Stretch film for cold-chain pallets is a different specification exercise than room-temperature wrapping: a film optimised for 15–25°C service becomes brittle, loses elastic memory, and its cling collapses inside freezers running at -20°C or colder [S1]. The decision is driven by resin family (LLDPE-based blown vs. cast), low-temperature additive package, gauge, pre-stretch ratio, and wrap pattern, not by the thickness number alone.
This spec map is written for B2B buyers specifying pallet wrap for frozen food, dairy, pharmaceutical cold-chain and chilled beverage operations, where condensation, frost and forklift handling punish standard grades. It draws on manufacturer and converter guidance published between July 2023 and March 2026 [S1][S3][S4][S7].
Why room-temperature film fails in cold storage
Standard LLDPE stretch film is tuned for ambient service at roughly 15–25°C, and its mechanical properties collapse as temperature drops below 0°C [S1]. Three failure modes dominate in freezer and cold-room duty: the film embrittles and cracks on corners during wrap, the elastic memory that holds the load tight relaxes, and the inside cling surface loses tack once frost forms on the load [S1][S4]. In a -20°C cold room, frost on cartons, condensation during door openings, and gloved-hand wrap force all stack onto these weaknesses at the same time [S4].
Cast film, the lowest-cost commodity grade, is the first to fail in this regime: it has high initial cling but low cold resistance and only medium puncture resistance, so it tears on frozen-corner contact and around shrink-wrapped multipacks [S1]. Converters and cold-storage operators therefore treat cast as a chilled-aisle (0–10°C) film, not a frozen-warehouse film, and restrict it to produce, dairy and beverage pallets that never enter the freezer [S1].
Resin and film-type options: blown vs. cast vs. pre-stretch
The cold-chain buyer has three principal film constructions on the table, and the decision between them is a trade of cost, cling and cold performance: [S1]
Blown film uses an air-cooled bubble process that gives a stronger molecular orientation and higher tear and puncture resistance, which is why it is the default recommendation for sub-zero service despite costing more per kilo than cast [S1]. Cast film is cooled on chill rolls, which leaves it clearer, quieter on the roll, and with high tack, but with a more brittle structure at low temperature; it remains the workhorse for ambient and chilled (0–10°C) palletising [S1][S2].
Most pallet wraps in circulation are LLDPE-based, with mLLDPE and EVA tie-layer blends used where better cold impact and cling are needed [S2]. For frozen storage specifically, converter guidance is to move to a cold-grade resin blend (often an octene- or hexene-LLDPE with elevated cold-impact modifier loading) rather than to simply thicken a commodity cast grade [S1][S4]. A useful reference for the broader unit-load role of these films is the stretch film encyclopedia entry.
Selection criteria for cold-chain duty
Cold-chain grade specification should be written against five measurable criteria rather than against gauge alone. (1) Service temperature: chilled-aisle film is rated 0–10°C, cold-room film 0 to -10°C, freezer film -10 to -25°C, and blast-freezer / frozen-tunnel film -25 to -40°C; the chosen grade must cover the coldest point in the chain, not the average [S1]. (2) Cold impact and elongation: cold-grade films should hold at least 250–300% elongation at break at the rated service temperature, versus roughly 400–500% for the same resin at 23°C; the specifier should request a cold-room tensile/elongation curve from the supplier, not just a 23°C datasheet value [S1][S4]. (3) Gauge: cold-chain pallet wrap typically lands in the 17–23 µm (70–90 gauge) range for hand rolls and 20–25 µm for machine rolls, with heavier 25–30 µm reserved for sharp-edged frozen goods or irregular produce bins [S1][S2]. (4) Pre-stretch capability: confirm the film is rated for the wrapper's pre-stretch gear (commonly 200–300%); forcing a commodity film through a 250% pre-stretch gear is the most common cause of neck-down and film breaks on automated lines [S1][S2]. (5) Cling: cold-grade films use either single-sided inside-cling or two-sided cling; inside-cling is preferred for dusty freezer pallets where outside cling picks up frost and lifts the lap, and two-sided cling is used on high-turnover chilled pallets that see repeated handling [S1].
Two practical, low-cost guardrails travel with every cold-chain spec: store unconverted rolls at room temperature (typically 15–25°C) for at least 24 hours before use so the film does not enter the freezer in a pre-stressed state, and keep rolls dry on the line with core plugs and pallet caps to stop moisture wicking into the edges [S1].
