A General Synthetic Method for 1,1'-Bis(diacetylene-group)-Connected Ferrocene and π-Electronic S... more A General Synthetic Method for 1,1'-Bis(diacetylene-group)-Connected Ferrocene and π-Electronic System.-Under modified Eglinton oxidative coupling conditions, it is possible to generate 1,1'-diethynylferrocene in situ from a trimethylsilyl-protected precursor (I) and to react it with other terminal alkenes (III).-(YOSHINO,
Dyes are colored, ionizing, aromatic organic compounds. The chemical nature of a dye is determine... more Dyes are colored, ionizing, aromatic organic compounds. The chemical nature of a dye is determined by the chemical and physical properties of the colorant present in it. Spectroscopic and chromatographic analysis of different colorant extracts is needed to get an idea about its chemical constituents/composition. The presence of colorant and its chemical nature was ascertained by spectroscopic and chromatographic analysis of the dye extract. Column chromatography was used in some cases to isolate the colorant molecules in different plant extracts. UV-visible analysis of aqueous extract and FT-IR analysis of methanolic extract were carried out. HPLC was also recorded to get the idea about chemical entity of dye molecule. These isolation and colorant characterization techniques are extremely helpful and give very precise results to establish dye nature and type.
A Mild and Highly Selective N-Benzoylation of Cytosine and Adenine Bases in Nucleosides with N-Be... more A Mild and Highly Selective N-Benzoylation of Cytosine and Adenine Bases in Nucleosides with N-Benzoyltetrazole.-N-Benzoyltetrazole (III), stable for months at 4 • C under nitrogen, is investigated as a mild and selective reagent for benzoylation of nucleic acid bases. Independent of the addition of 2 equiv. (III), no dibenzoylation is observed under the conditions shown. An equimolar mixture of (IVb) and (VIIb) is selectively monobenzoylated; no bisbenzoylation is detected.-(BHAT, B.;
Purpose The purpose of this study is to check the effectivity of plasma in the natural dyeing of ... more Purpose The purpose of this study is to check the effectivity of plasma in the natural dyeing of polyester fabric using four natural dyes – Turkey red, Lac, Turmeric and Catechu using plasma and alum mordant. The surface modification on the polyester fabric by plasma along with the use of benign mordant alum is studied. The enhancement of dyeability in polyester fabric with natural dyes is the main focus. Due to surface modification, the wettability increases, which leads to better dye uptake. Better dye uptake and better dye adherence are the main objectives. Design/methodology/approach Plasma-mediated natural dyeing is the main design of this research work. The effect of plasma treatment on surface modification of synthetic fabric polyester and its subsequent effects on their dyeing with different natural dyes, namely, Turkey red, Lac, Turmeric and Catechu are studied. The dyeability was further enhanced by the use of alum as mordant. The main focus is on the betterment of natural...
PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum ... more PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum whose fruit pulp showed high dye contents. It is an abundantly available shrub in the north eastern forests of India.Design/methodology/approachDye extraction was carried out by conventional heating and sonicator. The dyebility of the aqueous extract of melastoma was evaluated for dyeing cotton fabric by two methods – sonication and conventional heating. The purpose of using sonication was for betterment of dye uptake, improved dye adherence and good wash and light fastnesses.FindingsThe test results showed that choosing this dyeing method produced improved results. The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and as a result, reduced wastes, makes it the established best available technique in the natural dyeing industry. Use of sonicator shows marked enhancement for cotton dyed fabric. Typical bath liquor to fabric ratio for co...
PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum ... more PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum whose fruit pulp showed high dye contents. It is an abundantly available shrub in the north eastern forests of India.Design/methodology/approachDye extraction was carried out by conventional heating and sonicator. The dyebility of the aqueous extract of melastoma was evaluated for dyeing cotton fabric by two methods – sonication and conventional heating. The purpose of using sonication was for betterment of dye uptake, improved dye adherence and good wash and light fastnesses.FindingsThe test results showed that choosing this dyeing method produced improved results. The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and as a result, reduced wastes, makes it the established best available technique in the natural dyeing industry. Use of sonicator shows marked enhancement for cotton dyed fabric. Typical bath liquor to fabric ratio for co...
