Molded fiber has already proved that it can replace plastic in some of packaging’s easier jobs.

It can hold eggs.

Protect electronics.

Separate products inside a box.

Form trays, inserts and cushioning structures from pulp.

The harder test begins when the package has to do more than hold its shape.

Can it contain oily food?

Can it tolerate moisture for days?

Can it survive reheating?

Can it directly hold a cosmetic formulation?

And after gaining all of those functions, can it still behave like paper when it reaches the recycling system?

South Korean packaging startup Nanu is trying to answer those questions by making coating technology, rather than pulp molding alone, the center of its expansion strategy.

Founded in 2021, the company produces molded-pulp packaging and containers and says it is now developing applications extending from foodservice into consumer electronics, cosmetics and potentially semiconductor packaging.

Nanu’s approach is significant because it illustrates where the next stage of fiber substitution is becoming more difficult.

The first generation of molded-fiber substitution was largely about shape.

The next generation is about surface functionality.

And surface functionality is exactly where the boundary between “paper packaging” and “composite packaging” can become complicated.

The egg-carton problem is relatively easy

Traditional molded pulp has several characteristics that make it attractive as a plastic substitute.

Wood pulp, recovered paper and plant fibers can be dispersed in water, vacuum-formed over a mold and dried into three-dimensional shapes. Nanu describes both wet-press and dry-forming approaches within its own molded-pulp platform.

For protective packaging, that can be enough.

A mobile phone insert does not necessarily need to hold soup.

An egg tray does not need to stop cooking oil from penetrating its wall for hours.

Once molded fiber moves into primary food packaging or other direct-contact applications, however, its natural affinity for water becomes a limitation.

This is why so much current fiber-packaging development is no longer about the fiber itself.

It is about what goes on top of it.

Nanu says its solution is a water-based coating system that can be applied selectively to molded-pulp surfaces. On its technical website, the company says coating concentration and viscosity can be adjusted locally depending on the functional properties required in different areas of the package.

That is a more interesting proposition than coating every package uniformly.

If functionality can be placed only where it is required, a converter may potentially avoid adding the same amount of barrier material across the entire structure.

But that possibility depends on the chemistry, coating weight and final recycling behavior—details Nanu has not publicly disclosed in sufficient depth to independently assess.

The coating technology has a longer history than the startup

There is also an important detail in Nanu’s technology story.

The company’s current communications present the coating system as proprietary technology, and Nanu may well have continued developing it internally.

But the original technology base has a documented academic origin.

In 2022, South Korea’s Ministry of SMEs and Startups said Nanu had completed a technology transfer from Chungnam National University’s industry-academic cooperation foundation involving a combined coating apparatus and method for applying localized functionality to molded pulp.

The government selected Nanu for a Prime Minister’s Award in a public-technology commercialization competition that year.

That origin matters because it provides more substance than a generic startup claim about an “eco-friendly coating.”

The company is commercializing a defined technical approach to functionalizing molded pulp.

The bigger question is how far that platform can now be pushed.

Greasy chicken is a more meaningful test than it sounds

One of Nanu’s commercial examples is a container developed for Goobne Chicken.

The requirement was not simply to replace a plastic tray with something brown and fiber-based.

The package needed greater resistance to oil and heat and had to tolerate microwave reheating while containing greasy food.

Another application, developed for Hyundai Department Store’s food hall, was designed to prevent fresh food from absorbing moisture for seven days or longer, according to Nanu CEO Lee Yoon-no.

These examples reveal something important about the fiber-packaging market.

Plastic did not become dominant merely because it was inexpensive.

It became dominant because polymer structures can be engineered around specific product requirements with considerable precision.

Different polymers can supply sealability, moisture resistance, grease resistance, toughness, transparency or barrier performance.

For fiber packaging to take meaningful share from plastic in demanding applications, it has to reproduce enough of those functions without reproducing the end-of-life problems associated with complex laminates.

That is a considerably more difficult engineering objective than merely replacing the shape of a plastic container.

Coatings solve one problem and immediately create another

This is the central tension in coated paper packaging.

A coating can help fiber resist water, grease or other substances.

But the coating itself becomes part of the package entering the recycling mill.

European paper-industry guidance has been explicit about this tradeoff for years.

