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Waterproof Paper
Waterproof paper uses special coatings (plastic-coated paper) and fibers to enhance durability, dimensional stability, tear resistance and resistance to changing shape or texture when exposed to water. The paper has applications for wet or damp environments, including outdoor, marine, field uses as well as printing applications for similar environments. The paper presents recycling challenges. Historically, waterproof paper was described in ''Scientific American'' in 1884. See also *Greaseproof paper *Liquid packaging board *Tyvek *Waterproofing *Wet strength The wet strength of paper and paperboard is a measure of how well the web of fibers holding the paper together can resist a force of rupture when the paper is wet. Wet strength is routinely expressed as the ratio of wet to dry tensile force at bre ... References Coated paper Paper {{Material-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coatings
A coating is a covering that is applied to the surface of an object, usually referred to as the substrate. The purpose of applying the coating may be decorative, functional, or both. Coatings may be applied as liquids, gases or solids e.g. Powder coatings. Paints and lacquers are coatings that mostly have dual uses of protecting the substrate and being decorative, although some artists paints are only for decoration, and the paint on large industrial pipes is for preventing corrosion and identification e.g. blue for process water, red for fire-fighting control etc. Functional coatings may be applied to change the surface properties of the substrate, such as adhesion, wettability, corrosion resistance, or wear resistance. In other cases, e.g. semiconductor device fabrication (where the substrate is a wafer), the coating adds a completely new property, such as a magnetic response or electrical conductivity, and forms an essential part of the finished product. A major consideratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastic-coated Paper
Plastic-coated paper is a coated or laminated composite material made of paper or paperboard with a plastic layer or treatment on a surface. This type of coated paper is most used in the food and drink packaging industry. Function The plastic is used to improve functions such as water resistance, tear strength, abrasion resistance, ability to be heat sealed, etc. Some papers are laminated by heat or adhesive to a plastic film to provide barrier properties in use. Other papers are coated with a melted plastic layer: curtain coating is one common method. Printed papers commonly have a top coat of a protective polymer to seal the print, provide scuff resistance, and sometimes gloss. Some coatings are processed by UV curing for stability. Components Most plastic coatings in the packaging industry are polyethylene (LDPE) and to a much lesser degree PET. Liquid packaging board cartons typically contain 74% paper, 22% plastic and 4% aluminum. Frozen food cartons are usually made u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiber
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, for example carbon fiber and ultra-high-molecular-weight polyethylene. Synthetic fibers can often be produced very cheaply and in large amounts compared to natural fibers, but for clothing natural fibers can give some benefits, such as comfort, over their synthetic counterparts. Natural fibers Natural fibers develop or occur in the fiber shape, and include those produced by plants, animals, and geological processes. They can be classified according to their origin: *Vegetable fibers are generally based on arrangements of cellulose, often with lignin: examples include cotton, hemp, jute, flax, abaca, piña, ramie, sisal, bagasse, and banana. Plant fibers are employed in the manufacture of paper and textile (cloth), and die ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paper Recycling
The recycling of paper is the process by which waste paper is turned into new paper products. It has a number of important benefits: It saves waste paper from occupying homes of people and producing methane as it breaks down. Because paper fibre contains carbon (originally absorbed by the tree from which it was produced), recycling keeps the carbon locked up for longer and out of the atmosphere. Around two-thirds of all paper products in the US are now recovered and recycled, although it does not all become new paper. After repeated processing the fibres become too short for the production of new paper, which is why virgin fibre (from sustainably farmed trees) is frequently added to the pulp recipe. There are three categories of paper that can be used as feedstocks for making ''recycled paper'': mill broke, pre-consumer waste, and post-consumer waste. ''Mill broke'' is paper trimmings and other paper scrap from the manufacture of paper, and is recycled in a paper mill. ''Pre-c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific American
''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many famous scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it. In print since 1845, it is the oldest continuously published magazine in the United States. ''Scientific American'' is owned by Springer Nature, which in turn is a subsidiary of Holtzbrinck Publishing Group. History ''Scientific American'' was founded by inventor and publisher Rufus Porter (painter), Rufus Porter in 1845 as a four-page weekly newspaper. The first issue of the large format newspaper was released August 28, 1845. Throughout its early years, much emphasis was placed on reports of what was going on at the United States Patent and Trademark Office, U.S. Patent Office. It also reported on a broad range of inventions including perpetual motion machines, an 1860 device for buoying vessels by Abraham Lincoln, and the universal joint which now can be found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greaseproof Paper
