What it is
The register’s chemical name for it: “1,1'-Oxydipropan-2-ol; Oxydipropan-2-ol; Hydroxypropyloxypropanol.”
- EU register name (INCI)
- DIPROPYLENE GLYCOL
- CAS number
- 110-98-5 / 25265-71-8
- EC number
- 203-821-4 / 246-770-3
- Other names in the register
- 1,1'-Oxydipropan-2-ol; Oxydipropan-2-ol; Hydroxypropyloxypropanol
What the register lists it for
These are the uses the European Commission’s CosIng register lists for Dipropylene Glycol in any cosmetic, hair roles first. They say why a maker might add it, not what it does in one formula, and they aren’t a safety rating.
- Fragrance
-
Gives the product its smell or covers an unpleasant one. A label may name each scent ingredient or group them as Fragrance (Parfum).
Register definition: “Imparting an odour or taste. Creating a perceivable pleasant smell and/or masking a bad smell.”
- Solvent
-
Dissolves other ingredients. Water is the most common; some alcohols and glycols carry this role too.
Register definition: “Dissolving other components of cosmetics. Solvents are usually liquids (aqueous and nonaqueous).”
- Viscosity controlling
-
Makes a product thicker or thinner, so a gel holds its shape or a shampoo pours. Gums, cellulose and some salts carry this role.
Register definition: “Increasing or decreasing the viscosity (thickness) of cosmetics.”
- Perfuming
-
Used as a perfume or scent material. Essential oils and their scent compounds, such as linalool and limonene, carry this role.
Register definition: “Used for perfume and aromatic raw materials.”
Where it sits on each label
US labels list ingredients from most to least, except that those at 1% or less may follow in any order. A name near the top is a large part of the formula. A label doesn’t mark where the 1% point falls, so further down, the order says little about how much is in it.
- Rinse-out conditioners 1 label First five names: 0 of 1 Rinse-out conditioners without it
- Deep conditioners 1 label First five names: 0 of 1 Deep conditioners without it
- Leave-in conditioners 1 label First five names: 0 of 1 Leave-in conditioners without it
- Stylers 2 labels First five names: 0 of 2 Stylers without it
Every label, product by product (5)
- Cécred Hydrating Conditioner Rinse-out conditioner 8th of 50 names
- Cécred Moisturizing Deep Conditioner Deep conditioner 34th of 41 names
- Innersense Organic Beauty Sweet Spirit Leave In Conditioner Leave-in conditioner 7th of 24 names
- TRESemmé Bouncy Curls Defining Cream Styler 11th of 25 names
- Ouidad Curl Quencher Moisturizing Styling Gel Styler 22nd of 38 names
Each line runs from the first name on a label to the last; a dot is where this ingredient sits. Makers change formulas now and then; if the list on your bottle differs, go by your bottle.
Your next step
Other fragrance ingredients on these labels
- Fragrance (Parfum) 133 labels
- Potassium Sorbate 61 labels
- Sodium Benzoate 61 labels
- Ricinus Communis (Castor) Seed Oil 32 labels
- Caprylic/Capric Triglyceride 26 labels
- Olea Europaea (Olive) Fruit Oil 26 labels
- Sodium Chloride 26 labels
- Benzoic Acid 25 labels
Updated · The name, numbers and uses come from the European Commission’s CosIng entry (CC BY 4.0); we write the uses in US spelling and put the hair ones first. The labels are each maker’s own. The order rule is the FDA’s Cosmetics Labeling Guide. All our sources are on the Sources page.