What is the Cohesion - What is cohesion??

Also called cohesive attraction or cohesive force cohesion refers to a property of materials that describes the tendency of similar particles within that substance to hold together due to intermolecular forces The cohesive strength of a substance is determined by the shape and structure of its molecules when molecules within cohesive materials get close together the electrons orbiting the molecules are distributed irregularly which creates an electrical attraction that causes the molecules to be attracted towards each other In labelling cohesion is important in the construction of a label from a number of layers and its application onto a substrate while it is important that labels have good adhesion to ensure that the layers within the construction remain firmly bonded together and the labels adhere successfully to a substrate they also need good cohesion to ensure that each layer has the internal strength to remain in its original form even when labels are stressed or put under pressure by the manufacturing and printing processes and during application onto and removal from a substrate Good cohesive strength can also help to avoid common label problems such as adhesive residue and creep also known as cold flow

Glossary

Wicking - What is wicking?

Definition of WICKING:

A property of materials defined as the tendency of a liquid to travel through the material regardless of (and sometimes in opposition to) external forces such as gravity. Also known as capillary action or capillary motion, wicking occurs due to intermolecular forces (or adhesion) between the liquid and the solid surface that surrounds it and the cohesion of the liquid itself, and results in the absorption of the liquid into the material. For example, if the attraction between the surface particles of a liquid and the surface particles of a sheet of paper (and the internal cohesion of the liquid) is great enough, the liquid will be drawn up into the paper, even if the sheet is being held above the liquid. Wicking often occurs in porous materials, such as paper.

In labelling, the absorption of liquids can be both desirable and undesirable. For example, paper used to make labels usually requires some moisture content to produce quality print results and, when using some printing inks, it is vital that the face material is able to absorb the ink to ensure that the print stays in place. However, wicking can also be an undesirable occurrence that results in a face material becoming unstable (because it contains too much moisture) and/or being discoloured by the liquid, or can cause issues with print quality (because the ink has spread throughout the face material).

A demonstration of wicking; wicking is a property of materials that allows liquids to travel through a material regardless of external forces (like gravity). Here the blue liquid travels up the paper towel (against gravity).

Here is the Harvard-style citation to use if you would like to reference this definition of the word wicking:
Label Planet (2020) What is wicking? | Wicking Definition. Available at: https://www.labelplanet.co.uk/glossary/wicking/ (Accessed: January 1, 2024).

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