Greaseproof paper is paper that is impermeable to oil or grease, and is normally used in cooking or food packaging. It is usually produced by refining the paper stock and thus creating a sheet with very low porosity. This is then passed between hard pressure rollers ( supercalendered) to further increase the density, creating a paper called glassine. The glassine is treated with starches, alginates or carboxymethyl cellulose (CMC) in a size press to fill pores or treat the paper chemically to make it fat repellent. Basis weights are usually 30–50 g/m2. See also * Darcy (unit) * Parchment paper * Permeability (earth sciences) * Permeation * Wax paper Waxed paper (also wax paper, waxpaper, or paraffin paper) is paper that has been made moisture-proof and grease-proof through the application of wax. The practice of oiling parchment or paper in order to make it semi-translucent or moisture-pro ... References External links Greaseproof Board {{Paper Paper Food prepar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Packaging Board
Liquid packaging board is a multi-ply paperboard with high stiffness, strong wet sizing and a high barrier coating, e.g. plastic. Only virgin paper fibers are used. The barrier coating must hold the liquid and prevent migration of air and flavors through the paperboard. Manufacture A liquid packaging board might be up to five plies and is formed on a multi-ply paper machine with online coating. The most common is to use three plies with a basis weight of about 300 g/m2. The base or middle ply is normally made of pulp from bleached or unbleached chemical pulp, CTMP or ''broke'' (waste paper from a paper machine). CTMP gives more bulk and stiffness. The top ply (inside) is made of bleached chemical pulp. The barrier coating depends on the application and might be applied on both sides. When induction welding is employed an aluminum foil layer is used for barrier protection and for heating. The back side of the board is the printing side and might have an extra ply made from chemic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyvek
Tyvek () is a brand of synthetic flashspun high-density polyethylene fibers. The name "Tyvek" is a registered trademark of the American multinational chemical company DuPont, which discovered and commercialized Tyvek in the late 1950s and early 1960s. Tyvek's properties - such as being difficult to tear but easily cut, and waterproof against liquids whilst allowing water vapor to penetrate - have led to it being used in a variety of applications. Tyvek is often used as housewrap, a synthetic material used to protect buildings during construction, or as personal protective equipment (PPE). History Tyvek is a nonwoven product consisting of spun bond olefin fiber. It was first discovered in 1955 by a researcher for the DuPont textile company working in an experimental lab, who noticed a type of white fluff coming out of a pipe. That fluff was a form of polyethylene, which DuPont requested a patent for within a year of the discovery. After technologies improved during the next few ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waterproofing
Waterproofing is the process of making an object or structure waterproof or water-resistant so that it remains relatively unaffected by water or resisting the ingress of water under specified conditions. Such items may be used in wet environments or underwater to specified depths. ''Water-resistant'' and ''waterproof'' often refer to resistance to penetration of water in its liquid state and possibly under pressure, whereas '' damp proof'' refers to resistance to humidity or dampness. Permeation of water vapour through a material or structure is reported as a moisture vapor transmission rate (MVTR). The hulls of boats and ships were once waterproofed by applying tar or pitch. Modern items may be waterproofed by applying water-repellent coatings or by sealing seams with gaskets or o-rings. Waterproofing is used in reference to building structures (such as basements, decks, or wet areas), watercraft, canvas, clothing (raincoats or waders), electronic devices and paper packa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wet Strength
The wet strength of paper and paperboard is a measure of how well the web of fibers holding the paper together can resist a force of rupture when the paper is wet. Wet strength is routinely expressed as the ratio of wet to dry Tensile strength, tensile force at break. With combined board such as corrugated fiberboard or with laminations, wet strength also includes the ability to stay intact under humid or wet conditions. Wet strength adhesives are often needed. Mechanism The cellulose fibreweb of paper is mainly held together by hydrogen bonds. These are dependent on physical contact between the fibres and can be broken by wetting of the fibres. The residual strength of a wetted paper can be less than 10% of the original strength. Various techniques, such as refining of the pulp (paper), pulp and wet pressing on the paper machine can be used to reduce the strength loss of the paper upon wetting. To improve the wet strength it is common to use chemicals. The use of chemicals c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coated Paper
Coated paper (also known as enamel paper, gloss paper, and thin paper) is paper that has been coated by a mixture of materials or a polymer to impart certain qualities to the paper, including weight, surface gloss, smoothness, or reduced ink absorbency. Various materials, including kaolinite, calcium carbonate, bentonite, and talc, can be used to coat paper for high-quality printing used in the packaging industry and in magazines. The chalk or china clay is bound to the paper with synthetic s, such as styrene-butadiene latexes and natural organic binders such as starch. The coating formulation may also contain chemical additives as dispersants, resins, or polyethylene to give water resistance and wet strength to the paper, or to protect against ultraviolet radiation. Varieties Machine-finished coated paper ''Machine-finished coated paper'' (MFC) has a basis weight of 48–80 g/m2. They have good surface properties, high print gloss and adequate sheet stiffness. MFC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
