steps in the process of modern paper

paper remained expensive through the centuries, until the advent of steam-driven paper making machines in the 19th century, which could make paper with fibres from wood pulp. 

although older machines pre-dated it, the Fourdrinier papermaking machine became the basis for most modern papermaking. Nicholas Louis Robert of Essonnes, France, was granted a patent for a continuous paper making machine in 1799. At the time he was working for Leger Didot with whom he quarrelled over the ownership of the invention. Didot sent his brother-in-law, John Gamble, to meet Sealy and Henry Fourdrinier, stationers of London, who agreed to finance the project. 

here are the steps:

1. PULPING-forming section, commonly called the wet end, is a continuous rotating wire mesh which removes water from the paper by sucking it out of suspension via vacuum.

2. press section, where the wet fibre web passes between large rolls loaded under high pressure to squeeze out as much water as possible.

3. drying section, where the pressed sheet passes partly around, in a serpentine manner, a series of steam heated drying cylinders. 

4. size-press section, where the semi-dried paper is applied with a thin layer of starch and/ or other chemicals to improve several paper properties reduce dusting and air permeability, increase stiffness, bursting strength and short span compression.

5. calender section: where the dried paper is smoothened under high loading and pressure. only one nip (where the sheet is pressed between two rolls) is necessary in order to hold the sheet, which shrinks through the drying section and is held in tension between the press section (or breaker stack if used) and the calender. extra nips give more smoothing, but at some expense to paper strength.

6. reel section, where paper coming out of the machine is wound onto individual spools for further processing.

Voila!