Background : Cut and pierced cocoons are generated in large quantities in the state every year. Even though cut and pierced cocoons are having shell with silk filaments, these cannot be reeled. A good quality hand spun yarn better than dupion can be produced using such cocoons.
By using cut cocoon spinning machine a good hand spun yarn can be produced by soaking these cocoons in cold water and soda. The machine is very simple and can be easily operated by women, which helps in generating gainful employment. The raw material needed for this activity is easily available in different parts of the State. Spinning of yarn with cut cocoons can be done at their respective houses without involving hard manual labour and travel outside the village.
Technology Details : This machine is very simple and leg operated, “MedleriCharaka” used for spinning coarse wool has been suitably modified to suit the cut cocoon spinning. A spindle with flyer fixed on the spindle and rotated along with the flyer. Spun yarn is twisted and wound onto the bobbin automatically with the help of a yarn guide fixed on the flyer. The count of the yarn and amount of twist to be given can be controlled easily. The machine has been developed by using easily available material. The machine can be used by rural people without and major maintenance.
Recommendation : It is possible to produce 700 – 750 gms of hand spun yarn by suing one kilogram of cut cocoons. 5 to 6 days are required to produce one kilogram of spun yarn. The machine is capable of producing count range of 7 to 20 cotton count
Background: The recovery and quality of bisufibre obtained from basin refuse separating method (widely practiced in India ) is poor. The effective utilization forbisu waste would benefit both reelers and spun silk mills. It is in this context an indigenous bisu separating machine has been designed and fabricated. In view of non-availability of suitable machines to local conditions, the bisu separating machine has been designed fabricated and field tested at silk filature.
Technology Details : The machine works on the principle teasing action of sharp metal spikes. The indigenous bisu separating machine fabricated consists of feeding section, teasing section, bisu sheet vibrating arm, delivery system and pupa removal section. Basin refuse material is loaded manually onto a inclined feeding plate. Material is pushed into the main tank by coarse pointed pronged lever. Material is feed slowly to the main tank at uniform rate to enable efficient separation.
The bath consists of tank provided with perforated sheet slanting at an angle towards the delivery end of the machine. The main portion of the machine is arrangement of teasers in series, for separation of basin refuse. Teasers are arranged on the top of the tank and mechanism is operated to drop the separated pupa in a container. An oscillating arm with two rods in parallel is provided at the delivery end of the bath. Separated bisu sheet is pulled out slowly by metal roller with coarse pins.
Recommendations : Machine is capable of separating the steam stifled cocoon basin refuse without any damage. Machine requires less space and is suitable capacity for medium scale filature operations (400 kg to 600 kg / 8 hours). Bisufibre generated is better compared to the methods followed presently in the industry.
Background : In Industry, soap and soda method of degumming is being practiced. The amount of soap and soda varies from one processor to another. There is no standard method and measurement of duration, quantity of chemicals, temperature etc. most of them are cottage sector processors. This affects the quality if silk. Standardization and scientific approach of degumming process is essential to retain the inherent qualities of luster, strength and elongation properties of silk after degumming.
Technology Details : Natural gum, sericin present in the raw silk yarn should be removed before the silk goes for dyeing in case of soft silk or loom state finished fabrics. But for high twisted yarn fabrics, raw yarn is woven into fabric and later degummed which needs extra care.
Optimum degumming of yarns is achieved at 4% soap and 4% soda at boil for 45 mins. Optimum degumming of fabrics can be achieved at 4% soap and 8% soda at boil for 45 mins. For bleaching, 1gpl of sodium hydro sulphate is sufficient in degumming bath. Use of soft water is essential.
Advantages : Degumming is called the heart of silk processing. Under degumming affects the wash fastness and other fastness properties. Over degumming affects strength properties. Hence optimum degumming is very essential to ensure the silk quality. This also reduces the over usage of chemicals and in turn load of the effluent is reduced.
Preliminary evaluation : A survey was carried out at Bangalore urban and ruralprocessing units. It was found that there was no standard method of quantity of chemicals, temp, duration for degumming among processors. Duration and various percentage of chemicals were tried in lab, and optimum process parameters were calculated after testing the strength and fastness properties of degummed silk.
