Preamble
For your convenience I have listed other posts on Japanese textiles on this blogspot:
Discharge Thundercloud
The Basic Kimono Pattern
The Kimono and Japanese Textile Designs
Traditional Japanese Arabesque Patterns (Part I)
Textile Dyeing Patterns of Japan
Traditional Japanese Arabesque Patterns (Part II)
Sarasa Arabesque Patterns (Part III)
Contemporary Japanese Textile Creations
Shibori (Tie-Dying)
History of the Kimono
A Textile Tour of Japan - Part I
A Textile Tour of Japan - Part II
The History of the Obi
Japanese Embroidery (Shishu)
Japanese Dyed Textiles
Aizome (Japanese Indigo Dyeing)
Stencil-Dyed Indigo Arabesque Patterns (Part V)
Japanese Paintings on Silk
Tsutsugaki - Freehand Paste-Resist Dyeing
Street Play in Tokyo
Birds and Flowers in Japanese Textile Designs
Japanese Colors and Inks on Paper From the Idemitsu Collection
Yuzen: Multicolored Past-Resist Dyeing - Part 1
Yuzen: Multi-colored Paste-Resist Dyeing - Part II
Introduction
The Idemitsu Museum of Arts was established by the late Sazo Idemitsu in 1966 in order to exhibit collections of Asian art that had been assembled during the previous half century by Sazo Idemitsu, founder of Idemitsu Kosan Co. Ltd.
Idemitsu Museum of Arts.
The Japanese silk paintings selected in this post were exhibited at the major art galleries in Queensland, NSW, South Australia, Western Australia and Victoria in 1982-1983. Japanese arts began in the Jōmon period (the Japanese neolithic cultural period extending from about 8,000 BC to 200 BC). In ancient times and through the Middle Ages, Japan introduced and subsequently assimilated art/culture initially from China and Korea and even as far away as Persia. In modern times, Japanese art/culture has accepted and then assimilated Western European culture in a unique fashion.
Japanese Paintings on Silk (from the Idemitsu Collection)[1]
Title: A Beauty.
Artist: Miyagawa Chōshun (1683-1753).
Kakemono: A Japanese unframed painting made on paper or silk and displayed as a wall hanging.
Colors on Silk.
Size: 88 x 33 cm.
Comment[1]: Chōshun designed no prints and produced only ukiyo-e paintings (i.e. literally 'pictures of a floating world': an Edo (1615 to 1868) school of painting concerned with the depiction of popular life). The pose of the woman is a standard one in the bijin-ga repertoire (a generic term for pictures of beautiful women in Japanese art): the girl walking with one foot coming forward, her head turned to look back over her shoulder, one hand holding her kimono at the waist.
Title: Beauties Admiring Paintings.
Artist: Katsukawa Shunshō (1726-1792).
Kakemono.
Colors on Silk.
Size: 70 x 123 cm.
Comment[1]: This painting is a masterpiece of Shunshō in which the artist has combined the fashionable taste for bijin-ga within a meticulously depicted landscape and garden setting. Eleven women are shown: with the exception of the two young girls who are dressed similarly in kimonos of a cherry blossom-on-red background pattern, each woman is carefully and skilfully painted in a different pose and kimono. Their complicated hairstyles were achieved by the use of binzashi: objects made of bone or metal that held their hair out flat on either side of the face.
Title: A Beauty Having A Smoke.
Artist: Utagawa Toyokuni (1769-1825).
Kakemono.
Colors on Silk.
Size: 101.5 x 36.0 cm.
Comment[1]: This is an informal portrait of a beauty having a smoke after washing her hair, with only her head and shoulders shown, a popular format since the late 18th century. The cotton printed cloth around her shoulders and the thin material of her outer garment show the incorporation of late 18th century fashion into this painting. Smoking was a fashionable pastime among the sophisticated demimonde of Edo and the woman is holding a typical Edo pipe with its long stem and very small bowl that permitted only a few puffs. Tobacco smoking had been introduced from Europe through the namban traders and then quickly adopted by fashionable society.
Title: Landscape Of Spring And Autumn.
Artist: Katsushika Hokusai (1760-1849).
Pair of Kakemono.
Colors on Silk.
