Table of Contents

• 1. A Material That Holds Your Food Safe — and a Market Almost Nobody Knows About

• 2. How EVOH Actually Works: The Molecular Story

• 3. Kuraray's 50-Year Head Start: How the Monopoly Was Built

• 4. The Global Supply Chain: Four Producers for the Whole World

• 5. EVOH in Retort Pouches: Structures and Applications

• 6. China's EVOH Dependency — and the Race to Produce Domestically

• 7. The Supply Risk Nobody Talks About

• 8. The New Growth Driver: Recyclability

• 9. Market Size and Outlook

• 10. What This Means for Packaging Buyers

• 11. Frequently Asked Questions

1. A Material That Holds Your Food Safe — and a Market Almost Nobody Knows About

Open any wet pet food pouch with a clear window, any transparent ready-to-eat meal, or any microwaveable retort pouch, and you are almost certainly holding a product whose shelf life depends on a thin layer of EVOH — ethylene vinyl alcohol copolymer. The layer is typically 5–15 micrometers thick, invisible to the eye, sandwiched between layers of polyethylene or polypropylene. Without it, oxygen would permeate the package and spoil the contents within days.

EVOH is not a household name. Even in the packaging industry, it is known primarily to laminate engineers and film formulators. But it sits at the center of one of the most concentrated supply chains in global manufacturing: a material present in billions of food packages annually, with fewer commercial producers than the global market for commercial aircraft engines.

Understanding who makes EVOH, how, and why that structure exists — matters to every packaging buyer specifying high-barrier flexible structures.

2. How EVOH Actually Works: The Molecular Story

EVOH is a copolymer of ethylene and vinyl alcohol, produced by hydrolysis of ethylene vinyl acetate (EVA). Its oxygen barrier performance comes from its molecular structure: the hydroxyl groups (-OH) on the vinyl alcohol units form a tightly-packed crystalline lattice that is highly impermeable to gas molecules.

At low humidity, EVOH achieves OTR values of 0.03–0.5 cc/m²·day depending on ethylene content and grade — among the lowest of any polymer. For context, standard polyamide (nylon) achieves 20–40 cc/m²·day; aluminum foil achieves <0.01 cc/m²·day (effectively complete barrier). EVOH sits between these extremes but much closer to aluminum.

The critical technical trade-off is humidity sensitivity. The same hydroxyl groups that block oxygen also attract water molecules. At high relative humidity (80–85% RH), water disrupts the crystal lattice, swelling the polymer and creating gas diffusion pathways. EVOH's OTR can increase 20–30× under these conditions. This is why EVOH must always be sandwiched between moisture-barrier layers in any laminate — typically polyethylene on both sides.

The ethylene content of EVOH (typically 27–48 mol%) creates a direct trade-off: lower ethylene content = better oxygen barrier but more humidity sensitivity and lower processability; higher ethylene content = easier processing but weaker barrier. Packaging engineers select grades by matching the product's oxygen sensitivity to the processing and use conditions.

Table 1: EVOH vs Competing Barrier Materials — Key Properties for Retort Applications

Sources: Kuraray EVAL technical data; published OTR values at 23°C. RH conditions noted. *All-PE structure requires EVOH ≤5 wt% for CEFLEX recyclability compliance.

3. Kuraray's 50-Year Head Start: How the Monopoly Was Built

Kuraray Co., Ltd. was founded in 1926 in Japan as a textiles company, and expanded into synthetic fibers and specialty chemicals through the mid-20th century. Its path to EVOH began through polyvinyl alcohol (PVA) chemistry — the same raw material chemistry from which EVOH is derived.

In 1972, Kuraray became the first company in the world to achieve industrial-scale production of EVOH, commercializing it under the EVAL™ trademark. The technical challenge was substantial: EVOH requires extremely precise control of the ethylene/vinyl acetate copolymerization and saponification (hydrolysis) process to achieve consistent molecular weight distribution and ethylene mole fraction across production runs. Deviations of even a few percentage points in ethylene content produce measurably different barrier performance — quality control that demands deep process expertise.

