Paper

Some manufacturers, notably AMD, have started using a new, slightly more environmentally friendly alternative to expanded plastic packaging made out of paper, known commercially as "paperfoam." The packaging has very similar mechanical properties to some expanded plastic packaging, but is biodegradable and can also be recycled with ordinary paper. Fossils of seed ferns such as Glossopteris are widely distributed throughout several continents of the southern hemisphere, a fact that gave support to Alfred Wegener's early ideas regarding Continental drift theory. The type of cotton fibres used for making paper are discarded as unusable waste from the textile industry, and can be manufactured using fewer chemicals and less energy. Fossil forests of petrified wood have been found in all continents. Their reasons for doing this are that the cotton based tissue papers are less abrasive, less likely to cause allergic reactions, and far more environmentally friendly than wood papers, as they are made from renewable materials. Such specimens may be cut and polished using lapidary equipment. However, at least one company (Cloudy Bay Cotton) has recently tried to introduce cotton based tissue papers to westernised countries as an alternative to wood based ones. Petrified wood is often heavily silicified (the organic material replaced by silicon dioxide), and the impregnated tissue is often preserved in fine detail.

Paper made in the west since the industrial revolution has been almost exclusively wood based, except for a few specialized papers like those used in banknotes. Petrified wood is common in some parts of the world, and is most frequently found in arid or desert areas were it is more readily exposed by erosion. The majority of modern book publishers now use acid-free paper. Sequoia and its allies, magnolia, oak, and palms are often found. Documents written on more expensive rag paper were more stable. The fossilized remains of conifer and angiosperm roots, stems and branches may be locally abundant in lake and inshore sedimentary rocks from the Mesozoic and Caenozoic eras. Unfortunately, the original wood-based paper was more acidic and more prone to disintegrate over time, through processes known as slow fires. In the Fossil Forest at Victoria Park in Glasgow, Scotland, the stumps of Lepidodendron trees are found in their original growth positions.

The office worker or the white-collar worker was slowly born of this transformation, which can be considered as a part of the industrial revolution. The spoil heaps of coal mines are the best places to collect; coal itself is the remains of fossilised plants, though structural detail of the plant fossils is rarely visible in coal. Cheap wood based paper also meant that keeping personal diaries or writing letters ceased to be reserved to a privileged few. The Coal Measures are a major source of Palaeozoic plant fossils, with many groups of plants in existence at this time. With the gradual introduction of cheap paper, schoolbooks, fiction, non-fiction, and newspapers became slowly available to nearly all the members of an industrial society. This fern-like tree combined a woody trunk with the fronds of a fern, but produced no seeds. Before this era a book or a newspaper was a rare luxury object and illiteracy was the norm. The Devonian period also saw the evolution of what many believe to be the first modern tree, Archaeopteris.

Together with the invention of the practical fountain pen and the mass produced pencil of the same period, and in conjunction with the advent of the steam driven rotary printing press, wood based paper caused a major transformation of the 19th century economy and society in industrialized countries. Early fossils of these ancient plants show the individual cells within the plant tissue. Although older machines predated it, the Fourdrinier paper making machine became the basis for most modern papermaking. The remains of fossil plants are not as common as fossil animals, although plant fossils are locally abundant in many regions worldwide. Paper remained a luxury item 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. Pollen, spores and algae (dinoflagellates and acritarchs) are used for dating sedimentary rock sequences. According to this theory, Chinese culture was less developed than the West in ancient times because bamboo, while abundant, was a clumsier writing material than papyrus; Chinese culture advanced during the Han Dynasty and preceding centuries due to the invention of paper; and Europe advanced during the Renaissance due to the introduction of paper and the printing press. Fossil land plants are recorded in terrestrial, lacustrine, fluvial and nearshore marine sediments.

Some historians speculate that paper was the key element in global cultural advancement. Plant fossils include roots, wood, leaves, seeds, fruit, pollen, spores, phytoliths, and amber (the fossilized resin produced by some plants). The oldest known paper document in the West is the Missel of Silos from the 11th century. Some climbing species, such as kudzu, which do not need to produce thick supportive tissue, may grow up to 12.5 mm/h. They used hemp and linen rags as a source of fiber. Some mosses grow less than 0.001 mm/h, while most trees grow 0.025-0.250 mm/h. After further commercial trading and the defeat of the Chinese in the Battle of Talas, the invention spread to the Middle East, where it was adopted in India and subsequently in Italy in about the 13th century. The growth rate of plants is extremely variable.

The technology was first transferred to Korea in 600 and then imported to Japan by a Buddhist priest, Dam Jing (曇徴) from Goguryeo, around 610, where fibres (called bast) from the mulberry tree were used. In temperate and boreal climates, they generally lose their leaves during the winter; many tropical plants lose their leaves during the dry season. Instruction in the manufacturing process was required, and the Chinese were reluctant to share their secrets. Among the vascular plants, perennials include both evergreens that keep their leaves the entire year, and deciduous plants which lose their leaves for some part. It spread slowly outside of China; other East Asian cultures, even after seeing paper, could not figure out how to make it themselves. Other plants may be organized according to their seasonal growth pattern:. Other sources trace the invention of this type of papermaking to China in 150 BC. Simple plants like algae may have short life spans as individuals, but their populations are commonly seasonal.

