The Role of Wax Emulsion in the Field of Water-based Sealing Adhesives

    Sealing adhesive is used to fold and form printed and die-cut cardboard, then seal it with adhesive, and is widely used in cosmetics, medicine, food and other industries.

    Water-based wax emulsion has strong adhesion to non-polar materials such as PP and PE because it has the same chemical composition as them. This characteristic is utilized when adding water-based wax emulsion in the production of water-based PP adhesive.

    Water-based wax emulsion is widely used in the field of water-based sealing adhesive, and its main functions are as follows:

    1. Improve the high and low temperature resistance and water resistance of the adhesive layer to prevent glue failure caused by changes in environmental temperature and humidity.

    2. Since OPE and MAPP have similar structures to non-polar polymers such as PE and PP films, the adhesion of the sealing adhesive to plastic films, water-based varnishes, etc. is increased, and good affinity to plastic films is provided.

    3. The wipeability of spills is improved.

Precautions for the use of water-based wax emulsion:

    1. Water-based tackifying resin requires an acid value between 20-30; an excessively high acid value will cause the system to gel. Low acid value tackifying resin can also be dissolved with solvents such as toluene and then emulsified and added. The tackifying resin requires a softening point between 70°C and 90°C.

    2. Water-based wax emulsion is stable under alkaline conditions. If a strongly acidic acrylic emulsion is used, the system must first be adjusted to weakly alkaline with ammonia water before adding the PE emulsion; otherwise, gelation and particles will occur.

    3. If an alkali-thickening thickener is used, it is recommended to dilute the thickener with water first and add it under stirring; otherwise, particles will form.

    4. It has good compound stability when used together with VAE emulsion, rosin emulsion and tackifying resin systems, and is particularly suitable for packaging films (BOPP film, PE film, etc.) and edge sealing adhesives for water-based coated paper.

    Adhesion is the most important function of glue and the main dividing line between high-quality and inferior adhesives. Inferior glue can only bond firmly for a short time and is prone to degumming under changing environments, while high-quality glue can maintain strong adhesion for a long time under harsh conditions.