For twelve years after Kuraray's commercialization, no other company successfully produced EVOH at industrial scale. Nippon Synthetic Chemical Industry (now Mitsubishi Chemical) launched its Soarnol™ brand in 1984 — twelve years later. Chang Chun Petrochemical in Taiwan followed in 2007. Sinopec's 川维化工 achieved pilot-scale production in 2019 and industrial-scale in 2024 — 52 years after Kuraray.

4. The Global Supply Chain: Four Producers for the Whole World

As of 2025, the global EVOH market is served by four commercial producers. This is an extraordinarily concentrated supply base for a material that is a direct input to billions of units of food packaging annually.

Table 2: Global EVOH Producers — Capacity, Market Position, and Expansion Plans

Sources: Kuraray corporate announcements; Credence Research (2024); Chinese industry reports (中国化信, 新浪财经); company announcements. Capacity figures approximate and subject to expansion timelines.

Kuraray's existing 103,000 t/y capacity is distributed across three geographies: the US (approximately 58,000 t/y, the largest single base), Belgium (approximately 35,000 t/y), and Japan (approximately 10,000 t/y). The planned Singapore plant (18,000 t/y Phase 1, end 2026) will be the first Asian production facility outside Japan — a strategic response to the Asia-Pacific region's growing share of global EVOH demand.

The 2023 announcement to expand US and European capacity by a combined 10,000 t/y (phased 2024 and 2026) means Kuraray's total capacity is moving from 103,000 toward approximately 131,000 t/y by 2026–2027, once Singapore is included. This represents a 27% capacity increase within four years — an unusually aggressive investment cycle for specialty polymer production.

Table 3: EVOH Production Capacity Expansion Announcements (2023–2026)

Sources: Kuraray corporate press releases (Aug 2023, Mar 2024, Aug 2024); Chinese industry media reports; Mitsubishi Chemical announcements. All capacity figures subject to final commissioning dates.

5. EVOH in Retort Pouches: Structures and Applications

EVOH appears in retort pouches in two distinct roles: as the primary barrier layer in transparent (aluminum-free) retort structures, and as the barrier component in all-PE mono-material structures designed for recyclability. Understanding which role applies to your application determines which EVOH grade to specify.

Table 4: Common Retort Pouch Laminate Structures Containing EVOH

Source: Kuraray EVAL technical literature; Sunkey Packaging structure specifications. All structures require overpressure retort processing to prevent pouch deformation. EVOH layer thickness typically 5–15 µm in coextruded structures.

The most common application for EVOH in retort pouches is the transparent structure: PET / Adhesive / EVOH / Adhesive / CPP. This structure allows the consumer to see the product directly, enables microwave heating, and provides an OTR suitable for shelf lives of 12–18 months for most food products. Premium variants add a nylon (BOPA) layer for puncture resistance.

For maximum shelf life (18–36 months), especially for low-acid content (pH > 4.6), aluminum foil structures remain the dominant specification — not because of cost, but because aluminum's near-zero OTR provides a wider safety margin against spoilage. EVOH structures at the same gauge provide sufficient barrier for most applications but require more careful product and shelf-life validation.

6. China's EVOH Dependency — and the Race to Produce Domestically

China consumes approximately 30,000–40,000 tonnes of EVOH annually and has historically imported nearly all of it. The dependency is not just a cost issue — it represents a strategic vulnerability in China's food packaging supply chain. EVOH is classified as a national encouraged industry under China's NDRC Catalogue (2024 Edition), signaling government support for domestic production.

Table 5: China's EVOH Supply Situation (2025)

Sources: 中国化信 (chemnews.com.cn, Aug 2024); 新浪财经 (EVOH industry report, Nov 2024); 中化信咨询 (July 2025); company announcements. Note: market data from multiple Chinese industry sources; figures represent consensus estimates.

