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AlOx PET/PA/RCPP High-Barrier Retort Film for PP Trays

HSQY supplies AlOx PET/PA/RCPP high-barrier retort film for PP trays in easy-peel and lock-seal grades for shelf-stable ready meals, soups, sauces, meat, seafood, baby food, pet food and other thermally sterilized products.

The multilayer structure combines transparent aluminum-oxide-coated PET, puncture-resistant PA nylon and a retort-grade cast polypropylene sealing layer. It is designed to provide product visibility, oxygen and moisture protection, mechanical strength and reliable sealing to compatible polypropylene tray flanges.

Depending on the approved laminate structure, adhesive, ink, tray and processing conditions, the film can be developed for commercial retort processes from approximately 121°C up to 135°C. Final performance must be verified using the actual PP tray, food formulation, sealing equipment and complete retort cycle.

What Is AlOx PET/PA/RCPP Retort Film?

AlOx PET/PA/RCPP retort film is a transparent multilayer lidding material developed for food packages that require both high-temperature sterilization and enhanced protection against oxygen, moisture and aroma loss.

AlOx means aluminum oxide. An ultra-thin transparent aluminum oxide layer is deposited onto the PET substrate to improve gas-barrier performance without creating the opaque appearance associated with conventional aluminum foil.

The AlOx-coated PET is laminated with PA nylon and RCPP using a retort-grade adhesive system. The completed laminate must maintain barrier performance, layer adhesion, dimensional stability and seal integrity after exposure to heat, moisture and pressure.

This material is intended for compatible retortable PP trays. It should not be treated as a universal sealing film for every PP, PET, CPET, PE or paperboard container.

How the Multilayer Structure Works

Layer	Main Function	Packaging Benefit
AlOx-Coated PET	Provides transparency, printability, dimensional stability and enhanced oxygen and moisture barrier.	Supports longer shelf-life development while allowing consumers and quality-control teams to view the food.
Retort-Grade Adhesive	Bonds the PET, PA and RCPP layers together.	Helps prevent bubbling, tunneling and delamination during and after sterilization.
PA Nylon	Adds puncture resistance, impact strength, toughness and flex-crack resistance.	Helps protect packages containing meat, seafood, bones or other products with sharp edges.
RCPP Sealing Layer	Provides the food-contact surface and heat-sealing function.	Forms either an easy-peel or lock seal with a compatible PP tray flange.

Easy-Peel and Lock-Seal Retort Film Options

HSQY offers easy-peel and lock-seal AlOx PET/PA/RCPP film grades. The correct option depends on the required consumer-opening experience, food type, fill conditions, leakage risk and retort process.

Film Type	Seal Performance	Typical Applications	Product
Easy-Peel AlOx Retort Film	Provides controlled opening force after the approved retort process while maintaining sufficient seal integrity during processing and distribution.	Consumer ready meals, baby food, medical nutrition and products requiring clean manual opening.	View Easy-Peel Film
Lock-Seal AlOx Retort Film	Creates a strong and substantially non-peelable seal for applications that prioritize leakage resistance and package integrity.	Soups, sauces, liquid-rich meals, seafood, meat products, pet food and transport-sensitive packages.	View Lock-Seal Film

Easy-Peel vs. Lock-Seal Performance

Selection Factor	Easy-Peel Grade	Lock-Seal Grade
Consumer opening	Designed for controlled manual peeling from a suitable tray tab.	Generally opened by cutting, puncturing or tearing.
Primary objective	Balance consumer convenience with retort seal integrity.	Maximize seal strength, leak resistance and tamper evidence.
Critical testing	Pre-retort seal strength, post-retort peel force, peel initiation, shredding and residue.	Pre-retort and post-retort seal strength, burst resistance, leakage and flange-bond consistency.
Typical food profile	Retail meals and products where convenient access is important.	Wet, oily, liquid-rich or distribution-sensitive foods.

Key Benefits of AlOx High-Barrier Retort Film

Transparent high-barrier protection: The AlOx-coated PET layer reduces oxygen and water-vapor transmission while retaining product visibility.
Retort-process resistance: Approved laminate grades can withstand high-temperature sterilization without unacceptable seal loss or delamination.
Post-retort barrier retention: The structure can be developed to maintain the required barrier after the specified thermal process.
Strong puncture resistance: The PA layer helps protect packages containing meat, seafood and other products with sharp edges.
Reliable PP tray sealing: The RCPP layer provides either easy-peel or lock-seal performance with a compatible PP flange.
Clear product presentation: Transparent packaging supports product inspection and premium retail display.
Custom printing: The PET outer layer supports branding, product information, barcodes, QR codes and cooking instructions.
Lightweight construction: The thin transparent barrier layer can reduce packaging weight compared with some foil-based structures.

