What is the Moisture Content - What is moisture content??

A measure of how much moisture or water is contained in paper Paper has a strong affinity for water because it is made up of cellulose fibres that are hygroscopic the fibres readily absorb or release water in order to gain equilibrium with the humidity of the environment Moisture content is expressed as a percentage of the original weight of the paper The dimensions lay flat conductivity strength and printability of paper can all be affected by moisture content Fibres expand or contract as they absorb or release water - more so in width than in length - meaning that the paper will be altered most clearly against the grain The grain is often more pronounced on the wire side meaning that moisture content will also change unevenly causing the paper to curl Dry paper will tend to tear more easily and is likely to produce poorer print results particularly with toner which may not bond properly to dry paper

Glossary

Humidity - What is humidity?

Definition of HUMIDITY:

A measure of the amount of water vapour in the air. It is important to control the humidity of an environment during the manufacturing process, the printing process, and final use, as water can influence the properties of any of the materials used in label products. It is particularly influential in terms of the moisture content of materials, such as paper, that are used to make the face material of labels. Humidity is measured in terms of either the specific humidity (ratio of the mass of the moisture vapour to the total mass of air and water vapour), the absolute humidity (the mass of water vapour), or the relative humidity (the amount of water vapour expressed as a percentage of the total water vapour that could be held at that particular temperature).

Condensation on a film of clear polyethylene; environments with high humidity can result in condensation (water vapour turns into liquid).

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

Go Back to Glossary