The 川维化工 (Sinopec Sichuan Vinylon Works) story illustrates both the difficulty and the strategic importance of domestic EVOH production. Sinopec began preliminary EVOH research in 2011, completed a 500 t/y pilot plant in 2018, and only reached industrial-scale commissioning in June 2024 — 13 years of development. The company is now China's first mainland industrial-scale EVOH producer, described internally as 'the fourth company globally to master EVOH production technology.'

The gap between pilot and industrial scale reflects the technical barriers that have protected Kuraray's position for 50 years: precise molecular weight control, consistent ethylene mole fraction, and the process knowledge to maintain grade specifications across production runs. 川维化工's Phase 1 product entered the packaging market in H2 2024, initially focusing on multilayer bottles — a lower specification application than high-barrier retort film, where Kuraray's quality consistency advantage remains significant.

7. The Supply Risk Nobody Talks About

The concentration of EVOH production in four companies — with one company holding 60% of global capacity across three geographies — creates a supply risk that most packaging engineers do not explicitly quantify when specifying EVOH structures.

In 2022, this risk materialized indirectly. Three major US acetic acid producers (Celanese, Ineos, LyondellBasell) experienced simultaneous force majeure events. VAM (vinyl acetate monomer), the key raw material for EVOH, is derived from acetic acid — and US plants produce a disproportionate share of global VAM supply. The result: EVOH prices in Asia-Pacific increased by $3.30/kg over two years (Kuraray's reported pricing); Chinese market prices for standard EVOH grades reached over ¥100/kg at peak. Spot supply became constrained.

For retort pouch converters and food manufacturers with aluminum foil specifications, this supply event was irrelevant — aluminum foil has a different, independent supply chain. For those who had transitioned to EVOH-based transparent structures, the event was a material cost and supply planning challenge.

This does not argue against specifying EVOH — its performance and recyclability advantages are real. It argues for maintaining dual-qualification of both EVOH and aluminum foil structures where shelf life requirements can be met by both options, and for contracting EVOH supply with minimum 6–12 month forward coverage when building new production lines.

8. The New Growth Driver: Recyclability

For 40 years, EVOH competed with aluminum foil primarily on the basis of transparency and microwaveability. A new competitive driver has emerged since 2022: recyclability.

Aluminum foil laminate structures (PET/Al/CPP, the dominant retort format) are not recyclable in conventional plastics recycling streams — the mixed material construction creates a contamination challenge for both the aluminum and plastic recycling industries. Under the EU Packaging and Packaging Waste Regulation (PPWR), which applies recyclability requirements phasing in from 2030, multilayer aluminum foil structures face increasing pressure.

EVOH-based structures offer a recyclability pathway that aluminum structures do not. CEFLEX (the European flexible packaging recycling consortium) considers polyolefin-dominant structures containing EVOH at ≤5 wt% to be compatible with PE recycling streams. A PE/EVOH/PE structure — an all-mono-material design — can qualify as recyclable in a growing number of European recovery programs. This is driving material science investment across the packaging industry and creating demand for new EVOH grades optimized for mono-material construction.

This recyclability advantage is a primary reason Kuraray is investing aggressively in capacity expansion — the company anticipates 5–6% annual demand growth driven not just by food market expansion but by material substitution: EVOH replacing aluminum foil in applications where the recyclability premium justifies the specification change.

9. Market Size and Outlook

Table 6: Global EVOH Market — Size and Forecast

Sources: Credence Research (2024); Future Market Insights (2024); multiple research providers. Market definition covers EVOH resin including food packaging, automotive, and industrial applications. Figures represent consensus ranges.

The EVOH market — approximately $1 billion in 2024 — is modest in absolute terms relative to commodity plastics, but significant in strategic terms. The high concentration of supply in 4 producers (effectively 2 dominant players) means that price and availability are determined by a small number of capacity decisions. The 2023–2026 expansion cycle (Kuraray +27% global capacity, Mitsubishi Chemical +116% at its UK plant) is designed to bring the market back toward supply surplus after the 2022 tightness.

Asia-Pacific drives volume growth at approximately 6–7% CAGR — faster than the global market average — as food manufacturers in China, India, and Southeast Asia shift toward higher-barrier packaging to meet food safety standards and consumer quality expectations.

