Silk Dyeing

Custom Fabric Dyeing is a process of finishing and dyeing textile. The concept of custom fabric dyeing can be methodical and rigorous. Custom Fabric Dyeing consists of evaluation of solids, textures, flannels, toweling, printed solids, printed textures and trims; checking color patterns in light box under three light sources and with X-Rite spectrophotometer; supervising quality in finish-dyeing departments. We at Ausilk generally provide customers best experience in solid dyed, yarn dyed and printed silk fabrics.

Among some of the natural fabric compositions that Custom Fabric Dyers treat are: cotton, linen, rayon, hemp, wool, viscose and silk. It is possible to dye blends of natural fabric and non-natural fabric (nylon, polyester, acetate); however, the colorfastness and color matching may not produce the expected result. Furthermore, the composition of non-natural fabric does not generally retain color well and may bleed and/or change color when washed.

Some of the industry-known fabric dyes include: Ciba, Clariant's Drimarene K, DyStar's Remazol and Levafix E. Such dyes ensure best colorfastness and permanent results even in hot water washing. If the fabric is made of wool it is generally best to dye it with Clariant's acid dyes, Sandolan MF and Nylosan N. For SILK fabircs, we at Ausilk widely use "CIBA" dyestuff, which proven to be the best dyes to get maximum result of color fastness.

Some garments experience shrinkage during the fabric dyeing process. Thorough preliminary analysis of the material is therefore required for the fabric to sustain a minimum amount of shrinkage. Performing analysis of garments on weight and shrinkage; correcting indices to suit appropriate methods of drying, fluffing and ironing; checking colorfastness to washing in hot and cold water; computer processing of color samples and lab testing are some of the methods required to achieve this minimum shrinkage. We at Ausilk normally conduct lab test with certified companies like SGS, MTL, ITS etc, upon request from customers, and provide test report for approval, prior to bulk sh ipment dispatch. For any fabric callout or limitations, we normally inform customers before taking the order to get understanding and acceptance of any possible "inperfection" of future test result, due to inherent or characteristic limits of the fabric.

Acid dye

An Acid dye is a dye in which the coloring component is in the anion. They are often applied from an acidic solution in order to intensify the staining. In the laboratory, the home or art studio, the acid used in the dyebath is often vinegar (acetic acid) or citric acid. The uptake rate of the dye is controlled with the use of sodium chloride.

In textiles, acid dyes are effective on protein fibers, i.e. animal hair fibers like wool, alpaca and mohair. They are also effective on silk. They are effective in dyeing the synthetic fiber nylon but of minimal interest in dyeing any other synthetic fibers.

In staining for microscopic examination for diagnosis or research acid dyes are used to color basic tissue proteins in contrast to basic dyes, which are used to stain cell nuclei and some other acidic components of tissues.

Acid dyes are generally divided into three classes which depend on fastness requirements, level dyeing properties and economy. The classes overlap and generally depend on type of fiber to be coloured and also the process used.

Acid dyes are thought to fix to fibers by hydrogen bonding, Van der Waals forces and ionic bonding. They are normally sold as the Sodium salt therefore they are in solution anionic. Animal protein fibers and synthetic Nylon fibers contain many cationic sites therefore there is an attraction of anionic dye molecule to a cationic site on the fiber. The strength (fastness) of this bond is related to the desire/ chemistry of the dye to remain dissolved in water over fixation to the fiber.

We at Ausilk normally use ACID dye for our silk fabrics. In some special and rare cases, we can also use reactive dyes for silk, while it is technically vey difficult to operate.

Reactive dye

In a reactive dye a chromophore contains a substituent that is activated and allowed to directly react to the surface of the substrate.Reactive dyes are used to dye cellulosic fibres. The dyes contain a reactive group, either a haloheterocycle or an activated double bond, that, when applied to a fibre in an alkaline dye bath, forms a chemical bond with an hydroxyl group on the cellulosic fibre.

Reactive dyeing is now the most important method for the coloration of cellulosic fibres. 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.

Dyestuffs with only one functional group sometimes have a low degree of fixation. To overcome this dyestuffs containing two different reactive groups (i.e. one monochlorotriazin and one vinyl sulfone) were created.

Dyestuffs containing two groups are also known as bifunctional dyestuffs, though some still refers to the original combination. Other types of bifunctional dyes has been introduced. The first bifunctional dye made where more tolerant to temperature deviations (better process). Other bifunctionals are created, some with fastness (better quality) or only fixation degree (better environment/economy) in mind.

