তোশক
তোশক হল এক প্রকার বড় প্যাড যা শায়িত দেহের ভার বহন করে এবং বিছানা এর অংশ হিসেবে ব্যবহৃত হয়।তোশক সাধারণত গদি দ্বারা তৈরি করা হয় বা মোটা নরম কাপড়,চুল,তুলা,ফোম কিংবা কাঠামো ভিত্তিক লোহার স্প্রিং দ্বারা তৈরি করা হয়। কিছু তোশক আবার বায়ু বা পানি দ্বারা ভর্তি করে তৈরি করা হয়।
তোশক শব্দটি বাংলায় ফরাসি শব্দ থেকে আগত। 
তোশক এর ইংরেজি প্রতিশব্দ "mattress, আরবি শব্দ "matrah" থেকে এসেছে যার অর্থ "নিচে ফেলানো কিছু" বা "সেই জায়গা যেখানে কিছু ফেলানো হয়"।ক্রুসেড এর সময় ইউরোপিয়ানরা আরবীয়দের মেঝেতে জাজিম পেতে শোয়ার পদ্ধতি আয়ত্ত্ব করে।
তোশক শক্ত কাঠামো বিশিষ্ট বিছানা এর ওপর পাতা হয়, বিছানা এর ভিত্তি হিসেবে বা একটি মোটা কাঠ অথবা বাক্স বসানো ভিত্তির সাথে উভয় মোটা গদি হিসেবে এবং একক ভিত্তি ইউনিট হিসেবে ব্যবহৃত হয়। ডিভানদের অন্তত একটি স্প্রিংযুক্ত স্তর থাকে যার সাথে অন্যান্য তোশক তৈরির সরঞ্জামাদিও থাকে। সেটা সেকেন্ডারি তোশক হিসেবে বা সরণশীল উপরের স্তর হিসেবে সরবরাহ করা হতে পারে।
প্রাথমিক তোশকগুলো তৈরি হতো খড়, পালক বা ঘোড়ার চুল সহ বিভিন্ন প্রকার প্রাকৃতিক উপাদান দ্বারা।বিশ শতক এর প্রথমার্ধে, উত্তর আমেরিকা কর্তৃক বিক্রিত একটি তোশকের স্প্রিং এর মজ্জার সাথে তুলার ব্যাটিং বা আঁশ ভর্তি ছিল।আধুনিক তোশক গুলোতে সাধারণত অন্তঃস্প্রিং ভিত্তি কিংবা ল্যাটেক্স, ভিসকোয়েলাস্টিক বা অন্যান্য নমনীয় পলিইউরেথিন ফোম থাকে।অন্যান্য ভর্তির সামগ্রীর মধ্যে কুণ্ডলীর ওপর বসানো অন্তরক প্যাড রয়েছে যা বিছানা এর সজ্জার স্তর গুলোকে অন্তঃস্প্রিং এর সংস্পর্শে আসা থেকে রোধ করে, সাথে সাথে বিছানা এর উপরের সজ্জার স্তরে একটি পলেস্টারের নরম আবরণ তৈরি করে।১৮৯৯ সালে জেমস মার্শাল প্রথম স্বতন্ত্রভাবে মোড়ানো স্প্রিং এর কুণ্ডলীযুক্ত তোশক পরিচিত করান যা সাধারন ভাবে মার্শাল কয়েলস্ নামে পরিচিত।তোশক পানি কিংবা বায়ু দ্বারা বা বিভিন্ন প্রকার প্রাকৃতিক আঁশ যেমন ফুটোন দ্বারাও ভর্তি করা হয়।দক্ষিণ-পূর্ব এশিয়াতে কাপোক এবং দক্ষিন এশিয়াতে কোইর হল তোশক তৈরির সাধারণ উপাদান।
বর্তমানে উত্তর আমেরিকায় বহুল বিক্রিত তোশক স্প্রিং এর মজ্জা যুক্ত ; তবে সম্পূর্ণ ফোম যুক্ত বিছানা এবং হাইব্রিড বিছানা, যাদের আরামদায়ক স্তরের মধ্যে স্প্রিং মজ্জা এবং ভিস্কো-ইলাস্টিক বা ল্যাটেক্স এর মতো উচ্চ মানের ফোম উভয়ই অন্তর্ভুক্ত থাকে, সেসব তোশকের ওপর লোকের আগ্রহ বৃদ্ধি পাচ্ছে। ইউরোপে পলিইউরেথিন ফোমের মজ্জা এবং ল্যাটেক্স এর মজ্জা খুবই জনপ্রিয় এবং বিক্রিত তোশকের একটি উল্লেখযোগ্য অংশ।
প্রচলিত তোশক দুটি প্রাথমিক অংশ নিয়ে গঠিত– একটি "কেন্দ্র" বা "সমর্থন স্তর" এবং "শয়ন স্তর" বা "আরামদায়ক স্তর"। এই দুটি অংশকে একসাথে একটি মোটা বস্ত্রে মোড়া হয়। একে বলা হয় "[[ticking]]."
