Specifying and choosing the correct thermal label
Choosing a lable should be simple, however there are a number of factors relating to the application that need to be considered, which will dictate the type of thermal label and the correct glue to use in the specific application.
Should I use Direct Thermal Labels or Thermal Transfer Labels ?
Direct Thermal Printing
No ribbon required
Labels print only in black, unless they are preprinted with special thermo chromatic ink
Labels have a shelf life of 1 year or less
Labels not prone to sunlight or heat
Labels not prone to friction or abuse
Thermal Transfer Printing
Requires a thermal transfer ribbon
Labels can be printed in colours other than black
Labels have a shelf-life of over 1 year
Labels are subjected to heat or sunlight
Labels are prone to abuse or surface friction
Which adhesive is right for my thermal label application ?
Selecting an adhesive for labels seems like it should be as easy as just picking a label, but there are actually a number of factors that should be considered to ensure the correct adhesive for the long term.
Permanent adhesives are probably the most common type and designed to remain adhered after first contact. Water-based, rubber and acrylic adhesives are all used for permanent labels, however each have their limitations. Water-based adhesives, for example, should not be exposed to moist environments, while rubber adhesives break down when exposed to sunlight. Acrylic based adhesives are most useful for labels that need to withstand time and frequent handling.
Peelable adhesives are designed to allow the label to be removed. However they may leave some residue, so for certain items they may not be suitable.
Ultra-peelable adhesives are a good replacement for peelable labels that need to be applied to items that require labels to be easily removed. A weak adhesion means that if used incorrectly these labels may fall off.
Freezer or frost fix adhesives are designed specifically to be used in extremely low temperatures. While conventional adhesives become ineffective, frost fix adhesives will still adhere at temperatures below -30°C, ideal for food products that require freezing.
Static cling labels do not actually use a traditional adhesive, rather using static charge to stick to extremely smooth surfaces such as glass.
High temperature adhesives are designed to withstand high temperatures for short periods, making them ideal for applications where high levels of heat resistance are required.