Paper is divided into two categories: "handsheet" and "machine paper". The two are identical in terms of manufacturing principles. The size and productivity of "handsheet" are very limited, and the width of machine paper is wider and wider. The paper of 10 meters wide is not the largest, some are 11 meters wide and the production speed can reach 2000 meters per minute, just like the car driving on the highway 120 kilometers per hour. Therefore, the handsheet can only be used. Small pots and small stoves are used to make some special papers for artistic creation or special purposes. For example, Zhang Daqian, a master of Chinese painting, likes to use smooth and lustrous paper made of pineapple leaf fiber. He called it "Jiansu Xuan" as a kind of Fashion. Master Liu Guosong, the father of modern color ink painting, deliberately incorporated some waste fiber into the pulp, and copied a lot of rough hemp paper on the paper. After painting on it, he manually pulled up the picture. The tassel head is like the white ink effect on the picture, but it is not like it, because some of the silk does not eat ink, and some will infiltrate the ink mark, so the thick burrs that are pulled up will have burrs, and there is no edge. The natural ink is interesting. This is the technique of master Liu in addition to painting on the hand-made papers on the market. In addition, the technique of hand-picked paper is more in-depth, and the unused waste fiber is thrown into the normal raw materials to form a screen of anti-whitening. Come over and reduce the taste of ink. For the printer, the general hand-made paper is too breathable, it is not suitable for inhalation and paper feeding, and the amount of ink absorbed by the rice paper is too much, even the paint treatment will absorb too much ink, which is not good for the ink color. It is lightened and the prints are scattered. However, now that inkjet is coated with a coating material, it can also have a good ink color on the rough fiber surface, so it is not possible to judge the printable or unprintable in a general sense. There are many handwritten papers with high artistic quality, but they are not the focus of this article. Some papers such as watercolor paper, acid-free paper or small-edged hand-made paper are very artistic. They are mostly plain and plain, mostly used for painting. However, in recent years, under the surface treatment, water-based ink can also be used for color spray. The use of UV ink does not require that "machine paper" is mostly used for printing, packaging and household hygiene paper. In addition, there is still a part of "mechanical copying paper" which can be used in less elaborate calligraphy and painting to the bottom of the paper. Machine paper is produced using "single net" or "double-sided net", and more and more high-speed paper machines use double-wire machine for papermaking, which can eliminate double-sidedness. Why is it easy to distinguish between the mesh surface and the felt surface by the single-network machine? The reason is that the pores of the mesh surface are relatively large, which will cause the loss of fine fibrous body, cilia, and even the pulp and paper-making filler produced by beating. On the contrary, on the upper felt surface, only water and a small part of very fine cilia The scorpion is infiltrated into the mesh surface, and most of the cilia, fiber body and filler will remain on the paper surface, so that the paper surface above the felt is smooth and flat, which is different from the single net machine and the double net machine. The gap between the surface is thick and the surface of the felt is thin. Unlike the hand-made paper, there is a curtain net to take over the pulp in the paper-making cylinder. After the sieve is completed, the curtain net will be picked up in a short time from the water surface, so the curtain is lost. Very little cilia, plus extremely wet paper, after being separated from the curtain, stacked on each other to flatten the thickness of the curtain surface and the non-curtain surface. In the era when there was no double-network machine 3 or 40 years ago, it was necessary to distinguish the rough surface of the paper and the thin surface of the felt before printing. The cover used for printing the cover was beautiful, and the cover was printed on the mesh. The quality is a little bit worse, but it can only be made this choice. However, today's high-speed dual-network machines have the function of pressing each other to remove water, and also use double-sided vacuum suction to remove the water copied into the mesh, so there is no distinction between the two sides of consistency!