শয়ন স্তরগুলো সমর্থন স্তুরগুলোকে ঢেকে রাখে এবং আরাম প্রদান করে। শয়ন স্তরটি তিনটি অংশ দ্বারা গঠিত। যথা - ইন্সুলেটর, মধ্য শয্যা এবং কুইল্ট।
তোশক সাধারণত বানানো হয় বেড সাইজিং স্ট্যান্ডার্ডস এর সাথে মিল রাখার জন্য যা বাজারের ভিন্নতায় বিভিন্নরকম হয়ে থাকে।
Innerspring mattresses commonly consist of just the spring core, and the top and bottom upholstery layers.
The core of the mattress supports the sleeper’s body. Modern spring mattress cores, often called "innersprings," are made up of steel [[coil spring]]s, or "coils."
The [[American wire gauge|gauge]] of the coils is another factor which determines firmness and support. Coils are measured in quarter increments. The lower the number, the thicker the spring. In general, higher-quality mattress coils have a 14-gauge (1.63 mm) diameter. Coils of 14 to 15.5-gauge (1.63 to 1.37 mm) give more easily under pressure, while a 12.5-gauge (1.94 mm) coil, the thickest typically available, feels quite firm.
Connections between the coils help the mattress retain its shape. Most coils are connected by interconnecting wires; encased coils are not connected, but the fabric encasement helps preserve the mattress shape.
There are four types of [[mattress coil]]s:
Upholstery layers cover the mattress and provide cushioning and comfort. Some manufacturers call the mattress core the "support layer" and the upholstery layer the "comfort layer." The upholstery layer consists of three parts: the insulator, the middle upholstery, and the quilt.
The insulator separates the mattress core from the middle upholstery. It is usually made of fibre or mesh and is intended to keep the middle upholstery in place.
The middle upholstery comprises all the material between the insulator and the quilt. It is usually made from materials which are intended to provide comfort to the sleeper, including flexible polyurethane foam (which includes convoluted "egg-crate" foam), visco-elastic foam, latex foam, felt, polyester fiber, cotton fiber, wool fiber and nonwoven fiber pads. In Europe and North America, mattress makers have begun incorporating gel-infused foams, soft-solid gels layered over foam, and poured gels in the top comfort layer of the bed.
The quilt is the top layer of the mattress. Made of light foam or fibres stitched to the underside of the ticking, it provides a soft surface texture to the mattress and can be found in varying degrees of firmness.
There are three main types of foundation or [[bed base]]:
Typically the measurements of a foundation will be about 1-2" shorter than the measurement of a mattress.
[[Ticking]] is the protective fabric cover used to encase mattresses and foundations. It is usually designed to coordinate with the foundation border fabric and comes in a wide variety of colors and styles. Mattress fabrics can be knits, damask or printed wovens, or inexpensive nonwovens. During the past decade, along with the rise in popularity of all-foam beds, stretchy knit ticking on the bed's top panel has become a standard look on both innerspring and foam beds. Most ticking is made with polyester yarns. More expensive mattress fabrics may contain a combination of polyester with rayon, cotton, silk, wool or other natural yarns.
Until the early 2000s, beds were normally upholstered with a single fabric. This was usually a damask ticking or, for inexpensive bedsets, a nonwoven fabric covering all surfaces of the mattress and foundation. Today's bedsets are covered with up to six different fabrics: A better quality circular knit or woven damask on the top panel—the bed's sleeping surface; a matching or contrasting [usually woven] fabric on the border of the mattress; a matching or contrasting [usually woven] fabric on the foundation side panels; a 'non-skid' woven or non-woven fabric on the surface of the foundation and reverse side of the mattress; and a nonwoven dust cover on the under side of the foundation. Some North American mattress producers are beginning to use furniture upholstery fabrics on the bed's borders giving beds a more European, home furnishings look.
All-foam mattresses use different weights and densities of petrochemical-based flexible polyurethane foams and visco-elastic foams or memory foam, and [[latex rubber]] foams. A number of mattress manufacturers have incorporated polyurethane and visco-elastic foams with a portion of plant-based content. All-foam mattresses are often paired with [[platform bed|platform base]]s.