... The Babool bark primarily consists of tannins of two types-Hydrolyzable tannins and Proanthoc... more ... The Babool bark primarily consists of tannins of two types-Hydrolyzable tannins and Proanthocyanidins. Natural Product Radiance, July-August 2002 Catech,u Babaal bark acid. ... The chemical constituents of the fruits are anthraquinones, chebulic acid and hydrolysable tannins. ...
In the present time, in view of a lot of national and international awareness of environmental is... more In the present time, in view of a lot of national and international awareness of environmental issues and pollution controls, natural dyes appear to be the ideal choice. These dyes are obtained from renewable resources, have no health hazards, sometimes act as health cure, practically have no or mild chemical reaction involved in their preparation, and pose no disposal problems. They are harmonized with nature and can be handled very easily and safely. There are some problems encountered in the use of vegetable/natural dyes as well. Some of these problems are nonavailability because of difficulty in collection, bulk isolation of dye stuff, standardization of dyeing procedure, color yield, complexity of dyeing process, and reproducibility of shade. But in the 21st century, maintaining a safe environmental balance becomes even more important, and that's why natural dyes can be regarded as safe and green alternatives.
Preparation of silver nanoparticles have been carried out using aqueous extract of lemon leaves (... more Preparation of silver nanoparticles have been carried out using aqueous extract of lemon leaves (Citrus limon) which acts as reducing agent and encapsulating cage for the silver nanoparticles. These silver nanoparticles have been used for durable textile finish on cotton and silk fabrics. Remarkable antifungal activity has been observed in the treated fabrics. The antimicrobial activity of silver nanoparticles derived from lemon leaves showed enhancement in activity due to synergistic effect of silver and essential oil components of lemon leaves. The present investigation shows the extracellular synthesis of highly stable silver nanoparticles by biotransformation using the extract of lemon leaves by controlled reduction of the Ag ? ion to Ag 0. Further the silver nanoparticles were used for antifungal treatment of fabrics which was tested by antifungal activity assessment of textile material by Agar diffusion method against Fusarium oxysporum and Alternaria brassicicola. Formation of the metallic nanoparticles was established by FT-IR, UV-Visible spectroscopy, transmission electron microscopy, scanning electron microscopy, atomic force microscopy.
Dyeing of cotton fabric with different extracts of plants such as Acacia bark, Mahonoia naupalens... more Dyeing of cotton fabric with different extracts of plants such as Acacia bark, Mahonoia naupalensis, Salvia, Canna indica, Rhododendron, Cosmos, Terminalia arjuna, Ocimum Sanctum, and Rubia cordifolia has been described in this chapter. The fastness properties have been ascertained and the CIE Lab values and shade cards have been mentioned. Needless to mention that some treatment methods are different, and the color of each dye on cotton is very unique.
Natural dyeing can proceed only after the fabric or yarn is scoured in mild soap. Unique pre- and... more Natural dyeing can proceed only after the fabric or yarn is scoured in mild soap. Unique pre- and posttreatments have helped in adherence of the natural colorant. The chemistry of treatments pre or post is slightly different; however, the purpose remains the same. Many important factors as scouring, desizing, and mordanting generally play a vital role in dye adherence or overall fastness of dyed material. The locking of the natural colorant in the fabric on a permanent basis during the dyeing process is of the key importance for a dyer.
Wool dyeing with natural plant colorants have been practiced for a long time. Newer sources of na... more Wool dyeing with natural plant colorants have been practiced for a long time. Newer sources of natural dyes have been used for pure wool dyeing. Animal proteins, like wool dye best in acidic conditions and are weakened by alkalines. Sources of natural dyes which are used, primarily give color to wool generally in acid dye bath. Plants used are Celosia, Nerium, Hollyhock, Hibiscus mutabilis, Caryatia, Tegetus, Rambutan, and Curcuma. Some innovation at the stage of pretreatment has been mentioned in this section. Wool being proteineous has good dye adherence ability which makes dyed yarn very evenly dyed with the above mentioned dye sources.
