1,3-Propanediol is a multifunctional liquid cosmetic ingredient used in skincare, haircare, personal-care and other cosmetic formulations. It is also known as Trimethylene Glycol and Propane-1,3-diol and is identified by CAS Number 504-63-2.
1,3-Propanediol has the molecular formula C₃H₈O₂ and a molecular weight of approximately 76.09 g/mol. It is a clear, colourless, water-miscible liquid that can function as a humectant, solvent and skin-conditioning ingredient in cosmetic formulations.
In cosmetic applications, 1,3-Propanediol is particularly useful where formulators require a multifunctional ingredient that can support moisture retention, ingredient solubilization, formulation texture and sensory properties.
1,3-Propanediol should not be confused with 1,2-Propanediol, which is the chemical name for Propylene Glycol. Although both compounds have the same molecular formula, their hydroxyl groups are positioned differently, making them different chemical substances with different physical and formulation properties.
1,3-Propanediol is a three-carbon diol containing two hydroxyl groups positioned at the terminal carbon atoms of the molecule. Its systematic chemical name is propane-1,3-diol.
It is generally supplied as a clear, colourless liquid with good water compatibility. Its chemical structure gives it useful humectant and solvent characteristics for cosmetic formulation development.
1,3-Propanediol can help attract and retain moisture in formulations while also supporting the dissolution or dispersion of selected ingredients. It may contribute to the sensory profile and overall texture of finished cosmetic products.
Depending on the manufacturing route and grade, 1,3-Propanediol may be produced through conventional chemical processes or through bio-based fermentation routes. The applicable origin should be verified from the supplier's technical documentation.
1,3-Propanediol can function as a humectant in cosmetic formulations.
Humectants help attract and retain moisture, supporting the moisture characteristics of creams, lotions, gels, serums and other personal-care formulations.
It can therefore be considered for:
The actual concentration should be determined according to the complete formulation and desired sensory and functional properties.
1,3-Propanediol can also function as a solvent for suitable cosmetic ingredients.
Its water compatibility makes it useful in aqueous formulations where selected ingredients require assistance with dissolution or incorporation.
It can be evaluated for use with:
Its effectiveness as a solvent depends on the chemical characteristics of the ingredient being incorporated.
1,3-Propanediol can contribute to the conditioning characteristics of cosmetic formulations.
When incorporated into skincare products, it may support a smooth formulation feel and help maintain desirable moisture characteristics.
It can therefore be considered in:
1,3-Propanediol can influence the sensory profile of cosmetic formulations.
Depending on the formulation system and concentration, it can contribute to spreadability, slip and overall product feel.
This can be particularly useful in formulations where a multifunctional liquid ingredient is required without introducing a heavy oily character.
1,3-Propanediol can be used in:
Its suitability depends on the formulation composition, concentration, product type and applicable cosmetic requirements.
1,3-Propanediol is normally supplied as a clear, colourless liquid. Its liquid physical state allows convenient incorporation into aqueous and mixed-phase cosmetic formulations.
1,3-Propanediol is highly compatible with water and can be incorporated into many water-based cosmetic systems.
This property makes it useful in formulations such as serums, toners, lotions and gels.
As a diol with two hydroxyl groups, 1,3-Propanediol can interact with water and contribute to moisture-retention properties.
The required concentration should be established through formulation testing because humectant performance depends on the complete formulation.
High-purity cosmetic grades are available. The exact assay requirement depends on the intended grade and supplier specification.
For commercial manufacturing, the current COA/TDS should be used as the controlling specification rather than applying a generic numerical value to every grade.
Density is grade- and temperature-dependent. A representative high-purity 1,3-Propanediol specification may report density close to 1.05 g/mL at 20°C.
The exact value should be confirmed from the applicable supplier specification.
Refractive index is dependent on purity and measurement temperature. The value should therefore be taken from the applicable COA/TDS when used as a release specification.
Because 1,3-Propanediol is water-compatible and hygroscopic, water content can be an important quality parameter.
The applicable grade specification should be followed for the maximum permitted water content.
Neat 1,3-Propanediol does not have a single universal formulation pH in the same manner as an aqueous cosmetic solution.
The pH of the finished product should be measured after complete formulation.
Compatibility should be evaluated with:
Compatibility testing should be performed using the complete finished formulation.
1,3-Propanediol can generally be added during the aqueous or water-soluble phase of a formulation.
The order of addition, mixing temperature, concentration and interaction with polymers or other ingredients should be determined during formulation development.
1,3-Propanediol should be stored in tightly closed containers under suitable conditions and protected from contamination, excessive heat and unnecessary environmental exposure.
Supplier-specific storage instructions should always be followed.
1,3-Propanediol can be used in:
Its multifunctional characteristics make it suitable for cosmetic formulators looking for a water-compatible humectant and solvent.
For cosmetic manufacturers, 1,3-Propanediol provides a multifunctional liquid ingredient that can support humectancy, solubilization and formulation texture.
It can be incorporated into a broad range of skincare, haircare and personal-care formulations.
When selecting a commercial grade, manufacturers should evaluate:
The applicable supplier COA and TDS should control the specification for the actual material supplied.
Swapnroop provides 1,3-Propanediol for applicable cosmetic, personal-care and formulation requirements with a focus on consistent quality and commercial supply.
Key advantages include:
1,3-Propanediol is a three-carbon diol used as a multifunctional cosmetic ingredient, particularly for humectant, solvent and formulation-support applications.
The CAS Number of 1,3-Propanediol is 504-63-2.
The cosmetic INCI name is generally Propanediol.
The molecular formula is C₃H₈O₂.
The molecular weight of 1,3-Propanediol is approximately 76.09 g/mol.
Yes. 1,3-Propanediol is normally supplied as a clear, colourless liquid.
1,3-Propanediol is used primarily as a multifunctional ingredient for humectant, solvent and formulation-support applications.
Yes. 1,3-Propanediol can function as a humectant and help support moisture retention in suitable cosmetic formulations.
Yes. Its water compatibility and chemical properties allow it to function as a solvent for suitable cosmetic ingredients.
Yes. 1,3-Propanediol is highly compatible with water and can be used in many aqueous cosmetic formulations.
No. 1,3-Propanediol and Propylene Glycol are different chemical substances. Propylene Glycol is 1,2-Propanediol, while this product is 1,3-Propanediol. Both have the molecular formula C₃H₈O₂ but different molecular structures.
1,2-Propanediol is commonly called Propylene Glycol, while 1,3-Propanediol is commonly called Trimethylene Glycol. The positions of the hydroxyl groups differ between the two molecules.
Yes. It can be considered for skincare formulations such as moisturizers, serums, creams, lotions and gels where humectant and solvent functionality is required.
Yes. It can be evaluated for use in haircare, conditioning, scalp-care and other personal-care formulations.
It should be stored in tightly closed containers under suitable conditions and protected from contamination and excessive environmental exposure. The supplier's current storage recommendations should be followed.
| Parameter | Specification |
|---|---|
| Appearance | Colourless to light-yellow liquid or oily liquid |