoo, with EU limits confirmed by regulatory staff.
ZPT level
Up to 1.0% in rinse-off shampoo and conditioner; we do not follow 2% formulas from the US market.
Combined actives
Climbazole (Annex III Ref 326: up to 2.0% in anti-dandruff shampoos) or Salicylic Acid (Annex III Ref 98: up to 3.0% in rinse-off hair products, not for children under three); a second active is not necessarily better than an optimized ZPT base.
Feel and user group
Peppermint cooling or neutral; men, women, long hair, oily scalp.
Other products in the line
Leave-on scalp sprays and serums allow up to 0.1% ZPT only; body washes and facial cleansers may use ZPT only as a preservative (up to 0.5%, rinse-off), without anti-dandruff positioning.
Further reading
Related knowledge
Zinc pyrithione in cosmetics
Shampoo trial table, the SCCS assessment, Annex III Ref 101, Annex VI Ref 8 and the EU ban (in Vietnamese).
Anti-dandruff shampoo manufacturing
The general page on anti-dandruff actives; this page focuses on zinc pyrithione.
Piroctone olamine shampoo manufacturing
A fully dissolved active and an option for EU-bound products.
Dandruff and oily scalp
Why the scalp flakes, what a shampoo can do and when to see a dermatologist (in Vietnamese).
Climbazole in cosmetics
An active often combined with ZPT and its two limit entries (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 →
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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