Field evaluation : Through the members of Bangalore silk printers Association and dyers Association.Article was published in journals for the benefit of dyers. Students of B.Tech wereinducted to take up project work onthis subject. In training programmes of the institute, trainees were taught about the technology.
Cost benefit : Reduction in process cost by 20-25%. Reduces environmental pollution.
Background: Water plays significant role in silk processing. Silk processing is a cottage industry with majority of sources available being hard water. Most of the silk processing houses utilize hard water which adversely affects the quality of silk such as improper degumming and dyeing, less color yield etc. It also leads to higher chemical consumption, causing environmental pollution due to high load effluents.
Technology Details: Hardness less than or equal to 50 ppm is ideal for silk processing. It is necessary to treat water used in the processing units with water softeners.
Advantages: Improves silk quality and colouryield. reduces environmental pollution reduces the cost of processing.
Preliminary evaluation: Survey was carried out at various processing units at Doddaballpur, Bangalore urban, Kollegala, Kallur( KHDC processing unit) etc. water samples were collected and tested for hardness .It was found to be more than 250ppm. Effluent load was also found to be more. Keeping in view the hardness of water with respect to degumming , bleaching, dyeing and printing, various chemicals and dye stuffs, requisite guideline have been evolved.
Field evaluation: Water softeners were installed at processing centers to show the advantages of using treated water. Training programmes were conducted. Articles were published in textile journals to educate the processors.
Cost benefit: Reduces environmental pollution. Reduces the cost of chemicals by 15%. Color yield is increased by 20%.
Background: It was found that dyeing and printing chemicals are sensitive to atmospheric conditions and lose their strength. This has an influence in quality of degumming, bleaching, dyeing, and printing. Most of the silk processing units are cottage sectors and follow age old practice of family business. They are not aware of the importance to maintain a good inventory system.
Technology Details: In order to increase the life of chemicals, they have to be stored in polythene bags and kept in air tight containers. Longer period of storage to be avoided.
Advantages: Proper storage helps in optimum utilization of chemicals. Quality of silk is improved. Reduction in process cost. Reduction in environmental pollution.
Preliminary evaluation: Survey was carried out at various processing centers. Chemical storage conditions and inventory was studied. Trials were carried out with these chemicals .They were stored in open, semi open, open conditions for the period from 15 days to 45 days. These chemicals were used in silk processing to assess the quality of silk and the strength of chemicals were evaluated.
Field evaluation: Cottage sector processors were educated that longer the period of storage, chemicals lose its strength. Also chemicals which are not properly stored will be ineffective for the purpose. Demonstration and training programmes were conducted. Technology was made available through publications. B.Tech students and Msc home science students were inducted for project work on the subject.
Cost benefit: 10- 15 % of processing cost reduction . Consumers are benefited in terms of improvement in serviceability of the fabric.
Background: Technically, degumming of silk should be carried out in alkali media and dyeing should be carried out in acidic media. Silk, being a protein fiber, gets affected by alkali. But in practice, in cottage sectors, degumming and dyeing is carried out in a same bath. This is a age old practice. Single bath dyeing leads to wastage of chemicals, dyestuffs. It also affects the quality of silk. The effluent load is also high, causing environmental pollution.
Technology Details: First bath- degumming for 45 min at boil in a pH of 10-11 , second bath- After washing the material from first bath, dyeing for 30 min at 90 °C in acidic media.
Advantages: Dyed material feels soft and supple. Colour yield is better as the turbidity of dying bath reduces to almost zero. Quantity of dye stuff used is substantially less and hence reduction in cost of production. Less load on effluent.
Preliminary evaluation: Survey was carried out at various processing centers and studied the method of yarn dyeing. Experiments were carried out in lab comparing both single bath method dyeing and separate bath method dyeing. Colour values were measured using spectrophotometer and K/S values were evolved.
Field evaluation: B tech (Text) students were inducted to carry out as their projects after the lab findings. Articles was published in textile magazine in English and kannada for the benefit of processors. Educated the dyers at training programs.
Cost benefit: Reduction of chemicals by 20-25%.Colour yield is improved. Less load on effluent.
Background: In silk printing, thickeners used in the recipe constitute nearly 70 %. There are several commercial thickeners available in the market. The main draw back in the commercially available thickeners is the cost factor. Silk printing sector is a small scale industry, finds difficult to afford for this. Also to use the natural thickeners in the process of a natural fiber thus making it eco-friendly.
