Papers & boards

Cartridge paper

Used for general drawing, often good quality & generally 100 to 135g in thickness. Paper is used for design & technology projects & will take colour from pencils & felt pens without too much leaking to the opposite side of the paper.

Cardboard

Thicker than paper as it is made up of a number of layers, glue or laminated together. Used for packaging.

Duplex board

Used for containers & can contain liquids as it may have a waterproof liner on the inside. It can have a wax feel. This type of card is used by the food industry & consequently recycled card is not used in its manufacture.

Solid white board

Top quality cardboard made from quality bleached wood pulp. It is the best card for printing onto & consequently it is used for hard backed books & more expensive items.

Corrugated board

Often used for packaging large electrical items. These large boxes protect the contents from damage, strong as it is composed of a top & bottom layer & in between there is a triangulated section.

Foil lined board

Good quality cardboard with an aluminium foil lining. This type of container is ideal for ready meals & take away meals as the foil retains the heat & helps to keep the food warm. 

Tracing paper

Allows the designer to copy an existing drawing or shape. It can be useful when there is no need to produce several drawings that are based on the same outline. Tracing paper makes it possible to place one design on top of another to produce a second layer. The original design can be seen under the second drawing.

Watercolours

Can be used with cartridge papers, but to prevent cockling, the papers must first of all be stretched, hence special watercolour papers are available. These provide a good surface texture that will accept acrylics, gouache & pastel, as well as watercolour.

There are 3 main textures available in watercolour papers:

1. Hot pressed papers have a hard, smooth surface.

2. Cold pressed papers have a rougher surface, which enhances the finished image by allowing more of the colour to be absorbed.

3. A third type is rougher than cold pressed paper, having more peaks & hollows (known as tooth) on its surface.

Optical properties

Most important optical properties for papers are brightness, colour opacity & gloss.

Opacity

An opaque paper will allow little or no 'show through' of the image from the other side of the paper. This is one of the most desirable properties of writing & printing papers.

Gloss, glare, finish & smoothness

Gloss refers to surface lustre.

Glare refers to the way paper reflects light.

Finish refers to the general surface characteristics of the paper.

Smoothness refers to the absence of surface irregularities.

Strength & durability

The strength of paper is determined by the following factors:

Strength of individual fibres

Average length of fibres

Strength of bonds between fibres

Structure of the paper

Strength falls away rapidly with the increase in moisture, due to the breakdown of inter-fibre bonding.

Tensile strength

Most papers require a certain minimum strength to withstand the production processes, including printing, embossing & folding, as well as handling.

Bending strength

The thinner the sheet, the more flexible & light it is, conversely the thicker & heavier a paper is, the more stiff it is.

Porosity

Porosity is reduced with the addition of size to the paper. Greaseproof paper is made by beating the paper, resulting in a dense sheet with very little porosity.