"Machine paper", as its name suggests, uses mechanized equipment to make long strips of paper, then dry and wind up. Today, not only dry, even coating processing, quality inspection, but also on the paper machine, the paper is finished and processed, but two After the millennium, the principle of papermaking and the standard papermaking process established by Cai Lun have not changed so far. The long materials such as hemp, eucalyptus, eucalyptus, and geese are prepared for high-strength banknotes, art papers, Use of rice paper, or some herbs and wood fiber, need to be sliced, soaked, chopped, boiled (ground pulp is dry-grinded and then boiled), then beaten and smashed (to make the fiber have a certain degree of crushing), from the preparation of pulp , papermaking, pressing, drying to completion. Hand-made papermaking uses a paper-drawing curtain to rotate the pulp fibers in the tank in a rotary manner, so that the paper produced has no yarn flow direction, and the paper machine is made up of a "head box", which will hit only 0.5. ~1.0% of the very thin deuterated pulp, sprayed on a single high-speed forward web or double net, and then squeeze or double-net vacuum to absorb water. In fact, the preparation of pulp often requires not only the slurry ratio of long fibers and short fibers, but also the addition of chemicals, tanning materials or other rubber compounds, mineral kaolin, white clay, porcelain clay and other fillers to improve the combination of paper fibers. The suitability of force, whiteness and writing, printing or other functions is improved. For the "non-coated paper", only the preparation and drying process are prepared. It is remarkable to make a little rosin or other, such as improving the absorption of paper and making the humidity change. Less, the paper surface does not have a very strong capillary phenomenon of Size coating. The other is "coated paper", which is coated with a coating of rubbing powder on the paper. The composition is made up of 2g of "micro-coated paper" on each side and 4g of "light-coated paper" up to 8g. 10g, 12g up to 14g of "advanced coated paper" per side, the coating amount can improve the smoothness, printability, whiteness and reflectivity of the paper surface, but the coating amount is too large, such as There are 14g/m2 coated 126g/m2 paper on both sides, and the base paper only has 98g/m2 left. If it is light-calendered snow paper, it can maintain good stiffness. If it is bright, general glossy coated paper After smoothing the surface by a few stages of high-pressure calendering, the surface is very bright, even with a mirror-like feel, but 126g/m2 of glossy coated paper, unless the base paper is high in stiffness. The base paper is coated, otherwise it will be a very bright but not able to make the book stand up softly, unless it is supported by a hardcover cover, or a small number of pages can be supported by a hard cardboard cover, so the paper The coating amount design is related to the basis weight of the paper itself, and has a considerable relationship with the pressure of the calendering. Light-coated paper and micro-coated paper have little influence on the paper strength due to the small amount of coating. Some mechanical pulps made of wood pulp are used to make magazines for miscellaneous paper, or coating amount. Slightly more than 8g coated "copper paper", the paper made from ground wood pulp is thicker and stiffer, such as 60g/m2 copper paper with 44 g/m2 base paper itself. It can maintain a certain degree of stiffness and brightness when pressed, but the ground wood pulp itself is not durable and easy to yellow, not suitable for advanced publications. The production speed of machine paper is fast, some have reached 2,000 meters per minute, 10 kilometers faster than the highway 110 kilometers. The previous paper machine mesh travels slowly, the paper machine has a shorter length, and now it is getting more and more Long processes such as coating, calendering and quality inspection are all in one go, greatly reducing production costs and processes, increasing paper production capacity and saving manpower. The current high-speed paper machine is 11 meters wide, 2.2 times wider than the domestic 4.9 meter paper machine, twice as fast, and the production capacity is more than 5 times, and less manpower, because of the automatic control and quality stability. The speed of the paper machine in cultural paper can reach 2,000 meters per minute, but the thick cardboard uses several head boxes to spread the pulp, and the speed is slow to accumulate the paper jam of 450g/m2 and 600g/m2. It can reach 1% fiber content, 99% is water and a very small amount of chemicals and fillers. Therefore, recycling and recycling of wastewater after pressing has become an important issue in the paper industry. More than 20 years ago, the domestic A factory used 15 tons of water for each paper, and the B factory only had 12 tons of water. Therefore, the B factory can have a better profit, because not only can it buy 3 tons of water, but the important one is In terms of the proportion of discharged wastewater, in addition to drying and evaporation, the A plant discharges 10 tons and the B plant discharges 7 tons. The B plant can double the available fibers and chemicals in the wastewater to form waste water to remove solids and chemicals. Under the use, it becomes a benefit of less emissions and more recycling. Today's modern coated paper and paper mills have also used their minds in drying, less evaporation of water, less energy consumption, less water discharge, and reuse of many fibers, chemicals, and end-of-pipe water. Only 5-6 tons of water is left in the paper, which is very useful for the shortage of fresh water resources.