The Chinese court official Cai Lun described the modern method of papermaking in AD 105; he was the first person to describe how to make paper from cotton rags. Plants rely on soil primarily for water (in quantitative terms), but also obtain nitrogen, phosphorus and other crucial nutrients. Indeed, most of the above materials were rare and costly. These sugars are then used as building blocks and form the main structural component of the plant. Silk was sometimes used, but was normally too expensive to consider. Through a process known as photosynthesis, plants use the energy in sunlight to convert carbon dioxide from the air into simple sugars. In China, documents were ordinarily written on bamboo, making them very heavy and awkward to transport. It is a common misconception that most of the solid material in a plant is taken from the soil, when in fact almost all of it is actually taken from the air.

Further north, parchment or vellum, made of processed sheepskin or calfskin, replaced papyrus, as the papyrus plant requires subtropical conditions to grow. A number of plants are used decoratively, including a variety of flowers. Papyrus was produced as early as 3000 BC in Egypt, and in ancient Greece and Rome. Some vascular plants, referred to as trees and shrubs, produce woody stems and are an important source of building material. The word paper comes from the ancient Egyptian writing material called papyrus, which was woven from papyrus plants. Other plants that are eaten include fruits, vegetables, herbs, and spices. The heat produced by these can easily dry the paper to less than 6% moisture. Much of human nutrition depends on cereals.

These dryer cans heat to temperatures above 200ºF and are used in long sequences of more than 40 cans. Animals and most other organisms are aerobic, relying on oxygen; those that do not are confined to relatively few, anaerobic environments. On the paper machine, the most common is the steam-heated can dryer. These processes also radically changed the composition of the Earth's atmosphere, which as a result contains a large proportion of oxygen. In more modern times, various forms of heated drying mechanisms are used. The photosynthesis and carbon fixation conducted by land plants and algae are the ultimate source of energy and organic material in nearly all habitats. In the earliest days of papermaking this was done by hanging the paper sheets like laundry. Therefore, fungus has a kingdom of its own.

Drying involves using air and or heat to remove water from the paper sheet. They are not related to any of the photosynthetic groups, but are close relatives of animals. When making paper by hand, a blotter sheet is used. Fruiting bodies, of which mushrooms are the most familiar, are actually only the reproductive structures of fungi. On a paper machine this is called a felt (not to be confused with the traditional felt). Most fungi are formed by microscopic tubes called hyphae, which may or may not be divided into cells but contain eukaryotic nuclei. Once the water is forced from the sheet, another absorbant material must be used to collect this water. Unlike embryophytes and algae, fungi are not photosynthetic, but are saprophytes: they obtain their food by breaking down and absorbing surrounding materials.

Pressing the sheet removes the water by force. They are not in general close relatives of the green plants, acquiring chloroplasts separately from ingested or symbiotic green and red algae. The methods of doing so vary between the different processes used to make paper, but the concepts remain the same. In contrast, most other algae have chloroplasts with three or four membranes. This is accomplished through pressing and drying. The same is true of the red algae, and the two groups are generally believed to have a common origin. After the paper web is produced, the water must be removed from it in order to create a usable product. The chloroplasts of green plants are surrounded by two membranes, suggesting they originated directly from endosymbiotic cyanobacteria.

Standard sheet sizes are prescribed by governing bodies such as the International Organization for Standardization (ISO). They undergo closed mitosis without centrioles, and typically have mitochondria with flat cristae. When dried, this continuous web may be cut into rectangular sheets by slicing the web vertically and horizontally to the desired size. With a few exceptions among the green algae, all such forms have cell walls containing cellulose and chloroplasts containing chlorophylls a and b, and store food in the form of starch. Most mass-produced paper is made using the continuous Fourdrinier process to form a reel or web of fibers in a thin sheet. The kingdom Plantae is now usually taken to mean this monophyletic group, as shown above. The paper may then be removed from the mould, wet or dry, and go on to further processing. The embryophytes developed from green algae; the two are collectively referred to as the green plants or Viridiplantae.

Pressure may be applied to help remove additional water. Now they are considered neither, but protists. In the mould process, a quantity of pulp is placed into a form, with a wire-mesh base, so that the fibers form a sheet on the mesh and excess water can drain away. Many can move about, and some have even lost their ability to photosynthesize; when first discovered, these were considered as both plants and animals. This moving web is pressed and dried into a continuous sheet of paper. These and other algal groups also include various single-celled creatures and forms that are simple collections of cells, without differentiated tissues. A watermark may be impressed into the paper at this stage of the process. The most conspicuous are the seaweeds, multicellular algae that often closely resemble terrestrial plants, but as stated above are not plants, found among the green, red, and brown algae.

