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Tea tree oil gel OEM/ODM manufacturing
Tea Tree Oil Gel · OEM/ODM
Tea tree (Melaleuca alternifolia) is native to Australia; First Nations Australians used its leaves traditionally, and the oil steam-distilled from the leaves (INCI: Melaleuca Alternifolia Leaf Oil) is now familiar in products for oily, blemish-prone skin. Tea tree is among the essential oils most studied in people: trials of a 5% gel in people with mild to moderate acne recorded a modest effect — research on an intervention for a skin condition that warrants a doctor’s assessment, not a benefit a moisturizing gel may promise. The other side is allergy: when the oil oxidizes on exposure to light, air and heat, its sensitizing potential rises. A tea tree gel therefore turns on three things: solubilizing the oil in a water gel while keeping it clear, keeping the oil from oxidizing from the warehouse to the user, and making measured claims — moisturizing, a fresh skin feel and an herbal scent for oily skin. Butter-C offers turnkey OEM/ODM manufacturing, from formulation and testing to a labeled finished product with its notification dossier.
Formula base
Tea tree oil, solubilizer, gel network and humectants
A tea tree gel is a water-based moisturizing gel that also carries an essential oil; what is specific lies in the oil’s quality, how it is brought into a water base and how it is kept from oxidizing.
Tea tree oil — know the raw material
A natural mixture of many volatile compounds without a defined chemical formula; the main constituents of commercial oil are terpinen-4-ol, γ-terpinene, 1,8-cineole, α-terpinene, α-terpineol, p-cymene and α-pinene (de Groot and Schmidt, 2016). The COA must state M. alternifolia. The raw material is in Butter-C’s current list; the label shows the INCI name Melaleuca Alternifolia Leaf Oil.
Solubilizer for the oil
Essential oils dissolve in oil, not in water; a water-based gel needs a solubilizer such as PEG-40 Hydrogenated Castor Oil or Polysorbate 20, premixed with the oil before it goes into the water. The solubilizer-to-oil ratio is set by clarity tests at room temperature and 4 °C (formulation experience).
Gel network and humectants
Neutralized Carbomer for a clear gel; Hydroxyethylcellulose or Xanthan Gum when the formula contains electrolytes. Glycerin, Propanediol, Betaine, Panthenol and Sodium Hyaluronate provide the moisturizing part — the basis of the “moisturizing” claim, not the essential oil. The solubilizer and oil can change gel viscosity and clarity, so the final thickness is set last (formulation experience).
Antioxidant and preservative system
Tocopherol mixed into the oil before solubilizing, with Disodium EDTA in the base, helps limit oxidation (plant practice; CIR advises minimizing oxidation of the oil in the final product; the report abstract names no specific measures). The essential oil does not replace a preservative: Phenoxyethanol with Ethylhexylglycerin, confirmed by an ISO 11930 challenge test.
Key technical points
Use level, oxidation, leave-on use and regulation
The four points below are where a gel with tea tree oil differs from an ordinary moisturizing gel.
No “standard” cosmetic concentration
5% is the gel level in two randomized trials in people with mild to moderate acne (Bassett et al., 1990; Enshaieh et al., 2007); a review notes that side effects were no longer minor when the oil was applied at 25% or more (Kairey et al., 2023). The sources give no standard level for cosmetics; the level in the gel is set by the safety assessment of each formula — a product left on the face all day calls for more caution than a rinse-off one.
Oxidation raises allergy risk
Oil kept where it meets light, air and warmth showed peroxides rising from below 50 to above 500 ppm within 4 days, and p-cymene rising from 2% to 11.5%; in guinea pigs, oxidized oil was 3 times more sensitizing than freshly distilled oil (Hausen et al., 1999). Practice: accept lots with a low peroxide value, split and reseal after opening, add the oil in the cool-down phase, use light-blocking packs and minimize headspace.