Reference Product Specifications

The following values are reference commercial options. Final specifications must be confirmed in an approved technical data sheet, sample test and purchase agreement.

Property	Reference Option	Purchasing Requirement
Product type	Transparent high-barrier retort lidding film	Rollstock for compatible automatic or semi-automatic tray sealers
Standard structure	AlOx PET / PA / RCPP	Individual layer thicknesses and adhesive system are application-specific
Transparency	Clear	Specify haze, light transmission and appearance requirements where critical
Seal type	Easy peel or lock seal	Confirm the required pre-retort and post-retort seal strength
Retort temperature	Approximately 121–135°C, grade dependent	Provide temperature, holding time, pressure, counterpressure and cooling conditions
Oxygen barrier	High barrier, grade dependent	Specify the required OTR, test temperature, relative humidity and test method
Moisture barrier	High barrier, grade dependent	Specify the required WVTR and test conditions
Film thickness	Custom according to structure and application	Confirm total thickness, layer construction and tolerance
Standard widths	320 mm, 400 mm and 640 mm	Custom slit widths are available according to the tray-sealing machine
Roll length	Custom	Confirm the maximum roll weight and outer diameter
Core size	Custom	Specify core inside diameter, core material and winding direction
Printing	Gravure or flexographic printing	Retort-resistant ink, adhesive and printing structure must be approved
MOQ	Approximately 1,000 kg per specification	Final MOQ depends on width, structure, printing and raw-material availability
Lead time	Confirm with the commercial quotation	Production starts after structure, artwork and commercial terms are approved

How to Specify OTR and WVTR

The terms “high barrier” and “excellent barrier” are not sufficient for technical approval. Buyers should define measurable oxygen-transmission and water-vapor-transmission requirements.

Barrier Requirement	Information to Confirm
OTR	Required oxygen-transmission rate, test temperature, relative humidity, sample orientation and test method.
WVTR	Required water-vapor-transmission rate, test temperature, humidity gradient and test method.
Test condition	Clarify whether the requirement applies to the AlOx substrate, finished laminate or completed sealed package.
Retort condition	State whether barrier values must be measured before retort, after retort or at both stages.
Shelf-life target	Provide the food type, fill volume, headspace, oxygen sensitivity, storage temperature and required shelf life.

Barrier values measured on the base AlOx film cannot automatically be treated as the guaranteed performance of the final printed laminate or sealed tray. Lamination, slitting, printing, sealing and retorting can affect final package performance.

AlOx PET/PA/RCPP vs. Standard PET/PA/RCPP

Comparison	AlOx PET/PA/RCPP	Standard PET/PA/RCPP
Transparency	Transparent	Transparent
Oxygen barrier	Enhanced by the AlOx coating	Standard transparent-laminate barrier
Typical selection	Oxygen-sensitive products requiring transparent high-barrier packaging.	Products requiring retort resistance but not the enhanced AlOx barrier.
Technical verification	Requires OTR, WVTR and post-retort barrier confirmation.	Requires seal, mechanical and standard barrier confirmation.

Buyers who do not require the enhanced AlOx barrier can review our PET/PA/RCPP Retortable Lidding Film for PP Trays .

AlOx Retort Film vs. Aluminum Foil Retort Film

Property	AlOx PET/PA/RCPP	Aluminum Foil Laminate
Product visibility	Transparent	Opaque
Oxygen barrier	High, depending on the approved structure and converting process.	Typically very high when the foil remains intact.
Light barrier	Limited because the film is transparent.	Provides strong light protection.
Package inspection	Allows visual inspection of the food and fill level.	Internal contents cannot be viewed.
Microwave suitability	Potentially suitable only after the complete package is qualified.	Conventional aluminum foil structures are generally unsuitable for standard microwave heating.
Selection priority	Transparency, product visibility and high barrier.	Maximum barrier and light protection.

AlOx film should not be described as universally equal to aluminum foil. The correct choice depends on the required OTR, WVTR, light barrier, shelf life, retort process and package-handling conditions.