This dilute slurry is drained through a fine-mesh moving screen to form a fibrous web. However, they are not classified within the kingdom plantae but in the kingdom protista instead. The pulp mixture is further diluted with water resulting in a very thin slurry. The algae comprise several different groups of organisms that produce energy through photosynthesis. For example, Kaolin (or calcium carbonate) is added to produce the glossy papers typically used for magazines. These differ in that the seed embryo is enclosed, so the pollen has to grow a tube to penetrate the protective seed coat; they are the predominant group of flora in most biomes today. Once the fibers have been extracted, they may also be bleached, dyed, or have additional ingredients added to alter the appearance of the final product. The angiosperms, comprising the flowering plants, were the last major group of plants to appear, emerging from within the gymnosperms during the Jurassic and diversifying rapidly during the Cretaceous.

These fibres have already been treated once, so instead they need a more gentle process to break the fibers apart while preserving their integrity. Four surviving groups remain widespread now, particularly the conifers, which are dominant trees in several biomes. Recycled fibres do not need to be pulped in the conventional sense. Early seed plants are referred to as gymnosperms (naked seeds), as the seed embryo is not enclosed in a protective structure at pollination, with the pollen landing directly on the embryo. Removing the lignin from wood chips also serves to break them apart into the fibers that compose pulp. Whereas other vascular plants, such as ferns, reproduce by means of spores and so need moisture to develop, some seed plants can survive and reproduce in extremely arid conditions. Pulp that is broken down chemically is known as "chemical pulp." The main purpose of a chemical pulping process is to break down the chemical structure of lignin and render it soluble in a liquid (most often water) so it may be washed from the remaining fibers. In these the gametophyte stage is completely reduced, and the sporophyte begins life inside an enclosure called a seed, which develops while on the parent plant, and with fertilisation by means of pollen grains.

However, because the lignin will cause this paper to yellow, mechanical pulp is most often used for newspapers and other non-permanent goods. The first primitive seed plants, Pteridosperms (seed ferns) and Cordaites, both groups now extinct, appeared in the late Devonian and diversified through the Carboniferous, with further evolution through the Permian and Triassic periods. Since the lignin is not removed from mechanical pulp, yields are relatively high, approximately 90-98%. In most the sporophyte acts as a separate individual, while the gametophyte remains small. Pulp that has been broken down mechanically is often known as "groundwood pulp." The mechanical process to break down wood chips into pulp requires no chemicals. These include a cuticle resistant to desiccation, and vascular tissues which transport water throughout the organism. If the lignin is retained in the pulp, the paper will yellow when exposed to air and light. They have a number of adaptations that allowed them to overcome the limitations of the bryophytes.

These processes are not needed when breaking down recycled fibers, as the lignin has already been removed from the source material. Vascular plants first appeared during the Silurian period, and by the Devonian had diversified and spread into many different land environments. This is done via a chemical process. The sporophyte is short-lived and remains dependent on its parent gametophyte. When natural materials are used to make paper, it is usually necessary to break down the lignin inside of the plant's cell walls. This involves an alternation between two generations: a haploid stage, called the gametophyte, and a diploid stage, called the sporophyte. The source of fiber is often natural (softwood or hardwood trees or other plants) or recycled, such as old corrugated boxes, newsprint, or mixed paper. Most species of bryophyte remain small throughout their life-cycle.

The material to be used for making paper is first converted into pulp, a concentrated mixture of fibers suspended in liquid. They can only survive where moisture is available for significant periods, although some species are desiccation tolerant. Whether done by hand or with a paper machine, the paper making process has three simple steps:. Bryophytes first appeared during the early Palaeozoic. . Plants are distinguished from green algae, from which they evolved, by having specialized reproductive organs protected by non-reproductive tissues. Though generally considered a flexible material, the edges of paper sheets can act as very thin, fine-toothed saws, leading to paper cuts. About three hundred plant species do not photosynthesize but are parasites on other species of photosynthetic plants.

A stack of 500 sheets of paper is called a ream. All of these plants have eukaryotic cells with cell walls composed of cellulose, and most obtain their energy through photosynthesis, using light and carbon dioxide to synthesize food. However, other vegetable fiber materials including cotton, hemp, linen, and rice may be used. They also include a few of their close relatives, often called bryophytes, of which mosses and liverworts are the most common. The most common source of these fibers is wood pulp from pulpwood trees, (largely softwoods) such as spruce. They include the vascular plants, plants with full systems of leaves, stems, and roots. The fibers used are usually natural and composed of cellulose. Most familiar are the multicellular land plants, called embryophytes.

Paper was invented in Ancient China by a man named Ts'ai Lun in AD 105.Paper is a thin, flat material produced by the compression of fibers (or fibres). . paper machines- paper-engineering. Indeed, any attempt to match "plant" with a single taxon is doomed to fail, because plant is a vaguely defined concept unrelated to the presumed phylogenic concepts on which modern taxonomy is based. origami. However, these are still often considered plants in many contexts. papier-mâché. Since then, it has become clear that the Plantae as originally defined included several unrelated groups, and the fungi and several groups of algae were removed to new kingdoms.

For construction