10. What This Means for Packaging Buyers

Several practical conclusions for food manufacturers and packaging engineers specifying barrier materials for retort pouches:

• Structure selection: When you specify an EVOH-based transparent retort structure, you are sourcing from a 4-supplier global market with one dominant producer. This is not a reason to avoid EVOH — its performance is well-proven — but it is a reason to include EVOH supply risk in your packaging procurement planning.

• Grade qualification: EVOH grades are not interchangeable across producers. Kuraray EVAL F101B and Nippon Gohsei Soarnol A4412B are both EVOH resins with similar ethylene content, but process compatibility, laminate adhesion performance, and retort processing behavior can differ. When qualifying a new EVOH laminate structure, specify by OTR requirement and ethylene content range — not by a single producer's grade — to give your laminate converter flexibility without compromising the specification.

• Cost trajectory: EVOH prices are subject to raw material volatility (VAM/acetic acid chain). The 2022 spike to >¥100/kg in China should be understood as a structural risk, not an anomaly. When evaluating the total cost of an EVOH-based structure versus aluminum foil, include a raw material volatility premium in the EVOH cost basis.

• Recyclability positioning: If your product or brand has sustainability commitments related to EU PPWR or equivalent regulations, the shift from aluminum foil to EVOH-based structures is a live specification option to evaluate now — not after the regulation requires it.

• China sourcing: As 川维化工 scales and qualifies into food packaging applications, a domestic Chinese EVOH supply source will become viable for standard applications within the next 2–3 years. Monitor grade qualification progress if your sourcing is China-based.

11. Frequently Asked Questions

Q1: What is EVOH and why does it matter for retort packaging?

EVOH (ethylene vinyl alcohol copolymer) is a barrier resin that, when sandwiched between polyolefin layers in a laminate structure, provides oxygen transmission rates (OTR) of 0.03–0.5 cc/m²·day — significantly lower than nylon or standard polyester. In retort packaging, EVOH is the preferred barrier for transparent pouches because aluminum foil, while providing a complete barrier, prevents microwave heating and product visibility. When EVOH is used in a PET/EVOH/CPP or BOPA/EVOH/CPP structure, the pouch can be both retortable at 121°C and transparent.

Q2: Who makes EVOH resin globally?

As of 2025, the global EVOH market has only four commercial-scale producers: Kuraray (Japan, EVAL™ brand, ~60% global market share), Mitsubishi Chemical/Nippon Gohsei (Japan, Soarnol™ brand, ~25–30%), Chang Chun Petrochemical (Taiwan, ~5–8%), and Sinopec's Sichuan Vinylon Works/川维化工 (China mainland, 12,000 t/y since June 2024, <5% and growing). This extreme concentration — four suppliers for a material used in billions of food packages annually — is unusual even among specialty polymers.

Q3: Why is EVOH performance so humidity-sensitive?

EVOH's exceptional gas barrier properties come from tightly-packed crystalline regions in its polymer chain that block gas diffusion. However, water molecules compete for the same hydrogen-bonding sites that create this tight packing — effectively swelling and loosening the crystal lattice. Above 80–85% relative humidity, EVOH's oxygen barrier performance can degrade 20–30× compared to its performance at 0% RH. This is why EVOH must always be sandwiched between moisture-barrier layers (typically PE or PP) in a multilayer structure: the outer layers keep the EVOH dry, allowing it to maintain its barrier performance throughout the product's shelf life.

Q4: What EVOH grade should I specify for retort pouches?

For retort pouches processed at 121°C, Kuraray recommends grades with 29–32 mol% ethylene content (e.g., EVAL F101B or equivalent) — lower ethylene content delivers better oxygen barrier but requires careful processing conditions. For structures requiring improved processability or flexibility, 38–44 mol% grades are used. The sandwich construction (PE or PP on both sides of the EVOH layer) is mandatory for all retort applications — exposure of EVOH to moisture during retort would degrade barrier performance post-processing.

