Process of bleaching in textile

General Inspection

Examining fabric to identify defects.

Newly made goods, which frequently show imperfections, are carefully inspected, and defects are usually repaired by hand operations. The first inspection of woollen and worsted fabrics is called perching. Burling, mainly applied to woollen, worsted, spun rayon, and cotton fabrics, is the process of removing any remaining foreign matter, such as burrs and, also, any loose threads, knots, and undesired slubs. Mending, frequently necessary for woollens and worsteds, eliminates such defects as holes or tears, broken yarns, and missed warp or weft yarns.

Shearing

A process to remove surface irregularities in a fabric by passing it through a cylindrical machine with rotating spiral blades .i.e. the removal of protruding ends of threads, knots, and hairs from the surface of a fabric and the evening of the length of pile to improve the fabric’s appearance.

 Both woven and knitted fabrics undergo shearing. The process is carried out on two types of machines: lengthwise shearing machines (the major type) and transverse shearing machines, which are used to cut the fabric ends. The working element is a shearing mechanism consisting of a cylinder to which spiral blades are attached, a flat steel blade, a table, and guiding rollers. The rapidly rotating cylinder and the stationary flat blade form a scissors mechanism that cuts the fabric as it passes through the shearing mechanism.

Singeing

Singeing is a process applied to both yarns and fabrics to produce an even surface by burning off projecting fibres, yarn ends, and fuzz. This is accomplished by passing the fibre or yarn over a gas flame or heated copper plates at a speed sufficient to burn away the protruding material without scorching or burning the yarn or fabric

Also called gassing,. Singeing is usually followed by passing the treated material over a wet surface to assure that any smoldering is halted.

Desizing

 It is the process of removing the size material from the warp yarns after the textile fabric is woven.

Desizing, irrespective of what the desizing agent is, involves impregnation of the fabric with the desizing agent, allowing the desizing agent to degrade or solubilise the size material, and finally to wash out the degradation products.

Scouring

Scouring removes substances that have adhered to the fibres during production of the yarn or fabric, such as dirt, oils, and any sizing or lint applied to warp yarns to facilitate weaving.

Washing

Removes from the Cloth the chemicals used in previous process .i.e. Scouring ,bleaching etc..

Bleaching

Bleaching, a process of whitening fabric by removal of natural colour, such as the tan of linen, is usually carried out by means of chemicals selected according to the chemical composition of the fibre.

 Chemical bleaching is usually accomplished by oxidation, destroying colour by the application of oxygen, or by reduction, removing colour by hydrogenation. Cotton and other cellulosic fibres are usually treated with heated alkaline hydrogen peroxide; wool and other animal fibres are subjected to such acidic reducing agents as gaseous sulfur dioxide or to such mildly alkaline oxidizing agents as hydrogen peroxide. Synthetic fibres, when they require bleaching, may be treated with either oxidizing or reducing agents, depending upon their chemical composition. Cottons are frequently scoured and bleached by a continuous system.

Drying

Water, used in various phases of textile processing, accumulates in fabrics, and the excess moisture must eventually be removed. Because evaporative heating is costly, the first stage of drying uses mechanical methods to remove as much moisture as possible. Such methods include the use of centrifuges and a continuous method employing vacuum suction rolls. Any remaining moisture is then removed by evaporation in heated dryers. Various types of dryers operate by conveying the relaxed fabric through the chamber while festooned in loops, using a frame to hold the selvages taut while the fabric travels through the chamber, and passing the fabric over a series of hot cylinders. Because overdrying may produce a harsh hand, temperature, humidity, and drying time require careful control.

Mercerization

Mercerization is a process applied to cotton and sometimes to cotton blends to increase lustre (thus also enhancing appearance), to improve strength, and to improve their affinity for dyes. The process, which may be applied at the yarn or fabric stage, involves immersion under tension in a caustic soda (sodium hydroxide) solution, which is later neutralized in acid. The treatment produces permanent swelling of the fibre.

Calendering

Calendering is a final process in which heat and pressure are applied to a fabric by passing it between heated rollers, imparting a flat, glossy, smooth surface. Lustre increases when the degree of heat and pressure is increased. Calendering is applied to fabrics in which a smooth, flat surface is desirable, such as most cottons, many linens and silks, and various man-made fabrics. In such fabrics as velveteen, a flat surface is not desirable, and the cloth is steamed while in tension, without pressing. When applied to wool, the process is called pressing and employs heavy heated metal plates to steam and press the fabric. Calendering is not usually a permanent process.

FINISHING

Finishing refers to the processes that convert the woven or knitted cloth into a usable material and more specifically to any process performed after dyeing the yarn or fabric to improve the look, performance, or "hand" (feel) of the finished textile or cloth .

