Bio-based surface treatment of metals
01Overview and value chain
Markers: [EC: EU REACH substance registration | OECD: Industrial biotechnology, Bio-based materials | Regulator: EPA (USA), REACH (EU)]
Bio-based surface treatment of metals replaces part or all of the petrochemical content in rust preventatives, vapor corrosion inhibitor (VCI) films, direct-to-metal epoxy coatings and industrial primers with bio-based oils, resins or lignin, applied to protect steel, aluminum and other metals during shipping, storage or long-term outdoor and marine service. The confirmed producers here span a genuine range of formulation chemistry and product format — Zerust’s biodegradable and compostable VCI films and bio-based rust preventative oils, Verda Shield’s bio-based-resin-plus-graphene epoxy coating, LignoSphere’s lignin-nanosphere coatings derived from forest-industry byproduct, and Baril Coatings’ bio-based industrial primer and topcoat line — rather than one shared chemistry applied by every producer. A useful distinction runs through the category: some products are temporary corrosion protection for shipping and storage (Zerust’s VCI films and oils, designed to be removed before the metal part enters service), while others are permanent, direct-to-metal coatings intended to remain on the part for its service life (Verda Shield, LignoSphere, Baril Coatings) — a buyer should identify which of the two they need before comparing producers.
The key directions of bio-based metal surface treatment are:
- Bio-based and biodegradable VCI (vapor corrosion inhibitor) products: temporary rust-preventative oils and films that release a corrosion-inhibiting vapor during shipping and storage, formulated with biodegradable or compostable chemistry and removed before the part enters service (Zerust).
- Bio-based-resin epoxy coatings for permanent protection: two-component epoxy coatings combining renewable-biomass-derived resins with performance additives (graphene, in Verda Shield’s case) for direct-to-metal, marine-grade permanent corrosion protection.
- Lignin-derived coatings from forest-industry byproduct: coatings built on lignin nanospheres extracted from forest-industry residue streams, targeting the durability, adhesion and corrosion-resistance requirements of metal coating applications (LignoSphere).
- Bio-based industrial primers and topcoats: primer and topcoat systems reformulated with bio-based content to reduce CO2 footprint while maintaining conventional coating performance and film-thickness specifications (Baril Coatings).
Sectoral value chain
[Bio-Based Feedstock Sourcing] ──> [Resin/Formulation Development] ──> [Coating or VCI Product Manufacturing] ──> [Metal Application/Treatment]
│
(Corrosion Performance Testing)
│
▼
[In-Service or In-Transit Protection]Value chain levels
| Level | Description | Key inputs/outputs |
|---|---|---|
| Bio-based feedstock sourcing | Sourcing bio-based oils, renewable-biomass resins or forest-industry lignin byproduct as the feedstock. | In: Bio-based oil, resin precursor or lignin byproduct. Out: Feedstock ready for formulation. |
| Resin/formulation development | Formulating the feedstock into a coating resin, VCI-active chemistry or rust-preventative oil. | In: Bio-based feedstock, formulation additives. Out: Bio-based coating or corrosion-protection formulation. |
| Coating or VCI product manufacturing | Manufacturing the finished coating, film or oil product at commercial scale. | In: Formulation, manufacturing infrastructure. Out: Finished bio-based metal-protection product. |
| Metal application/treatment | Applying the coating, film or oil to the metal surface via spray, dip or wrap application. | In: Finished product, metal substrate. Out: Treated metal surface or part. |
| Corrosion performance testing | Testing the treated metal against salt-spray, humidity or marine-exposure corrosion standards. | In: Treated metal, test protocol. Out: Verified corrosion-resistance performance data. |
| In-service or in-transit protection | The treated metal part is shipped, stored or placed into service, protected by the applied treatment. | In: Treated part. Out: Corrosion-protected part in transit or service. |
Cross-cutting technologies of the sector:
- Temporary versus permanent protection as the core product-format split: VCI-based products (Zerust) are engineered to be removed before service, while epoxy, lignin-based and primer/topcoat coatings (Verda Shield, LignoSphere, Baril Coatings) are engineered to remain on the part permanently — a structural distinction in this category more significant than the specific bio-based feedstock used.
- Diverse bio-based feedstock chemistry with no single dominant route: confirmed producers derive their bio-based content from different sources — biodegradable film polymers, renewable-biomass epoxy resins, forest-industry lignin byproduct — reflecting a category still exploring multiple feedstock routes rather than having converged on one.
- Standard corrosion-testing benchmarks as the shared performance proof point: every confirmed producer substantiates its product against conventional corrosion-resistance benchmarks (marine-grade ratings, extended shipment/storage duration, salt-spray performance) rather than a bio-based-specific metric, since the buyer’s requirement is corrosion protection first and bio-based sourcing second.