Each Size: 70.2 x 27.3 cm.
Comment[1]: Hokusai is one of the world's great draftsman, immortalised through his sets of landscape prints of which 'Thirty Six Views of Mount Fuji' is the masterpiece. He was a prodigious creator of prints, drawings and paintings - he is thought to have produced over 30,000 designs. Together with Hiroshige, he revitalised ukiyo-e in the early 19th century when the tradition was dying due to lack of new themes.
In this pair of scrolls, spring is on the right, with the back view of the man energetically polling his boat and cherry blossom above. The autumn scene is on the left, it depicts three travellers talking together as they pause on their way through the autumn mountains, whose high peeks and deep ravines show the influence of Western techniques. Both scrolls have the feeling of a moment caught in time and both are infused with an airy, genial atmosphere through the harmony of the composition and the color scheme.
Title: Two Beauties In The Wind.
Artist: Teisai Hokuba (1771-1844).
Kakemono.
Colors on Silk.
Size: 95.0 x 34.6 cm.
Comment[1]: Two women bend into a fierce wind as they endeavour to progress in the face of a storm. One is trying to open her umbrella while the other looks around in alarm at the sudden change of weather. Light snow is falling and the wind is tossing the pine tree on the left and playing havoc with the women's kimonos. The Sumida River behind them is rough and rain has come with the snow. In the background can be seen buildings, including a five storied pagoda.
Title: Drooping Cherry Tree And Bush Clover.
Artist: Sakai Hōitsu (1761-1828).
Pair of Kakemono.
Colors on Silk.
Each Size: 108.6 x 39.7 cm.
Comment[1]: These scrolls are a distillation of Japanese aesthetics. They depict cherry blossoms and bush clover naturalistically rendered. As the symbols of spring and autumn respectively, they evoke the beauty of those seasons and the inevitable transition of time. The realisation of the short duration of such fragile beauty tinges our appreciation with a poignant sadness that is at the heart of Japanese aesthetics. The flowers are there, perfectly placed, with no extraneous background to distract. The composition is harmoniously balanced and since each flower grows in from the outer edge of the scroll the composition is unified. Each branch bears a poem written in Japanese script and the combination of literature, art and nature make this a superb statement of Japanese sensibility. The poem on the right is written on a long, narrow, paper strip termed tanzaku; that on the left is written on a decorative heavy paper square termed a shikishi. Both of these are standard shapes for poems in Japan and from the Momoyama period (1568 to 1615) to the present day. The shape of each format compliments the shape and tenor of their respective plants. The poems refer to the moving effect that a drooping cherry tree or white bush clover in the moonlight has upon an onlooker of the scene that is depicted.
Reference:
[1] J. Menzies and E. Capon, Japan: Masterpieces from the Idemitsu Collection, International Cultural Corporation of Australia Limited, Sydney (1982).
Preamble
For your convenience I have listed below the other posts in this series:
The Art of Jenny Kee - Part I
The Art of Jenny Kee - Part II
Introduction
Jenny Kee started her career by selling ethnic and retro clothing, cast-off Dior and Indian embroideries in 1960s London. She was born in 1947 to a Chinese father and Anglo-Italian mother. Jennifer Margaret Kee is not only a national fashion icon but an enduring figure thanks to her bright, eclectic style and fusion of fashion and art.
In 1972 saw Jenny Kee return to open her boutique, Flamingo Park. The success of the boutique drew fashion and textile designer Linda Jackson to Kee and together they created the iconic Kee colorful wool jumpers.
Iconic Jenny Kee jumper.
In 2012, Jenny Kee partnered with Australian label 'Romance Was Born'.
The Art of Jenny Kee - Part III[1]
The homewear shown below was sourced from reference[1] which is based on needlepoint/embroidery work with instructions and patterns by Alison Snepp based on Jenny Kee's designs. The theme for today's homewear is: 'The Earth'.
Embroidered Cushion and Cloth: After the Fire.
After the Fire (Detail View).
Inspiration: Ghost Gums.
Embroidered Cushion: Ghost Gums.
Embroidered Cushion: Floral Vision.
Embroidered Cushion: Floral Vision (Detail View).
Inspiration: Wattle.
Embroidered Cushion: Wattle.