Purpose Natural dyes are mostly used for dyeing of natural fibre textiles to improve their eco-fr... more Purpose Natural dyes are mostly used for dyeing of natural fibre textiles to improve their eco-friendly features. For successful commercial use of natural dyes, the appropriate and standardized dyeing techniques need to be adopted. Appropriate scientific techniques or procedures need to be derived from scientific studies on dyeing methods, dyeing process variables, dyeing kinetics and compatibility of selective natural dyes with minimal use of hazardous chemicals. Design/methodology/approach In the present study, different enzymes (protease, amylase, xylanase, pectinase, phytase) were used efficiently with Rubia dye by using simultaneous and two-step processes; both the processes were developed with an aim for conservation of time and energy, for the ease of industrial use. The highlights of the study are twofold: eco-friendly natural dyeing by using enzyme replacing metal mordant and room temperature dyeing, which is a completely new concept. Findings Experiments showed that enzyma...
A revival interest in the use of natural dyes in textile coloration has been growing, and there i... more A revival interest in the use of natural dyes in textile coloration has been growing, and there is a pressing need for the availability of natural dye-yielding plants. This is a result of the stringent environmental standards imposed by many countries in a response to the toxic and allergic reactions associated with synthetic dyes. This resurgence of natural dyes has encouraged screening of newer natural dye sources. These new sources of dyes were used on silk as shades produced on silk gave an idea about color produced and other dyeing parameters like fastness and color scale with natural dyeing.
A General Synthetic Method for 1,1'-Bis(diacetylene-group)-Connected Ferrocene and π-Electronic S... more A General Synthetic Method for 1,1'-Bis(diacetylene-group)-Connected Ferrocene and π-Electronic System.-Under modified Eglinton oxidative coupling conditions, it is possible to generate 1,1'-diethynylferrocene in situ from a trimethylsilyl-protected precursor (I) and to react it with other terminal alkenes (III).-(YOSHINO,
Dyes are colored, ionizing, aromatic organic compounds. The chemical nature of a dye is determine... more Dyes are colored, ionizing, aromatic organic compounds. The chemical nature of a dye is determined by the chemical and physical properties of the colorant present in it. Spectroscopic and chromatographic analysis of different colorant extracts is needed to get an idea about its chemical constituents/composition. The presence of colorant and its chemical nature was ascertained by spectroscopic and chromatographic analysis of the dye extract. Column chromatography was used in some cases to isolate the colorant molecules in different plant extracts. UV-visible analysis of aqueous extract and FT-IR analysis of methanolic extract were carried out. HPLC was also recorded to get the idea about chemical entity of dye molecule. These isolation and colorant characterization techniques are extremely helpful and give very precise results to establish dye nature and type.
A Mild and Highly Selective N-Benzoylation of Cytosine and Adenine Bases in Nucleosides with N-Be... more A Mild and Highly Selective N-Benzoylation of Cytosine and Adenine Bases in Nucleosides with N-Benzoyltetrazole.-N-Benzoyltetrazole (III), stable for months at 4 • C under nitrogen, is investigated as a mild and selective reagent for benzoylation of nucleic acid bases. Independent of the addition of 2 equiv. (III), no dibenzoylation is observed under the conditions shown. An equimolar mixture of (IVb) and (VIIb) is selectively monobenzoylated; no bisbenzoylation is detected.-(BHAT, B.;
Purpose The purpose of this study is to check the effectivity of plasma in the natural dyeing of ... more Purpose The purpose of this study is to check the effectivity of plasma in the natural dyeing of polyester fabric using four natural dyes – Turkey red, Lac, Turmeric and Catechu using plasma and alum mordant. The surface modification on the polyester fabric by plasma along with the use of benign mordant alum is studied. The enhancement of dyeability in polyester fabric with natural dyes is the main focus. Due to surface modification, the wettability increases, which leads to better dye uptake. Better dye uptake and better dye adherence are the main objectives. Design/methodology/approach Plasma-mediated natural dyeing is the main design of this research work. The effect of plasma treatment on surface modification of synthetic fabric polyester and its subsequent effects on their dyeing with different natural dyes, namely, Turkey red, Lac, Turmeric and Catechu are studied. The dyeability was further enhanced by the use of alum as mordant. The main focus is on the betterment of natural...
PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum ... more PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum whose fruit pulp showed high dye contents. It is an abundantly available shrub in the north eastern forests of India.Design/methodology/approachDye extraction was carried out by conventional heating and sonicator. The dyebility of the aqueous extract of melastoma was evaluated for dyeing cotton fabric by two methods – sonication and conventional heating. The purpose of using sonication was for betterment of dye uptake, improved dye adherence and good wash and light fastnesses.FindingsThe test results showed that choosing this dyeing method produced improved results. The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and as a result, reduced wastes, makes it the established best available technique in the natural dyeing industry. Use of sonicator shows marked enhancement for cotton dyed fabric. Typical bath liquor to fabric ratio for co...
PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum ... more PurposeThe purpose of this paper is to evaluate the dyeing potentials of Melastoma malabathricum whose fruit pulp showed high dye contents. It is an abundantly available shrub in the north eastern forests of India.Design/methodology/approachDye extraction was carried out by conventional heating and sonicator. The dyebility of the aqueous extract of melastoma was evaluated for dyeing cotton fabric by two methods – sonication and conventional heating. The purpose of using sonication was for betterment of dye uptake, improved dye adherence and good wash and light fastnesses.FindingsThe test results showed that choosing this dyeing method produced improved results. The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and as a result, reduced wastes, makes it the established best available technique in the natural dyeing industry. Use of sonicator shows marked enhancement for cotton dyed fabric. Typical bath liquor to fabric ratio for co...
... The Babool bark primarily consists of tannins of two types-Hydrolyzable tannins and Proanthoc... more ... The Babool bark primarily consists of tannins of two types-Hydrolyzable tannins and Proanthocyanidins. Natural Product Radiance, July-August 2002 Catech,u Babaal bark acid. ... The chemical constituents of the fruits are anthraquinones, chebulic acid and hydrolysable tannins. ...
In the present time, in view of a lot of national and international awareness of environmental is... more In the present time, in view of a lot of national and international awareness of environmental issues and pollution controls, natural dyes appear to be the ideal choice. These dyes are obtained from renewable resources, have no health hazards, sometimes act as health cure, practically have no or mild chemical reaction involved in their preparation, and pose no disposal problems. They are harmonized with nature and can be handled very easily and safely. There are some problems encountered in the use of vegetable/natural dyes as well. Some of these problems are nonavailability because of difficulty in collection, bulk isolation of dye stuff, standardization of dyeing procedure, color yield, complexity of dyeing process, and reproducibility of shade. But in the 21st century, maintaining a safe environmental balance becomes even more important, and that's why natural dyes can be regarded as safe and green alternatives.
Preparation of silver nanoparticles have been carried out using aqueous extract of lemon leaves (... more Preparation of silver nanoparticles have been carried out using aqueous extract of lemon leaves (Citrus limon) which acts as reducing agent and encapsulating cage for the silver nanoparticles. These silver nanoparticles have been used for durable textile finish on cotton and silk fabrics. Remarkable antifungal activity has been observed in the treated fabrics. The antimicrobial activity of silver nanoparticles derived from lemon leaves showed enhancement in activity due to synergistic effect of silver and essential oil components of lemon leaves. The present investigation shows the extracellular synthesis of highly stable silver nanoparticles by biotransformation using the extract of lemon leaves by controlled reduction of the Ag ? ion to Ag 0. Further the silver nanoparticles were used for antifungal treatment of fabrics which was tested by antifungal activity assessment of textile material by Agar diffusion method against Fusarium oxysporum and Alternaria brassicicola. Formation of the metallic nanoparticles was established by FT-IR, UV-Visible spectroscopy, transmission electron microscopy, scanning electron microscopy, atomic force microscopy.
