APET is a non-crystalline form of PET. That structure gives it high transparency and good formability, so buyers can inspect fruit, seedlings or seed lots without opening the pack. It is also lightweight compared with glass and stiff enough for stackable trays. For a wider material overview, see our APET plastic sheet guide. For food-focused detail, see APET plastic for food packaging.
The standard range from Haining Hongkai Technology is listed below. The figures come from the company's APET Plastic Sheets product page.
| Parameter | Value | Why it matters on the farm or in the packhouse |
|---|---|---|
| Thickness | 0.2–1.3 mm (±0.015 mm) | Covers thin lids through rigid trays. A tight tolerance gives even wall thickness after forming. |
| Width | 300–1,000 mm (±1.0 mm) | Fits common thermoforming line widths, so there is less edge trim waste. |
| Density | 1.35 g/cm³ (±0.02) | Lets you predict pack weight and freight cost. |
| Max roll weight | 550 kg (±0.5 kg) | Long runs and fewer reel changes in seasonal peaks. |
| Surface resistivity | Normal ≥10¹² Ω; antistatic 10⁹–10¹¹ Ω; conductive 10⁴–10⁸ Ω | Antistatic grades reduce dust pick-up. Conductive grades are mainly for electronics. |
Where APET Is Used in Agriculture
The matrix below links each use to the sheet variant that fits it best. The grade recommendations are our engineering judgment. Confirm them with a trial run on your own tooling.
| Application | Suggested grade | Reason |
|---|---|---|
| Berry, tomato and salad clamshells, punnets and lids | APET Anti-fog Sheet | Packs move from cold rooms to warmer retail air, so clarity must survive temperature swings. |
| Seedling humidity domes and propagation tray covers | Anti-fog, or UV-Resistant APET if sun-exposed | Growers can see the plants without lifting the cover, and dripping condensation is reduced. |
| Farm-shop display domes and sneeze guards | Anti-fog | Steam and humidity around prepared or chilled food. |
| Face shields for cold stores and packhouses | Anti-fog, roughly 0.2–0.5 mm | Breath moisture fogs untreated sheet quickly. |
| Nut, dried-fruit and seed-snack retail trays | UV-Resistant APET | Store lighting can oxidise fats and oils, so UV filtering slows quality loss. |
| Seed and bulb retail blisters | Normal or antistatic grade | Antistatic surfaces attract less dust, which keeps seeds and printed inserts cleaner. |
| Sustainability-led or branded lines | R-PET, BIO-PET or APET Colored Sheets | Recycled or bio-based content and brand colour without changing the forming process. |
The Condensation Trap: What Anti-fog Does and Does Not Do
Anti-fog treatment raises the surface energy of the sheet. Water then spreads into a thin, even film instead of forming light-scattering droplets. The pack looks clear, but the moisture is still there.
Research on berry packaging notes that modified-atmosphere formats can slow product cooling and raise the chance of water condensing inside the pack. A study of strawberries and cherries used an unvented, anti-mist container together with an active pad and a micro-perforated film to manage the in-pack atmosphere. The lesson for sheet buyers is that anti-fog is one part of a system. It does not replace venting, precooling or cold-chain discipline.
Three specification questions that are easy to miss
- Which face is treated? Coatings can be applied to one or both faces. If only one face is treated, make sure it ends up on the inside of the finished lid or tray. Dew on the outside of a cold pack is a separate problem.
- Is it a surface coating or a bulk additive? Bulk additives migrate to the surface over time and last longer. Coatings can be more targeted.
- How will you test it? A common method is placing the sheet over warm water, around 40–50°C, and tracking haze against an agreed limit. For produce, also run a cold-to-warm transfer test that matches your real chain.