Embroidered Bag and Jumper: Country.
Embroidered Cloth: Waratah.
Framed Embroidered Cloth: Waratah.
Inspiration: Black Opal.
Embroidered Cushion: Black Opal.
Inspiration: Earth Dreaming.
Embroidered Cushion: Earth Dreaming.
Reference:
[1] Jenny Kee Needlepoint, Simon & Schuster, Roseville (1993).
Preamble
Art Quilts have featured on this blogspot and so for your convenience I have listed below previous posts in this series:
Art Quilts - Part I
Art Quilts - Part II
Art Quilts - Part III
Art Quilts - Part IV
Art Quilts - Part V
Art Quilts - Part VI
Art Quilts - Part VII
Art Quilters of the Netherlands - Part I
Art Quilters of the Netherlands - Part II
Art Quilters of the Netherlands - Part III
Four Selected European Art Quilters - Part I
Four Selected European Art Quilters - Part II
Four Selected European Art Quilters - Part III
Art Quilts of Jane Sassaman
Art Quilts of Michael A. Cummings
Introduction
Art Quilts and ArtCloth has been with us for centuries. The medium of cloth enables artists to bring together different hues, techniques and concepts that would be stifled by the use of other media. It has grown from craft to art and it has done so seamlessly and without the usual fanfare when our male counterparts create a new art genre. It is mainly female focussed since we are such creative beings that when we were the gatherers and collectors we decided early in the piece that life would be so boring if our bedding, our clothes and cloth only had a functional purpose. Instead we demanded so much more that we made our bedding into Art Quilts, our clothes into wearable art and transformed our cloth into ArtCloth. In other words females created new art genres. It so no wonder we love our Art Quilts and our ArtCloths.
Art Quilts - Part VII[1]
Title: The Teapot/High Priestess: Card #2 in the Kitchen Tarot (1998).
Artist: Susan Shie.
Materials and Techniques: Fabric, fabric paint, jewellery, beads, wood, buttons, Indian handbags, lace, leather; painted, hand sewn, embroidered, airbrushed, and appliquéd.
Size: 87 x 55 inches (2.2 x 1.4 m).
Photograph courtesy of Brian Blauser.
Title: Flying Free #2 (1995).
Artist: Caryl Bryer Fallert.
Materials and Techniques: Cotton; hand dyed, painted, machine pieced and quilted.
Size: 93 x 82 inches (2.4 x 2.1 m).
Photograph courtesy of artist.
Title: Free Fall (2004).
Artist: Jeanette Gilks.
Materials and Techniques: Commercial cottons, upholstery materials; layered, machine stitched and embroidered, appliquéd, reverse appliquéd.
Size: 49 x 49 inches (1.2 x 1.2 m).
Photograph courtesy of Stephanie Stein.
Title: Moonlight (2007).
Artist: Jane Burch Cochran.
Materials and Techniques: Various fabrics, beads, buttons, paint, glove, doilies, embroidery thread; machine pieced and appliquéd, hand appliquéd and quilted.
Size: 77 x 61 inches (2 x 1.6 m).
Photograph courtesy of Pam Monfort.
Title: Crown of Crazy (2002).
Artist: Pamela Allen.
Materials and Techniques: Recycled and commercial fabrics, beads, safety pins, plastic eggs and fruit, stuffed elements; hand raw-edge appliqué, machine quilted, embellished.
Size: 53 x 40 inches (1.4 x 1 m).
Photograph courtesy of artist.
Title: Affirmation Quilt (2006).
Artist: Therese May.
Materials and Techniques: Fabric, acrylic paint, fabric paint, buttons, jewels; machine appliquéd, machine quilted by Jenny Michel.
Size: 71 x 61 inches (1.8 x 1.6 m).
Photograph courtesy of Richard Johns.
Title: Ohio Star Bar/Inspiration of the Wing (2003).
Artist: John W. Lefelhocz.
Materials and Techniques: Cotton, tulle net, printed paper, feathers; hand sewn.
Size: 58 x 65 inches (1.5 x 1.7 m).
Photograph courtesy of T. Craemer.
Title: Changing Planes (1992).
Artist: Miriam Nathan-Roberts.
Materials and Techniques: Cottons; machine pieced, appliquéd and quilted.
