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Mercerised Pulp
Mercerised pulp is a bleached pulp that is treated with hot diluted alkali to get extra high bulk and high porosity. The pulp feels and looks similar to a cotton ball. Manufacture Mercerising of pulp is a post treatment of fully bleached pulp normally of SBSK. The pulp is steeped in hot dilute caustic soda. The pulp fibres swell and the hydroxyl groups of the cellulose become crosslinked. The remaining hemicellulose is washed out and the pulp will subsequently not respond to refining. Applications * Filter paper * Non-wovens See also * Mercerised cotton Mercerisation is a textile finishing treatment for cellulose fabric and yarn, mainly cotton and flax, which improves dye uptake and tear strength, reduces fabric shrinkage, and imparts a silk-like luster. Development The process was devise ... References {{Paper Papermaking Cellulose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulp (paper)
Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops, waste paper, or rags. Mixed with water and other chemical or plant-based additives, pulp is the major raw material used in papermaking and the industrial production of other paper products. History Before the widely acknowledged invention of papermaking by Cai Lun in China around 105 AD, paper-like writing materials such as papyrus and amate were produced by ancient civilizations using plant materials which were largely unprocessed. Strips of bark or bast material were woven together, beaten into rough sheets, dried, and polished by hand. Pulp used in modern and traditional papermaking is distinguished by the process which produces a finer, more regular slurry of cellulose fibers which are pulled out of solution by a screen and dried to form sheets or rolls. The earliest paper produced in China consisted of bast fibers from the paper mulberr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cotton Ball
Cotton pads are pads made of cotton which are used for medical or cosmetic purposes. For medical purposes, cotton pads are used to stop or prevent bleeding from minor punctures such as injections or venipuncture. They may be secured in place with tape. Cotton pads are also used in the application and the removal of makeup. Cotton pads are soft enough that they can be used to clean babies. Cotton balls have much of the same applications as cotton pads, and can be used interchangeably . History Use of cotton for sanitary purposes likely dates back to its domestication. There is evidence that toilet paper, made in part of cotton and/or other plant fibers such as hemp, was used at least as early as 589 AD in China. Cotton balls have been used for applying gold leaf since at least as far back as 1801. An artists' manual from that year recommends using a "squirrel's tail, or cotton ball" to press the gold leaf into place. There is some evidence that they were being mass produced a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bleaching Of Wood Pulp
Bleaching of wood pulp is the chemical processing of wood pulp to lighten its color and whiten the pulp. The primary product of wood pulp is paper, for which whiteness (similar to, but distinct from brightness) is an important characteristic. These processes and chemistry are also applicable to the bleaching of non-wood pulps, such as those made from bamboo or kenaf. Paper brightness Brightness is the amount of incident light reflected from paper under specified conditions, usually reported as the percentage of light reflected, so a higher number means a brighter or whiter paper. In the US, the TAPPI T 452 or T 525 standards are used. The international community uses ISO standards. The table shows how the two systems rate high-brightness papers, but there is no simple way to convert between the two systems because the test methods are so different. The ISO rating is higher and can be over 100. This is because contemporary white paper incorporates fluorescent whitening ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SBSK (pulp)
Southern bleached softwood kraft (SBSK) is a wood pulp mainly produced in the southern USA. The main raw materials are slash pine, longleaf pine, shortleaf pine, loblolly pine and virginia pine. Properties SBSK is produced from mixed fibre sources, but the main wood species of the pulp is dominating the properties. All have long fibres. Slash pine and longleaf pine have thick walled fibres and makes the pulp suitable for fluff pulp. Applications SBSK is used in fluff pulp, tissue paper, filter paper and mercerised pulp. It is used as reinforcement fibres when making paper or as raw material for kraft paper Kraft paper or kraft is paper or paperboard (cardboard) produced from chemical pulp produced in the kraft process. Sack kraft paper (or just sack paper) is a porous kraft paper with high elasticity and high tear resistance, designed for packag .... See also Northern bleached softwood kraft References Papermaking Pulp and paper industry {{Material-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caustic Soda
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates . The monohydrate crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, sodium hydroxide is frequently used alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students. Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxyl
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy groups. Both the negatively charged anion , called hydroxide, and the neutral radical , known as the hydroxyl radical, consist of an unbonded hydroxy group. According to IUPAC definitions, the term ''hydroxyl'' refers to the hydroxyl radical () only, while the functional group is called a ''hydroxy group''. Properties Water, alcohols, carboxylic acids, and many other hydroxy-containing compounds can be readily deprotonated due to a large difference between the electronegativity of oxygen (3.5) and that of hydrogen (2.1). Hydroxy-containing compounds engage in intermolecular hydrogen bonding increasing the electrostatic attraction between molecules and thus to higher boiling and melting points than found for compounds that lack this f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant organic polymer on Earth. The cellulose content of cotton fiber is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%. Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton. Some animals, particularly ruminants and termites, can digest cellulose with the help of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemicellulose
A hemicellulose (also known as polyose) is one of a number of heteropolymer, heteropolymers (matrix polysaccharides), such as arabinoxylans, present along with cellulose in almost all embryophyte, terrestrial plant cell walls.Scheller HV, Ulvskov Hemicelluloses.// Annu Rev Plant Biol. 2010;61:263-89. doi: 10.1146/annurev-arplant-042809-112315. Cellulose is crystalline, strong, and resistant to hydrolysis. Hemicelluloses are branched, shorter in length than cellulose, and also show a propensity to crystallize. They can be hydrolyzed by dilute acid or Base (chemistry), base as well as a myriad of Cellulase, hemicellulase enzymes. Composition Diverse kinds of hemicelluloses are known. Important examples include xylan, glucuronoxylan, arabinoxylan, glucomannan, and xyloglucan. Hemicelluloses are polysaccharides often associated with cellulose, but with distinct compositions and structures. Whereas cellulose is derived exclusively from glucose, hemicelluloses are composed of diverse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refining (papermaking)
Refining (also perhaps called by the mathematical term affining) is the process of purification of a (1) substance or a (2) form. The term is usually used of a natural resource that is almost in a usable form, but which is more useful in its pure form. For instance, most types of natural petroleum will burn straight from the ground, but it will burn poorly and quickly clog an engine with residues and by-products. The term is broad, and may include more drastic transformations, such as the reduction of ore to metal (for which see Refining (metallurgy)). The refining of liquids is often accomplished by distillation or fractionation; this process is useful, for example, for isolating different fractions of petroleum. Gases can be refined in this way as well, by being cooled and/or compressed until they liquefy. Gases and liquids can also be refined by extraction with a selective solvent that dissolves away either the substance of interest, or the unwanted impurities. Many solids c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filter Paper
Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine solid particles from liquids or gases. The raw materials are different paper pulps. The pulp may be made from softwood, hardwood, fiber crops, mineral fibers. Properties Filter paper has various properties. The important parameters are wet strength, porosity, particle retention, volumetric flow rate, compatibility, efficiency and capacity. There are two mechanisms of filtration with paper; volume, and surface. By volume filtration, the particles are caught in the bulk of the filter paper. By surface filtration, the particles are caught on the paper surface. Filter paper is mostly used because of the ability of a small piece of filter paper to absorb a significant volume of liquid. Manufacture The raw materials are different paper pulps. The pulp may be from softwood, hardwood, fiber crops, mineral fibers. For high quality filters, dissolving pulp and merc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-wovens
Nonwoven fabric is a fabric-like material made from staple fibre (short) and long fibres (continuous long), bonded together by chemical, mechanical, heat or solvent treatment. The term is used in the textile manufacturing industry to denote fabrics, such as felt, which are neither woven nor knitted. Some non-woven materials lack sufficient strength unless densified or reinforced by a backing. In recent years, non-wovens have become an alternative to polyurethane foam. Applications Nonwoven fabrics are broadly defined as sheet or web structures bonded together by entangling fiber or filaments (and by perforating films) mechanically, thermally or chemically. They are flat or tufted porous sheets that are made directly from separate fibres, molten plastic or plastic film. They are not made by weaving or knitting and do not require converting the fibres to yarn. Typically, a certain percentage of recycled fabrics and oil-based materials are used in nonwoven fabrics. The percentag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercerised Cotton
Mercerisation is a textile finishing treatment for cellulose fabric and yarn, mainly cotton and flax, which improves dye uptake and tear strength, reduces fabric shrinkage, and imparts a silk-like luster. Development The process was devised in 1844 by John Mercer, who treated cotton with solutions of20–30% sodium hydroxide followed by washing. Mercer observed that the treatment shrank the fabric and increased its tensile strength and affinity for dyes. In the original process of Mercer, no tension was applied. The product was termed ''fulled cotton'', a nod to the process of fulling in woven wool fabric. Mercer regarded the increased affinity for dyes as the most important technical aspect. Mercer also experimented with sulfuric acid and zinc chloride solutions and discovered the parchmentising effect of sulfuric acid. The silk-like lustre now commonly associated with mercerising is produced by tension and was discovered by Horace Lowe in 1889. Process Treatment wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
