Laminated Aluminum Foil Basics

Laminated foil is a thin gauge ferrous and non-ferrous metal laminated to a variety of materials, including polyester (PET), polypropylene (PP), and polyethylene (PE). Foil lamination enhances the integrity of the product and also increases vapor barrier properties. Depending on the specific application, such as water-soluble or non-water-soluble adhesives, foil lamination can be accomplished using a variety of adhesives.

Industries that most often require foil lamination include

Foodservice

Medical and pharmaceutical

Automotive engineering

Fine arts and crafts

Laminated foil rolls are water-resistant and have a wide range of chemical compositions. The opaque bonded foil lamination process is ideally suited for foils used to protect sensitive materials from light exposure.

In addition, superior flavor preservation and extended shelf life make laminated aluminum foil flexible packaging a popular choice for the food production industry.

You have two options when it comes to laminated aluminum foil/paper structures; glue lamination and wax lamination. While both serve the same purpose, laminating one substrate (i.e. foil, paper) to another, each has unique properties that can make or break good packaging.

 Laminated Aluminum Foil

Lamination Basics

Before we discuss the differences between the two bonds, let's start with the basics - how is a lamination made? Lamination is performed using a rotogravure cylinder, impression rollers, and nibble points. The rotogravure cylinder is passed through a tray of glue or wax cycles that are applied to one side of the primary substrate. This substrate then travels to the nip where it is pressed onto a second substrate, which then dries to complete the lamination process. This process produces an adhesive structure that can then be printed in-line.

Gluing

Glue lamination is the most common method used to laminate foil onto paper. The primary glue used is a custom water-based acrylic adhesive for added corrosion resistance to better protect many foods wrapped with this structure.

The main explanation for the popularity of adhesive laminations comes from the economic benefits they offer. On a per-pound basis, glue is slightly more expensive than wax, but it takes nearly 50% more wax to achieve the same bond as glue when laminating. In the final analysis, we found that wax lamination adds about 3-5% to the cost of the structure.

In addition to the economic benefits offered by glue lamination, there are many performance advantages. The glue at its core is stronger than wax and can be most easily modified to provide a damaging bond. In addition to easier strength, the glue offers post-lamination advantages in product environmental conditions. If stored in an extremely hot environment, the glue will bond longer than a wax-based adhesive of equivalent strength.

Wax Lamination

An alternative to adhesive lamination is wax lamination. Wax was originally used for lamination to provide a structure with better dead fold because once it dries, it has no memory and will form a new shape with minimal resistance. For this reason, wax is a popular lamination option for packaging items with sharp edges, such as chocolate bars, because it can be held more tightly to the rigid corners of the package.

Other benefits of wax-based adhesives include creating bonds with better water resistance, faster curing during the lamination process, and easier modification to meet FDA approval. An important drawback to being aware of when using wax as a laminating agent is that it is susceptible to heat during product storage. Typical waxes have to soften temperatures as low as 140°-180°F, and therefore may delaminate if stored under these conditions for extended periods of time. If you want to get more information about the wholesale best laminated aluminum foil price, welcome to contact us.