Size: 74 x 72 inches (1.9 x 1.8 m).
Photograph courtesy of artist.
Title: Pele (2006).
Artist: Jenny Hearn.
Materials and Techniques: Commercial prints, hand-dyed silks, chiffons, cottons; machine pieced and appliquéd, hand and machine embroidered and quilted.
Size: 65 x 72 inches (1.7 x 1.8 m).
Photograph courtesy of Dion Cuyler.
Title: American Heritage Flea Market (1987).
Artist: Terrie Hancock Mangat.
Materials and Techniques: Cotton, silk, buttons, beads, paint, pipe cleaners; photo transferred, hand embroidered, reverse appliquéd and appliquéd.
Size: 87 x 82 inches (2.2 x 2.1 m).
Photograph courtesy of artist.
Reference:
[1] M. Sielman, Masters: Art Quilts, Lark Books, New York (2008).
Preamble
For your convenience I have listed below the other post in this series:
Conversational Designer Patterns
Introduction
It is very important to develop a wealth of resources that you can draw on when you think you need to refreshen your art. Sometimes it may mean that you wish to explore a new technique or that you will change the medium that you are working with (e.g. from canvas to cloth). Other times you might feel that the Indy wearables you have created need a different repeat pattern. It is good to explore the work of others.
Abstract patterns are non-representational designs with freely drawn shapes and motifs and so do not contain a recognisable figurative or narrative element to the design. The designs can be as diverse as the patterning of tropical fish or the shapes string makes when stitched loosely on a piece of paper[1]. Whatever the technique or the medium that is employed it is the end result that captivates our imagination.
Abstract Designer Patterns[1]
Designer: Rachael Taylor.
Comment[1]: Black threads stitched on to handmade paper were used to generate this machine-embroidered collage. The artist remarked: 'The sewing machine was used deliberately at an incorrect setting and tension level to achieve a loose knotted style.'
Designer: Maryam Taheri.
Comment[1]: The work in entitled, 'Crazy'. This blue and orange digital design has a distinctly three dimensional appearance - almost like that of a scrunched up multicoloured metal foil.
Designer: Ed Jones.
Comment[1]: This screenprinted textile sample features a generously proportioned area of blue, looking like the sky over a network of cranes.
Designer: Louise Kallinicou.
Comment[1]: The sensitivity of the original collage has been retained in the complex image, which appears to rotate around a central vortex. The artist explains: 'Different layers have been rotated over each other to build up this four-way repeat. Certain layers vary in opacity in order to create the illusion of depth.'
Designer: Alex Russell.
Comment[1]: Leaves and stems wind and writhe in profusion in this strikingly colored pattern. The artist comments: 'Paintings loosely based on traditional textile patterns are digitally manipulated and colored to produce a repeat design for fashion fabrics.'
Designer: Pauline Holt for Jazzy Lily Hot Glass.
Comment[1]: Swirling molten glass has formed this pattern. The artist comments: 'This is a homemade lamp worked bead. The rich reds and golds are reminiscent of the colorful saris worn in the Indian State of Jaipur.'
Designer: Sara Sulemanji.
Comment[1]: Watery tones and flecks of contrasting colors give this piece of printed silk a feeling of movement and vivacity. The artist comments: 'This design is inspired by tropical fish and uses different print pastes, as well as pleating and folding techniques to change its shape.
Designer: Caroline MacNamara.
Comment[1]: Barcelona, one of the most photogenic cities in Europe, was the inspiration for this digital pattern.
Reference:
Drusilla Cole, Patterns, Laurence King, Publishing Ltd., London, 2007.
Preamble
This is the one hundredth and fourth post in the "Art Resource" series, specifically aimed to construct an appropriate knowledge base in order to develop an artistic voice in ArtCloth.
