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Shower oil OEM/ODM manufacturing
Shower Oil · OEM/ODM
A shower oil is a clear bottle of oil with no water in it. The user applies it to wet skin under the shower: as soon as it meets water, the oil turns into a milky liquid that carries away sweat and dirt, then rinses off. That moment of "turning milky" is not a defect but the technology of the product: the emulsifier is already dissolved in the oil, waiting for water to form an oil-in-water emulsion. For people with dry skin, a softer after-shower feel is the reason to choose a shower oil over a foamy body wash. But it has to be said plainly: a shower oil is not automatically milder. In a double-blind, randomized study in healthy volunteers comparing eight shower and bath oils, some products irritated skin no more than water while others were considerably damaging, and residues left on the skin after rinsing with water were shown to impair the skin barrier (Loden et al., 2004; first author affiliated with a company). Mildness, cleansing performance and after-rinse feel must therefore be measured on the finished product itself. The technical work sits in three places: choosing emulsifiers that truly dissolve in the base oil so the bottle stays clear, keeping the oil from going rancid over the shelf life, and a slip warning for a product used in the bathroom. Butter-C offers turnkey OEM/ODM manufacturing, from formula development and testing to labeled finished goods and the notification dossier.
Formula base
Base oils, oil-soluble emulsifiers and antioxidants
A shower oil usually combines base oils, light esters and an emulsifier system large enough for the whole oil to turn milky in water. There is no water in the bottle, so no long-term emulsion stability is needed as in a lotion — what must stay stable is the clarity of the oil and its oxidative stability.
Base oils and esters
Caprylic/Capric Triglyceride (MCT oil) has a low iodine value and very few unsaturated components (CIR 2022); sunflower oil — the high-oleic type is more oxidation-stable than the high-linoleic type; sweet almond and rice bran oil for the ingredient story; Isopropyl Myristate makes the oil lighter and faster-spreading (formulation experience).
Oil-soluble emulsifiers
The group used in cleansing oils: PEG-20 Glyceryl Triisostearate, Sorbeth-30 Tetraoleate (PEG-based); Polyglyceryl-10 Laurate combined with Polyglyceryl-4 Oleate (PEG-free, less oil-soluble, so the ratio must be balanced — formulation experience). These are not in Butter-C's current raw-material data — source and COA confirmed per order.
Water-soluble surfactants: a minor part only
According to CIR, PEG-7 Glyceryl Cocoate (HLB 15) at 10% is insoluble in paraffin oil and isopropyl myristate and only disperses in sunflower oil; PEG-6 Caprylic/Capric Glycerides behaves similarly, dissolving slightly hazy in sunflower oil; Polysorbate 80 is insoluble in mineral oil. Used as a minor part, clarity must be tested in the actual oil phase.
Antioxidant and fragrance
Tocopherol is added when the oil phase is blended; fragrance dissolves straight into the oil with no solubilizer. Fragrance level follows the supplier's IFRA certificate for the rinse-off category.
Key technical points
Turning milky in water is the design — and a parameter to meet
With the same oil phase, changing the emulsifier system changes the product entirely: clear or hazy bottle, fast milky conversion or oily slicks, a clean rinse or a greasy film.
Clear when anhydrous, milky in water
The emulsifier system must dissolve fully in the base oil at low and high temperatures so the bottle stays clear, then form an oil-in-water emulsion as soon as it is mixed with water. Large amounts of hydrophilic emulsifiers often make the oil hazy or leave sediment at the bottom in the cold (formulation experience) — checked at 4 °C.
Just enough emulsifier
Too little and the oil does not fully turn milky, leaving oil slicks on skin and floor; too much and skin feels tighter and more surfactant remains after rinsing — which Loden's study (2004) showed can impair the skin barrier. The ratio is set by emulsification tests, rinse tests and tolerance assessment on the finished product.
No rancidity over the shelf life
Oils rich in unsaturated fatty acids and oleate-based surfactants readily form peroxides; Polysorbate 80 formed more peroxide than polysorbate 20 in pharmaceutical research. We choose stable oils, add tocopherol, require a peroxide value on each lot's COA and track odor and peroxide through stability time points.
