Ageing (Stoving, Hanging, [1] or Aging [2] [3] ) is a kind of after treatment process for certain printed textile materials in which the goods are exposed to warm and moist atmosphere. Steaming is an evolved way to obtain the intended results. The objectives of the ageing process include the developing and fixing of the mordants and colors. [4]
The process is carried out using a variety of machines, including "loop agers." Fabric hangs and runs over guide rollers as it is exposed to steam at a certain temperature and for a specific amount of time. [1] [5] [2]
Initially, colours were fixed through the action of sunlight, air, and dew, which evolved into ageing rooms and, more recently, rapid-aging systems (in the form of steam-cabinets). [6]
Stoving was the early name used to describe the process of ageing in wooden or brick chambers heated by a furnace beneath. In stoving, temperature or heating was the consideration, while it ignored moisture application. When block printed material (one of the earliest forms of printing textiles) containing iron or aluminium mordants was thought to require merely heat to adhere to fabric, it was used. Those chambers were named "stoves." Stoving was first used to dry and age printed items, taking into account things like dye smearing and marking. Later, when it was found that steam and cold air without heat gave better results, stoving rooms were turned into ageing rooms. [4]
D. Koechlin was the first to emphasize the critical nature of carefully regulating the humidity level in ageing rooms. [7] [4]
The machine which reduced the ageing time from days to hours was introduced by Thom and Walter Crum. John Thom developed the first system that provided for the methodical introduction of moisture into the oxidation chamber. [7]
While the term "ageing" is more commonly associated with printed items, the process also implies the dyeing of Aniline black. [8] It is an treatment for printed materials that is done afterward to achieve better fixation and make them last longer. [4]
The primary objectives of ageing include the development and fixation of mordants and colors. [4] The following are some other areas where ageing has an effect.
The treatment takes place in a chamber supplied with saturated steam at atmospheric pressure. The required conditions are created in an ager machine fitted with controls that maintain a specified temperature on the fabric for a fixed time frame. With continual feeding, an ager can hold and release the cloth. A variety of ageing machines are used for this purpose. The names of the ageing machines include loop ager, festoon ager, cottage steamer, star steamer, and tower ager. Some machines are used for batch processing, while others are used for continuous processing; a loop ager is a continuous type of machine. [2] [9]
In some cases, loop ager is also employed in polyester dyeing. [10]
When acid vapours (from volatile acids) are used to conduct the action, this is referred to as acid ageing. [8]
Calico in German Nessel is a heavy plain-woven textile made from unbleached, and often not fully processed, cotton. It may also contain unseparated husk parts. The fabric is far coarser than muslin, but less coarse and thick than canvas or denim. However, it is still very cheap owing to its unfinished and undyed appearance.
A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution, and may require a mordant to improve the fastness of the dye on the fiber.
Dye-Sublimation Printing is a computer printing technique which uses heat to transfer dye onto materials such as a plastic, card, paper, or fabric. The sublimation name was first applied because the dye was considered to make the transition between the solid and gas states without going through a liquid stage. This understanding of the process was later shown to be incorrect, as there is some liquefying of the dye. Since then, the proper name for the process has become known as dye-diffusion, though this technically correct term has not supplanted the original name. Many consumer and professional dye-sublimation printers are designed and used for producing photographic prints, ID cards, clothing, and more.
A mordant or dye fixative is a substance used to set dyes on fabrics by forming a coordination complex with the dye, which then attaches to the fabric. It may be used for dyeing fabrics or for intensifying stains in cell or tissue preparations. Although mordants are still used, especially by small batch dyers, it has been largely displaced in industry by directs.
Dyeing is the application of dyes or pigments on textile materials such as fibers, yarns, and fabrics with the goal of achieving color with desired color fastness. Dyeing is normally done in a special solution containing dyes and particular chemical material. Dye molecules are fixed to the fiber by absorption, diffusion, or bonding with temperature and time being key controlling factors. The bond between dye molecule and fiber may be strong or weak, depending on the dye used. Dyeing and printing are different applications; in printing, color is applied to a localized area with desired patterns. In dyeing, it is applied to the entire textile.
Frederick Crace Calvert, English chemist, was born near London. He was the son of Alfred Crace and the nephew of the noted interior decorator, Frederick Crace.
