Design and Technology in Practice
- Created by: Keanna Hole
- Created on: 08-03-17 11:31
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- Paer and board are produced primarily from hard-and softwoods, although other materials can be used such as cotton, straw and hemp, which produce papers with different properties.
- Wood is made up of cellulose fibres that are bound together by a material that is called LIGNIN.
- In order to make and produce paper, these fibres need to be separated from one another to form a mass of individual fibres called WOOD PULP.
- Softwood fibres are longer, and they offer greater strength, whereas hardwood fibres are shorter, and they offer a smoother, opaque finish.
- Wood pulp is produced by three basic methods, MECHANICAL, CHEMICAL or WASTE.
Mechanical Pulp- Logs of coniferous trees are saturated with water and de-barked. The wood is ground down, which then softens the LIGNIN, and the mechanised forces separate the…
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