Typical Food Applications

Shelf-stable ready-to-eat meals
Rice, pasta, curry and vegetable dishes
Soups, broths, gravies and sauces
Meat, poultry and seafood products
Beans, legumes and prepared vegetables
Baby food and medical nutrition
Wet pet food and animal nutrition products
Institutional, military and emergency meals
Outdoor and camping food products
Single-compartment and multi-compartment PP retort trays

Compatible PP Tray Structures

The lidding film seals to the polymer exposed on the tray flange. Buyers should provide the complete tray structure rather than describing the container only as a PP tray.

Tray Type	Compatibility Guidance	Validation Focus
Mono PP Retort Tray	May be compatible when the RCPP sealing layer matches the PP flange formulation.	Seal strength, tray distortion, leakage and flange flatness.
PP/EVOH/PP High-Barrier Tray	May be compatible when the exposed flange surface is PP.	Seal-layer compatibility, complete-package OTR and post-retort deformation.
PP/EVOH/PE Tray	Compatibility depends on whether the flange exposes PP, PE or another sealant.	Confirm the exact layer structure and flange polymer.
Filled or Reinforced PP Tray	Mineral fillers, pigments and additives may change sealing and deformation behaviour.	Test actual commercial trays from multiple production lots.

Retort Process Information Required

Retort suitability cannot be determined from the maximum temperature alone. A complete process description is required before the film structure can be approved.

Process Parameter	Information Required
Retort method	Steam, water spray, water immersion, steam-air or another process.
Temperature	Maximum processing temperature and product cold-spot requirement.
Time	Come-up time, holding time and total cycle time.
Pressure	Processing pressure, counterpressure and pressure changes during cooling.
Cooling	Cooling method, cooling time and final package temperature.
Package configuration	Tray size, fill volume, headspace, product viscosity and compartment layout.

The food manufacturer and qualified thermal-process authority remain responsible for establishing a microbiologically safe commercial sterilization process.

How to Select the Correct Film

Provide the following information when requesting film samples, technical evaluation or pricing:

PP tray supplier, product code, layer structure, drawing and physical samples.
Exposed tray-flange polymer, flange width, sealing area and peel-tab design.
Required easy-peel or lock-seal performance.
Food type, pH, oil content, salt content, moisture and oxygen sensitivity.
Filling temperature, fill volume, headspace and possible flange contamination.
Retort method, temperature, holding time, pressure and cooling cycle.
Required OTR and WVTR with complete test conditions.
Required shelf life and storage temperature.
Tray-sealing machine brand, model, tooling configuration and production speed.
Existing sealing temperature, pressure and dwell time.
Film width, roll length, core size, maximum outer diameter and winding direction.
Printing artwork, colors, repeat length, eye marks and transparent-window requirements.
Estimated trial quantity, commercial order quantity and annual demand.
Required food-contact, migration, quality and destination-market documentation.

Recommended Validation Tests

Test	Purpose
Pre-retort seal-strength test	Confirms that the initial seal can tolerate handling and entry into the retort chamber.
Post-retort seal-strength test	Measures seal retention after thermal and pressure exposure.
OTR before and after retort	Confirms whether the laminate maintains the required oxygen barrier after sterilization.
WVTR before and after retort	Evaluates moisture-barrier retention under the approved process.
Lamination-bond test	Detects adhesive degradation, bubbling and delamination.
Leak or dye-penetration test	Identifies channels, incomplete seals and leakage paths.
Burst or pressure test	Evaluates package resistance to internal pressure and handling stress.
Post-retort peel test	Evaluates peel initiation, propagation, film shredding and residue for easy-peel grades.
Print-resistance test	Checks ink adhesion, color change, abrasion and print transfer after sterilization.
Distribution test	Evaluates vibration, compression, dropping and transport performance.

Custom AlOx Retort Film Options

Custom AlOx PET, PA and RCPP layer thicknesses
Custom total film thickness and tolerance
Easy-peel or lock-seal RCPP formulations
Application-specific OTR and WVTR targets
Custom roll width, length, core size and winding direction
Custom gravure or flexographic printing
Retort-resistant inks and lamination adhesives
Eye marks, barcodes, QR codes and coding areas
Transparent windows and custom print coverage
Tray-compatibility and sealing-window testing
Custom cartons, roll labels, pallet marks and export packaging

Quality and Compliance Documentation

Documentation should be confirmed for the exact approved film grade rather than for a general material family.

