Old books that have been left behind in the book of the house, old papers stored in the storeroom, or pages of books bought from the old book store, are like yellow hues, have you ever noticed? The bright white book leaves turn yellow in time or some yellow halo, with this event almost everyone is familiar. But why this happens, only a few people think of it. Many people do not even know that it is possible to prevent yellowing of book leaves. And to know these things, you need to know about the development of the paper used in the book. The reason that paper is currently being produced is not such. And with the process of paper production, there is a direct relationship of yellow paper to paper.
Most historians say that China is the origin of the paper. It is estimated that around 100 BC, paper was started in China. Initially, the main ingredients for making paper were wet beans. A trunk of trees was prepared with a trunk of bark (shal), bamboo and a few species of fishes. The stereo was fine, the paper quality was as good as the standard.
The Chinese did not take much time to spread this invention around Asia. But it took a lot of time to reach Europe. Paper production in Europe began in the eleventh century. Historians believe that the Spanish book Missile of Silas is the oldest document in Europe. And this book is also the eleventh century. However, the paper was not like the first paper of the Chinese paper at all. The silks are made from jute fiber. After the invention of Gutenberg printing press, there were some changes in the form of paper production. The paper used to be made of jute fiber in combination with cotton, tangy cloth and other fibers.
The biggest change came in the 19th century. When Charles Fennarti, the inventor who lived in Nova Scotia, Canada, did business in paper. He has been trying to produce long-term paper for a long time. Alongside the paper business, he was also involved in the trade of wood. The use of timber for the production of wood from the wooden business came to his head. Keeping in mind the availability of wood and low prices, he invented a method of producing paper from wood.
In October 1844, Fennarty made the paper with the first wood. Some samples of that paper were sent to the city's most famous magazine 'The Acadian Recorder'. He wrote in a letter to the long-term, sustainable and low-cost quality of his new production paper. The magazine eagerly accepted Fannatti's new paper. From that to the start of paper production of wood.
Not to mention a particular information at this stage. Most historians now remember German inventor Frederick Keller for the production of paper with wood. But the process of production of paper with wood was originally invented by Fennarty. In contemporary times, Keller invented a process of paper production by doing research independently. But the difference creates patents. In 1845 Keller received a German patent for her paper made. And the fender feathery feathery!
We know the historical background of the reason behind the color of the paper being yellow. Let's start chemical talks now. Cotton or jute, wood is cheaper and more available than both materials. Paper made from wood was also long-term than paper.
But the problem was sunlight and oxygen. Wooden paper was damaged quite well in the air and sunlight. The reason for this is hidden in wood. The wood is mainly made from two components. One is cellulose, the other is liginin. Cellulose is the most available organic material in nature. At the colorless and opaque, the object absorbs almost entirely of light falling on it and reflects a small part. The result shows white to see cellulose.
Cellulose is a chemical quality, it is oxidative. As a result, sunlight retains cellulose due to the absorption of sunlight. The fact that the oxidation occurs is the emission of some electrons. This process of emitting electrons quickly weakens the paper. Once its luminosity also decreased. With the decrease of the luminosity, there is little to become Holudov, but the real hostility is Liginin.
Liginin is a complex organic polymer that is common in plants of many different plants. The walls of the cell are solid and strong for the liginin. On paper, Lignin also performs the same duties. If you do not cement it with bricks, sand and stools to build the building, it will never bind it tight, as well as the cellulose fibers will not be together when there is no liginin on cellulose on the paper.
But Liginin can not have a bright color like cellulose. Leganine color is black. That's why the hardboard or cardboard color is black. Because it is used more tightly to make it more difficult to change which color changes. However, the main problem is that, Leganine is also active coagulation chemical. It is susceptible to sunlight, and molecular structure changes. As a result, the wavelength of light in the spectrum of light reflected by Leganine changes. The modified wavelength is located between the wavelength of green and yellow light. In most cases it matches the wavelength of the yellow light and the leaves of the book are yellowish.
Let's analyze a bit more deeply. Ligin is a polymer. Polymer is formed by the common complex mechanism of the same molecule. Above is a diagram of the chemical composition of Leganine. It turns out that the recurrent molecule of the liginin is Alcohol. Now alcohol contains several oxygen molecules.