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Retinol serum OEM/ODM manufacturing
Retinol Serum · OEM/ODM
Retinol is the alcohol form of vitamin A and a skin-conditioning active with a fair number of human trials: controlled studies at 0.1–0.5% reported skin looking smoother and more even-toned after a few months, although sample sizes are small and some studies had no vehicle arm. Retinol is a precursor that the skin converts gradually, quite different from tretinoin — a prescription drug that is prohibited in ASEAN cosmetics. The hard part of a retinol serum is in the factory: retinol is practically insoluble in water, oxidized by air and degraded more by light than by heat, so quality depends on the oil or emulsion base, the antioxidants, airtight light-proof packaging and real-time retinol assays. ASEAN sets no specific concentration limit for retinol; Butter-C uses the EU level of 0.3% retinol equivalent as a cautious benchmark (mandatory for goods exported to the EU) and confirms the level by testing the finished product. The material is not in Butter-C's current stock list, so it is sourced per order with a mandatory COA. Butter-C offers turnkey OEM/ODM manufacturing, from formula development and testing to a labeled finished product and notification dossier.
Formula base
Retinol, an oil or emulsion base, antioxidants
Retinol dissolves in oil and is very sensitive to air and light — the four points below decide how much retinol is still in the serum on the last day of its shelf life.
Retinol — the alcohol form of vitamin A, not tretinoin
Retinol (INCI: Retinol; CAS 68-26-8 / 11103-57-4) is all-trans-retinol, C20H30O, molecular weight about 286.5; practically insoluble in water, soluble in alcohol, oils and fats (PubChem). Retinol is a precursor: the skin gradually converts it into retinoic acid. Retinoic acid (tretinoin) is a prescription drug and is prohibited in ASEAN cosmetics — Annex II, Ref 375 “Tretinoin (INN) (retinoic acid and its salts)”.
Sourced per order, COA mandatory
Retinol is not in Butter-C's current stock list. Commercial retinol is usually offered as a solution or premix that already contains antioxidants; the COA must state the actual retinol content, the carrier oil and any stabilizers — these go into the ingredient list. Every concentration calculation is based on actual retinol, not on the percentage of raw-material solution.
An anhydrous oil base or the oil phase of an emulsion
Because it does not dissolve in water, retinol goes into an oil base (Caprylic/Capric Triglyceride, Squalane, jojoba oil) or into the oil phase of a light emulsion. Retinol in oil solution is fairly stable, while the free alcohol is readily oxidized by air (Merck Index, cited via PubChem). Retinol is added at the cool-down stage, handled under reduced light with limited air exposure (manufacturing practice based on the material's properties).
Antioxidants, chelator and humectants
Tocopherol, BHT (Annex III Ref 342: up to 1% in “Other leave-on and rinse-off products”, counting any BHT already in the retinol material) and Disodium EDTA in water-containing versions are standard; their effect must be proven by assaying retinol over time. Glycerin, Panthenol and Sodium Hyaluronate add a moist feel and help tolerability.
Key technical points
Light, oxygen, concentration and assay
Light degrades retinoids more than heat
A survey of 16 retinoid derivatives in 12 commercial cosmetics: content fell by 0–80% after 6 months at 25 °C and from 40% to complete loss at 40 °C; light caused more degradation than temperature; some products contained less than declared. The authors recommend real-time stability studies rather than relying on accelerated testing alone (Temova Rakuša 2021).
Airtight, light-proof packaging
Airless bottles or aluminum tubes, light-blocking bottles; minimal air headspace; avoid wide-mouth jars. An amber glass dropper bottle only suits a small-volume oil version and must be stability-tested in that exact pack (formulation experience).
Concentration: no ASEAN ceiling, the EU level as a benchmark
Retinol, retinyl acetate and retinyl palmitate are not listed in ASEAN Annexes II, III or VI (06/2026 version). Regulation (EU) 2024/996 (Annex III, entry 376): up to 0.05% retinol equivalent (RE) in body lotion and 0.3% RE in other leave-on and rinse-off products; mandatory label text “Contains Vitamin A. Consider your daily intake before use”; non-compliant products may not be placed on the EU market from 1 November 2025 and may not be made available from 1 May 2027. Butter-C proposes no more than 0.3% RE as a cautious benchmark (mandatory for EU exports); the exact level is to be tested on the finished product.
HPLC assay; avoid strongly acidic bases
Retinol is assayed at the start and at each real-time stability point; if a percentage is printed on the label, it must still be true at the end of the shelf life. Retinol is less stable in acidic than in alkaline media (Remington, cited via PubChem), and high-strength exfoliating acids add to irritation — no high-strength AHA or BHA in the same bottle.
