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

Viscosity - What is viscosity?

Definition of VISCOSITY:

A measure of a fluid's resistance to flow caused by internal friction between neighbouring particles as a fluid is moving. Viscosity depends on the size and shape of a fluid's particles and the attraction between the particles (as well as any attraction between the particles and any surface a fluid touches). A highly viscous fluid will have greater adhesion (attraction between fluid particles and surface particles) and cohesion (attraction between fluid particles); this means that the particles remain closer together and therefore flow slowly. A less viscous fluid has weaker adhesion and cohesion, allowing the particles to spread farther apart, and so flow faster.

In label production and printing, viscosity encompasses a substance's quality of tack (the ability to adhere quickly to a surface) and flow (the ability to spread across a surface). This is particularly important for coatings, adhesive coatings, release coatings, and printing inks, all of which must be able to flow when they are applied to a surface and then adhere to that surface to remain in place.

Three tubes of glue with different levels of viscosity. Viscosity measures a fluid's resistance to flow; a highly viscous fluid will flow more slowly.

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

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