What it is
The register’s chemical name for it: “1,2-Dihydroxypentane.”
- EU register name (INCI)
- PENTYLENE GLYCOL
- CAS number
- 5343-92-0
- EC number
- 226-285-3
What the register lists it for
These are the uses the European Commission’s CosIng register lists for Pentylene 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.
- 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).”
- Skin conditioning
-
The register’s broad role for ingredients that keep skin in good condition. On a hair label it often sits beside a hair role, or marks a plant oil or extract.
Register definition: “Maintaining the skin in good condition.”
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.
- Shampoos 2 labels First five names: 0 of 2 Shampoos without 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 3 labels First five names: 1 of 3 Stylers without it
- Protein treatments 1 label First five names: 0 of 1 Protein treatments without it
- Heat protectants 2 labels First five names: 1 of 2 Heat protectants without it
- Hair oils 1 label First five names: 0 of 1 Hair oils without it
Every label, product by product (12)
- OLAPLEX Nº.4CURL Bond Shaper Hydrating Curl Shampoo Shampoo 24th of 62 names
- Bouclème Curl Cleanser Shampoo 17th of 35 names
- Bouclème Curl Conditioner Rinse-out conditioner 17th of 38 names
- Bouclème Intensive Moisture Treatment Deep conditioner 37th of 50 names
- Bouclème Curl Cream Leave-in conditioner 24th of 38 names
- Bouclème Super Volumising Foam Styler 4th of 36 names
- Cécred Moisture Sealing Lotion Styler 37th of 48 names
- Bouclème Super Hold Styler Styler 42nd of 48 names
- Briogeo Don't Despair, Repair! MegaStrength+ Rice Water Protein + Moisture Strengthening Treatment Protein treatment · listed as Pentylene Glycol* 23rd of 35 names
- Bouclème Curl Defence Spray Heat protectant 2nd of 35 names
- Curlsmith Curlshield Cream Heat protectant 19th of 37 names
- Bouclème Revive 5 Hair Oil Hair oil 13th of 31 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 solvent ingredients on these labels
- Water (Aqua/Eau) 166 labels
- Limonene 75 labels
- Propanediol 27 labels
- Isopropyl Alcohol 15 labels
- 1,2-Hexanediol 3 labels
- C13-14 Isoalkane 2 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.