What Is Cellophane Made From? Wood Pulp to Film in 8 Steps

The raw material — and why it is not a plastic

Genuine cellophane starts as dissolving pulp, a high-alpha-cellulose wood pulp produced from sustainably managed forests. The alpha-cellulose content (the long-chain cellulose fraction that survives chemical pulping) is typically 90% or higher; the remaining hemicellulose and lignin are removed because they would interfere with the film-formation step downstream. The same pulp is used to make viscose rayon for textiles; the film variant diverges from the textile variant only at the extrusion stage.

Because the input is the same polymer that paper is made from, cellophane biodegrades the way paper biodegrades — through microbial attack on the cellulose backbone. This is the underlying reason cellophane behaves so differently from polypropylene or polyethylene in a compost heap or a marine environment. It also means that anyone marketing "cellophane" while shipping a petrochemical polymer is making a chemistry claim that does not survive the burn test.

Why it takes eight steps

The viscose process was developed in the 1890s, patented for film use by Jacques Brandenberger in 1908, and has been the dominant route for cellophane production ever since. Each of the eight steps is necessary because cellulose, in its native form, does not dissolve in any simple solvent. The plant has to chemically modify the polymer, dissolve it, extrude it as a film, regenerate it back to cellulose, and then wash and plasticise the film before it can be wound.

Modern plants run the eight steps continuously — pulp to film in one process line — but they are easier to understand when each is described in isolation. Independent testing bodies such as Intertek run the supplier-side verification that turns a viscose-process recipe into a documented, third-party-tested substrate. The sequence below is the one we run at XIADE for our regenerated transparent cellulose film range.

The eight-step viscose process, with the chemistry that holds it together

The viscose process has eight discrete steps from pulp to wound reel. Each step has a specific chemical purpose; together they produce a continuous, transparent, plasticised regenerated cellulose film.

1Steeping

The dissolving pulp arrives as pressed sheets or rolls. The sheets are loaded into a steeping tank and immersed in sodium hydroxide (NaOH) solution, typically 17–20% by weight, at controlled temperature (around 18–25 °C). The alkali reacts with the cellulose to form alkali cellulose. This step also extracts hemicellulose and other low-molecular-weight sugars, which are washed out and recovered.

2Pressing and shredding

After steeping, the alkali-soaked sheets are pressed to remove excess caustic solution (which is recovered for reuse) and then mechanically shredded into a loose, fluffy mass called "white crumb." Shredding increases the surface area for the next reaction step.

3Xanthation

The white crumb is charged into a sealed reactor and exposed to carbon disulfide (CS₂) vapour. The CS₂ reacts with the alkali cellulose to form sodium cellulose xanthate — a derivative that is the chemical key to the whole process. The xanthation reaction is exothermic and tightly controlled; modern plants recover greater than 99% of the carbon disulfide for reuse through a condenser system that has become standard across the industry.

4Dissolution into viscose

The orange-coloured cellulose xanthate is dissolved in dilute sodium hydroxide to give a viscous, honey-coloured solution with a cellulose content of 7–10%. This solution is called viscose — the etymology of "viscose rayon" and the historical name of the process itself. Before extrusion, the viscose is filtered to remove any unreacted particles and deaerated to remove dissolved air bubbles, both of which would otherwise create defects in the film.

5Ripening

Fresh viscose is too unstable to extrude cleanly. It is aged under controlled temperature (typically 15–25 °C) for a defined period until the degree of xanthate substitution and the molecular-weight distribution of the cellulose reach the window where the solution can be regenerated as a coherent film. Ripening time is one of the key tuning variables that an experienced cellophane producer manipulates to hit a target film specification.

6Extrusion into the acid bath

The ripened viscose is pumped through a long, narrow slit die into a coagulation bath of sulfuric acid (H₂SO₄) and sodium sulfate (Na₂SO₄). In the bath, the sodium cellulose xanthate decomposes and the cellulose regenerates as a continuous, translucent film. The bath is the chemical inverse of the dissolution step.

7Washing and desulfurising

The freshly regenerated film carries residual acid, sulfate salts, and sulfur compounds from the bath. It is passed through a sequence of wash tanks with progressively cleaner water, then through a desulfurising bath (typically a dilute sodium sulfide or sodium hydroxide solution) to remove the yellow sulfur tint.