Latex foam in mattresses is generally a blend of the latex of the [[Hevea brasiliensis]] tree and synthetic latex, which is derived from petrochemicals and other substances and fillers. There are, however, natural latex mattresses that leave out polyurethane-based chemicals. Latex foam is produced using either the [[Talalay Process|Talalay]] or the [[Dunlop Rubber|Dunlop]] process. Each provides a different feel. Dunlop is generally a firmer foam, Talalay is softer. While the Dunlop process produces a denser foam, the Talalay process produces a lighter one that has more air in it. If you were to weigh each as latex cores, the Dunlop foam would be heavier because it has more latex in it. Talalay is more expensive as its production is more resource intensive. Natural latex foam has a higher latex content than synthetic latex, however, "100% natural latex foam" is misleading.
[[Memory foam]] mattresses use conforming visco-elastic foam over firmer polyurethane base foam. Some innerspring mattresses have memory foam in their upholstery layer. Different feels and comfort levels are achieved by varying the thickness, weight and formulation of the visco-elastic foams and the base foams. Latex and memory foam mattresses each provide a unique feel. This type of mattress is good at relieving pressure on painful joints. Many memory foam mattresses are more expensive than standard spring mattresses.
Memory foam is affected by temperature. In a cool bedroom, a memory foam mattress will feel firmer than it does in a warm bedroom. Memory softens and conforms to the sleeper in response to body temperature and body weight. Traditional memory foam molds to the body creating a depression the sleeper must roll out of when changing sleep positions. Mattress manufacturers have responded to this issue by using "faster response" memory foams. They spring back more quickly when the sleeper moves. Foam mattresses are also known to generally "sleep warmer" than innerspring mattresses. Mattress makers have addressed the issue with "open-cell" memory foams, pinhole cored memory foam, gel-infused memory foams, channel-cut foam cores, reticulated foam support layers and other technologies to improve air circulation through all-foam beds.
Similar to memory foam mattresses, a high density foam mattress uses a more compact foam typically made from [[polyurethane]]. This kind of foam is made largely from open cells that are packed together tightly. High density foam mattresses offer comfort and longevity because they are more dense than a traditional foam mattress. High density foam mattresses that have an innerspring system last even longer and eliminate mattress sagging.
Mattresses can also be made from bladders of some fluid, notably water or air. These date to antiquity – goatskin bladders filled with water were used in Persia at least as early as 3600 BCE – and gained increased popularity in the 20th century with improved manufacturing.
Air mattresses use one or more air chambers instead of springs to provide support. Quality and price can range from inexpensive ones used occasionally for camping, to high-end luxury beds. Air mattresses designed for typical bedroom use cost about the same as inner-spring mattresses with comparable features. Air bladder construction varies from a simple polyethylene bag to internally baffled, multiple chambers of [[latex]] (vulcanized rubber) or [[vinyl]] with bonded cotton exteriors. Mattresses may have a layer of foam above the air chambers for added cushioning, and may be enclosed in a cover. Some such beds are termed soft-sided air beds.
Permanent use adjustable-firmness "airbeds" became popular particularly after market leader [[Select Comfort]] began a major marketing campaign around 2001. The original airbed was manufactured by Comfortaire in 1981, which was later purchased by Select Comfort. There are several other manufacturers. Some allow independent adjustment of each side of the bed. They are made in a variety of models from basic, no-frills ones that measure about 7" in height, to high-profile, 15" tall hybrids that contain several types of foam, pillow tops, and digital pumps with memory for individual pressure settings. Studies suggest that adjustable-firmness beds are better for back pain.
Adjustable-firmness mattresses for medical use have special control mechanisms. In the 1990s self-adjusting air beds that automatically change their pressure periodically, or inflate and deflate several air chambers alternately, were introduced. The intention of these periodic changes is to reduce problems with decubitus ulcers ([[Bedsore|bed sores]]), though the effectiveness of these techniques was still being researched.
Air mattresses for camping are available which are filled with foam which itself provides little support, but expands when the air valve is opened allowing air to enter, so the mattress (nearly) inflates by itself. This is especially useful for campers who carry their equipment as, unlike with normal air mattresses, no pump is needed for inflating. Available brands include Aerobed, Coleman, [[Therm-a-Rest]] and others.
The U.S. Consumer Product Safety Commission advises consumers not to let infants sleep on air mattresses. This is motivated by reports of deaths, mostly infants younger than 8 months of age, who were placed to sleep on air mattresses, and either suffocated in a face down position on an air mattress or died due to suffocation after falling into gaps between the mattress and bed frame, or the mattress and adjacent furniture or wall.
A waterbed is a mattress with water in its interior instead of metal coils or air. Waterbeds can be lined with different layers of fiber to achieve the level of firmness the user desires. Waterbeds are well known for providing support to the spine and other body parts, similar to the other mattress types. There are several options of support which range up to 100% waveless, where the user does not notice he/she is lying upon a waterbed.
[[বিষয়শ্রেণী:তোশক]]