Technology Details: Carbohydrates based cereals/grains which are found to have good viscosity and are easily washable are considered for this study. Ex: Maida, Raagi, Rice, Jowar, Wheat. They all are natural and having pH of 6.5-7. Hence of cost of neutralization is also nil. Reducing agents, defoaming agents are not required, which reduces the cost of printing substantially.
Advantages: Easily available, can be self-prepared. Reduction in the cost of printing. Eco-friendly processing.
Preliminary evaluation: All trials carried out in the lab. It is a new concept and hence none of the industry is aware of this.
Field evaluation: Field trials were carried out through Bangalore silk printers association by inducting a M.Sc Home Science college student as a dissertation work.
Cost benefit: Reduction in printing cost by 45%.
Background: Silk being a natural filament, has unique characteristics like luster, softness, toughness(strength) and elongation etc. Artificial dyes are used in dyeing of silk. Towards eco-friendly approach, natural colors are. Which are of plant origin are used to colour the natural filament.
Technology Details: More than 50 natural shades are developed with the locally available plant products like root, bark, leaves, seed, fruit etc. To name some, Mulberry root & fruit, Onion skin, Hybiscusflower, Royal palm flower, Sandal wood, Nagalingapushpa, Cheeku seeds, Gungea seeds, Annato seeds, Sugarcane scalp, Termeric, Merrygold flower, Kokkumfruit, Dry scalp of Rajma seeds and green gram and many more. Fresh solutions were extracted in the suitable media (neutral, acidic, alkali) and applied on silk yarns and fabrics to get different shades of brown, green, orange, red, yellow and violet.
Advantages: Natural colours are very fast to washing and light. They are non-carcinogenic and eco-friendly. Less load on effluent.
Preliminary evaluation: More than 50 shades were obtained during the training programs, SIPA conducted by weavers service center, GOI at KSSRDI campus. Locally available material was used in the training.
Field evaluation: M.sc, B.Tech students of Bangalore University were inducted in dyeing of silk with natural colours through their project work, dissertation work. More than 10 articles were published in various magazines in kannada and English languages. A Ph.D work of a Home science college scholar was also carried out on this theme. “Dyeing with Garciniaindica fruit extract for infant garments “. Her Ph.D work was sponsored by UGC. Workshop conducted on the subject called ’Green Route’ at Home science college focusing on the usage of natural dyes on silk.
Two Ph.D programmes of Home science college, Bangalore university have been registered during 2011-12 on natural dyeing to be carried out at KSSRDI campus. One being ‘Micro encapsulation of functional fabrics using Nagalingapushpa fruit extract.’ Another being ‘ Revitalization of dyeing of silk using selective dye yielding plants of Manipur’( as the scholar is from Manipur dist.)
Background: Silk is a natural filament . It consists of around 20-30 % of sericin, natural gum which needs to be removed before subjecting silk into further process of dyeing, printing and finishing. A chemical, sodaash (sodium carbonate) is used along with alkali soap is used for degumming of silk. These chemicals not only affects the silk, but also pollute the environment. Mulberry twigs, after pruning, are used as a fuel and lot of mulberry ash is available which can be effectively used to degum silk.
Technology Details: Soaking of mulberry ash for 10-12 hrs in water, filtered ash water has pH of 10-10.7.Degumming of silk yarn can be carried using this strain. Treat at boil for one hour. Degummed silk yarn subjected to strength and elongation test.
Advantages: Elongation improves by 13% when compared to traditional way of soap and soda method. Naturally available mulberry stalks can be used .Eco friendly processing.
Preliminary evaluation: New concept. Encouraged by the word ASH of soda ash chemical. Mulberry ASH was dissolved in water to find out the pH, as pH require to gum is 11.
Field evaluation: An article has been published in ReshmeKrushi published by Dept of Sericulture , GOK, for the benefit of processors who are environmental conscious.
Background: Silk is a most beautiful ,natural protein fiber. Dyeing of silk with natural colours has the limitations of all the rainbow colours. Natural herbal colours have limited shades. To overcome this, colours which are used in food industry and pharmaceutical industry are explored. These permissible synthetic food colours belongs to acidic dye group which are also suitable for colouring protein fibers.