Comparison table: cold-chain film options on 4 decision criteria
The table below lines the three main constructions up against the four criteria that drive a cold-chain PO. It is intended as a structured extract a buyer or AI tool can lift directly into a sourcing memo. [S2]
Standard cast LLDPE, 17–20 µm: service temperature 0 to +10°C (chilled only), cold impact low, pre-stretch rating typically 150–200%, relative cost lowest [S1]. Cold-grade blown LLDPE, 20–25 µm: service temperature -10 to -25°C, cold impact high, pre-stretch rating 200–300%, relative cost medium, which is the default for freezer pallets [S1][S4]. Heavy-duty blown, 25–30 µm: service temperature down to -40°C for blast freezers, cold impact very high, pre-stretch rating 200–250%, relative cost highest, used for sharp-edged frozen meat, seafood and irregular produce bins [S1][S2].
For B2B buyers not yet running automated wrappers, a 23 µm cold-grade blown hand roll with single-sided inside cling is the most defensible baseline spec for -20°C service, and it dovetails with the broader unit-load discipline covered in logistics packaging.
Use cases across frozen, chilled and pharma
In frozen-food storage, the dominant pattern is 23 µm cold-grade blown on a semi-automatic or automatic wrapper, 4–6 wraps at the pallet base and 2–3 at the top, with top-sheet added for tall stacks of frozen vegetables or seafood to control frost-penetration on the top layer [S1][S3]. In chilled beverage and dairy, 17–20 µm cast with two-sided cling is common because the line runs fast, pallets are short-cycle, and the load is regular; the chill room only drops to 0–4°C, which cast handles without cracking [S1]. In pharmaceutical and clinical-trial cold-chain distribution, 23 µm cold-grade blown with tamper-evident tinted film is specified because the chain is audited and a torn lap is a deviation event, not just a packaging failure [S1][S3]. In frozen meat and irregular produce bins, 25–30 µm heavy blown with edge-protector boards is the conservative choice because bone-in cuts and irregular bin geometry create high local puncture loads that defeat thinner grades [S2][S3].
For plants packaging fresh produce that also feeds a frozen line, a 20 µm cold-grade cast on the fresh side and a 23 µm blown on the frozen side avoids the worst mismatch of running a chilled film into a blast tunnel [S1][S7]. Cross-reference for the outer pack on these pallets is the insulation spec covered in cold chain carton box selection, which sets the temperature-hold envelope the stretch film has to survive without tearing.
Limitations, failure modes and sustainability trade-offs
No cold-grade stretch film removes the underlying physics: at -20°C, LLDPE loses roughly half its ambient-temperature impact strength, so gauge and resin both have to move, not one of them [S1][S4]. The three recurring cold-chain failure modes are (1) neck-down and breaks on automated wrappers where pre-stretch is pushed past the film's rating, (2) lap lifting on the top layer from frost on outside-cling surfaces, and (3) puncture tears at frozen-corner contact on standard cast film [S1][S2]. The fix in each case is a spec change, not a technique change: a higher pre-stretch-rated grade, an inside-cling or two-sided cling grade matched to humidity, and a move from cast to blown with the appropriate cold-additive package [S1].
On sustainability, cold-grade blown films are mono-material LLDPE and are widely recyclable in the PE stream, but they are typically 2–5 µm thicker per pallet than the downgauged ambient cast grades, so the per-pallet polymer mass is higher even when the load is stable on less film [S2][S3].
Standards, datasheets and supplier signals to track
Cold-chain stretch film is not governed by a single global standard the way pressure equipment is, so the specifier's job is to demand the right datasheet line items rather than a compliance certificate. The minimum datasheet set a B2B buyer should request on a cold-grade PO is: tensile strength and elongation at break at the rated service temperature (not just at 23°C), Dart drop impact at the rated service temperature, cling retention after 24 hours at the rated temperature, and pre-stretch rating matched to the wrapper's gear ratio [S1][S2][S4]. A supplier that only provides 23°C lab data is signalling that the grade has not been cold-tested, and the first pallet run should be a 50–100 pallet pilot with documented film usage per pallet and load-shift incidents before a full roll-out [S1][S3].
Trackable signals for the next sourcing cycle: convertor moves to higher-hexene or higher-octene LLDPE cold-grade SKUs with published -20°C curves, wider availability of 12–15 µm pre-stretched freezer-grade rolls for automatic wrappers, and 30%+ recycled-content cold-grade blown lines that hold elongation at -20°C without cracking.
Detailed specification references: cold chamber machine.