02US
The United States hosts two confirmed producers spanning temporary VCI-based corrosion protection and permanent bio-based epoxy coatings.
Temporary VCI protection and permanent bio-based epoxy coatings
- Zerust: produces Natur-VCI, a fully biodegradable and compostable VCI film, alongside Axxanol 46-Bio and related bio-based rust preventative oils, all built on the company’s Intelligent Counter-Corrosion Technologies (ICT) vapor corrosion inhibitor platform for shipping and storage protection.
- Verda Shield: a Texas-based producer of Bio-SAC-S, a two-component epoxy coating combining bio-based, renewable-biomass-derived resins with graphene nanoparticles, rated for C5-M marine-grade direct-to-metal protection on steel and aluminum.
03CN
This screening pass found no confirmed China-headquartered producer of a bio-based metal corrosion-protection product.
Bio-based coating activity found, but not for metal protection
The Chinese bio-based coatings results found this pass targeted indoor/wall-coating applications (antibacterial, formaldehyde-reducing residential coatings) rather than metal corrosion protection, and general metal anti-corrosion product listings found were generic marketplace pages without a confirmed bio-based sourcing claim. This section is left descriptive of that gap; it should be revisited if a China-based bio-based metal-coating producer’s own product page can be directly confirmed.
04EU
Europe hosts a Dutch industrial-coatings manufacturer and a Finnish lignin-technology startup, spanning an established bio-based primer/topcoat line and an early-stage lignin-nanosphere coating platform.
Established bio-based coatings and early-stage lignin technology
- Baril Coatings: a Netherlands-based industrial coatings manufacturer founded in 1982, producing 803BIO SteelKote and related bio-based primer and topcoat systems for extreme corrosion resistance on steel, marketed on reduced CO2 footprint at conventional film-thickness performance.
- LignoSphere: an Aalto University-originated, Espoo, Finland-based startup developing bio-based coatings from lignin nanospheres sourced from forest-industry byproduct, targeting metal-coating durability, adhesion and corrosion resistance; the company closed a pre-seed funding round in 2026 and remains at an early development stage rather than full commercial scale.
05Leading companies and research institutes
| Company / Institute | Country | Key products / platforms | Tech features | Status 2026 |
|---|---|---|---|---|
| Zerust | 🇺🇸 USA | Natur-VCI film, Axxanol 46-Bio rust preventative | Biodegradable/compostable VCI chemistry | commercial |
| Verda Shield | 🇺🇸 USA | Bio-SAC-S epoxy coating | Bio-based resin + graphene, C5-M marine-grade | commercial |
| Baril Coatings | 🇳🇱 Netherlands | 803BIO SteelKote | Founded 1982; reduced CO2, extreme corrosion resistance | commercial |
| LignoSphere | 🇫🇮 Finland | Lignin-nanosphere metal coatings | Aalto University spin-out; forest-byproduct feedstock | pilot |
06Tech stack and innovations
The stack spans two structurally different protection formats — temporary VCI-based and permanent direct-to-metal coating — with producers differentiating primarily by bio-based feedstock chemistry rather than a shared underlying technology platform.
- Vapor Corrosion Inhibitor Chemistry Made Biodegradable:
- Zerust’s Natur-VCI extends the company’s established Intelligent Counter-Corrosion Technologies vapor-inhibitor platform into a fully biodegradable and compostable film format, reformulating an existing temporary-protection product category around bio-based and end-of-life sustainability rather than changing its core corrosion-inhibition mechanism.
- This is a reformulation innovation applied to a mature product category (VCI packaging), distinct from the from-scratch coating chemistries pursued by the permanent-protection producers.
- Performance-Additive Pairing in Bio-Based Epoxy Systems:
- Verda Shield pairs bio-based, renewable-biomass-derived epoxy resin with graphene nanoparticles rather than relying on the bio-based resin alone to achieve marine-grade (C5-M) performance, illustrating that bio-based content and top-tier corrosion performance are being pursued together via a hybrid formulation rather than treated as a performance trade-off.
- This pairing approach is a useful signal for evaluating other bio-based coating claims: check whether the bio-based resin is doing the corrosion-protection work alone or is combined with a conventional performance additive.
- Forest-Industry Byproduct Valorization as an Emerging Feedstock Route:
- LignoSphere’s lignin-nanosphere technology, originating from Aalto University research, converts a forest-industry residue stream into a coating feedstock, a valorization approach distinct from the plant-oil or bio-resin routes used by the other confirmed producers.
- As a pre-seed-stage, Aalto University spin-out, this represents the category’s most technically novel but least commercially mature confirmed direction — worth tracking rather than treating as an immediately deployable option alongside the more established producers.