Reactive dyes have good fastness properties owing to the bonding that occurs during dyeing. Cotton is made of cellulose molecules which react with the dye .During reactive dyeing the H atom in the cellolose molecule combines with the cl atom in the dyeing process and results in a bond. Trifunctional dyestuffs also exist.

Tie-dye

Tie-dye is a process of resist dyeing textiles or clothing which is made from knit or woven fabric, usually cotton; typically using bright colors. It is a modern version of traditional dyeing methods used in many cultures throughout the world. "Tie-dye" can also describe the resulting pattern or an item which features this pattern. Tie-dyeing became fashionable in the West in the late 1960s and early 1970s as part of hippie style. It was popularized in the United States by musicians such as John Sebastian, Janis Joplin, The Grateful Dead and Joe Cocker.

Tie-dyeing is accomplished by folding the material into a pattern, and binding it with string or rubber bands. Dye is then applied to only parts of the material. The ties prevent the entire material from being dyed. Designs are formed by applying different colors of dyes to different sections of the wet fabric. A wet t-shirt is much easier to use rather than just dyeing on a dry t-shirt. Once complete, the material is rinsed, and the dye is set.

Dyes

Although many different kinds of dyes may be used, most tie-dyers now dye with Procion MX fiber reactive dyes. This class of dyes works at warm room temperatures; the molecules permanently bind with cellulose based fibers (cotton, rayon, hemp, linen), as well as silk, when the pH is raised. Soda ash (sodium carbonate) is generally used to raise the pH and is either added directly to the dye, or in a solution of water in which garments are soaked before dyeing. They do not fade with washing, but sunlight will cause the colors to fade over time. Place in the freezer to hold over time.

Traditional tie-dye

The earliest surviving examples of pre-Columbian tie-dye in Peru date from 500-800A.D. Their designs include small circles and lines, with bright colors including red, yellow, blue, and green.

Shibori includes a form of tie-dye that originated in Japan. It has been practiced there since at least the eighth century. Shibori includes a number of labor-intensive resist techniques including stitching elaborate patterns and tightly gathering the stitching before dyeing, forming intricate designs for kimonos. Another shibori method is to wrap the fabric around a core of rope, wood or other material, and bind it tightly with string or thread. The areas of the fabric that are against the core or under the binding would remain undyed.

Tie-dye techniques have also been used for centuries in the Hausa region of West Africa, with renowned indigo dye pits located in and around Kano, Nigeria. The tie-dyed clothing is then richly embroidered in traditional patterns. It has been argued that the Hausa techniques were the inspiration for the hippie fashion.

Plangi and tritik are Indonesian words, derived from javanese words, for methods related to tie-dye, and bandhna is a term from India, giving rise to the Bandhani fabrics of Rajasthan. Ikat is a method of tie-dyeing the warp or weft before the cloth is woven. Tie-dyeing was known in the US by 1909. Later in the 20th Century, tie-dye became associated with the Hippie movement.

Mudmee tie-dye

Mudmee tie-dye is mainly created in Thailand and neighboring part of Laos. It uses different shapes and colors than other types of tie-dye, and the colors are, in general, more subdued. Another difference is that base color is black.

Folds and patterns

Below is a list of common modern tie-dyeing folds and patterns.

Spiral

Spiral patterns are created by gathering a small section,usually with a clothes pin or a kitchen fork, in the middle of the fabric and slowly rotating the piece creating pleats of fabric arranged in swirls around a central point. It is then gathered into a flat round bundle and the different wedges of the circular bundle are usually dyed different colors to create a greater spiral effect.

V

The 'V' shape is achieved by folding a shirt in half vertically, then a line is drawn diagonally from the shoulder area down to the center fold of the shirt. The fabric is then accordingly folded along the line and bound into one or more areas to which the dye is applied. This will show in the shape of a 'V'.

Random

This category can hold several different patterns, the majority of which have nothing to do with each other; they can be combinations or they can be as chaotic as bundling the item to be dyed.

Random circles

This effect is made by tying knots with string or elastic bands in different places. The more fabric that is tied, the larger the circles.

Peace Signs

The Peace Sign can be made by folding a t-shirt in half, drawing a half circle, then the center line and arm of the peace sign. The shirt is folded along the lines and tied using rubber bands. The dye is applied to form the outline of the peace sign then a lighter color is used to fill in the background colors.

Dye

A dye can generally be described as a colored substance that has an affinity to the substrate to which it is being applied. The dye is generally applied in an aqueous solution, and may require a mordant to improve the fastness of the dye on the fiber.

