はじめに

Multilayer packaging films are extensively utilized in the packaging industry because of their capacity to offer improved mechanical strength, barrier qualities, and aesthetic appeal. Nevertheless, obtaining compatibility between layers in these films can present difficulties. This article explores the function of tie layer adhesives as a means of guaranteeing compatibility in multilayer packaging films, including the significance of compatibility, selection criteria, application techniques, and potential future developments in this area.

Compatibility in Multilayer Packaging Films Is Important

For multilayer packing films to provide optimal adhesion and cohesion between layers, compatibility is essential. Layer incompatibility can lead to mechanical strength compromise, decreased barrier qualities, and delamination. It may also result in visual problems including color shifts or blur.

Achieving compatibility is crucial to preserving the packaging film’s performance and integrity over the course of its lifetime. Because they serve as a link between incompatible layers, tie layer adhesives are essential in fostering compatibility.

Tie layer adhesives’ purpose

Tie layer adhesives are especially made to help multilayer packaging films’ incompatible layers adhere better to one another. They serve as a layer of bridge, joining disparate materials that would not cling to one another organically. Tie layer adhesives guarantee the integrity and functionality of the packaging film by creating a strong, long-lasting bond. By stopping the flow of gases or liquids between layers, they also aid in maintaining the film’s barrier qualities.

Selection Standards for Adhesives in the Tie Layer

For multilayer packaging films, there are a number of considerations to make when choosing tie layer adhesives. These consist of film production conditions, temperature resistance, flexibility, adhesion strength, and compatibility with the materials being bonded. Tie layer adhesives need to have strong adhesion to the materials they are joining as well as to the layers next to them in the film structure. Additionally, they must be able to survive the temperatures and processing conditions used in the extrusion and lamination processes, which are crucial to the creation of films.

Techniques for Applying Tie Layer Adhesives

Various techniques can be used to apply tie layer adhesives, depending on the particular needs of the packaging film production process. Coextrusion, extrusion coating, and lamination are examples of common application techniques. To generate a multilayer film, coextrusion entails simultaneously extruding many layers, including the tie layer adhesive. Through the use of a die, extrusion coating applies the tie layer adhesive to one or both sides of a substrate. The process of lamination entails joining two prepared layers together with tie layer adhesive. The choice of application method is influenced by a number of variables, including equipment availability, production efficiency, and film structure.

Future Developments in Adhesives for Tie Layers

The goals of continuous research and development in tie layer adhesives are to increase sustainability, performance, and compatibility. The goal of COACE’s research and development is to create tie layer adhesives that have improved adherence to a broader variety of materials, including innovative packaging substrates. Furthermore, new developments in tie layer adhesive compositions are intended to offer enhanced flexibility, temperature resistance, and barrier qualities. Another major priority is sustainability, as evidenced by the creation of environmentally friendly tie layer adhesives that both meet legal standards and have a minimal negative impact on the environment.Polyethylene is the foundation material used in COACE’s W1L, and it is grafted with MAH to inject polar side groups into the non-polar chain. It functions as an adhesive for both non-polar and polar materials. In composite films made of nylon, polypropylene, and polyolefin, W1L can serve as a connecting element. The adhesion between the base resin and the functional layer resin is significantly improved by the interaction between MAH and the amino group of nylon.

with order to guarantee compatibility with multilayer packing films, tie layer adhesives are essential. Achieving compatibility is crucial to preserving the film’s mechanical strength, integrity, and barrier qualities. Tie layer adhesives promote adhesion and cohesion by serving as a bridge between incompatible layers. When choosing tie layer adhesives, compatibility, adhesion strength, temperature resistance, flexibility, and film processing conditions are all important considerations. Lamination, extrusion coating, and coextrusion are examples of application techniques. The goals of upcoming developments in tie layer adhesives are to increase sustainability, performance, and compatibility.