paper & board products Flashcards
(13 cards)
list 3 low grade paper & board products
envelopes, leaflets, magazines, letters
list 3 high grade paper & board products
toilet paper, tissues, newspapers, napkins, flyers
what is tetra pak?
A brand that developed a layered card that holds liquid in a water tight containers, without permeating through the card, making it soggy.
why is tetra pak so difficult to recycle?
Contains polymer layers which tend to be non-biodegradable. Also contain many layers which all need to be separated to recycle.
what are the layers of tetra pak?
- polyethylene
- paper board
- polyethylene lammination
- aluminium foil
- adhesive polymer
- polyethylene metallocene
what is the function of each layer in tetra pak?
- protects the product from external moisture, makes it antibacterial
- gives dimensional stability and strength, increases durability
- binding layer
- keeps contents fresher and regulate temperature, oxygen and light barrier
- binding layer
- to seal in liquid contents
flyers
- cheap way to promote a business or product
- often made from cheap, low-grade paper printed on one side only
- bleed-proof gloss paper is perfect for low-cost flyers and leaflets
- sometimes businesses use more expensive and thicker paper when promoting luxury or high-cost items
leaflets
- made using a higher grade paper, in full colour as are more likely to be kept
- often printed on both sides and folded to reduce space they take up.
magazines
Printed on a higher grade, more expensive, glossy paper, and bound into booklet form using either staples or perfect binding.
newspapers
Printed in much larger number and are disposable due to only being relevant for a day so are printed on low-grade paper with no surface finish. Often just folded together with no binding.
food packaging
- different types of paper and board are suited to different types of food packaging
- all packaging should be non-toxic, lightweight and easily disposable
- cardboard must be treated or coated with another metal such as plastic as if untreated it is absorbent
- but it can make it more difficult to dispose of
- corrugated card is sturdy and good at retaining heat so used in pizza boxes
modifying properties + examples
- properties can be enhanced using additives, additives prevent moisture transfer, increase strength, add colour etc.
- parchment paper made by running sheets of paper pulp through sulfuric acid, giving it a non-stick surface
- tissue paper contains wet-strength additives so it retains its strength when wet
- kraft paper is strong and has a high resistance to tearing due to chemicals and processes used during pulping
sizing
- process that provides a protective filler or coating
- reduces absorbencies of paper so the ink dries on the surface of paper rather than seeping through, resulting in a clearer finish
- used in manufacture of boards used for packaging foods that must be kept dry e.g flour