Other posts in this series are:
Glossary of Cultural and Architectural Terms
Units Used in Dyeing and Printing of Fabrics
Occupational, Health & Safety
A Brief History of Color
The Nature of Color
Psychology of Color
Color Schemes
The Naming of Colors
The Munsell Color Classification System
Methuen Color Index and Classification System
The CIE System
Pantone - A Modern Color Classification System
Optical Properties of Fiber Materials
General Properties of Fiber Polymers and Fibers - Part I
General Properties of Fiber Polymers and Fibers - Part II
General Properties of Fiber Polymers and Fibers - Part III
General Properties of Fiber Polymers and Fibers - Part IV
General Properties of Fiber Polymers and Fibers - Part V
Protein Fibers - Wool
Protein Fibers - Speciality Hair Fibers
Protein Fibers - Silk
Protein Fibers - Wool versus Silk
Timelines of Fabrics, Dyes and Other Stuff
Cellulosic Fibers (Natural) - Cotton
Cellulosic Fibers (Natural) - Linen
Other Natural Cellulosic Fibers
General Overview of Man-Made Fibers
Man-Made Cellulosic Fibers - Viscose
Man-Made Cellulosic Fibers - Esters
Man-Made Synthetic Fibers - Nylon
Man-Made Synthetic Fibers - Polyester
Man-Made Synthetic Fibers - Acrylic and Modacrylic
Man-Made Synthetic Fibers - Olefins
Man-Made Synthetic Fibers - Elastomers
Man-Made Synthetic Fibers - Mineral Fibers
Man Made Fibers - Other Textile Fibers
Fiber Blends
From Fiber to Yarn: Overview - Part I
From Fiber to Yarn: Overview - Part II
Melt-Spun Fibers
Characteristics of Filament Yarn
Yarn Classification
Direct Spun Yarns
Textured Filament Yarns
Fabric Construction - Felt
Fabric Construction - Nonwoven fabrics
A Fashion Data Base
Fabric Construction - Leather
Fabric Construction - Films
Glossary of Colors, Dyes, Inks, Pigments and Resins
Fabric Construction – Foams and Poromeric Material
Knitting
Hosiery
Glossary of Fabrics, Fibers, Finishes, Garments and Yarns
Weaving and the Loom
Similarities and Differences in Woven Fabrics
The Three Basic Weaves - Plain Weave (Part I)
The Three Basic Weaves - Plain Weave (Part II)
The Three Basic Weaves - Twill Weave
The Three Basic Weaves - Satin Weave
Figured Weaves - Leno Weave
Figured Weaves – Piqué Weave
Figured Fabrics
Glossary of Art, Artists, Art Motifs and Art Movements
Crêpe Fabrics
Crêpe Effect Fabrics
Pile Fabrics - General
Woven Pile Fabrics
Chenille Yarn and Tufted Pile Fabrics
Knit-Pile Fabrics
Flocked Pile Fabrics and Other Pile Construction Processes
Glossary of Paper, Photography, Printing, Prints and Publication Terms
Napped Fabrics – Part I
Napped Fabrics – Part II
Double Cloth
Multicomponent Fabrics
Knit-Sew or Stitch Through Fabrics
Finishes - Overview
Finishes - Initial Fabric Cleaning
Mechanical Finishes - Part I
Mechanical Finishes - Part II
Additive Finishes
Chemical Finishes - Bleaching
Glossary of Scientific Terms
Chemical Finishes - Acid Finishes
Finishes: Mercerization
Finishes: Waterproof and Water-Repellent Fabrics
Finishes: Flame-Proofed Fabrics
Finishes to Prevent Attack by Insects and Micro-Organisms
Other Finishes
Shrinkage - Part I
Shrinkage - Part II
Progressive Shrinkage and Methods of Control
Durable Press and Wash-and-Wear Finishes - Part I
Durable Press and Wash-and-Wear Finishes - Part II
Durable Press and Wash-and-Wear Finishes - Part III
Durable Press and Wash-and-Wear Finishes - Part IV
Durable Press and Wash-and-Wear Finishes - Part V
The General Theory of Dyeing – Part I
The General Theory of Dyeing - Part II
Natural Dyes
Natural Dyes - Indigo
Mordant Dyes
Premetallized Dyes
Azoic Dyes
Basic Dyes
Acid Dyes
Disperse Dyes
Direct Dyes
Reactive Dyes
Sulfur Dyes
Blends – Fibers and Direct Dyeing
The General Theory of Printing
There are currently eight data bases on this blogspot, namely, the Glossary of Cultural and Architectural Terms, Timelines of Fabrics, Dyes and Other Stuff, A Fashion Data Base, the Glossary of Colors, Dyes, Inks, Pigments and Resins, the Glossary of Fabrics, Fibers, Finishes, Garments and Yarns, Glossary of Art, Artists, Art Motifs and Art Movements, Glossary of Paper, Photography, Printing, Prints and Publication Terms and the Glossary of Scientific Terms, which has been updated to Version 3.5. All data bases will be updated from time-to-time in the future.
