Preamble
This is the one hundredth and eleventh 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
Sulfur dyes are so called because they contain sulfur (S) atom(s). Sulfur dyes have been used as cotton dyes for over 100 years. The range of sulfur dyes is limited to dull colors from yellow to black. None are very bright and reds are almost absent apart from a few dull maroons and bordeaux shades. The fibers that are most readily colored with sulphur dyes are the natural and man-made cellulosic fibers.
Sulfur Dyes. See - http://www.alibaba.com/product-gs/442451744/sulfur_dyes.html - for further information about these dyes.
Little is known about the chemical structure of sulfur dyes, even though they are thought to contain a thiazine ring.
Portion of a sulfur dye molecule.
Note: The complete structure is still not known. The thiazine ring is the –N=C-S- portion of the above structure, where N, C and S are nitrogen, carbon and sulfur respectively.
Courtesy of reference[1].
Sulfur dyes are water insoluble and so must first be reduced into a soluble form. They are produced by chemically reacting compounds as p-aminophenol and dinitronaphthalene with sulfur. A simplistic scheme for their production is given below.
Production of a sulfur dye.
Note: The old spelling of Sulfur is used in this schematic.
Courtesy reference[1].
Dyeing with Sulfur Dyes
Sulfur dyes are insoluble in water. An aqueous solution of the sulfur dye is effected by reacting some sulfur dyes with sodium sulphide and others with sodium hydrosulfite. The role of sodium sulfide or sodium hydrosulfite is to reduce sulfur to produce the water soluble or leuco form of the dye. In some instances the addition of sodium carbonate may be necessary to achieve the desired alkalinity. In this reduced or leuco form, sulphur dyes are substantive to cellulose fibers. To achieve dye exhaustion, it is necessary to add an electrolyte such as sodium chloride to the dye liquor.
To obtain adequate penetration and a satisfactory rate of dyeing, the dye liquor is heated. This has a two-fold effect:
(i) It enlarges the entry and internal voids of the amorphous regions of the fiber polymer system enabling deeper penetration into the fiber.
(ii) It increases the kinetic energy of all the constituents, thereby increasing the rate of dye uptake by the fiber polymer system.
Once the dye is within the amorphous regions of the fiber polymer system, the reduced sulfur (which is soluble) is converted to its original insoluble form, via an oxidation treatment with a mild reagent such as sodium perborate.
Printing with Sulfur Dyes
Sulfur dyes are generally not used for printing textile materials.
Properties of Sulfur Dyes
Light-Fastness
The light-fastness rating of sulfur dyes is about 4, which translates as fair. After-treatments with metal salts improve the light-fastness rating to 5. The initial fair rating is attributed to the instability of the chromophores of the sulfur dyes with respect to UV sunlight. On the other hand, metal ions improve the stability of the sulfur dye chromophores with respect to UV sunlight, increasing their light-fastness rating.
Wash-Fastness
Sulfur dyes have a wash-fastness rated between 3-4, which is fair due to the relatively large size and partly to the aqueous insolubility of the dye molecule. The general lack of any significant polar groups in the dye molecule implies that the dye is retained in the amorphous regions of the fiber polymer system due to its size, aqueous insolubility and van der Waals forces of attraction.
Color Range of Sulfur Dyes
Sulfur dyes have a color range, which is limited to black, brown, blue and olive. Sulfur dyed textile materials are also dull. Their dullness can be attributed to the greater scattering of the incident white light, possibly due to aggregates of the dyed molecules trapped and entangled in the amorphous regions of the fiber polymer system.
Bronzing
Sulfur dyed textile materials show a metallic or bronze sheen, which is termed bronzing. This effect gives rise to poor rub-fastness, and moreover, gives the textile material a less appealing appearance. Bronzing mostly occurs in heavy or dark shades for the following reasons or combinations thereof:
(i) Exposure to excessive heavy dyeing.
(ii) Exposure of the textile materials to atmosphere during dyeing causing premature oxidation.
(iii) Failure to remove excess dye liquor following dyeing.
(iv) Providing an insufficient amount of sodium sulfide in the dye liquor to keep the dye in its soluble form.
The bronzing effect can be removed by an after-treatment in an aqueous solution of dilute sodium sulfide, which will remove excess dye molecules that are present on the surface of the textile material.
Cost of Sulfur Dyes
The relative low cost of sulfur dyes has meant their continued use particularly for dark colors, such as navy and black.
References:
[1] E.P.G. Gohl and L.D. Vilensky, Textile Science, Longman Cheshire, Melbourne (1989).