Cepi notes that coatings, laminations and other functional treatments are often necessary because packaging must first protect the product. But those treatments must be designed so they do not interfere excessively with recycling.

The issue is not simply whether something is described as “water-based.”

Water-based describes how a coating is applied or formulated.

It does not, by itself, establish what happens to that coating during repulping.

Paper recyclers care about different questions:

Can the fibers separate efficiently?

How much fiber is recovered?

How much material becomes coarse or fine reject?

Does the coating create tacky contaminants?

Do soluble substances accumulate in process water?

And can the recovered pulp be formed into acceptable new paper?

Cepi identifies repulpability, recovered-fiber yield, screening rejects, stickies and resulting pulp quality among the critical parameters for assessing paper-packaging recyclability.

Those are mill questions rather than marketing questions.

And they become more important as molded fiber moves into higher-performance applications.

A paper sorting mark is useful—but it is not the end of the recyclability discussion

Nanu says it received approval in March allowing relevant products to carry a separate-disposal marking directing consumers to sort them as paper.

That is commercially meaningful in South Korea.

Correct sorting is a prerequisite for any package to reach a recycling process.

But the distinction between collection classification and technical recyclability should be maintained.

South Korea’s official separate-disposal guidance specifically recognizes that packaging can contain mixed materials or materials applied through coating and lamination. The rules define this kind of construction separately and establish how materials should be identified for disposal.

A disposal mark therefore answers an important question:

Where should the consumer put the package?

It does not, by itself, provide all the data needed to answer another:

How efficiently will that package actually repulp in a particular mill?

This distinction matters well beyond Nanu.

As brands move from conventional plastic into coated fiber, the industry will increasingly need to distinguish among:

paper collection eligibility,

technical repulpability,

recovered-fiber yield,

and actual recycling at scale.

Those concepts are related.

They are not interchangeable.

The global market makes the recyclability question even harder

Nanu intends to expand beyond South Korea, including potential business in Japan, Singapore and other markets.

That immediately makes recyclability more complicated.

A package does not become universally recyclable because one country permits it in its paper collection stream.

Collection systems differ.

Sorting technologies differ.

Paper mills differ.

Acceptable non-fiber content differs.

Even within Europe, Cepi recommends referring to national systems when evaluating packaging because collection and recycling infrastructure varies by market.

The 4evergreen alliance has consequently developed different evaluation routes for paper packaging intended for conventional mills, flotation-deinking mills and specialized recycling processes. Its 2026 design guidance specifically addresses polymeric barrier coatings, wet-applied coatings, laminations and other functional layers rather than assuming every paper structure behaves identically.

For a startup pursuing international licensing, this could become an important commercial issue.

The coating that satisfies a customer’s performance requirement in Korea must still be considered against the recycling conditions of the market where the finished package is ultimately sold.

That is a more demanding standard than calling the substrate paper.

Electronics are a logical expansion. Cosmetics are a much harder one.

Nanu is also jointly developing molded-pulp mobile-phone packaging with Samsung Electronics and says it intends to extend its work toward semiconductor trays.

Moving into electronics is not surprising.

Molded fiber has already established a role as a protective packaging material for consumer products because three-dimensional fiber structures can replace some thermoformed plastic inserts and foams.

Nanu’s own technology description lists electronics cushioning among established applications for dry-formed pulp products.

Cosmetics represent a more interesting frontier.

The company says it is working with Amorepacific and L’Oréal on paper containers intended to hold cosmetic contents directly.

That should be treated as a development project, not a commercially proven replacement for conventional cosmetic packaging.

Direct-contact packaging introduces an entirely different level of functional demand.

The package is no longer merely protecting a bottle.

The paper structure itself is becoming the container.

That means the barrier coating ceases to be a secondary feature.

It becomes one of the components determining whether the packaging concept works at all.

If Nanu can commercialize that kind of application while maintaining an acceptable paper-recycling pathway, it would represent a substantially more consequential step than replacing a plastic cushioning insert.

But the information currently available does not disclose sufficient testing data, product compatibility results or commercialization timelines to conclude that this has been achieved.

Agricultural byproducts could differentiate the material—but the formulation matters

Nanu is pursuing another development under the name Deco Mold.