Technical data sheet for the approved laminate
Certificate of analysis or batch inspection report
Food-contact declaration for the intended market
Migration or compliance reports where applicable
OTR and WVTR reports with test conditions
Pre-retort and post-retort seal-test results
Peel-force test method for easy-peel grades
Roll-width, thickness and visual-inspection criteria
Printing and artwork approval documents

ISO 9001 certification relates to the quality-management system and should not be represented as product-specific food-contact approval.

Why Source AlOx Retort Film from HSQY?

Supply of PP trays, high-barrier films and tray-sealing solutions
Easy-peel and lock-seal retort-film options
Transparent AlOx and standard PET/PA/RCPP structures
Custom roll conversion and printing support
Support for physical PP tray-sample testing
Support for OTR, WVTR and post-retort testing requirements
Quality documentation and export-packaging support
International B2B supply and project-based development

Request AlOx Retort Film Samples and Pricing

Send us your PP tray sample, food application, required OTR and WVTR, retort cycle, seal type, roll dimensions and sealing-machine information. Our team will recommend a suitable AlOx PET/PA/RCPP structure for testing.

Request a Quote

Frequently Asked Questions

What is AlOx PET/PA/RCPP retort film?

It is a transparent high-barrier laminate made from aluminum-oxide-coated PET, PA nylon and retort cast polypropylene. It is developed for high-temperature sterilization and sealing to compatible PP trays.

What does the AlOx coating do?

The transparent aluminum oxide coating improves the film’s resistance to oxygen and water-vapor transmission while allowing the packaged product to remain visible.

What retort temperature can the film withstand?

Approved grades can be developed for processes from approximately 121°C up to 135°C. The final limit depends on the laminate, adhesive, ink, tray, food, process time, pressure and cooling cycle.

Is AlOx retort film completely equivalent to aluminum foil?

No. AlOx provides transparent high-barrier performance, but aluminum foil normally offers stronger light protection and may provide different oxygen and moisture barrier performance. The correct material should be selected using measured OTR, WVTR, shelf-life and processing requirements.

Is the film transparent after retorting?

The film is designed as a transparent structure. Final haze, clarity, print appearance and any color change should be evaluated after the actual commercial retort cycle.

Can AlOx PET/PA/RCPP film seal every PP tray?

No. PP resin grades, barrier layers, pigments, fillers and additives can affect sealing. The RCPP layer must be tested with the actual exposed tray-flange surface.

What is the difference between easy-peel and lock-seal film?

Easy-peel film provides controlled manual opening after sterilization. Lock-seal film creates a stronger and substantially non-peelable closure for products that prioritize leakage resistance and package integrity.

Does the film maintain its barrier after retorting?

Approved film structures are developed to retain barrier performance after the specified retort process. OTR and WVTR should be tested on the final laminate before and after the actual sterilization cycle.

Is AlOx retort film suitable for microwave heating?

Microwave suitability cannot be determined from the AlOx layer alone. The complete film, tray, ink, adhesive, food, venting method and heating instructions must be separately qualified.

Why is PA nylon included in the structure?

PA provides toughness, puncture resistance and impact strength. It is particularly useful for meat, seafood and other products that can place mechanical stress on the lidding film.

Why is RCPP used as the sealing layer?

RCPP is designed to seal to compatible polypropylene surfaces while retaining suitable strength and flexibility during the approved high-temperature retort process.

Can the film be custom printed?

Yes. Custom printing can include branding, product information, cooking instructions, barcodes, QR codes, eye marks and transparent windows. Retort-resistant inks and adhesives must be used.

What OTR and WVTR values are available?

Available values depend on the AlOx substrate, laminate structure, thickness and test conditions. Buyers should provide the required OTR and WVTR together with the test temperature, relative humidity, method and post-retort requirement.

What foods are commonly packaged with this film?

Typical products include ready meals, soups, sauces, curries, meat, seafood, vegetables, baby food, medical nutrition and wet pet food.

Can HSQY provide samples for retort testing?

Yes. Buyers should provide the actual PP tray, food application, retort conditions, seal requirement, barrier target and sealing-machine information so that a suitable trial structure can be selected.

What information is required for a quotation?

Please provide the PP tray structure and dimensions, easy-peel or lock-seal requirement, food type, retort cycle, required OTR and WVTR, film dimensions, core size, printing requirements, order quantity and delivery destination.

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