Anhydrous but used in the bathroom
With no water, a preservative for a water phase is usually not needed (formulation practice), but a bottle opened under the shower can take in water from wet hands. A low microbiological risk conclusion requires an ISO 29621 assessment in the safety file; every lot is still micro-tested, and the pack limits water ingress.
Three formulation directions
Three kinds of shower oil
Unlike massage oil (left on the skin, little or no emulsifier), after-bath body oil (applied after leaving the shower area, not rinsed) and cleansing oil (for the face, removes makeup, used near the eyes), a shower oil is a rinse-off whole-body cleanser.
Clear shower oil, PEG system
MCT oil, high-oleic sunflower oil, PEG-20 Glyceryl Triisostearate with Sorbeth-30 Tetraoleate. Clear bottle, fast milky conversion, clean rinse (formulation experience, confirmed on samples); contains ethoxylated ingredients, so no "PEG-free" claim, and raw-material COAs include 1,4-dioxane.
PEG-free shower oil
Polyglyceryl-10 Laurate and Polyglyceryl-4 Oleate for a non-ethoxylated positioning. Usually needs a higher ratio, and the oil may be thicker or slightly hazier (formulation experience); Polyglyceryl-4 Oleate has a double bond and needs an antioxidant. "PEG-free" does not mean milder — tolerance is still tested on the finished product.
Named plant oil shower oil
Sweet almond, rice bran or sunflower oil as the product name. A nicer story, but a stronger base odor and more prone to oxidation than MCT oil; almond oil calls for a note for people with nut allergy. Very little oil stays on skin from a rinse-off product — no promises about the oil's components after rinsing.
Packaging is designed with the formula
Plastic bottles (avoid glass in the bathroom), flip-top or metered pump, a bottle body that is not slippery when oily, a tight closure to limit water ingress (formulation experience). No spray format, to limit oil on the floor. Compatibility testing: oils and emulsifiers can soften plastic or seep past gaskets.
Parameters we monitor
What our R&D lab measures on every sample
Below is the set of 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.
- Clarity when anhydrous
- Observed at 4 °C, 25 °C and 40 °C: no haze, no sediment, no separation of the emulsifier — the parameter specific to shower oils.
- Emulsification in water
- Oil mixed with water at a fixed ratio and procedure; time to full milky conversion, uniform opacity and oil slick after standing are recorded.
- Residual film after rinsing
- Oil left on skin and skin feel (greasy, squeaky, tight) after rinsing with water, compared with a reference sample.
- Cleansing performance
- Measured on the finished product by an in-house procedure against a reference sample; not inferred from individual raw-material data.
- Acid value & peroxide value
- Measured on incoming raw materials and on the finished product across stability time points, with rancid-odor checks.
- Density, refractive index, viscosity
- Quick identity checks that catch blending deviations between lots; viscosity sets how much oil is dispensed per use.
- Microbiology & impurities
- Tested at a GLP / ISO 17025-accredited laboratory; COAs of ethoxylated raw materials include 1,4-dioxane (finished product not above 10 ppm under the ASEAN guideline on contaminant limits).
- Stability & packaging compatibility
- Accelerated aging at 40°C, freeze–thaw cycling, light exposure; filled into the actual bottle and closure: oil leakage, plastic softening, color change, fragrance loss.
- Tolerance assessment
- Tolerance testing in volunteers with the finished product before claiming "gentle" or "for dry skin"; eye irritation assessment as required by the target market.
Claims
Claims matched to the evidence
A shower oil is a rinse-off product: its main functions are cleansing and how skin feels after the shower. Most emollients and emulsifiers in shower oils have no human trials of their own; a study comparing eight shower oils found very large differences in irritation between products. Butter-C reviews label and marketing wording as soon as the notification dossier is prepared.
Cleanses skin, turns milky on contact with water
Describes the format and its cleansing function. Instead of: claims about bacteria on the skin, detoxifies skin.
Skin feels soft, not tight, after the shower
Only when assessed in users of the finished product. Instead of: repairs the skin barrier, deep moisturizing like a cream.