The company says it is incorporating discarded plant-based materials including tangerine peel and spent brewer’s grain into molded products, with commercialization targeted by the end of 2026.

Its current material-development platform lists a wider group of inputs, including sugarcane, bamboo, citrus residues, rice husks, leafy vegetable residues, brewing byproducts, potatoes and green tea.

This is potentially attractive for two reasons.

It can create a destination for low-value agricultural or food-processing residues.

And it can potentially reduce dependence on conventional virgin or recovered-paper fiber in certain molded products.

But the public information does not disclose enough detail to determine the actual proportion of those byproducts in commercial formulations.

That distinction matters.

A package containing tangerine residue is different from a package predominantly manufactured from tangerine residue.

The same applies to brewer’s grain.

The environmental value also depends on what would otherwise happen to those byproducts, how they are processed, how much energy that processing requires and what effect they have on package performance.

“Made with waste” is the beginning of an assessment, not the conclusion.

Nanu’s biggest problem may still be price

For all the technical discussion, one number may ultimately determine how far molded fiber penetrates disposable packaging.

Nanu says its coated molded-pulp containers currently cost more than twice as much as conventional plastic containers.

That is a serious barrier.

Food-delivery packaging, takeaway containers and many FMCG applications operate at large volumes where small differences in unit price become significant annual costs.

Sustainability can influence procurement.

Regulation can alter the economics.

Brand positioning can justify premiums in some categories.

But a material that permanently costs twice as much as the incumbent will face limits in mass-market adoption unless it offers additional value or the incumbent’s economics change.

Nanu’s response is revealing.

Rather than planning to manufacture every exported container in Korea, it is exploring licensing arrangements for local production in markets including Vietnam.

The company says the objective is to reduce unit costs and eventually enter the delivery-container market more aggressively.

That suggests the next stage of molded-fiber competition will not be decided by materials science alone.

Manufacturing geography, licensing, tooling, coating application and production scale will matter just as much.

A technically superior fiber package that cannot approach the economics of thermoformed or injection-molded plastic will struggle to move beyond selected customers.

Revenue growth shows demand, not yet scale

Nanu expects revenue to reach approximately KRW 1.3 billion in 2026, roughly doubling from a little over KRW 600 million the previous year.

More than 98% of its revenue currently comes from business-to-business sales.

Its customer list and development programs indicate that established brands are actively testing molded fiber in applications where packaging performance matters.

That is significant for a company founded only in 2021.

But the numbers should remain in perspective.

This is still a relatively small materials company attempting to prove that its technology can move from customized projects toward repeatable industrial packaging platforms.

Customization is currently one of its advantages.

The company says coating performance is adjusted according to each customer’s requirements for moisture, oil or heat resistance.

At small scale, that flexibility can win projects.

At larger scale, the commercial question changes:

Can customized performance become standardized enough to manufacture economically across many customers?

That is often where promising packaging materials encounter the realities of industrialization.

Molded fiber’s next frontier is not fiber

Nanu’s development path illustrates a broader change occurring across paper packaging.

The first question used to be:

Can paper replace this plastic component?

Increasingly, the answer is yes.

But that exposes a second, harder set of questions.

Can it tolerate water?

Can it resist oil?

Can it run through the customer’s production process?

Can it preserve the product long enough?

Can it meet the cost target?

Can consumers sort it correctly?

And can a paper mill recover enough useful fiber after all the functionality has been added?

That is why coating chemistry may become one of the most important areas in the next generation of fiber packaging.

The coating is what allows molded pulp to leave the egg-carton category.

It is also the component most capable of complicating the recycling story.

The winners therefore may not be companies that make paper imitate plastic at any cost.

They may be the ones that determine exactly how much additional functionality the fiber needs—and add no more than that.

Nanu’s technology is moving into increasingly difficult applications, from greasy food and moisture-sensitive fresh products to electronics and direct-contact cosmetic containers.

That is worth watching.

But its most meaningful achievement will not be another plastic product replaced with molded fiber.

It will be demonstrating, application by application, that performance, price and fiber recovery can survive in the same package.

If those three requirements cannot coexist, paperization simply shifts the problem.

If they can, molded fiber begins to compete in a much larger packaging market than the protective inserts and trays where it first gained traction.

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Last Updated on 14/09/2026 by Jota Machinery