Q5: What is the difference between transparent retort and aluminum foil retort pouches?

The choice comes down to three trade-offs: (1) Barrier completeness — aluminum foil provides near-zero OTR and is impermeable to light; EVOH provides very low but non-zero OTR and is transparent to light. (2) Product interaction — aluminum foil pouches cannot be microwaved; EVOH-containing transparent pouches can. (3) Cost — aluminum foil laminates are typically less expensive per unit of barrier performance at equivalent gauge. For shelf-stable products requiring maximum barrier over 18–24 months (especially low-acid items), aluminum foil structures are the lower-risk specification. For products where consumer visibility or microwaveability is a purchase driver, EVOH-based transparent structures are the correct specification.

Q6: What does Kuraray's Singapore expansion mean for the supply chain?

Kuraray is investing approximately $410 million in a new 18,000 t/y EVOH plant on Jurong Island, Singapore, with operations expected by end 2026. The front-end process is designed for future expansion to 36,000 t/y. For Asian food manufacturers, this represents the first EVOH production capability in Southeast Asia — potentially shortening supply lead times and reducing import dependency compared to sourcing from the US or Belgium. The expansion also signals Kuraray's confidence in 5–6% annual demand growth, driven by the recyclability trend (EVOH is compatible with polyolefin recycling streams, unlike aluminum foil).

Q7: Is EVOH recyclable?

EVOH itself is technically recyclable, but its recyclability in practice depends on concentration. CEFLEX (the European flexible packaging recycling consortium) considers EVOH compatible with polyolefin recycling streams when present at ≤5 wt% in the total structure. Most standard multilayer EVOH structures are within this range. This is a significant advantage over aluminum foil laminates, which are not recyclable in conventional plastics streams. The EU PPWR (Packaging and Packaging Waste Regulation), which includes recyclability requirements phasing in from 2030, is a primary driver behind the industry trend from aluminum foil structures toward EVOH-based transparent alternatives.

Q8: How does Sunkey specify EVOH in its retort pouch structures?

Sunkey Packaging uses EVAL™ (Kuraray) and equivalent grades in transparent retort pouch structures for customers requiring microwave compatibility or product visibility. For standard opaque retort pouches, aluminum foil laminate (PET/Al/CPP or BOPA/Al/CPP) remains the specification due to its superior barrier performance and lower cost at scale. We can advise on structure selection based on your product's oxygen sensitivity, target shelf life, processing temperature, and sustainability requirements. Contact our technical team for a structure recommendation.

Related Articles in This Series

• Blog 3: Retort Pouch Materials Guide: Choosing the Right Structure for 121°C and 135°C — sunkeycn.com/retort-pouch-materials-guide

• Blog 8: EVOH Selection Guide: Ethylene Content, Humidity, and the Sandwich Principle — sunkeycn.com/retort-pouch-evoh-selection-guide

• Blog 10: Transparent High-Barrier Retort Pouches: When and How to Specify Them — sunkeycn.com/transparent-retort-pouch-high-barrier

• Blog 17: The US Army Started Developing Retort Pouches in the 1950s: The Full History — sunkeycn.com/history-of-retort-pouches-invention

• Blog 19: Chemical Recycling of Flexible Packaging: Industry Revolution or Expensive False Promise? — sunkeycn.com/chemical-recycling-flexible-packaging-reality-check

© 2026 Sunkey Packaging Co., Ltd. All rights reserved. | www.sunkeycn.com

Disclaimer: Market share data cited from Kuraray corporate survey (self-reported ~60% share) and third-party market research. Capacity figures are based on publicly announced plans and may differ from actual commissioned capacity. Chinese industry data sourced from Chinese-language industry media; cross-checked across multiple sources. EVOH OTR values are material-level data from Kuraray EVAL technical documentation; laminate-level OTR depends on structure design. This article is for informational purposes only and does not constitute procurement advice.

Blog 18 of 20 | Sunkey Retort Pouch Content Series | Phase 4: Outer Layer | Published 2026