When you think about labels, the first thought is what goes on the front. Choosing an excellent design for custom label printing is crucial, but it will not benefit if the adhesive on the back is not suitable. Adhesives for pressure-sensitive labels are soft viscous substances that have a sticky feel. When applied on a surface such as a label material, the adhesive will stick to the surface when pressure is used, making the label stick to the intended surface.
Rubber and acrylic are the primary bases that are used in the label printing process. Rubber has a long-term adhesion and goes well with plastic surfaces. However, they can have a yellow tint making them unsuitable for see-through containers, hot and cold temperatures, or an environment exposed to lots of sunlight.
Acrylic labels are UV resistant and work well in hot and cold temperatures. Similar to rubber, they give long-term adhesion though they are not ideal for plastic surfaces.
Flexo labels are applied in three ways. The hot melt application is where a low-cost solution coating rubber-based adhesive is melted and covers the liner with the liquid glue. In emulsion technology, adhesives are suspended in water which then allows them to emulsify on the liner. The solvent coating can be done on both acrylic and rubber bases. It offers a high level of performance and clarity but at an additional environmental cost.
Types of Pressure Sensitive Adhesives
Pressure-sensitive adhesives bond to a label and practically any surface. It does not need solvent, heat, or water to activate.
Acrylic formulations that use solvents are overshadowed by hot-melt and water-based systems. This is due to ecological and economic reasons. Solvent recovery and incineration need to meet the clean air legislation standards. The equipment is expensive and is sustainable in large output operations. They are used in flexo or digital printing of specialty applications such as PVC labels, clear glass looks, and PER labels where optimum water resistance is required.
These solutions are not often used and end up coated with solvents. They are high-performance labels and used on items such as oil cans.
Water-based emulsions have become popular in label stock production since it offers practical in house needs.
Pressure Sensitive Hot-Melts
Hot melt adhesives are growing in popularity because of their durability. They have a strong tack and perform well in wet and cold conditions. When it comes to labeling plastics, they are the most sought after. Hot melt coats quickly on compact equipment and are the most suitable for in-house printers and converters.
The adhesives are cured by ultraviolet radiation or electron beam. The curing process enhances characteristics like the high-temperature performance of bonds.
By understanding how pressure-sensitive adhesive works, you can answer what flexographic printing is. Some substrates stick on board or paper. Pressure-sensitive adhesives have the option of hardy formulations that enable them to bond to complex surfaces like textured plastic containers or wet bottles. They have cohesive strength that makes them disintegrate to minimize tampering.
Please contact Acro Labels Inc. at 1-800-35-LABEL for the best custom label printing available online.