If you find any post on this blog site useful, you can save it or copy and paste it into your own "Word" document etc. for your future reference. For example, Safari allows you to save a post (e.g. click on "File", click on "Print" and release, click on "PDF" and then click on "Save As" and release - and a PDF should appear where you have stored it). Safari also allows you to mail a post to a friend (click on "File", and then point cursor to "Mail Contents On This Page" and release). Either way, this or other posts on this site may be a useful Art Resource for you.
The Art Resource series will be the first post in each calendar month. Remember - these Art Resource posts span information that will be useful for a home hobbyist to that required by a final year University Fine-Art student and so undoubtedly, some parts of any Art Resource post may appear far too technical for your needs (skip over those mind boggling parts) and in other parts, it may be too simplistic with respect to your level of knowledge (ditto the skip). The trade-off between these two extremes will mean that Art Resource posts will hopefully be useful in parts to most, but unfortunately may not be satisfying to all!
Introduction
Dyes can be classified according to their application (e.g. disperse dyes), their nature (e.g. acidic dyes) and their structure (e.g. azoic dyes). The first classification is what art and craft dyers gravitate to, whereas the last is what chemists prefer.
It should be noted that a mordant dye, a basic dye and an acidic dye could also be classified as an azoic dye - even though they are structurally different - so long as all three dyes contain at least one azo group (ie -N=N-) in their chemical make-up. However, not all mordant, basic and acidic dyes contain azo links and so in these cases, they could not be classified as an azoic dye.
Azoic dyes are also called naphthol dyes, ice colors or developed colors. They are labelled naphthol since they also contain a naphthol group. For example, the azoic dye, Congo Red, contains two azo linkages (-N=N-) separated by a di-phenyl group, with the opposite linkages attached to a naphthol group (see below).
White silk satin printed with azoic dyes.
Typically azoic dyes can be formed inside the fiber polymer systems. Firstly, a colorless component – naphthol - is dyed into the fabric polymer system and since this component is a small molecule it is easily absorbed into the hydrophilic fibers. Nitrous acid is added which reacts with the naphthol to form a highly reactive intermediate called a diazonium ion, which when added to a phenolic compound will yield a highly colored dye within the fiber.
Azoic dyeing takes place under cold conditions in order to prevent the production of undesirable side products. Levelness is a problem for azoic dyeing since it is heavily dependent on the even or uniform coverage of colorless components during the dyeing process. The dyeing generally produces bright and wash fast fabrics (especially reds and oranges). However, care must be taken to wash off any dyes formed on the fiber surface to prevent poor rubbing fastness.
Azoic dyes are generally used on man-made and natural cellulosic fibers (e.g. cotton, viscose etc.) and on silks, and in particular, they are used in batik dyeing. They are gradually being restricted to specialist dyeing applications.
Dyeing With Azoic Dyes
Coloring textile materials with azoic dyes involves the reaction with the fiber polymer system of the two components, which constitutes the azoic dye, namely, naphthol (also called the coupling component) and the diazo component (also called the base). Dyeing or printing with azoic dyes is therefore a multi-stage process.
In order to clarify this complex dyeing process let us follow the formation of Congo Red within the amorphous regions of the textile material. Congo Red is an azoic dye that is red in alkali and blue in an acid solution.
The first stage of dyeing with azoic dyes is called naphtholation, which involves dissolving 4-aminonaphthalene-1-sulfonic acid in water using sodium hydroxide (NaOH). The fiber is impregnated with this solution of naphthol. To assist penetration into the amorphous region of the fiber polymer system, a temperature of 80-85oC is used for viscose, but with cotton, room temperature is adequate. The impregnated textile materials are passed through rollers to remove excess solution from the material.
Stage 1: Chemical formula and structure of 4-aminonaphthalene-1-sulfonic acid.