Leave-on use and contact allergy
Of all essential oils, tea tree oil has caused the most published allergic reactions since the first cases were reported in 1991; in routine patch testing, positive rates ranged from 0.1% to 3.5% depending on the study; most reactions came from applying the pure oil, with cosmetics responsible in a minority of cases (de Groot and Schmidt, 2016). A gel stays on the skin, so a sensitization safety assessment and a tolerance test on volunteers are mandatory before the formula is fixed.
Regulation and safety file
Tea tree oil is not named in ASEAN Annexes II, III or VI (06/2026 version): there is no specific % limit, and it does not count as a preservative (Annex VI preamble). Methyleugenol (Annex II Ref 451) is accepted only at the level naturally present in the oil and must not exceed 0.0002% in leave-on products — calculated from the COA if the oil contains it. CIR concluded that tea tree-derived ingredients are safe when formulated to be non-sensitizing, noting cumulative constituents when several botanicals are combined (Fiume et al., 2026).
Three formulation directions
Three tea tree gel lines
Clear gel with low-level tea tree oil
Oil at a low level for an herbal scent and the ingredient story, a clear carbomer base, oil-free, with humectants; claims stop at moisturizing, a fresh skin feel and fragrance — suited to mass channels.
Tea tree – niacinamide gel
Niacinamide added at 2%, the level cited on the niacinamide – zinc serum page, for oily-skin customers who want an active with human data. Niacinamide is assayed by HPLC; any shine claim is used only when measured on the finished product and belongs to the whole formula.
Light tea tree gel-cream
A small amount of light oil (squalane) with an emulsifier for dehydrated combination skin; the essential oil goes into the oil phase. An opaque white gel, not labeled “oil-free”; checked by centrifuge and freeze–thaw cycles.
Packaging is part of the formula
Opaque tubes or light-blocking airless pumps that limit air entry after each use; wide-mouth jars are not recommended. Essential oils can affect some plastics — compatibility is tested in the actual pack before it is fixed (formulation experience).
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.
- Incoming essential-oil certificate
- Gas chromatography of main constituents, peroxide value, methyleugenol per supplier data — every lot; opened lots are rechecked for peroxides over time.
- Appearance, odor and clarity
- Compared with a reference sample; watch for stale or harsh odor (a sign of oxidation), haze and separation at 4 °C, room temperature, 40 °C and under light.
- Marker constituents over time
- Gas chromatography of terpinen-4-ol and p-cymene in the finished product across stability time points — p-cymene rises as the oil oxidizes (Hausen et al., 1999); used as a reference indicator.
- pH
- Measured at 25 °C; kept within the range agreed for the gel network, preservative system and skin mildness.
- Viscosity
- Rotational viscometer at 25 °C, with spindle and speed recorded; the oil and solubilizer change the thickness.
- Accompanying active content
- Niacinamide assayed by HPLC in the niacinamide version.
- Human tolerance
- Irritation, sensitization (repeated insult patch test) and facial tolerance on the finished product at an independent test unit.
- Microbiology and challenge test
- Tested at a GLP/ISO 17025 laboratory; ISO 11930 preservative challenge test — the essential oil does not replace the preservative system.
- Packaging compatibility
- Filled into the actual tube or bottle; watch for deformation, odor change and light transmission.
Claims
Claims for a gel containing tea tree oil
Tea tree oil trials were mostly in people with mild to moderate acne: Bassett et al. (1990) — randomized, single-blind, 124 people, 5% gel versus 5% benzoyl peroxide lotion; Enshaieh et al. (2007) — randomized, double-blind, placebo-controlled, 60 people, 5% gel for 45 days; a meta-analysis of 7 studies with 445 people by Ye et al. (2026) concluded the reduction was modest. A review of 46 randomized-trial reports rated research quality as poor to modest (Kairey et al., 2023). This is a medical research setting: the results belong to the products studied and do not become claims for a moisturizing gel. Butter-C reviews label and marketing wording when the notification dossier is prepared.
Moisturizes and softens skin (from the humectants; to be tested on the finished product)
Instead of: restores or regenerates the skin.
