Heat Sealable PET Film

PET (Polyethylene Terephthalate) film itself is not inherently heat sealable. Its surface is chemically inert and has a relatively high melting point, which makes it resistant to the temperatures typically used for heat sealing. However, PET film can be heat-sealable through various treatments or coatings. Here are some methods used to make PET film heat-sealable:

1. Coating with Heat Sealable Layers: The most common method is applying a thin layer of heat-sealable material, such as LDPE (Low-Density Polyethylene), EVA (Ethylene Vinyl Acetate), or other heat-sealable polymers, onto the PET film. This coating can be applied to one or both sides of the film depending on the application needs. The film’s coated side(s) can then be heat-sealed using standard heat-sealing equipment.
2. Corona or Flame Treatment: Surface treatment methods like corona or flame treatment can increase the surface energy of the PET film, improving its adhesion properties. While these treatments alone do not make PET directly heat-sealable, they can improve the bond strength when the film is laminated with other heat-sealable films or when coatings are applied.
3. Co-extrusion: PET can be co-extruded with other heat-sealable polymers during the manufacturing process. This process involves extruding two or more materials to form a multi-layer film, where the outer layers can provide the desired heat sealability.
4. Lamination: PET film can be laminated with other materials that have heat-sealable properties. This method involves bonding layers of different films together using adhesives or by heat and pressure. The result is a composite film that combines the beneficial properties of PET (such as strength, clarity, and barrier properties) with the heat sealability of the other material.

These modifications significantly expand the applications of PET film, making it suitable for use in packaging where heat sealing is required to create airtight or watertight seals, such as in food packaging, pharmaceuticals, and many other industries.

Heat sealable refers to the property of a material that allows it to be sealed or bonded together using heat and pressure. In the context of packaging materials, such as films or foils, heat sealability is an important characteristic that enables the creation of airtight or watertight seals to protect the contents of a package.

When a heat sealable material is exposed to the appropriate temperature and pressure, usually with a heat sealing device or machine, the material’s surface layers soften and become tacky. As pressure is applied, these tacky layers come into contact and fuse, forming a strong bond upon cooling. This process is commonly used in packaging applications to seal bags, pouches, wrappers, and other types of containers.

Heat sealable materials are widely used in the food industry, pharmaceuticals, medical devices, and many other sectors where product protection, shelf life, and tamper evidence are important. Examples of heat sealable materials include certain plastics (such as polyethylene, polypropylene, and polyester with special coatings), laminates, and some metal foils.

Heat Sealable PET Film is a polyester film that has been treated or coated to allow for heat sealing. This treatment makes it ideal for packaging applications requiring an airtight seal, enhancing product freshness and shelf life.