At equivalent Shore A in a flexible PVC compound, DINCH needs roughly 40 phr where DINP needs roughly 30 phr. Once that 33% higher loading is multiplied by DINCH’s per-unit price premium, the finished compound runs about 15% more.
That single number is what a switch decision turns on, not the per-ton plasticizer price tag procurement teams usually start with. The compatibility between plasticizer and polymer drives the loading, the loading drives the cost, and the cost is only justified by what the regulatory exposure window does for the application.
DINCH Is DINP With the Aromatic Ring Hydrogenated
DINCH (1,2-cyclohexane dicarboxylic acid diisononyl ester) is structurally DINP (di-isononyl phthalate) with the aromatic benzene ring hydrogenated to a saturated cyclohexane ring. Same C9 isononyl alcohol tails, same diester backbone, no ortho-phthalate arrangement.
BASF developed DINCH in 2002 specifically as the closest non-phthalate analog for close-human-contact applications. The ortho-phthalate ester arrangement is the structural feature ECHA and EFSA flag for endocrine activity, and the hydrogenation step is the entire safety case.
Everything else — phr efficiency, volatility, gelation temperature — moves only slightly from the DINP baseline, which is why procurement teams keep treating DINCH as a near-drop-in.
The molecular structure explains why the loading delta is real but small. Cyclohexane is less polar than benzene, so solvation of the PVC chain is marginally weaker. That gap shows up as needing more material to hit the same Shore A.
The phr-Normalized Cost Delta: Roughly 15% at Equivalent Shore A
DINCH at roughly 40 phr matches the flexibility DINP delivers at roughly 30 phr in standard flexible PVC. Bastone compounding data lines up with the public figures: DINCH at 40-50 phr lands Shore A 75-85, the target range for children’s products and most cushion-flooring applications.
| Shore A target | DINP loading | DINCH loading |
|---|---|---|
| 75 (toy / general flex) | ~30 phr | ~40 phr |
| 85 (cushion flooring) | ~40 phr | ~50 phr |
| Per-unit price gap | baseline | ~10% above DINP |
| Finished-compound cost | baseline | ~15% above DINP |
DINP’s own efficiency is already a slight step off the legacy DEHP baseline — about 104 phr DINP to match 100 phr DEHP — and DINCH adds another notch. The 33% loading multiplier is what turns DINCH’s per-unit premium into a ~15% finished-compound premium.
The cost picture sometimes gets reported as smaller. Larry Wallace at Spectrum Plastics has written that the per-unit plasticizer price gap “often ranges below 10%” — and that number is correct.
Wallace’s 10% per-unit gap doesn’t contradict the 15% finished-compound figure because the two figures measure different things: per-ton plasticizer-to-plasticizer versus per-finished-Shore-A-target. The phr loading adjustment is the multiplier procurement spreadsheets keep missing.
As of 2025, US DINP prices sit at the low end of the $1,700-$2,000/MT band for major plasticizers. ResourceWise notes DINP has seen price erosion as tariffs on Asian suppliers and Evonik Oxeno reshape supply — DINP isn’t going away on economics.
What makes the cost argument bite is whether DINCH supply can match a global compounder’s volumes. BASF doubled Hexamoll DINCH capacity at Ludwigshafen from 100,000 to 200,000 metric tons per year, and Evonik Oxeno has separately expanded INA-based DINCH.
The older single-supplier-risk objection no longer holds in 2025-2026. The procurement decision compresses to: pay roughly 15% more on finished compound, and what does that buy you on the regulatory side?
The Regulatory Asymmetry: US Cleared DINP in 2025, EU Still Amending
The DINP regulatory clock is asymmetric by export market, which is the procurement signal most “phthalates are phasing out” framings get wrong.
- US, Jan 2025 — EPA completed TSCA risk evaluations and cleared DINP for all 15 consumer uses. Not in retreat domestically.
- EU, Aug 2025 — Commission Regulation (EU) 2025/1731 revised CMR entries 28-30 of REACH Annex XVII, effective September 1, 2025.
- EU, Jan 2026 — European Commission released a draft proposal further updating Annex XVII.
Per REACH regulations, DINP itself is not on Annex XIV, but the CMR framework is tightening and the procurement risk window for EU-export flexible PVC remains open.
DINCH’s regulatory case sits on the other side of this asymmetry, and its cross-sector adoption story against DEHP is what most procurement teams know it for. BASF has invested more than €7 million in toxicological research on Hexamoll DINCH.
The material carries clearances for toys, medical devices, food contact, sport and leisure goods, flooring, and wallcovering across multiple jurisdictions — which is the practical content of “non-phthalate” for procurement, not a category label.
The honest framing matters here: DINCH is not endocrine-inert in vitro. A 2021 NIH-hosted study by Moche et al. (PMC7886589, 48 citations) measured steroidogenesis in H295R adrenal cells. DINP induced a 4.7-fold estradiol increase at 30 μM; DINCH a 4-fold estradiol increase at 3 μM; DEHP a 2-fold increase.
The DINCH safety case rests on exposure-level real-world data and low migration rates, not on zero in vitro activity. Any procurement story that frames DINCH as “the safer choice” without that caveat is marketing, not engineering.
Where Each One Wins: Four Flexible PVC Application Buckets
The verdict splits cleanly across four flexible PVC application buckets. The 15% premium only earns itself back where regulatory exposure or migration limits are doing real work.
| Application bucket | Verdict | Why |
|---|---|---|
| Toys, food contact, EU-export children’s goods | Switch to DINCH | Regulatory finality + migration limits dominate cost |
| Medical / blood-contact tubing | Switch to DINCH | CFDA, FDA, EFSA clearances + low migration |
| Industrial wire & cable, footwear | Keep DINP | TSCA-cleared, phr efficiency advantage, low human contact |
| Outside-EU flooring | Keep DINP, monitor | Cost dominates until regulatory pressure arrives |
Real evidence sits behind both sides of that table. BASF disclosed that flooring producer Vinyl Tech adopted Hexamoll DINCH starting in 2012, a cost-default flooring application where the regulatory and indoor-air-quality argument won against DINP economics.
China’s CFDA approved DINCH for extracorporeal tubing used in artificial heart and lung machines — the highest-bar blood-contact application a plasticizer can clear. On the DINP-keeps-winning side, SpecialChem notes roughly 95% of DINP currently sits in construction, industrial, and durable-goods applications. Wire and cable, film and sheet, flooring, industrial hoses, footwear — a footprint TSCA’s January 2025 clearance leaves intact.
The Bottom Line
For toy, food-contact, medical, and EU-export flexible PVC lines, the roughly 15% finished-compound premium for DINCH at equivalent Shore A is the right call. Regulatory headroom and migration data justify it, and BASF’s doubled Ludwigshafen capacity plus Evonik Oxeno’s INA-DINCH expansion close the older supply-risk objection.
For industrial cable, footwear, and outside-EU flooring, DINP keeps winning on phr efficiency and US TSCA clearance through 2025. The switch math doesn’t pay off until a regulatory trigger arrives.
The real procurement number is finished-compound-cost-at-equivalent-Shore-A, not per-ton plasticizer-to-plasticizer. The application bucket decides whether that number is worth paying.