Leaves skin feeling fresh and unclogged (sensory, tested on the finished product)
Instead of: tightening pores, deep pore cleansing.
Suitable for oily, blemish-prone skin (describes the skin type)
This describes the user, not an effect. Instead of: reducing or preventing blemishes, a spot gel for pimples, citing acne-trial figures as the product’s benefit.
Herbal tea tree scent; contains tea tree oil (Melaleuca Alternifolia Leaf Oil)
Instead of: claims to act on bacteria or fungi; “natural, so safe”; “allergy-free”.
Reduces shine on oily skin (only when measured on the finished product; a benefit of the whole formula)
The sources reviewed did not measure sebum with tea tree oil. Instead of: all-day oil control, regulating the sebaceous glands.
Label directions and reminders
Patch-test on a small area first; avoid the eyes; do not apply to damaged skin; stop using if redness or itching occurs; close tightly, keep away from light and heat; keep out of reach of children. Pregnant or breastfeeding: no specific data, ask a doctor. Many swollen, painful blemishes need a dermatologist’s assessment. Instead of: directions to dab pure essential oil on the skin.
Manufacturing specifications
Available capabilities
- Texture
- Clear oil-free gel, or an opaque white light gel-cream.
- Tea tree raw material
- Tea tree oil is in Butter-C’s current raw-material list; COA for every lot, label by INCI name.
- Pack format
- Opaque tubes, light-blocking airless pumps. Volume agreed when packaging is selected.
- Minimum order
- Agreed per order — depends on the formulation direction and pack format chosen.
- Testing
- Performed at a GLP/ISO 17025 laboratory; results delivered with every batch.
- Dossier
- Product information file (PIF) and notification dossier prepared by Butter-C, with the essential-oil COA and a sensitization safety assessment of the formula.
- Packaging
- Label design, printing and packing run in parallel with formulation.
Suggested product concept
Oil-free clear tea tree – panthenol gel for oily 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.
Tea tree oil in the name
A low level for a clear herbal scent, premixed with Tocopherol and solubilizer, added in the cool-down phase; the oil lot has its peroxide value on the COA.
Glycerin, panthenol, betaine
The moisturizing part of the gel; the “moisturizing” claim rests on testing the finished product.
Clear carbomer gel
Absorbs quickly, oil-free, suited to a hot, humid climate; morning and evening.
50 ml light-blocking tube
Opaque tube, tight cap; label directions to patch-test, avoid the eyes and close tightly.
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.
Tea tree level
Set at the outset because it decides the scent, raw-material cost and the sensitization safety file; higher levels require a more thorough safety assessment and human testing.
Accompanying active
None, niacinamide, or zinc PCA (zinc salts counted as zinc within the limit of Annex III Ref 24; electrolytes thin carbomer, so the gel network changes).
Texture
Clear oil-free gel or light gel-cream.
Additional essential oils
Each added essential oil adds to the total of sensitizing constituents (as CIR notes), so keep them few; tea tree alone is recommended.
Target market
EU export: check the EU fragrance-allergen list against the oil’s COA (limonene, for example, occurs in the oil) and the labeling threshold for leave-on products — confirmed by regulatory affairs. ASEAN Annex III has no such list yet.
Ingredient positioning
Alcohol-free, oil-free, vegan — please state these at the outset so suitable raw materials can be chosen.
Further reading
Related knowledge
Tea tree oil in cosmetics
Composition, evidence, studied concentrations and the allergy risk of oxidized oil (in Vietnamese).
Moisturizing gel OEM/ODM manufacturing
The general page on gel networks and humectants; this page focuses on tea tree oil.
Serum for oily, blemish-prone skin OEM/ODM manufacturing
A multi-active serum in which tea tree is a minor ingredient.
Tea tree oil shampoo OEM/ODM manufacturing
The same oil in a rinse-off scalp product.
Skin reactions from contact with cosmetics
Allergy and irritation from cosmetics, how to recognize them and when to see a doctor (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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