Importance of using rectangles

The rectangle is a geometric form which occurs infrequently, perhaps never, in nature, but has been long and widely used by mankind in the shaping of materials. By producing machine-made paper as properly rectangular sheets they are intrinsically compatible with printing and duplicating machines - which have always been primarily designed to process flat rectangular sheets, beginning with the Gutenberg press and continuing through to the present-day PC peripheral sheet printer.

Consequently, when mechanically reproducing graphics or text on an envelope the approach best compatible with printing technology is to print on the flat and then cut to shape, crease, gum and fold. In fact when producing a pictorial envelope from a diamond-shaped sheet, or any other geometrically-complex sheet, there is no option but to print before cutting and folding.

A first distinction: envelope, pockets

Envelopes

The shape and size of the flaps define the different envelopes: Straight or pointed closing flaps, elongation of closing or bottom flaps for certain purposes or special flap configurations for easy opening, mechanical insertion, etc.

• Envelopes with straight seal flaps

	straight flap wallet
	Special straight flap envelope for inserting machines

• Envelopes with pointed flaps

Common name for the pointed seal flap which gives the shape of a rhombus

Envelopes with innovative solutions for opening and inserting:

Special envelopes for inserting machines
Inserting machines require special shapes, paper and seals in order to optimize production. The most usual ones are: 1 Trapeze, 2 Straight, 3 Circular, 4 Teide, 5 Teide 2000.

Interior of the TEIDE envelope	Exterior of the TEIDE envelope	The TRAPEZE wallet
STRAIGHT FLAP pocket	CIRCULAR FLAP envelope	The V shaped wallet

Pockets
The way of constructing and folding the product makes a difference between a wallet and a pocket.
As with envelopes, the shape and size of the flaps and the combinations which can be and are usually made with them differentiate the different pockets.