Alternative project life cycle and its different approaches

Projects have different time spans, depending on size and content . it is  important to recognize that not all projects  follow the same phases(may be less structured or simultaneous); which depends on nature  and requirements.

Projects approaches:

Depending on phases of project, it has  different methods or approaches to meet requirements or objectives. Such as

Functional decomposition:

In this process, first desired situation is defined then required components are determined to achieve objectives.. These components are analyze till all the requirements meets.

Gap analysis:

A process, in which current process is analyze  with desired situation  to highlight gaps.

Reverse engineering:

It is going back from existing product or process to its functional design, to know, how it works and how to improve.

Perpetual Bonds:

A bond which have no maturity(Issue for unlimited period of time) or in simple a perpetuity in the form of bonds .We can find intrinsic value of perpetual bond by formula mentioned below

There are two characteristic

1)      No Maturity

2)      Coupon rate

Intrinsic value = V = I/r

Where I stand for amount of interest or expected income on bond.

I = Par value of bond * Coupon rate

Example of Perpetual bond:

The British CONSOL is the example of perpetual bond.

Why project is unique from day to day business

Project is an undertaking, though which targeted goals are achieved, within defined resources like time , money and personnel etc.

For example, Usman has  recently received a new assignment, in which he will lead a team, who is going  to launch new product within next six month. Usman has  target ahead with limited time,  money and human resource etc.

Project management is application of knowledge, skills and techniques to get the project done effectively and efficiently.

Why project is unique from business:

-Time period: You will see, project mostly starts with specified and  fixed-time span.

-Schedule: It has plans over time for resources .

-Change: After the project completion, team carries forward for its next targeted projects.

-Uniqueness: It may never have been undertaken before and each project is different from other in some aspect.

Salt is a silent killer

There is no doubt, if we will say that salt has become a synonym for taste. But at the same time, it is also an emperor of diseases. Salt is used very commonly in our foods, but excessive use salt can lead us to many health hazards. Did we ever think, how much of salt, we need to consume per day? And what are disorders by excessive use?

Adults should consume only 2400 mg of Na(Sodium),equal to 2.4 grams of NaCl (Table Salt). Salt is a major factor for high blood pressure, paralysis, heart attack, arthritis, obesity, renal problems, asthma, allergy, sinus, swelling and diabetes etc.

Asthma. Due to excess salt, body lacks pure water, which leads to dehydration. A hormone called ‘Histamine’ is produced in such a situation; causes barrier while inhaling or breathing. Sticky substances are produced in lungs and cause sneeze, cold and allergy etc.

Swelling. Who takes more salt generally carry 6-7 litres of water, which causes body to swell, because excess water in body obstruct free flow of oxygen to the cells.

Diabetes. By using dietary salt, which has excessive presence of Potassium; which is an obstacle to  proper working of insulin.

Obesity. By eating more salt, you are allowing water to get stored in body, so your weight increases.

Paralysis. Paralysis basically occurs when the blood pressure shoots up and blood vessels narrow down, which would also cause by excess salt

Heart attack. When you consume too much sodium, thus your blood pressure boosts up, as time passes, vessels become harden, so fat deposition occur called plaque. It causes hardening of the arteries.

Reference > BM Insider 

Relationship Between Epilepsy And Sleep

This relationship was first studied in the nineteenth century. The interface between epilepsy and sleep medicine is rising, so there comes a new area to be attended by the specialists of sleep disorders and epidemiologists. The knowledge of these different mechanisms might be valuable for neurologists in order to discover new strategies for treatment.

According to Valente and Pentagna (2014), poor sleep conditions hygiene and primary sleep disorders should be addressed properly by epidemiologists. However, psychiatric disorders and cognitive deficiencies are addressed frequently to improve social functioning and quality of life of the patient. Epilepsy influences sleep by different mechanisms; however, sleep disorders may not be diagnosed properly in patients with epilepsy. As, epileptic patients have bad sleep quality because of the effects of antiepileptic medications and accompanying diseases like obstructive sleep apnea and insomnia. So, in this situation, a suitable treatment of epilepsy might be essential for a better sleep quality.

Sleep disorders and sleep fragmentation are considered as some of the factors that influence the worsening of seizure. According to them, seizure control can be improved by improving sleep quality. Therefore, treatment of sleep disorders and improved sleep hygiene may improve seizure control and quality of life. Treating beyond seizures has become a hallmark of the new approach of epilepsy. Moreover, they suggested that knowledge about epileptiform discharge behavior during sleep can be useful in clinical practice.

Reference BM Insider