Three formulation directions
Three styles of retinol serum
Anhydrous oil-based retinol serum
Retinol dissolved in Caprylic/Capric Triglyceride and Squalane with Tocopherol and BHT. With no water phase it needs no preservative system for water, but microbiology is still tested and oil oxidation monitored. For normal and dry skin, with a short ingredient list.
Light-emulsion retinol serum
Retinol in the oil phase of a thin oil-in-water emulsion (Cetearyl Olivate, Cetearyl Alcohol), with Glycerin, Panthenol and Sodium Hyaluronate. Lighter and easier to spread than the oil version; it needs a preservative system that passes ISO 11930 challenge testing and emulsion-stability monitoring.
Low-level retinol serum for first-time users
0.1% retinol — the level used in the Tucker-Samaras 2009 and Randhawa 2015 trials (in the stabilized formulas used in those studies; the results do not transfer automatically to another formula) — with Panthenol, Allantoin and Bisabolol, fragrance-free. The label tells users to start every other night and increase as tolerated.
How it differs from existing serum pages
The anti-aging serum page combines several active groups (peptides, retinoids, vitamin C), the night cream page is a rich cream base, and the bakuchiol serum uses an active that is not a retinoid. This page is for a serum named after retinol, built around retinol's own concentration, stability and directions for use.
Parameters we monitor
What the R&D lab measures on every sample
These are the parameters Butter-C tracks 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.
- Incoming raw material file
- CAS, actual retinol content, carrier oil and stabilizers, appearance, manufacturing date, supplier storage conditions.
- Retinol assay
- HPLC at the start and at each real-time stability point at room temperature; accelerated data for reference only.
- Appearance, color & odor
- Against the reference sample at each stability point; darkening or a rancid oil odor signals oxidation and triggers a re-assay.
- Light exposure in the pack
- Light-exposure testing in the exact bottle or tube to be used; retinol content compared before and after.
- pH & viscosity
- For the emulsion version: pH per the raw-material TDS, set on the sample; pH drift, viscosity and separation tracked.
- Microbiology & preservative challenge
- Tested at a GLP / ISO 17025-accredited laboratory; water-containing versions undergo ISO 11930 preservative efficacy testing on the final formula; anhydrous versions are still tested for microbiology.
- Skin assessment
- Tolerance testing as the target market requires; to claim “skin looks smoother and more even-toned”, measure it on volunteers using the finished product itself.
- Packaging compatibility
- Filled into the exact airless bottle or tube to be used; seal integrity, full dispensing and material odor monitored.
Claims
Claims matched to the evidence for retinol
Retinol has a number of controlled human trials, but each must be read for its actual design. Kafi 2007: randomized, double-blind, vehicle-controlled, left-versus-right arm comparison in 36 elderly people (mean age 87); a 0.4% lotion applied by study staff up to 3 times a week for 24 weeks; an analysis including every randomized participant showed fine-wrinkle scores falling by 1.64 versus 0.08 on the vehicle side; the abstract does not state how many completed. Tucker-Samaras 2009: randomized, double-blind, split-face, a stabilized 0.1% cream (the abstract lists 36 subjects on retinol and 28 on vehicle), 8 weeks, women with moderate photodamage; the first author was employed by a consumer-goods company. Randhawa 2015: two 52-week double-blind vehicle-controlled studies, 62 people applying to the full face (the abstract does not mention randomization). Dhaliwal 2019: randomized, double-blind, 44 people, retinol 0.5% once daily versus bakuchiol 0.5% twice daily, 12 weeks, no vehicle arm; both improved wrinkles and hyperpigmentation with no statistical difference, and the retinol group reported more scaling and stinging. Zasada 2020: 37 volunteers, a 0.3% serum on one half of the face and 0.5% on the other, 12 weeks; the abstract does not describe randomization (although PubMed indexes it as a randomized trial), has no vehicle side (the liquid-crystal vehicle was tested separately beforehand in 28 volunteers for 8 weeks) and does not state how many completed; hyperpigmentation, unevenness and wrinkles decreased gradually on both sides, with mild to moderate irritation that was more frequent and intense on the 0.5% side. The 0.4–0.5% levels in some studies are higher than the EU limit of 0.3% RE. The wrinkle results are described so you understand the ingredient; Annex 03-MP of Circular 06/2011/TT-BYT does not accept claims to prevent, reduce or reverse age-related changes, so the label uses only the cosmetic-level claims below.
Helps skin look smoother and more even-toned (to be tested on the finished product)
Basis: the retinol research above plus assessment on volunteers using the finished product itself. Instead of: anti-aging, erases wrinkles, rejuvenates, skin renewal.