Both dyes and pigments appear to be colored because they absorb some wavelengths of light preferentially. In contrast with a dye, a pigment generally is insoluble, and has no affinity for the substrate. Some dyes can be precipitated with an inert salt to produce a lake pigment, and based on the salt used they could be aluminum lake, calcium lake or barium lake pigments.

Dyed flax fibers have been found in the Republic of Georgia dated back in a prehistoric cave to 36,000 BP. Archaeological evidence shows that, particularly in India and Phoenicia, dyeing has been extensively carried out for over 5000 years. The dyes were obtained from animal, vegetable or mineral origin, with no or very little processing. By far the greatest source of dyes has been from the plant kingdom, notably roots, berries, bark, leaves and wood, but only a few have ever been used on a commercial scale.

Organic dyes

The first human-made (synthetic)

organic dye, mauveine, was discovered by William Henry Perkin in 1856. Many thousands of synthetic dyes have since been prepared.

Synthetic dyes quickly replaced the traditional natural dyes. They cost less, they offered a vast range of new colors, and they imparted better properties to the dyed materials. Dyes are now classified according to how they are used in the dyeing process.

Acid dyes are water-soluble anionic dyes that are applied to fibers such as silk, wool, nylon and modified acrylic fibers using neutral to acid dyebaths. Attachment to the fiber is attributed, at least partly, to salt formation between anionic groups in the dyes and cationic groups in the fiber. Acid dyes are not substantive to cellulosic fibers. Most synthetic food colors fall in this category.

Basic dyes are water-soluble cationic dyes that are mainly applied to acrylic fibers, but find some use for wool and silk. Usually acetic acid is added to the dyebath to help the uptake of the dye onto the fiber. Basic dyes are also used in the coloration of paper.

Direct or substantive dyeing is normally carried out in a neutral or slightly alkaline dyebath, at or near boiling point, with the addition of either sodium chloride (NaCl) or sodium sulfate (Na2SO4). Direct dyes are used on cotton, paper, leather, wool, silk and nylon. They are also used as pH indicators and as biological stains.

Mordant dyes require a mordant, which improves the fastness of the dye against water, light and perspiration. The choice of mordant is very important as different mordants can change the final color significantly. Most natural dyes are mordant dyes and there is therefore a large literature base describing dyeing techniques. The most important mordant dyes are the synthetic mordant dyes, or chrome dyes, used for wool; these comprise some 30% of dyes used for wool, and are especially useful for black and navy shades. The mordant, potassium dichromate, is applied as an after-treatment. It is important to note that many mordants, particularly those in the heavy metal category, can be hazardous to health and extreme care must be taken in using them.

Vat dyes are essentially insoluble in water and incapable of dyeing fibres directly. However, reduction in alkaline liquor produces the water soluble alkali metal salt of the dye, which, in this leuco form, has an affinity for the textile fibre. Subsequent oxidation reforms the original insoluble dye. The color of denim is due to indigo, the original vat dye.

Reactive dyes utilize a chromophore attached to a substituent that is capable of directly reacting with the fibre substrate. The covalent bonds that attach reactive dye to natural fibers make them among the most permanent of dyes. "Cold" reactive dyes, such as Procion MX, Cibacron F, and Drimarene K, are very easy to use because the dye can be applied at room temperature. Reactive dyes are by far the best choice for dyeing cotton and other cellulose fibers at home or in the art studio.

Disperse dyes were originally developed for the dyeing of cellulose acetate, and are water insoluble. The dyes are finely ground in the presence of a dispersing agent and sold as a paste, or spray-dried and sold as a powder. Their main use is to dye polyester but they can also be used to dye nylon, cellulose triacetate, and acrylic fibres. In some cases, a dyeing temperature of 130°C is required, and a pressurised dyebath is used. The very fine particle size gives a large surface area that aids dissolution to allow uptake by the fibre. The dyeing rate can be significantly influenced by the choice of dispersing agent used during the grinding.

Azoic dyeing is a technique in which an insoluble azo dye is produced directly onto or within the fibre. This is achieved by treating a fibre with both diazoic and coupling components. With suitable adjustment of dyebath conditions the two components react to produce the required insoluble azo dye. This technique of dyeing is unique, in that the final color is controlled by the choice of the diazoic and coupling components.

Sulfur dyes are two part "developed" dyes used to dye cotton with dark colors. The initial bath imparts a yellow or pale chartreuse color, This is aftertreated with a sulfur compound in place to produce the dark black we are familiar with in socks for instance. Sulfur Black 1 is the largest selling dye by volume.