The chromophore (the chemical group of a dye responsible for colour) of reactive dyes contain substituents that react with the substrate to which it is applied. Reactive dyes have better fastness properties owing to this covalent bonding, and are the most important method for coloring cellulose fibers but can also be used on wool and nylon. [1]
Reactive dye printing is a method of printing fabrics using reactive dye incorporated into a paste or wax including components such as sodium alginate gum, soda ash, urea and kerosin. Typically, the dye is dried at 130 degrees and cured at 180 degrees to permanently bond it, and the fabric later treated with a softener for better hand feel. [2]
A dye is a colored substance that chemically bonds to the material 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.
Screen printing is a printing technique where a mesh is used to transfer ink onto a substrate, except in areas made impermeable to the ink by a blocking stencil. A blade or squeegee is moved across the screen in a "flood stroke" to fill the open mesh apertures with ink, and a reverse stroke then causes the screen to touch the substrate momentarily along a line of contact. This causes the ink to wet the substrate and be pulled out of the mesh apertures as the screen springs back after the blade has passed. One colour is printed at a time, so several screens can be used to produce a multi-coloured image or design.
Dye-sublimation printing is a term that covers several distinct digital computer printing techniques that involve using heat to transfer dye onto a substrate.
Tie-dye is a term used to describe a number of resist dyeing techniques and the resulting dyed products of these processes. The process of tie-dye typically consists of folding, twisting, pleating, or crumpling fabric or a garment, before binding with string or rubber bands, followed by the application of dye or dyes. The manipulations of the fabric before the application of dye are called resists, as they partially or completely prevent ('resist') the applied dye from coloring the fabric. More sophisticated tie-dye may involve additional steps, including an initial application of dye before the resist, multiple sequential dyeing and resist steps, and the use of other types of resists and discharge.
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 the 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.
In a reactive dye, a chromophore contains a substituent that reacts with the substrate. Reactive dyes have good fastness properties owing to the covalent bonding that occurs during dyeing. Reactive dyeing is the most important method for coloring cellulose fibers. Reactive dyes can also be applied on wool and nylon; in the latter case they are applied under weakly acidic conditions. Reactive dyes have a low utilization degree compared to other types of dyestuff, since the functional group also bonds to water, creating hydrolysis.
Vat dyes are a class of dyes that are classified as such because of the method by which they are applied. Vat dyeing is a process that refers to dyeing that takes place in a bucket or vat. The original vat dye is indigo, once obtained only from plants but now often produced synthetically.
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.
Resist dyeing (resist-dyeing) is a traditional method of dyeing textiles with patterns. Methods are used to "resist" or prevent the dye from reaching all the cloth, thereby creating a pattern and ground. The most common forms use wax, some type of paste made from starch or mud, or a mechanical resist that manipulates the cloth such as tying or stitching. Another form of resist involves using a dye containing a chemical agent that will repel another type of dye printed over the top. The best-known varieties today include tie-dye, batik, and ikat.
The textile bleaching is one of the steps in the textile manufacturing process. The objective of bleaching is to remove the natural color for the following steps such as dyeing or printing or to achieve full white. All raw textile materials, when they are in natural form, are known as 'greige' material. They have their natural color, odor and impurities that are not suited to clothing materials. Not only the natural impurities will remain in the greige material, but also the add-ons that were made during its cultivation, growth and manufacture in the form of pesticides, fungicides, worm killers, sizes, lubricants, etc. The removal of these natural coloring matters and add-ons during the previous state of manufacturing is called scouring and bleaching.
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.
Lightfastness is a property of a colourant such as dye or pigment that describes its resistance to fading when exposed to light. Dyes and pigments are used for example for dyeing of fabrics, plastics or other materials and manufacturing paints or printing inks.
Colour fastness is a term—used in the dyeing of textile materials—that characterizes a material's colour's resistance to fading or running. Colour fastness is the property of dyes and it is directly proportional to the binding force between photochromic dye and the fibre. The colour fastness may also be affected by processing techniques and choice of chemicals and auxiliaries.
Wet Processing Engineering is one of the major streams in Textile Engineering or Textile manufacturing 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.
Lumi, Inc. is a Los Angeles–based company founded by Jesse Genet and Steph Ango that offers packaging and supply chain management software. The company got its start developing Inkodye, a photo-reactive vat dye that develops its color through exposure to UV or sunlight. The company was acquired by Narvar in 2021.
Yūzen (友禅) is a Japanese resist dyeing technique where dyes are applied inside outlines of dyed or undyed rice-paste resist, which may be drawn freehand or stencilled; the paste keeps the dye areas separated. Originating in the 17th century, the technique became popular as both a way of subverting sumptuary laws on dress fabrics, and also as a way to quickly produce kimono that appeared to be painted freehand with dyes. The technique was named after Miyazaki Yūzen (宮崎友禅), a 17th century fan painter who perfected the technique. Miyazaki Yūzen's fan designs became so popular that a book called the yūzen-hiinagata was published in 1688, showing similar patterns applied to kosode. A fashion for elaborate pictorial yūzen designs lasted until 1692.
Cold pad batch (CPB) is a method of dyeing textiles, typically cellulosic fibers such as cotton, in which the textile is impregnated with dye in a cold state, rather than being heated. High dye fixation and no thermal energy are the advantages of the CPB process. CPB-dyed fabrics are less expensive, have a softer hand feel, and have a cleaner surface than exhaust dyed materials. The process may take up to 12 hours in the batching process, depending on the depth of the shade. The disadvantage is that batching is a time-consuming and lengthy process. The process was developed in 1960.
Discharge printing is a textile printing technique that involves the application of a discharging agent to strip dye from already-dyed cloth in order to produce a printed pattern, which can be either white or colored. It is a method to imprint a design onto dyed fabric. The print pattern is achieved by applying a substance capable of removing the color, such as chlorine or hydrosulfite, to create a white or light pattern on a darker-hued dyed background. A dischargeable dye is employed for dischargeable printing.
In textile processing, stripping is a color removal technique employed to partially or eliminate color from dyed textile materials. Textile dyeing industries often face challenges like uneven or flawed dyeing and the appearance of color patches on the fabric's surface during the dyeing process and subsequent textile material processing stages. Stripping is one of the reprocessing methods used to correct undesirable colors and flaws in dyed materials. The efficacy of this process relies on factors such as the dye type, fiber material, and the stripping agents utilized. Additionally, the procedure is recognized by alternative terms, namely back stripping or destructive stripping.
{{cite web}}
: Missing or empty |title=
(help)