China Professional Low Temperature Heat Sealable BOPP Film Manufacturer

Low Temperature Heat Sealable BOPP Film is a type of biaxially oriented polypropylene film that features a co-extruded or coated sealant layer designed to form a strong, hermetic seal at temperatures typically ranging from 85°C to 110°C. Unlike conventional BOPP heat seal films that require 120°C to 145°C to initiate a seal, this film allows packaging operations to run cooler, faster, and more efficiently. The lower sealing threshold is achieved through advanced resin formulation and multi-layer co-extrusion technology, which creates a sealant surface with rapid melting and flow characteristics at reduced thermal input.

HUA HENG manufactures this film in a range of thicknesses from 15 to 50 microns, with customizable formulations for specific barrier, slip, and anti-static requirements. The film exhibits excellent machinability on both vertical form-fill-seal (VFFS) and horizontal form-fill-seal (HFFS) lines, as well as on overwrapping and lamination equipment. Its low sealing temperature makes it particularly suitable for packaging chocolate, confectionery, bakery products, fresh produce, and heat-sensitive pharmaceutical or personal care items.

Key Features and Benefits

• Low heat seal initiation temperature: Seals reliably at 85°C to 105°C, reducing thermal exposure for packaged goods and cutting energy use by up to 30% compared to standard heat sealable BOPP films.
• High hot tack strength: Maintains seal integrity immediately after sealing, preventing opening or lifting on high-speed packaging lines where instant seal strength is critical.
• Excellent optical properties: Low haze and high gloss deliver shelf appeal, making printed graphics vibrant and product visibility optimal.
• Consistent coefficient of friction: Controlled slip properties ensure smooth film movement over forming collars, guides, and sealing jaws without jamming or blocking.
• Broad sealing window: Performs consistently across a wide temperature range, giving operators flexibility and reducing rejects caused by temperature fluctuations.
• Superior moisture barrier: Protects dry products from humidity and extends shelf life without requiring additional lamination in many applications.
• Food contact compliance: Formulated to meet FDA and EU food contact regulations, making it safe for direct food packaging.
• Printable and treatable surface: The non-seal side is corona treated for high-quality flexographic or rotogravure printing, with surface tension above 38 dynes/cm for excellent ink adhesion.

Typical Applications

• Confectionery and chocolate wrapping: Low sealing heat prevents chocolate bloom and preserves the temper of cocoa butter, while maintaining high gloss for premium presentation.
• Bakery and fresh produce packaging: The film seals quickly without overheating delicate baked goods or fresh fruits, preserving texture and aroma.
• Heat-sensitive pharmaceutical and personal care products: Protects active ingredients from thermal degradation during the sealing process.
• High-speed vertical and horizontal form-fill-seal packaging: The low seal initiation temperature and high hot tack strength allow packagers to increase line speeds without creating weak or leaky seals.
• Overwrapping for boxes, trays, and cartons: The film’s stiffness and clarity create tight, crisp overwraps with a premium look, while low temperature sealing prevents distortion of thin plastic trays or containers.
• Lamination base film: The treated surface enables strong adhesion to other substrates, making it suitable for multi-layer structures where low sealing temperature is desired on the inner sealant web.
• Ice cream and frozen food packaging: The film remains flexible at low temperatures and seals reliably even when condensation is present, reducing leaker rates.

Packaging and Storage Guidelines

To maintain optimal sealing and optical performance, HUA HENG recommends storing Low Temperature Heat Sealable BOPP Film in its original packaging in a cool, dry environment at temperatures between 10°C and 30°C and relative humidity below 60%. Rolls should be kept away from direct sunlight, ozone sources, and strong solvents. Before use, allow the film to acclimate to the packaging room temperature for at least 24 hours to prevent condensation and ensure consistent friction properties.

Frequently Asked Questions

Q: What is the minimum heat seal temperature ?

A: The minimum heat seal initiation temperature depends on the specific grade and thickness, but for the standard LT-20 transparent film, sealing can begin at approximately 85°C when using a dwell time of 0.5 seconds and a pressure of 2 bar. This is significantly lower than conventional BOPP heat seal films, which typically require at least 120°C. For applications requiring the lowest possible sealing temperature, HUA HENG offers specialty grades with seal initiation as low as 78°C. It is important to note that achieving a strong, hermetic seal requires an adequate combination of temperature, dwell time, and pressure. Our technical team can provide a sealing curve specific to your equipment and packaging conditions.

Q: Is this film food safe?

A: Yes, HUA HENG Low Temperature Heat Sealable BOPP Film is manufactured in compliance with FDA 21 CFR 177.1520 for olefin polymers intended for direct food contact, as well as EU Regulation 10/2011 and its amendments. The film does not contain Bisphenol A (BPA), phthalates, or heavy metals above regulatory limits. When used within the specified temperature range and under normal conditions, it is safe for packaging a wide variety of dry and moist food products, including confectionery, baked goods, snacks, fresh produce, and frozen foods. 

Q: What is the difference between low temperature sealable BOPP film and standard heat sealable BOPP film?

A: The primary difference lies in the sealant layer composition. Standard heat sealable BOPP film uses a polypropylene-based sealant that melts and bonds at temperatures around 120°C to 145°C. Low temperature sealable BOPP film incorporates a modified polyolefin or specialty resin blend in the sealant layer that flows and welds at 85°C to 105°C. This lower activation temperature provides several advantages: reduced energy consumption, less thermal damage to heat-sensitive products, higher line speeds, and the ability to seal on machines with limited heat capacity or inconsistent temperature control. The trade-off can be slightly lower maximum seal strength at very high temperatures, but for most packaging applications the seal strength far exceeds requirements. Low temperature sealable film also tends to have a wider sealing window, making it more forgiving in production.

Q: What is the shelf life of this film after delivery?

A: When stored under recommended conditions—cool, dry, away from direct sunlight and ozone—HUA HENG Low Temperature Heat Sealable BOPP Film retains its full performance characteristics for at least 12 months from the date of dispatch. Over time, the corona treatment level may gradually decline, and the coefficient of friction may shift slightly due to migration of slip additives. For critical printing or high-speed packaging applications, we recommend using the film within 6 months of delivery. Each roll is labeled with a production date and batch number for traceability. Avoid storing the film near strong solvents, such as ketones or esters, which can swell the surface and compromise seal integrity.