[2] A Fritz and J. Cant, Consumer Textiles, Oxford University Press, Melbourne (1986).
This is the one hundredth and eleventh 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
Sulfur dyes are so called because they contain sulfur (S) atom(s). Sulfur dyes have been used as cotton dyes for over 100 years. The range of sulfur dyes is limited to dull colors from yellow to black. None are very bright and reds are almost absent apart from a few dull maroons and bordeaux shades. The fibers that are most readily colored with sulphur dyes are the natural and man-made cellulosic fibers.
Little is known about the chemical structure of sulfur dyes, even though they are thought to contain a thiazine ring.
Note: The complete structure is still not known. The thiazine ring is the –N=C-S- portion of the above structure, where N, C and S are nitrogen, carbon and sulfur respectively.
Courtesy of reference[1].
Sulfur dyes are water insoluble and so must first be reduced into a soluble form. They are produced by chemically reacting compounds as p-aminophenol and dinitronaphthalene with sulfur. A simplistic scheme for their production is given below.
Note: The old spelling of Sulfur is used in this schematic.
Courtesy reference[1].
Dyeing with Sulfur Dyes
Sulfur dyes are insoluble in water. An aqueous solution of the sulfur dye is effected by reacting some sulfur dyes with sodium sulphide and others with sodium hydrosulfite. The role of sodium sulfide or sodium hydrosulfite is to reduce sulfur to produce the water soluble or leuco form of the dye. In some instances the addition of sodium carbonate may be necessary to achieve the desired alkalinity. In this reduced or leuco form, sulphur dyes are substantive to cellulose fibers. To achieve dye exhaustion, it is necessary to add an electrolyte such as sodium chloride to the dye liquor.
To obtain adequate penetration and a satisfactory rate of dyeing, the dye liquor is heated. This has a two-fold effect:
(i) It enlarges the entry and internal voids of the amorphous regions of the fiber polymer system enabling deeper penetration into the fiber.
(ii) It increases the kinetic energy of all the constituents, thereby increasing the rate of dye uptake by the fiber polymer system.
Once the dye is within the amorphous regions of the fiber polymer system, the reduced sulfur (which is soluble) is converted to its original insoluble form, via an oxidation treatment with a mild reagent such as sodium perborate.
Printing with Sulfur Dyes
Sulfur dyes are generally not used for printing textile materials.
Properties of Sulfur Dyes
Light-Fastness
The light-fastness rating of sulfur dyes is about 4, which translates as fair. After-treatments with metal salts improve the light-fastness rating to 5. The initial fair rating is attributed to the instability of the chromophores of the sulfur dyes with respect to UV sunlight. On the other hand, metal ions improve the stability of the sulfur dye chromophores with respect to UV sunlight, increasing their light-fastness rating.
Wash-Fastness
Sulfur dyes have a wash-fastness rated between 3-4, which is fair due to the relatively large size and partly to the aqueous insolubility of the dye molecule. The general lack of any significant polar groups in the dye molecule implies that the dye is retained in the amorphous regions of the fiber polymer system due to its size, aqueous insolubility and van der Waals forces of attraction.
Color Range of Sulfur Dyes
Sulfur dyes have a color range, which is limited to black, brown, blue and olive. Sulfur dyed textile materials are also dull. Their dullness can be attributed to the greater scattering of the incident white light, possibly due to aggregates of the dyed molecules trapped and entangled in the amorphous regions of the fiber polymer system.
Bronzing
Sulfur dyed textile materials show a metallic or bronze sheen, which is termed bronzing. This effect gives rise to poor rub-fastness, and moreover, gives the textile material a less appealing appearance. Bronzing mostly occurs in heavy or dark shades for the following reasons or combinations thereof:
(i) Exposure to excessive heavy dyeing.
(ii) Exposure of the textile materials to atmosphere during dyeing causing premature oxidation.
(iii) Failure to remove excess dye liquor following dyeing.
(iv) Providing an insufficient amount of sodium sulfide in the dye liquor to keep the dye in its soluble form.
The bronzing effect can be removed by an after-treatment in an aqueous solution of dilute sodium sulfide, which will remove excess dye molecules that are present on the surface of the textile material.
Cost of Sulfur Dyes
The relative low cost of sulfur dyes has meant their continued use particularly for dark colors, such as navy and black.
References:
[1] E.P.G. Gohl and L.D. Vilensky, Textile Science, Longman Cheshire, Melbourne (1989).
[2] A Fritz and J. Cant, Consumer Textiles, Oxford University Press, Melbourne (1986).
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