Night-time skin care; use sunscreen during the day (directions for use)
UV light inactivates retinol, and light degrades retinoids more than heat. Instead of: for day and night use with no need for sunscreen.
Contains x% retinol (when assayed)
The percentage is actual retinol and must match the assay to the end of the shelf life; EU exports add “Contains Vitamin A. Consider your daily intake before use”. Instead of: prescription-strength retinol, as strong as tretinoin, drug-like claims about acne, melasma or scars.
Directions: start every other night with a small amount on dry skin
Dryness, redness, scaling and stinging are common at the start and at higher concentrations (Zasada 2020); do not apply in the same session as AHA, BHA or benzoyl peroxide — separate by time of day or by day; if it persists or burns strongly, reduce frequency or stop and consult a dermatologist. People with sensitive skin should patch-test first. Instead of: non-irritating, use daily from day one, suits every skin type.
Note for pregnant and breastfeeding women
A multicenter prospective study of 235 pregnant women exposed to topical retinoids (in general, not retinol specifically) in the first trimester versus 444 controls found no significant differences in miscarriage or birth defects, yet the authors concluded that topical retinoids cannot be advised during pregnancy (Panchaud 2012). The serum is not positioned for pregnancy; the label advises pregnant and breastfeeding women to consult a doctor before use. Instead of: safe for moms-to-be.
Manufacturing specifications
Capabilities
- Texture
- A clear oil serum, pale yellow depending on the raw material, or an off-white fluid emulsion.
- Packaging format
- Airless bottles, aluminum tubes or light-blocking glass bottles. Volume agreed when packaging is selected.
- Minimum order quantity
- Agreed per order — depends on the formula direction, pack format and raw-material lot.
- Testing
- Performed at a GLP / ISO 17025-accredited laboratory, with a certificate of analysis for every batch; retinol assayed according to the stability plan.
- Documentation
- Product Information File (PIF) and notification dossier prepared by Butter-C, with the retinol COA and stability data.
- Packaging
- Label design, printing and packing run in parallel with formulation; the label carries evening-use and daytime-sunscreen directions.
Suggested product concept
An oil-based retinol serum for first-time users
One product concept to help you picture the result; not a ready-made product for sale. The actual formula is built around your brand's positioning and price range.
Retinol as the featured ingredient
0.1% actual retinol, sourced per order with a content COA; HPLC assay at the start and along the real-time stability plan.
Light oil base with antioxidants
Caprylic/Capric Triglyceride, Squalane, Tocopherol, BHT within the Annex III Ref 342 limit.
Fragrance-free
Removes one more source of irritation for first-time retinoid users; tolerance tested on the finished product.
Light-proof airless bottle
The label lists INCI Retinol and every component of the raw material, evening and every-other-night directions, daytime sunscreen and the pregnancy note; claims stop at “helps skin look smoother and more even-toned” after testing on the finished product.
Customization options
What you can specify
The same product type can serve very different customers. Tell us your requirements in the areas below and our pharmacists will build the matching formula.
Retinol level
Chosen by customer group and market; EU exports no more than 0.3% RE with the vitamin A warning; any level is confirmed by tolerance and stability testing on the finished product.
Oil or emulsion base
An anhydrous oil base for dry skin and a short ingredient list; a light emulsion for users who prefer a thin, non-greasy feel.
Supporting ingredients
Humectants and soothing agents (Panthenol, Allantoin, Bisabolol, Sodium Hyaluronate); no high-strength AHA or BHA in the same bottle.
Fragrance and color
Fragrance-free recommended; no added color — the pale yellow comes from retinol itself.
Packaging
Airless, aluminum tube or light-blocking bottle; clear packaging without a carton is not suitable for retinol.
Companion products
A daytime sunscreen and a gentle moisturizer in the same line, sold as a set so users follow the directions.
Further reading
Related topics
Retinol in cosmetics
Mechanism, human trials, EU concentration rules, low-irritation use and stability (in Vietnamese).
Retinal (retinaldehyde) in cosmetics
The aldehyde form of vitamin A — how it differs from retinol in metabolism, data and stability (in Vietnamese).
Light and the skin
Why retinol products come with daytime sunscreen directions (in Vietnamese).
Anti-aging serum OEM/ODM manufacturing
A different direction: a serum combining several active groups (peptides, retinoids, vitamin C).
Night cream OEM/ODM manufacturing
A different direction: a rich cream base that may contain retinol or bakuchiol.
Bakuchiol serum OEM/ODM manufacturing
A different direction: a plant-derived active that is not a retinoid.
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
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