Adhesive Solutions from Which the Solvents Escape before Bonding

Adhesive Solutions from Which the Solvents Escape before Bonding 

This group includes heat-sealing adhesives and high-frequency (HF) sensitive heat-seal coats these are coating adhesives that are heat-activated during bonding. Contact adhesives and pressure-sensitive adhesives bond by the same principle but without the action of heat. 

Heat-sealing adhesives are applied to the materials to be sealed in the form of solutions, emulsions, or, preferably, in melt or powder form. The solvent-free layer is intended to be nontacky and only to melt and to wet the adherent under the action of heat during sealing. Solidification takes place after cooling. In many cases, sealing is carried out on a coating-to-coating basis. 

High-frequency sealing auxiliaries generally contain vinyl chloride copolymers in addition to proportions of other polymers, such as polyacrylates, vinyl acetate copolymers, plasticizers, and resins. High-frequency heatable coatings have solids contents of 

The highest strengths are obtained with a uniform, thin coating of adhesive coupled with a high contact pressure. It is important to allow for adequate evaporation of the solvents and to observe the open time of the contact adhesive. 

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