To many people that I have come across in and out of printing and graphic industry this word is a puzzle and misnomer. Holding a piece of photocopy paper while scratching their heads , asking themselves can this be really free of wood?
To understand fully we need to back track on how it is made. Paper is made from pulp which is extracted from wood .Wood by itself is natural contains ingredients from mother nature that enable it to mature from a tiny seedling to a full grown tree ready for harvest for paper or furniture. One of these ingredients is lignin. Lignin is the glue that binds all the celullose fibres together in the tree. This adhesive in particular turns yellowish when exposed to light. Remember the other day you left your Star in the back of your car baking in the 36 degree celsius ; you came back to a golden yellow newspaper.
Woodfree on the other hand does not change color in the light. This because it is made from pulp that is free or mostly free of lignin. A lignin free pulp is a result of a chemical pulp making process which uses chemicals [the chips are 'cooked' by heat and pressure in caustic soda and sulphur] to clean the impurities especially lignin. So woodfree is made of chemical pulp.
At the opposite end there are others who want or at least do not mind lignin in the paper like newsprint (for newspaper).A lignin containing pulp is pulp made from a mechanical process. This process is just crushing the wood physically to remove the impurities but much lignin remains. So newsprint and mechanical paper are from mechanical pulp.
At the opposite end there are others who want or at least do not mind lignin in the paper like newsprint (for newspaper).A lignin containing pulp is pulp made from a mechanical process. This process is just crushing the wood physically to remove the impurities but much lignin remains. So newsprint and mechanical paper are from mechanical pulp.
Back to square one,why call it woodfree and not lignin free or mechanical pulp free?. A likely explaination is that the word "woodfree" is a shortened version of groundwood free, a mouthful. Groundwood is mechanical pulp.[logs can be pressed against grindstones which is why this process is also known as ground wood pulp]
But terminology is cultural. In the USA woodfree is always called free sheet. In some countries woodfree is called fine paper but some of the bargain woodfree papers that get imported into Malaysia is anything but fine! . And then oddly, in our local market for some unknown reason woodfree is called "simili" paper. Somebody enlighten me, please.
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