Water-free oil, suited to dry skin
Describes the positioning; "gentle" or "for sensitive skin" needs tolerance testing on the finished product. Instead of: for eczema or diseased skin, non-irritating.
Contains sweet almond / rice bran oil
Describes the named ingredient. Instead of: whitening, anti-aging, nourishing skin after it has been rinsed off.
Fragrance allergens
In Vietnam, ASEAN Annex III leaves entries 67–92 blank, so there is no mandatory threshold for naming individual allergens; list "fragrance" or the full INCI. EU exports: name them above 0.01% (rinse-off) per the fragrance composition sheet.
Slip warning and directions
Oil makes floors and tubs slippery: use a small amount, rinse oil off the floor, and people with limited mobility should have assistance; not for use as a bath oil without a dedicated formula and warning. Avoid the eyes; stop use if skin turns red or itchy. The slip warning is a practice recommendation, not required by the ASEAN annexes.
Manufacturing specifications
Current capabilities
- Texture
- Clear liquid oil, colorless or with the natural tint of the base oil; turns milky in water.
- Pack formats
- Plastic bottles with flip-top or metered pump. Volume agreed when packaging is selected.
- Minimum order quantity
- Agreed per order — depends on the formula direction, emulsifier sourcing and pack format chosen.
- Testing
- Tested at a GLP / ISO 17025-accredited laboratory, with a certificate of analysis delivered with every lot.
- Dossier
- Product Information File (PIF) and cosmetic product notification dossier prepared by Butter-C, with a microbiological risk assessment for the anhydrous product.
- Packaging
- Label design with a slip warning, printing and packing run in parallel with formula development.
Suggested product concept
MCT – sunflower shower oil for dry skin, light woody scent
A product concept to help you picture the possibilities — not a ready-made product for sale. The actual formula is built around your brand's positioning and price range.
MCT oil and high-oleic sunflower oil
A light, oxidation-stable base; the fatty-acid profile of the sunflower oil is checked on the COA.
Oil-soluble emulsifier system
PEG-20 Glyceryl Triisostearate with Sorbeth-30 Tetraoleate, ratio set by cold clarity, emulsification tests and after-rinse feel.
Tocopherol, light woody scent
Antioxidant for the oil phase; low fragrance level with an IFRA certificate for rinse-off products; a fragrance-free version can run in parallel.
200 ml plastic flip-top bottle
A small amount per use; the label explains use on wet skin, rinsing off, and the slip warning.
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 formula to match.
Named oil
MCT, sunflower, sweet almond, rice bran, jojoba — sets base odor, oxidative stability and price per liter.
Emulsifier system
PEG-based or PEG-free — affects clarity, conversion speed, ingredient list and raw-material sourcing.
After-rinse feel
Clean and dry or with a little oil softness — balanced between emulsifier level and base oil, assessed in users.
Fragrance
Fragrance-free, woody, floral, citrus; cold-pressed citrus oils need a furocoumarin COA.
Packaging
Flip-top or pump; household or large size; textured bottle body against slipping from the hand.
Ingredient direction
PEG-free, mineral-oil-free, vegan, fragrance-free — please specify at the outset.
Further reading
Related knowledge
PEG-7 glyceryl cocoate in cosmetics
A water-soluble emollient common in body washes; why solubility must be tested in the actual oil phase (in Vietnamese).
Polysorbate 80 in cosmetics
Helps oil bases rinse off; the oleate chain, peroxides and 1,4-dioxane (in Vietnamese).
MCT oil (Caprylic/Capric Triglyceride)
A light base oil with few double bonds and a 2022 CIR safety assessment (in Vietnamese).
Double cleansing
The study of eight shower oils and surfactant residues after rinsing (in Vietnamese).
Massage oil OEM/ODM manufacturing
A leave-on oil for spas — different from shower oil in purpose and emulsifier level.
After-bath body oil OEM/ODM manufacturing
An oil applied after leaving the shower area and not rinsed off; the same slip issue.
Body wash OEM/ODM manufacturing
A foaming whole-body cleanser with a water-based surfactant system.
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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