The EU banned DOP in February 2015. Since then, the global plasticizers market has grown to over $18 billion, and the race to find workable non-phthalate replacements has only intensified. DOTP and DINCH get most of the attention, but a third cyclohexanoate option — DEHCH — solves several problems that those two leave open.
DEHCH stands for bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate. It is a non-phthalate plasticizer made by hydrogenating the aromatic ring of a phthalate precursor, converting it into a cyclohexane ring that cannot bind to hormone receptors. If you are evaluating non-phthalate options for food contact, toys, or other sensitive PVC applications, DEHCH deserves a closer look — but it comes with trade-offs worth understanding before you specify it.
How DEHCH Is Made
DEHCH is produced through catalytic hydrogenation — adding hydrogen to the aromatic (benzene) ring of a phthalate ester precursor, converting it into a non-planar cyclohexane ring. Hanwha Solutions, the primary commercial manufacturer, produces Eco-DEHCH by hydrogenating DOTP (dioctyl terephthalate). The process eliminates the structural feature responsible for endocrine disruption in traditional phthalates. Only a handful of global producers have mastered this hydrogenation technology at commercial scale.
The planar aromatic ring in phthalates like DEHP is what allows them to bind to hormone receptors and disrupt the endocrine system. The cyclohexane ring in DEHCH is three-dimensional and bulky — it simply cannot fit into the same receptor binding sites. This is the same principle behind DINCH, which is the hydrogenated analog of DINP. DEHCH is the analog of DEHP’s terephthalate isomer (DOTP), so these two cyclohexanoates share a chemical logic but differ in their alcohol chain length and resulting properties.
The 1,2-Isomer vs 1,4-Isomer Distinction
This is where suppliers cause confusion — and where procurement mistakes happen.
Two distinct DEHCH isomers exist with different CAS numbers, different properties, and different regulatory status:
- 1,4-DEHCH (CAS 84731-70-4): This is Hanwha’s Eco-DEHCH. It is the isomer that EFSA evaluated, that the EU authorized under Regulation 2023/1627, and that FDA cleared in 2017. Density 0.984 g/cm3, flash point 213.7 C, water solubility 47 ug/L at 20 C.
- 1,2-DEHCH (CAS 84-71-9): A different spatial arrangement of the same molecular formula. Lower density (0.950-0.965 g/cm3), lower flash point (190 C minimum). This isomer does not carry the same regulatory clearances as the 1,4-isomer.
Before adding any DEHCH to your formulation, confirm which CAS number appears on the certificate of analysis. For food-contact or toy applications requiring EU or FDA compliance, specify CAS 84731-70-4 explicitly. I have seen purchase orders reference “DEHCH” generically, only to receive the wrong isomer — a compliance risk that is entirely avoidable.
Safety Profile and Regulatory Approvals
DEHCH has one of the more thorough safety dossiers among newer non-phthalate plasticizers.
The oral reference dose (RfD) is 0.3 mg/kg-day, derived from an OECD 422 combined study in rats using a total uncertainty factor of 100. That 100-fold factor breaks down as: 3x for interspecies conversion, 10x for human variability, and 3x for database gaps — with subchronic-to-chronic and LOAEL-to-NOAEL factors at 1x each, reflecting the clean toxicology profile. The study found minimal effects on liver, spleen, and thyroid, with no indication of developmental or reproductive toxicity. Genotoxicity testing confirmed no mutagenic or clastogenic potential.
Where toxicological data were incomplete, researchers used read-across from structurally similar DOTP and DINCH — both of which have more extensive study databases. This analog-based validation is standard regulatory methodology, and the fact that DEHCH’s closest chemical relatives are already cleared strengthens its safety case.
The regulatory timeline is specific and worth tracking:
- 2017: US FDA approved Eco-DEHCH for plastic wraps, bottle caps, and food-related products.
- December 2019: EFSA published a favorable scientific opinion, concluding DEHCH “does not raise a concern for genotoxicity.” Migration testing showed 0.034 mg/kg from PVC films at maximum 25% loading — well below the 0.05 mg/kg limit EFSA established.
- August 2023: EU Regulation 2023/1627 formally added DEHCH (FCM substance No. 1079) to the authorized substances list for plastic food-contact materials, effective August 31, 2023.
That migration result deserves attention: 0.034 mg/kg observed versus 0.05 mg/kg permitted gives a comfortable 32% safety margin even at maximum loading. The formulation ratio I recommend is staying at or below 20% w/w for food-contact films to maintain that margin with room for process variation.
DEHCH Compared to DINCH and DOTP
All three are non-phthalate plasticizers, but they differ in meaningful ways that affect formulation decisions.
DINCH (CAS 166412-78-8) is the hydrogenated analog of DINP, using isononyl alcohol chains. It has the longest commercial track record among cyclohexanoates, the broadest regulatory clearance portfolio, and established use in medical PVC — particularly blood-contact applications where its hemolysis rating is superior. DINCH is the default choice when you need the widest regulatory acceptance or medical-grade documentation.
DOTP (CAS 6422-86-2) is a terephthalate, not a cyclohexanoate — it retains an aromatic ring, just repositioned from ortho to para orientation. It is the most cost-effective non-phthalate option and the most widely available. However, DOTP has known compatibility limitations with PVC. ExxonMobil originally declined to commercialize DOTP specifically because of poor PVC compatibility. Formulators working with DOTP often need longer mixing cycles and higher temperatures to achieve full absorption.
DEHCH occupies a middle position. Industry sources report plasticizing speed roughly twice that of both DOTP and DINCH — though this claim comes from manufacturers, not independent studies, so treat it as directional. Its migration resistance is strong (the 0.034 mg/kg EFSA result), and its volatility is low. Where DEHCH falls short: limited supplier base (Hanwha Solutions is the primary producer), higher cost than DOTP, a smaller production footprint than DINCH, and no established track record in medical PVC applications where DINCH and TOTM dominate.
| Factor | DEHCH (1,4-isomer) | DINCH | DOTP |
|---|---|---|---|
| Chemical class | Cyclohexanoate | Cyclohexanoate | Terephthalate |
| CAS number | 84731-70-4 | 166412-78-8 | 6422-86-2 |
| Phthalate analog | DEHP/DOTP | DINP | — (is itself a terephthalate) |
| EU food contact | Yes (2023) | Yes | Yes |
| FDA cleared | Yes (2017) | Yes | Yes |
| Medical PVC use | Not established | Yes (blood contact) | Limited |
| Relative cost | Higher | Higher | Lower |
| Supplier base | Narrow | Broad | Broad |
No single plasticizer spec sheet tells you which one to use. If you are switching from DOP to a non-phthalate alternative, the right choice depends on your application’s regulatory requirements, processing constraints, and supply chain realities — not on which product has the best marketing claims.
Where DEHCH Fits
DEHCH is a well-validated non-phthalate plasticizer with strong safety data, specific regulatory clearances, and a chemical structure that eliminates endocrine disruption by design. It is not a universal replacement for DOP, DINCH, or DOTP.
For food-contact PVC films, children’s toys, and sensitive consumer goods requiring EU and FDA clearance with low migration, DEHCH is a strong candidate — confirm the 1,4-isomer (CAS 84731-70-4) on every shipment. For medical PVC or the broadest global regulatory portfolio, specify DINCH. For cost-sensitive general-purpose formulations, DOTP still makes economic sense despite its compatibility drawbacks.
Before specifying any of them, run your own absorption and migration tests at your actual processing conditions — published data gives you a starting point, not a finished formulation.