Materials

Materials

1. Paper and Boards

   • Paper
     • Pulp
       • The natural cellulose fibres are mixed with water. This mixture is cooked which produces a fibrous liquid known as pulp. Pulp is fed onto a mesh conveyor which allows excess water to drain away. This makes its way through a series of rollers which help to press, form and dry the pulp into a continuous sheet which is either rolled or cut to size for commercial processing.
     • Treatments and finishes
       • The type of fibre used to make the pulp any chemicals added during the manufacturing process the addition of layers, different coatings or laminates bleaching level which decreases the natural colour so it becomes whiter.
     • Paper weight
       • The weight is measured in grams per square metre (GSM) Understanding the different types of paper available will help you select the right material for the job.
     • types
       • Bleedproof paper
         • When drawing with a marker pen or writing with ink, the paper keeps the ink on the surface which creates a crisper line or mark It resists bleeding and feathering It’s lightweight at around 70-80gsm
       • Cartridge paper
         • It’s used particularly for pencil and ink drawings and paintings Available in a range of weights, a heavier paper at 200gsm is more suitable for watercolour and acrylic painting Would this type of paper be given a coating? Justify your answer
       • Grid paper or isometric grids
         • These are printed with feint lines that enable the user to draw graphs and diagrams, plot mathematical functions or add scientific data Lines can be printed in different weights How does grid paper help with accuracy when drawing a plan, for instance the layout of a new kitchen?
       • layout paper and tracing paper
         • Layout paper is lightweight and smooth with greater opacity than tracing paper It accepts pencil and most other media well
     • Translucency
       • Ranging from 40gsm up to 280gsm for specialist uses It is made in the same way as ordinary paper, but is passed through a bath of acid which partially dissolves the paper This increases the translucency, and it also increases the stability of the paper
   • Boards
     • Types
       • Cardboard
         • Board is measured in microns – 1000 microns equal 1mm Board can be made from recycled paper It can be laminated to other materials to increase strength or provide an alternative surface All of these characteristics make board a very versatile product. Suggest some innovative uses of cardboard?
       • Corrugated cardboard
         • Commonly used for delivery containers and packaging It’s lightweight, but strong With a smooth surface, it can easily be printed on Suggest a common use in the catering industry for corrugated cardboard
       • Foil lined board
         • Cartons containing liquid are foil lined making it food safe The card also has a waxy coating to make it resistant to oils and liquids Where else might you find foil lined card?
       • Duplex board
         • The exterior will have a wax coating to provide a moisture barrier and give it a glossy sheen Its smooth white surface makes it suitable for offset printing Its weight, 200 – 500gsm, also makes it ideal for folding and die cutting Suggest three other household products which would be made using Duplex board
       • Foam board or foamcore
         • Rigid and lightweight, it is often used as a backing material for graphic signage It cuts cleanly with a sharp blade making it very suitable for architectural models or prototypes
       • Solid white board
         • Weights range from 200gsm – 500gsm It’s strong, smooth surface makes it suitable for book covers and product packaging It accepts printing and surface finishes
       • Ink jet card
         • With a special coating this increases the stability of the print A good smooth surface, ensures even ink coverage and absorbency Available in weights ranging from 120-350gsm A matt or gloss coating enables a variety of images to be printed When would a matt finish be more suitable for use?

2. timber

   • Hardwoods
     • Deciduous trees drop their leaves in the autumn and new leaves grow in spring Hardwood is slower growing and is therefore more expensive Sought after for its variety of colours and grains, it has good aesthetical and physical properties It has a closer grain, making it more dense and hardwearing
     • Its deep rich reddish brown hue gives beauty and warmth to furniture, musical instruments, boats and interior panelling Unfortunately man’s desire for mahogany has increased the destructive and illegal logging trade What would be the result of continual illegal logging to the Amazon rain forest? Why is it essential to source wood from sustainably managed forests?
   • Softwoods
     • Most coniferous trees have needles, are evergreen, and they keep their needles all year round Softwood trees grow faster than hardwood trees making it relatively cheap and readily available The grain is wider making it more absorbent What problems could this absorbency cause with the timber?
     • pine
       • light
       • easy to work with
     • Larch
       • durable
       • tough
       • good water resistance
     • spruce
       • has a high stiffness to weight ratio
     • Celdar
       • contans natral oils
       • offers water resistance
   • Manufactured boards
     • Wood pieces are bound together with adhesives to make man-made / manufactured board Manufactured board can be susceptible to moisture Boards are rigid, stable and supplied in large sheets What are the advantages of producing board in larger sheets?
       • Medium density fibreboard or MDF Chipboard or particle board Plywood Very dense board which makes it tough Good compressive strength Made up of alternative rotated layers of glued wood veneers Its smooth surface makes it suitable for veneers and finishes Edges chip easily Available in various forms including marine ply for greater water resistance

3. Metals

   • The word ‘metal’ comes from the ancient Greek word ‘metallon’ which means to mine, excavate or extract from the ground Prehistoric man used metals to make tools and weapons Which common metals would you find in a domestic kitchen?
     • Ferrous metals
       • Iron
         • can corrode(rust)
         • magnetic
       • Steel
         • can corrode(rust)
         • magnetic
     • Non-ferrous metals
       • copper
         • thermaly conductive
         • electrally condivtive
         • ductile
       • Aluminium
         • elecrical ly conductive
         • thermaly conductive
         • reflective
       • zink
         • Brittle
         • resanable conductive propties
         • sinks in water
     • Alloys
       • Brass
         • whare resistance
         • hardness
         • good strengh
       • steel
         • thermaly conductivity
         • resistant to corrotion
         • good yeald strengh

4. Plastic

   • Thermoplastic
     • Thermoplastics are not suitable for use in areas of heat or UV sensitivity A good surface finish can be achieved for superior aesthetics They can be recycled Each time the plastic is reheated it will try to return to its original shape – this is known as plastic memory What are the benefits of reusing plastics?
   • Thermosets
     • able to withstand higher temperatures waterproof when solid, so ideal for use in adhesives a good electrical insulator cannot be remoulded

5. Textiles

   • Types
     • Cotton
       • The mature seed splits open to reveal the fibres Once harvested, the fibres are spun into yarn Cotton is soft, strong and easily washable Name two industries that utilise cotton
     • Silk
       • The shimmering appearance comes from the fibres’ triangular like structure A luxury material, its fine finish is soft and gentle to the touch Silk drapes beautifully and retains its shape well Why do think silk is an expensive textile? What man-made material may be used as a visual alternative to silk?
     • Wool
       • Depending on the source of the wool, it can feel coarse or soft It can be easily spun, woven or knitted Wool is naturally crease resistant and absorbs dyes very successfully Wool absorbs vapours and keeps a layer of dry air next to the skin, which helps retain body heat, keeping you warm What factors make natural fibres renewable and sustainable?
   • Choices
     • Fabric decisions
       • Is it windproof?
       • Is it waterproof?
       • Should it be warm?
       • Where will it be worn?
       • How often will it be used?
       • How can I increase visibility?
       • How can I make it comfortable?
       • How can I make it breathable?
       • How often will it be washed?
       • Should parts be elasticated?
       • How much should it cost?