Textile printing is the process of applying color to fabric in definite patterns or designs. In properly printed fabrics the colour is bonded with the fibre, so as to resist washing and friction. Textile printing is related to dyeing but in dyeing properly the whole fabric is uniformly covered with one colour, whereas in printing one or more colours are applied to it in certain parts only, and in sharply defined patterns.
Heat setting is a term used in the textile industry to describe a thermal process usually taking place in either a steam atmosphere or a dry heat environment. The effect of the process gives fibers, yarns or fabric dimensional stability and, very often, other desirable attributes like higher volume, wrinkle resistance or temperature resistance. Very often, heat setting is also used to improve attributes for subsequent processes.
The conservation and restoration of textiles refers to the processes by which textiles are cared for and maintained to be preserved from future damage. The field falls under the category of art conservation, heritage conservation as well as library preservation, depending on the type of collection. The concept of textile preservation applies to a wide range of artifacts, including tapestries, carpets, quilts, clothing, flags and curtains, as well as objects which "contain" textiles, such as upholstered furniture, dolls, and accessories such as fans, parasols, gloves and hats or bonnets. Many of these artifacts require specialized care, often by a professional conservator.
In textile manufacturing, 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 finish textile or clothing. The precise meaning depends on context.
Digital textile printing is described as any ink jet based method of printing colorants onto fabric. Most notably, digital textile printing is referred to when identifying either printing smaller designs onto garments and printing larger designs onto large format rolls of textile. The latter is a growing trend in visual communication, where advertisement and corporate branding is printed onto polyester media. Examples are: flags, banners, signs, retail graphics.
Rubia tinctorum, the rose madder or common madder or dyer's madder, is a herbaceous perennial plant species belonging to the bedstraw and coffee family Rubiaceae.
Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. The majority of natural dyes are vegetable dyes from plant sources—roots, berries, bark, leaves, and wood—and other biological sources such as fungi.
Dyeing is the craft of imparting colors to textiles in loose fiber, yarn, cloth or garment form by treatment with a dye. Archaeologists have found evidence of textile dyeing with natural dyes dating back to the Neolithic period. In China, dyeing with plants, barks and insects has been traced back more than 5,000 years. Natural insect dyes such as Tyrian purple and kermes and plant-based dyes such as woad, indigo and madder were important elements of the economies of Asia and Europe until the discovery of man-made synthetic dyes in the mid-19th century. Synthetic dyes quickly superseded natural dyes for the large-scale commercial textile production enabled by the industrial revolution, but natural dyes remained in use by traditional cultures around the world.
Wet process engineering is one of the major streams in textile engineering which refers to the engineering of textile chemical processes and associated applied science. The other three streams in textile engineering are yarn engineering, fabric engineering, and apparel engineering. The processes of this stream are involved or carried out in an aqueous stage. Hence, it is called a wet process which usually covers pre-treatment, dyeing, printing, and finishing.
Shweshwe is a printed dyed cotton fabric widely used for traditional Southern African clothing. Originally dyed indigo, the fabric is manufactured in a variety of colours and printing designs characterised by intricate geometric patterns. Due to its popularity, shweshwe has been described as the denim, or tartan, of South Africa.
Madurai Sungudi is Design of Madurai in the Indian state of Tamil Nadu, which is an exclusive textile product traditionally produced using tie and dye method by the Saurashtrians who migrated to Madurai under the patronage of King Thirumalai Naicker in the 17th century. The fabric's traditional popular use is as a saree; the fabric is now also used to make shirts, salwars, shawls, handbags, bed sheets and pillow cases. The product has been given protection under the GI registration act.
A stenter is a specialist oven used in the textile industry for drying and heat treating fabric after wet processing.
Batch dyeing is a method of dyeing a textile material. The method involves the gradual transfer of dye from a dye bath to the textile material in the same piece of equipment. The various methods of batch dyeing result from the type of machine used in the dyeing process. Common machinery used in the batch dyeing process include the jigger dyeing machine, winch dyeing machine, jet dyeing machine and beam dyeing machine.
Dunging was a process used in textile manufacturing to finish printed textiles, particularly those printed with aluminium or iron mordants.It was a process of exposing mordanted products into a solution of cow dung and hot water. Dunging was used to fix mordants as well as remove unfixed mordants and thickening agents from the fabric.