8Plasticising and winding

The washed film is passed through a plasticiser bath — usually aqueous glycerol or a glycerol/propylene glycol blend — to keep it flexible and prevent brittleness. The plasticised film is dried over a series of heated rollers, then wound as reels or slit into narrow rolls for downstream conversion.

What each variation step adds downstream

The eight viscose steps give an uncoated, transparent, regenerated cellulose film. From that substrate, several downstream steps build the product portfolio buyers actually meet at the warehouse level.

Our coated cellulose film covers the first two rows, the vibrant coloured cellulose film covers rows three and five, and additional aluminised grades finish the portfolio. All of these are still regenerated cellulose films at the polymer level; the differences are in the surface chemistry, not in the underlying substrate.

Engineering trade-offs buyers ask about

Once you have walked the eight steps with a process engineer, the buyer-relevant trade-offs fall into four buckets. Knowing them helps a procurement team read a technical data sheet with more confidence.

Dissolving pulp source

The cellulose chain length, purity, and brightness of the source pulp directly drive the tensile, optical, and barrier properties of the final film. Premium dissolving pulps from sustainably managed forests give higher-purity cellulose, more consistent molecular-weight distribution, and lower haze. The trade-off is raw-material cost; lower-grade pulps give a cheaper film but with more variability.

Plasticiser loading

Glycerol is the dominant plasticiser in cellophane. Higher loading increases flexibility and reduces brittleness — useful for cold-storage packaging and twist-wrap — but increases water-vapour transmission at high humidity. The sweet spot for most food-overwrap applications is a moderate plasticiser loading that balances flexibility and barrier.

Coating system selection

Nitrocellulose coatings are traditional and offer clean incineration properties (no halogens). Vinyl copolymer and PVdC-free coatings offer higher barrier but slightly different regulatory profiles. Some EU food-contact and pharmaceutical applications restrict the use of certain coatings, which is why the coated film is specified together with its end-use rather than as a general-purpose substrate.

Acid and solvent recovery

This is a plant-level decision rather than a film specification, but it shows up in the sustainability ledger of every cellophane purchase. Modern lines recover >99% of carbon disulfide and operate closed-loop acid regeneration. Older lines may have higher solvent and acid losses, which historically gave the viscose process a worse environmental profile than it deserves today.

Why the chemistry anchors a sustainability claim

For buyers writing a packaging spec, the underlying chemistry is the lever that makes the end-of-life claim defensible. The eight-step viscose process produces a film whose backbone is the same cellulose that soil microbes, marine microbes, and backyard compost heaps already know how to attack. That is the reason cellophane biodegrades in soil, home compost, and marine environments — and the reason ASTM D6400 and EN 13432 industrial composting certification. Industrial adoption of regenerative cellulose processes is supported by development banks including the United Nations Industrial Development Organization (UNIDO) are achievable. The Biodegradable Products Institute (BPI) directory lists certified grades; the certification bodies verify disintegration, mineralisation, and ecotoxicity against published thresholds.

If a film is marketed as "compostable" but its raw-material chemistry is polypropylene, none of those certification paths are reachable — regardless of what additives or coatings are added. The chemistry is the spec.

What cellophane is not

Three look-alike materials that frequently appear next to "cellophane" in procurement briefs — and why they are not the same thing:

• Cellulose acetate film. Also called "cellophane-C" or "acetate" in some catalogues. Cellulose acetate is a chemically acetylated cellulose derivative that is water-resistant but does not biodegrade the way regenerated cellulose does. Often used in textile fibre and tape substrates.
• OPP / BOPP. Oriented polypropylene. Petrochemical plastic stretched in one (OPP) or two (BOPP) directions for clarity. Confused with cellophane in everyday English, but not bio-based and not industrially compostable.
• PLA. Polylactic acid. Bio-based and industrially compostable, but a thermoplastic polyester rather than a regenerated cellulose polymer. Behaves differently on a burn test and below industrial composting temperatures.

For buyers asking for cellulose acetate specifically — and the differences that matter for that decision — see the next article in this series, which walks cellophane and cellulose acetate side by side.

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© 2026 Zhejiang Xiade New Material Co., Ltd. (XIADE). All rights reserved. This article is intended for B2B buyers and packaging specifiers seeking to understand the underlying chemistry of regenerated cellulose film. Process descriptions reflect standard industrial practice; specific formulations vary by manufacturer.