There is a silk flow in the papermaking machine. Because the paper structure of the hand-made paper and the machine paper is very different, when the hand-made paper is used to take the bamboo curtain on the pulp in the slurry tank, the circular sieve is used to take the pulp, and the bamboo curtain frame is taken. Once the surface is raised, the rotating pulp stops and no flow is removed. On the contrary, the papermaking paper of the machine paper moves at a high speed in the direction of the drying cylinder. Therefore, the length of the front and rear strips of the fibers on the paper web is smaller than the diameter of the left and right tubular fibers, and the difference is tens of times the length ratio, as a branch. The bamboo poles flowing in the downstream direction of the stream have horizontal and straight branches when the water is launched. After the flow is less than several hundred meters, the horizontal bamboo poles are almost absent, and all are arranged in the direction of the flowing water. Due to the large resistance of the lateral flow, it is automatically guided straight by other straight bamboo poles and flows downstream in the direction of flowing water. In the same way, under the net, the 1% fiber in the pulp solution will be arranged along the flow rate like the bamboo pole in the running water, even if 80% of the water is drained, 19% of the water and 1% of the fiber slurry are left. The force that pulls the fiber parallel to the direction of the water flow will always exist. Therefore, the fibers of most machines will be produced in parallel with the "wire flow" phenomenon in the direction of papermaking. The yarn flow has a significant influence on the printing and processing to the use of paper and paperboard. Therefore, it is packaged, printed and printed. Engineering design often tends to focus on the innate factors of the "wire flow" of machine paper. This section first mentions that the difference between a heavy paper and a handsheet of machine paper is the creation of "silk flow". Basically, the machine paper is made of "web" and then processed. Machine paper from the "head box" began to flow paper pulp fiber and chemical liquid, until the net or double mesh press to absorb moisture, until the dryer is used to dry the steam dryer, collectively referred to as "wet", to the dryer There are some pressures, quite high temperatures, and the high temperature of about 120 °C is used to remove the moisture from the paper to evaporate the water, so that the pulp can be used from a very transparent pulp to a dry white or a little yellow fiber fabric. This one is not dripping. The paper part is called the “cadreâ€, and the paper that the paper is made from the dryer must be baked to a moisture content of only 5% or less, and the paper will become opaque, and it can have a bonding force and then return to contain 6 ~8% by weight of paper is easy to use, there is no problem with stretching, especially lithographic printing, because the lithographic printing plate wet water, too dry paper will cause stretch to wrinkle, but there is no "Dry" is no way to produce "paper strength" that is opaque and interwoven with paper fibers, which is the strength of tear resistance. Therefore, after the paper is dried, some water will be added to increase the humidity of the paper. Will increase the weight of the paper, this paper mill is advantageous because roll mill at the time of selling, based on how many pounds, how many kilograms denominated.
Paper can be roughly divided into "non-coated paper", that is, only pulp fiber pulping, may add a little bit of glue or a little chemical, filler stone, porcelain clay and other elements to improve opacity. And what we usually call "white paper", sometimes to improve the "whiteness", will add a little fluorescent agent to improve the whiteness of ordinary wood pulp. It seems that there is a little yellowish natural color, it feels not so "white." The shortcomings, but the addition of the fluorescing agent has impaired vision, so now the textbook not only does not add a fluorescent agent, but also deliberately adds a little yellow dye to become "Mixed Road Forest Paper." In the non-coated paper, the white paper is the lowest grade. In the past, the wood pulp, straw stalk and bagasse were used as raw materials for printing. The degree of bleaching was not good enough, and it also had a little yellow texture. But today, white newspapers use 100% recycled newspapers and waste paper to deink and boil. Unless the newspaper has been recycled 7 or 8 times, some new straw will be added to make the fiber structure too short. Therefore, in addition to the poor whiteness of the newspaper, almost no drying (very few drying systems) is used for printing, so the newspaper must have good ink absorption, and it will not be folded when printed. Too much fouling. However, after printing the newspapers placed for 2 or 3 days, the ink is still not completely dry, and the dirty fingers will fall off. Uncoated paper is still divided into two different names: "Mold Paper" and "Dow Lin Paper". Daolin Paper is 100% paper made from high-grade