Choosing Thickness
Thickness drives stiffness, stack strength, cost and forming behaviour. The ranges below are typical starting points, not guarantees. The right gauge depends on draw depth, tooling and load, so confirm it with a trial.
| Format | Starting range | Watch-out |
|---|---|---|
| Flat covers, thin lids, face shields | 0.2–0.5 mm | Too thin and covers sag or crease when handled repeatedly. |
| Clamshells and punnets | About 0.25–0.5 mm | Corner thinning in deep draws can weaken hinges and locks. |
| Load-bearing trays, propagation trays | About 0.5–0.8 mm | Test with wet compost or produce weight, not empty stacks. |
| Rigid inserts, dividers, display stands | About 0.8–1.3 mm | Heavier gauges need longer heating and precise temperature control. |
Know the Limits: Heat, Sun and Chemicals
The company's documentation puts the glass transition of APET at roughly 75–80°C and its maximum continuous use temperature at about 60–70°C. In practice, a sealed and unshaded enclosure in strong sun can approach that range. Check your worst-case temperature before committing to a grade.
| Situation | Concern | Consider instead |
|---|---|---|
| Hot-fill, ovenable or long exposure above about 60–70°C | Amorphous APET softens and distorts. | C-PET Plastic Sheet; see also the C-PET technical guide |
| Wide swings between very cold and very hot conditions | Standard grades have a moderate temperature window. | High-Temperature & Low-Temperature Resistant PET Sheets |
| Long outdoor exposure | PET's aromatic structure absorbs UV. Yellowing and embrittlement follow over time. | UV-Resistant APET, and request weathering data for your service life |
| Contact with solvent-based formulations | Limited resistance to ketones, esters and halogenated solvents. | Run compatibility tests before choosing any PET sheet. |
The UV-resistant grade is documented as blocking a large share of UVA and UVB light, with light transmittance typically in the 75–88% range depending on grade. This is a trade-off, so specify how clear the pack must remain against how much UV protection it needs.
Food-Contact Compliance for Fresh Produce
In the United States, PET food-contact plastics fall under 21 CFR 177.1630, which sets extractive limits and conditions of use. Compliance for the base resin does not automatically cover every functional grade. Anti-fog and UV additives change the formulation, so ask your supplier for a declaration or migration test report for the exact grade and target market. The EU and China have their own frameworks. This section is general information and not legal advice.
Thermoforming Notes and Troubleshooting
Company guidance suggests drying humid sheet at about 65–70°C for four to six hours, forming at a sheet surface temperature near 120–145°C for many parts, and keeping moulds cool for clear results. APET has a narrower forming window than HIPS or ABS, so precise heater control pays off.
| Symptom | Likely cause | First fix to try |
|---|---|---|
| White haze on formed parts | Overheating or a warm mould causing crystallisation | Lower sheet temperature and keep the mould below about 60°C. |
| Surface blisters | Absorbed moisture | Dry the sheet and store rolls in a dry place. |
| Weak detail or unfilled corners | Underheating or low forming pressure | Raise temperature within the window or increase pressure. |
| Anti-fog seems weak in the finished part | Treated face oriented outward | Confirm the treated side and load the roll accordingly. |
| Inconsistent heat seals | Anti-fog layer changes seal behaviour | Run seal trials and adjust temperature and dwell. |
| Edge cracks or scratches after trimming | Dull tooling | Sharpen or replace cutting tools. |
Store rolls horizontally in a cool, dry place away from direct sunlight and chemical fumes.
Sustainability Options
APET carries resin code 1 and can be recycled in PET streams, provided additives and any coextruded layers are compatible with those streams. Buyers with recycled-content targets can look at R-PET Plastic Sheets. Those wanting bio-based feedstock can look at BIO-PET Plastic Sheets. For multilayer structures, the GAG Sheets range shows what coextrusion can offer.
Quotation Checklist
Send these details with your enquiry so the first sample is close to right:
- Product packed (crop, seed lot, or equipment) and pack format.
- Thickness, width and roll weight targets.
- Functional need: anti-fog, UV, antistatic, colour or recycled content.
- Coldest and warmest temperatures the pack will see.
- Target market and food-contact documents required.
- Forming or sealing equipment used.
Frequently Asked Questions
Is APET suitable for packaging fresh produce?
Yes, it is widely used for trays, punnets and clamshells. Confirm the food-contact declaration for the specific grade you plan to buy.
Can APET replace greenhouse glazing?
It suits small-format covers such as propagation domes. For full greenhouse roofing, ask for accelerated weathering data first, because heat and UV exposure are the main risks.
Does anti-fog sheet stop condensation?
No. It makes condensation form a clear film instead of droplets. Moisture still needs managing through venting, precooling and pack design.
Can I get samples?
The company states that sample rolls are available for trial processing. Contact the team for minimum order quantities and lead times.
