Creado por TotallyJustMe
hace casi 10 años
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A material's reaction to physical forces (Strenght, Plasticity, Ductilty, Hardness, Brittleness), is called what?
Wood is made up of Cellulose fibres that a bound together by...
Which fibres are longer and offer greater strenght?
What happens to the Cellulose fibres to be able to from the mass of individual fibres called wood pulp?
The qualities a material must possess in order to be fit for purpose (the correct: Size, Weight, Grade), is called what?
Which Method of Pulp Production is this?
The logs of ceniferous trees are saturated with water and de-barked. Wood is gound down (Softens Lignin), the mechanised forces separate the fibres to form groundwood pulp. This pulp is screen to accept 1-2mm pieces. The pulp is bleacged with peroxide or sodium hydroxdie.
Resulting pulp can only be used for low-grade paper such as Newpaper.
Paper and Board are produced primarily from what?
The visual and tactile qualities of a material is called what?
Which fibres are shorter, offering a smoother and more opaque finish?
Which Method of Pulp Production is this?
After de-barking the soft and hardwood logs are cut into 2cm chips along the grain. These are pounded into fragments and screened. The pulp in then stored and treated either an acid or alkali to break dron the lignin.
Which Method of Pulp Production is this?
Recycled paper and board is used for lower grades of paper as colour and durability id not as good. This pulp can offern be strenghten by mixing it with virgin fibres.