wood fiber that is chemically boiled and bleached, because of its "Dawlin". Two Chinese characters, originally thought to be Japanese people using Hokkaido coniferous forest to cook pulp, forming long-fiber, high whiteness, high pulp tear strength of high-grade non-coated paper called "Dawlin Paper", but inquire about Japanese printing industry There is no such thing as "Dowlin Paper". Instead, it uses "Upper Paper", which is English Wood Free Paper, while Wood Free is 100% chemical pulp paper, which is not bleached with groundwood pulp (mechanical pulp). Not only the yellow and wood-containing lignin, resin and other wood fiber cement materials, so it is easy to turn yellow, crisp mold paper, Japan called "medium paper" to distinguish, and medium or paper paper is also called Wood Contain Paper means non-coated paper containing ground wood pulp. If it contains rice straw, wheat straw, reed straw pulp, bagasse, and sorghum stalk, it is also a kind of papermaking. In the 1960s, Taiwan was very popular with straw stalks as raw materials for papermaking, and even 100% of the straw stalks were boiled with incomplete bleaching. Half-bleaching was used to make beige papermaking. The size of the paper changed greatly on the surface of the paper. Gluing treatment, the fitness is still in the available range, but after all, the straw stalk fiber is short, so it is easy to pull the paper hair, about 1,000 copies, 2,000 sheets need to wash a blanket, one day to print the UN propaganda Products, imported from Daolin paper from abroad, printed more than 20,000 sheets in the morning, there will be no paper scraps, paper hair, only know that the quality difference is 100,000 miles, plus the stability of the overprint size, ink absorption, Forest paper is not like straw fiber, it is glued, it is easy to dry and the fiber uniformity is also very good. It can be said that the paper with usual habit is used, and after using Wood Free's Daolin paper, there is a completely different experience. The production of Daolin paper, although better, is not good enough.
Among the uncoated papers, there is a kind of Kraft Paper, which is generally called "kraft paper". Kraft stands for toughness in German. It is made of long fiber wood chips by sulphate cooking. It has no bleaching and strong structure. Tough as cowhide, also as strong as cowhide paper, usually used for packaging paper, bag to bag rope, high-grade kraft envelope, paper bag, waxing as meat, fry Oil-proof kraft paper. The kraft pulp is bleached into white kraft paper, and some of them are calendered into a slightly glossy white kraft paper. As a bag and a bag, especially its toughness is high, but thin and strong enough, but still Pay attention to the direction of the paper flow, because the strength of the horizontal flow is much lower, only 30~40%. There is a kind of "single-light paper" 5, 60 years ago, one side is very grainy and the other side is calendered. Because the paper has a twisting agent and a white earth material, it is formed by a calender roll to form a glossy bright surface such as coated paper, and the strength of the paper adhered to the paper is stronger than that of the general uncoated paper. The use of a "round net machine", because of the um arch design, the body length is shorter, used to make thin paper to toilet paper. Some are not used for printing paper, but for fruit bagging, must have a certain degree of breathability, the structure should not be too tight, can penetrate oxygen, moisture, and help the fruit grow in the bag.
In the non-coated paper for culture, Wood Free is also a substrate for coated paper and coated paper, and is coated from the base paper. In the non-coated paper, there are mold papers containing mechanical pulp, or recycled paper pulp. In today's papers with coated paper, there are also mechanical wastes with recycled wood and recycled pulp. In the national paper standards for the development of paper standards, the paper industry's main paper, Wood Contain, is available from Grade C and Grade B to A and A1. It does not require Wood Free, but the printing industry believes that it can be graded from C to A. Wood Contain's top grade coated paper containing mechanical pulp and recycled pulp base paper, which must retain at least A1 grade, must be coated with 100% Dow Wood Wood Free base paper, and must not contain pulp other than chemical pulp. Books preserve the integrity of data for hundreds of years and hundreds of years. Otherwise, such as non-coated paper for ground wood pulp, miscellaneous paper coated with a small amount of filler, and copper paper (coated paper for magazine printing), turn yellow and crisp after half a year, one year, because of the ground wood Containing lignin, resin, and rosin oil to accelerate the aging and oxidative decomposition of paper fibers, one day, one can not use a coated paper that can retain Wood Free base paper for a long time as an important information printing carrier, nor is it printing. The blessing of the publishing industry, therefore, the chairman ruled to retain the original paper rules for the use of Wood Free for domestic A1 paper.