07Value chains and production pipelines
Industrial pipeline of a bio-metal-surface-treatment product line
┌───────────────────────────┐ ┌───────────────────────────┐
│ 1. Bio-Based Feedstock │ ───> │ 2. Resin/Formulation │
│ Sourcing │ │ Development │
└───────────────────────────┘ └───────────────────────────┘
│
▼
┌───────────────────────────┐ ┌───────────────────────────┐
│ 4. Metal Application/ │ <─── │ 3. Coating or VCI Product │
│ Treatment │ │ Manufacturing │
└───────────────────────────┘ └───────────────────────────┘
│
▼
┌───────────────────────────┐ ┌───────────────────────────┐
│ 5. Corrosion Performance │ ───> │ 6. In-Service or In-Transit │
│ Testing │ │ Protection │
└───────────────────────────┘ └───────────────────────────┘Stage 1: Bio-based feedstock sourcing
The producer sources bio-based oils, renewable-biomass resins or forest-industry lignin byproduct as the feedstock, the stage where each producer’s specific feedstock route diverges.
Stage 2: Resin/formulation development
The feedstock is formulated into a coating resin, VCI-active chemistry or rust-preventative oil engineered for either temporary or permanent metal protection.
Stage 3: Coating or VCI product manufacturing
The finished coating, film or oil product is manufactured at commercial scale, ready for distribution to metal fabricators, shippers or industrial end users.
Stage 4: Metal application/treatment
The product is applied to the metal surface via spray, dip or wrap application, depending on whether it is a permanent coating or a temporary VCI treatment.
Stage 5: Corrosion performance testing
The treated metal is tested against salt-spray, humidity or marine-exposure corrosion standards, generating the verified performance data that substantiates the product’s protection claim.
Stage 6: In-service or in-transit protection
The treated metal part is shipped, stored or placed into service, protected by the applied treatment — the stage where a temporary VCI product is eventually removed before service, while a permanent coating remains for the part’s service life.
| Supplier | Price | Lead time | Certificates | Risk | Confidence |
|---|---|---|---|---|---|
| Zerust | custom | custom | us | Low | HIGH |
| Verda Shield | custom | custom | us | Medium | MEDIUM |
| LignoSphere | custom | custom | eu | Medium | HIGH |
| Baril Coatings | custom | custom | eu | Low | HIGH |
Key directions:
- Identify whether you need temporary protection (removed before the part enters service — Zerust’s VCI films and oils, for shipping/storage) or permanent protection (stays on the part for its service life — Verda Shield, LignoSphere, Baril Coatings) before comparing producers; the two product formats aren’t interchangeable despite both being marketed as corrosion protection.
- Verda Shield’s Bio-SAC-S pairs a bio-based epoxy resin with graphene nanoparticles rather than relying on the bio-based content alone for marine-grade performance — check whether a given “bio-based coating” claim is doing the corrosion-protection work by itself or is combined with a conventional performance additive.
- LignoSphere is the category’s most technically novel confirmed direction (lignin nanospheres from forest-industry byproduct) but also its least commercially mature — an Aalto University spin-out that closed a pre-seed funding round in 2026, not yet at the commercial scale of the other three producers.
Regulatory:
- These products fall under general industrial-chemical substance oversight (REACH in the EU) rather than a metal-coatings-specific regulatory category; buyers should expect standard chemical-safety documentation and industry corrosion-testing standards (salt-spray, marine-exposure ratings) rather than a bio-based-specific certification.
- No confirmed producer holds a dedicated third-party bio-based-content certification beyond its own marketing claims in the sources found this pass; corrosion-performance ratings (like Verda Shield’s C5-M marine-grade classification) are the more independently verifiable claim to check.
Companies not in table:
- Cee Dee Metalloys’ “Bio Zinc” branding was checked directly and dropped: its actual products are zinc and zinc-aluminum thermal-spray wire for sacrificial galvanic corrosion protection, a conventional metallurgical process with no bio-based sourcing claim found on the company’s own site — a branding name that doesn’t match the underlying chemistry.
- Chinese search results for bio-based coatings surfaced real companies, but all confirmed activity targeted indoor/wall-coating applications (antibacterial, formaldehyde-reducing residential paint) rather than metal corrosion protection — a real but off-topic bio-based coatings industry, not a gap in the search itself.
- Daubert Cromwell’s BioNatur VCI film technology surfaced in this search and looked genuine (a real press release on anaerobically biodegradable VCI film), but was not independently confirmed to the same own-domain evidence bar as the four tabled producers this pass and was left out rather than added on a partial read.
Processing note:
- A buyer evaluating “bio-based metal coating” claims should check two things independently: what fraction of the formulation is actually bio-based (versus a conventional resin with a bio-based additive blended in), and whether the corrosion-performance rating is independently verifiable (a named standard like C5-M) rather than a general marketing claim.