Note: This naphthol molecule is firstly impregnated in the fiber polymer system.
Courtesy of reference [1].
The second stage of azoic dyeing, called diazotization involves the preparation of a diazo component by converting this component to a soluble diazonium salt, using sodium nitrite (NaNO2) and hydrochloric acid, which generates nitrous acid (HONO). This then reacts with 4,4’-benzidine to yield a diazonium salt. Diazonium salts are fairly unstable and so to decrease their reactivity, ice is usually added to the dye liquor.
Stage 2: A reactive species called a diazonium salt is produced.
Note: The 4,4’-benzidine reacts with nitrous acid to produce a diazonium salt. Only the cation of the salt is shown since the corresponding anion of this salt is in solution and so is not attached to the cation.
Courtesy of reference [1].
Once the fabric has been treated with naphthol it is passed through a liquor containing the diazonium salt to create a reaction that will generate the Congo Red dye in the amorphous region of the textile materials. It is at this stage that the –N=N- or azo link is formed which is the chromophore of the dye.
Stage 3: Formation of the Congo Red dye (bottom molecule).
Note: The naphthol molecules are shown on the left and right side of the diazonium salt. Both naphthol and diazonium salt react in the amorphous region of the fiber polymer system and on the surface to form an azoic dye called Congo Red. This reaction is referred to as coupling, since it couples the naphthol to the diazonium salt to produce the azoic dye (which is characterized by the azo links –N=N-).
Courtesy of reference [1].
It should be noted that the coupling reaction should occur in the amorphous regions of the fiber polymer system. Nevertheless, it is inevitable the coupling reaction will also occur on the surface of the fiber. The removal of the dye on the surface is essential, since azoic dyes are insoluble and unless removed, the textile materials will have poor rub-fastness. This removal is further enhanced by a thorough final rinse of the dyed material. Care must be taken at each stage of the dyeing process, that most of the dye formation occurs within the fiber polymer system and not on its surface.
Printing with Azoic Dyes
The application of azoic dye by printing is similar to that of dyeing except that the fabric impregnated with the coupling component features the printed design. This is followed by the application of the diazonium salt to produce the insoluble azoic dye. As in dyeing, care must be taken that the insoluble dye is formed within the fiber polymer system in order to reduce significantly the possibility of poor rub-fastness.
Properties of Azoic Dyes
Light Fastness
Dyes and printed azoic dyed textile materials have very good to excellent light fastness with ratings of about 6-7, which is due to the stable electronic configuration of its chromophores, which can resist very prolonged exposure to UV sunlight.
Wash Fastness
Wash fastness of azoic dyes is about 4-5, which translates as very good wash fastness of azoic dye and printed textile materials, which is due to the fact that azoic dyes are water insoluble.
Bright Colors
Azoic dyes are characterized by their very bright red and orange colors. Hence these dyes absorb all the incident white light, except light with the wavelength of red and orange.
Rub Fastness
At times azoic dyed and printed textile materials suffer from poor rub fastness (see above). It is important that after dyeing/printing the rinsing stage usually involves a soaping off using a detergent.
If all stages of azoic dyeing and printing are carefully controlled and appropriate rinse off is invoked, poor rub fastness is unlikely to occur.
Blinding
At times azoic dyes may cause a matt or delustered effect. This effect, called blinding, is more common on viscose than on cotton. It is thought that blinding occurs due to incident light becoming more scattered because of the uneven distribution of dye molecules within the amorphous regions of the fiber polymer system. Dye molecules in this region are lumped together or aggregated, and it is this aggregation that causes a greater deal of scattering. Its effect is greater in viscose than in cotton, in that the former has a higher percentage of amorphous regions, than the latter.
References:
[1] A. Fritz and J. Cant, Consumer Textiles, Oxford University Press, Melbourne (1986).
[2] E.P.G. Gohl and L.D. Vilensky, Textile Science, Longman Cheshire, Melbourne (1989).
Idemitsu Museum of Arts.
Title: Beauties Admiring Paintings.
Title: A Beauty Having A Smoke.
Title: Landscape Of Spring And Autumn.
Title: Two Beauties In The Wind.
Title: Drooping Cherry Tree And Bush Clover.
