We can define the paper formats according to their measures and these are defined in ISO standard 216 one, which in turn includes the standard DIN 476. This applies in most of the world. I there are plenty of measures for the role, but the most used are the Serie A and to a lesser extent Serie B.

In Serie A, the most widely used format is the A4 (210x297mm) or also called "sheet" used in most printers and fotocopiadoras.

Series B is defined for intermediate sizes Series A. For example, the B4 is the intermediate size between A3 and A4.

PVC (Polyvinyl chloride) is extracted from the polymerization of the vinyl chloride monomer. We can classify PVC into two large groups: rigid PVC and flexible PVC.

Rigid: used for the construction of pipes, pipes, containers, tool accessories, parts, blinds, windows, etc.
Flexible: Corrugated tube, traffic signals like cones. irrigation hoses, curtains for refrigerators, footwear, medicina, etc.

This material begins to soften at 80 ° C and to get rid at 140 ° C. Thanks to these and other properties, PVC is a recyclable material.

Among the main features of PVC we find:

• Different degree of hardness.
• Waterproof.
• It does not corrode.
• It is modelable if subjected to high temperatures.
• Good electrical insulation.
It is a very materialessential
• Stable and inert.
• Good mechanical resistance and impact.
• High resistance to abrasion.
• Resistant and lightweight
• Good thermal insulation
• It is odorless, tasteless and innocuous.