1.1 Performance of Paper and Card Flashcards
What are paper and board made from?
cellulose fibre
What are the sources of cellulose fibres?
- flax
- hemp
- straw
- cotton
- bamboo
- wood
What are the main paper properties?
- whiteness
- opacity
- strength (does it resist tearing)
- absorbency
- finish (matte, satin, gloss or texture)
- cost
What are sizing agents?
Chemicals are added to the pulp or sprayed and rolled to the base paper which reduces absorbency
Why is paper coated?
It reduces ink absorption which results in brighter, richer and sharper images
Why is some paper not coated?
To allow a greater and faster absorption of water or ink
What are the 4 factors tear resistance depends on?
- The way the cellulose fibres bond to each other
- The strength of the cellulose fibres
- The length of the cellulose fibres; longer being stronger
- The number of fillers used; more fillers mean less strength
What is the most widely used tear resistance test used for paper and board?
The Elmendorf Tear Test
What can a die cutter do to paper and board?
Paper and board can be cut, scored, perforated and creased in one action with a die cutter
What is creasing/folding?
Making a line that is permanently present after the material has been creased or folded
What is the difference between cutting and scoring?
Scoring is the same process as cutting but the blade doesn’t go all the way through the material as less pressure is used
What are perforations?
Small cuts in a paper or board which allow portions to be folded or torn off with good accuracy
