Labeling adhesive is widely used in the food industry, and many manufacturers (including seasoning factories, beverage factories, breweries, etc.) use adhesive to label glass and plastic bottles, explaining product names and detailed parameters.
Currently, there are three main types of labeling glue on the market: oil-based labeling glue, water-based labeling glue, and hot-melt labeling glue. Each of these three properties of labeling glue has its advantages and disadvantages. Today I will mainly share with you several parameters and indicators of water-based labeling adhesives to help manufacturers choose water-based labeling adhesives:
1.The initial bonding strength of labeling glue
When the adhesive on the label and the substrate are in contact with a slight pressure, the force of the adhesive’s adhesion to the substrate is called the initial bonding force of the adhesive. After applying glue with strong initial adhesion to the label, the label can immediately produce strong adhesion after contacting the substrate.
In this way, the label is bonded to the substrate and will not be easily displaced, thereby ensuring the beauty of the packaging. Therefore, to choose a good water-based labeling glue, you must choose a glue with good initial adhesion.
2. Bonding strength of labeling glue
The adhesion the label can achieve when the adhesive penetrates the surface of the substrate is called adhesion. Obtaining bonding strength depends on the bonding strength of the adhesive, the roughness of the substrate surface, ambient temperature, humidity, etc. The time to obtain bonding strength after labeling is 2-24 hours.
Generally speaking, there is no direct relationship between initial viscosity and bond strength. A label with a higher initial viscosity does not necessarily have a higher viscosity. However, according to the actual application of the product, if you need glue with better material breaking effect, you need to require the labeling glue to have strong bonding strength.
3. Low labeling temperature of labeling glue
The low temperature that the adhesive can withstand without losing its bonding function can become the low labeling temperature. The low labeling temperature is determined by the “glass transition point” of the adhesive. Below the transition point, the adhesive gradually crystallizes and hardens into a solid as the temperature decreases.
The lowest labeling temperature for ordinary water-based adhesives is 0°C, and the lowest labeling temperature for resin-based adhesives is -25°C. Therefore, when manufacturers choose labeling glue, they must consider the temperature environment of your on-site labeling.
4. Label usage temperature range
After the label is coated with labeling adhesive and bonded to the substrate, the temperature range in which the adhesive reaches a maximum bonding force without changing its bonding properties is called the label’s use temperature range. For water-based adhesives, the application temperature range is generally between -20 and 120°C, and for resin-based adhesives, the application temperature range is between -40 and 80°C.
The application temperature range is related to the surface material of the label, the surface condition of the substrate, and the ambient temperature. Different adhesives will have different application temperature ranges. However, when manufacturers choose glue, they must consider the ambient temperature of the later finished products to choose which type of labeling glue to use.