Dyeing of cotton fabric with different extracts of plants such as Acacia bark, Mahonoia naupalens... more Dyeing of cotton fabric with different extracts of plants such as Acacia bark, Mahonoia naupalensis, Salvia, Canna indica, Rhododendron, Cosmos, Terminalia arjuna, Ocimum Sanctum, and Rubia cordifolia has been described in this chapter. The fastness properties have been ascertained and the CIE Lab values and shade cards have been mentioned. Needless to mention that some treatment methods are different, and the color of each dye on cotton is very unique.
Natural dyeing can proceed only after the fabric or yarn is scoured in mild soap. Unique pre- and... more Natural dyeing can proceed only after the fabric or yarn is scoured in mild soap. Unique pre- and posttreatments have helped in adherence of the natural colorant. The chemistry of treatments pre or post is slightly different; however, the purpose remains the same. Many important factors as scouring, desizing, and mordanting generally play a vital role in dye adherence or overall fastness of dyed material. The locking of the natural colorant in the fabric on a permanent basis during the dyeing process is of the key importance for a dyer.
Wool dyeing with natural plant colorants have been practiced for a long time. Newer sources of na... more Wool dyeing with natural plant colorants have been practiced for a long time. Newer sources of natural dyes have been used for pure wool dyeing. Animal proteins, like wool dye best in acidic conditions and are weakened by alkalines. Sources of natural dyes which are used, primarily give color to wool generally in acid dye bath. Plants used are Celosia, Nerium, Hollyhock, Hibiscus mutabilis, Caryatia, Tegetus, Rambutan, and Curcuma. Some innovation at the stage of pretreatment has been mentioned in this section. Wool being proteineous has good dye adherence ability which makes dyed yarn very evenly dyed with the above mentioned dye sources.
Purpose Natural dyes are mostly used for dyeing of natural fibre textiles to improve their eco-fr... more Purpose Natural dyes are mostly used for dyeing of natural fibre textiles to improve their eco-friendly features. For successful commercial use of natural dyes, the appropriate and standardized dyeing techniques need to be adopted. Appropriate scientific techniques or procedures need to be derived from scientific studies on dyeing methods, dyeing process variables, dyeing kinetics and compatibility of selective natural dyes with minimal use of hazardous chemicals. Design/methodology/approach In the present study, different enzymes (protease, amylase, xylanase, pectinase, phytase) were used efficiently with Rubia dye by using simultaneous and two-step processes; both the processes were developed with an aim for conservation of time and energy, for the ease of industrial use. The highlights of the study are twofold: eco-friendly natural dyeing by using enzyme replacing metal mordant and room temperature dyeing, which is a completely new concept. Findings Experiments showed that enzyma...
A revival interest in the use of natural dyes in textile coloration has been growing, and there i... more A revival interest in the use of natural dyes in textile coloration has been growing, and there is a pressing need for the availability of natural dye-yielding plants. This is a result of the stringent environmental standards imposed by many countries in a response to the toxic and allergic reactions associated with synthetic dyes. This resurgence of natural dyes has encouraged screening of newer natural dye sources. These new sources of dyes were used on silk as shades produced on silk gave an idea about color produced and other dyeing parameters like fastness and color scale with natural dyeing.
Journal of textile and apparel technology and management, 2009
Aqueous extract of pericarp of Garcinia was prepared by sonicator for quick extraction of the col... more Aqueous extract of pericarp of Garcinia was prepared by sonicator for quick extraction of the colorant and has been used for dyeing cotton, silk and wool yarn. 1-2 % of premordanting with metal salts of Al, Sn, Fe, Cr and Cu was done. Fe, cu and Cr are best suited mordants for garcinia. The hue color ranged from camel brown to dark chocolate brown. The color strength K/S has been found to be very good in dyed samples. The fastness properties have also been evaluated and were found to be well above the acceptable limits.
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