Surface Treatments and Finishes

Some products are modified to add protection or fix a common problem to keep quality high. This improves functionality and aesthetics.

Paper and board:

-__ Additives__ to help ink dry – To help speed up the rate of printing an additive can be put into ink to help it dry quicker so stacks of printing can be produced without sticking or smearing print.

-__ Embossing__ gives paper a texture by sending it through embossing rollers.

-__ Varnish__ – A top coat of thin varnish on paper or card will create a shiny smooth finish and give it some protection from moisture.

UV varnish – Gives the same protection as varnish but can be applied to spots of paper giving a shiny finish or the whole sheet. It is set with an Ultra violet light. It is particularly useful on paper which will be handled a lot.

Timber and board:

-__ Seasoning__ – Wood that has been cut down is full of moisture and will rot and warp if used straight away. Once stripped of its bark and sliced it has to be stored dry and flat.

-__ Tanalising__ – Outdoor wood needs tantalising to prevent rot. Once seasoned it is dipped in a tank of preservative with the air removed to force the preservative into the grain as deep as possible. It is then dried and ready to use. This will prevent rot and insect damage.

-__ Varnish__, wax and paint – To create a smooth finish and protective layer you can coat your wood. Varnish and wax are see through so keep the grain of the wood visible, paint covers the wood completely. As long as the rough grain is sanded between layers you can make a smooth protective finish.

Metal:

-__ Annealing__ – Heating a metal and allowing it to cool slowly makes a metal ductile and easier to bend without snapping

-__ Dipcoating__ – Heating the metal and dipping it into plastic grains which melt to a smooth finish around it creates a comfortable and less thermo conductive handle.

-__ Galvanising__ – Because ferrous metals rust easily it is galvanised by giving it a protective layer of zinc.

Polymers (plastics):

-__ Ultra violet light__ (daylight) can damage the structure of polymers. Whilst liquid a UV stabilising chemical can be added to stop the degradation. Particularly used in outdoor furniture.

-__ Polymers__ can also be printed on and have vinyl decals made to be glued on. These can protect against rust and be decorative (as in a sign written vehicle).

Edges can be polished to a high shine using fine grit.

Textiles:

Flame retardant spray - Legally soft furnishings and nightwear have to be resistant to fire. They are sprayed with a flame retardant spray.
Dye and ink can be added to the surface of textiles to give decoration. This can be screen printed, applied by rollers or ink jet printed.
Flame proof fibres – Racing drivers and fire fighters require lightweight, cool fabrics (such as cotton) but have flame retardant fibres woven into the fabric.
Anti stain – Additives such as silicone and Teflon can make fabric resistant to stains. This is often seen in school uniforms which need to be hard wearing.
Moisture resistance – Mildew is a sort of mould which can cause fabrics to rot, it thrives in damp conditions. A spray can be added to make a product damp resistant.

Electronics:

Photosensitive PCB board has the surface anodised with aluminium to improve the surface hardness.
Lacquer and lubrication can be sprayed onto PCB’s to avoid damage from moisture.