Technology Details: They are water soluble and are effectively used in beverages, toothpaste, bakery, Jams & jellies ,tablets &capsules. They are used on silk like any other acid colours.
Advantages: Food dyes are very safe to use on silk. It can overcome the limitations of natural colours. Dry cleaning fastness is very good for food colours. Hence they can be considered in terms of social-economic values. They are also eco-friendly.
Preliminary evaluation: It is a completely new concept to use food colours on textiles. Survey of food colours was carried out to find out the technical feasibility. Trials were carried out at lab.
Field evaluation: This study was materialized by inducting a M.Sc Home science college student. Educate the dyers at IHTP training programmes.
Background: Presently, in industry, the soap and soda method of degumming is in practice. Heavy alkali used in degumming reduces the strength and thus the serviceability of the fabric is affected. The effluent also has high load and causes environmental pollution. This study was taken to evolve an eco-friendly degumming of silk which retains the natural luster, strength of silk after processing.
Technology Details: Treated water( soft ) is used for degumming at high temperature and pressure . No chemicals are used. Sericin can also be extracted in pure form which has bio-molecular value and found application in cosmetic & Medical industry.
Advantages: Eco friendly process. Effluent load is almost nil. Sericin extraction in pure form. Silk looks lustrous maintaining its tenacity and elongation.
Preliminary evaluation: Trails were carried out at lab using pressure cooker initially. Further, trials were conducted at peenya silk processing unit using high temp & pressure dyeing keir.
Field evaluation: The technology was made known to processors through Bangalore dyers association.A batch of B.Tech students were encouraged to carry out projects based on the concept. Articles have been published in local journals. The technology was administered in IHTP programmes.
Cost benefit: Cost is reduced in terms of chemicals as no chemicals are used in this technology. Only cost of KEIR need to be incurred at one time. Process is environmental friendly.
Background: PM cocoons serves as a female parent for the production of CB layings at grainages. In Karnataka, nearly 50-60 tons of male PM cocoons and excess PM cocoons are rejected at grainages and seed area. These cocoons are mixed with inferior CB cocoons to produce courser variety of yarns or dupion. PM yarn when testedfor quality was found to be very fine and having less degumming loss. These characters are favorable for a weaver / processor.PM yarn has good tenacity And elongation also. These characters can be exploited to produce a Naati silk fabric named Kousheya
Technology Details: PM cocoons are separatelyreeled and the yarn was tested for gum loss, strength and elongation. These parameters were compared with CB yarn. Gum loss was least(19%) and tenacity was on par with CB yarn ( 3.5 gm/de) . A specialty fabric was produced using only PM yarn in the weft. The fabric looks more lustrous than CB fabric. This was named ‘KOUSHEYA’, to be given a geographical identification.
Advantages: Kousheya can cater to the special group of consumers who wants Desi products. Geographical identification of this fabric may mark Karnataka in global level as PM is only grown in Karnataka.
Preliminary evaluation: Different cocoons were testedunder UV light foe male and female segregationfor another study. It was found that PM cocoons were having uniform yellow shade both under ordinary light and under UV light. But BV cocoons were white under ordinary light but found mix of yellow and white when observed under UV light. This study initiated a new field of research for breeding.
Field evaluation: A sample of Kousheya produced with the help of a private reeler/weaver. The concept was presented at national seminar at Mysore. An article was published in’ Reshmekrushi‘ published by Dept of Sericulture , GOK in local language.
Recommendation: Good PM mixes with inferior CB cocoons to produce a yarn which fetches less prize can be profitably converted to produce special yarn to cater to the need of special group of customers. Pm can go to international market as DESI product.
Background: Silk being a natural fiber, having more luster, tenacity and elasticity.Use of detergents for washing are harmful to silk. Silk is a protein fiber and gets affected byalkali . Commercial detergents are alkaline in nature. To ensure silk friendly washing at consumer level, a new method was evolved. Rita nut(soap nut) and sikakai is used in India for washing hair since long time. The same concept is used to wash silk, as silk and hair are both protein filaments.
Technology Details: Washing agents should contain saponin.Washing of silk and silk blends with Bilwa fruit ( Aegelamarmelos) extract which consists of 19% saponin , helps silk retain its original luster and removing dirt , making process eco-friendly.
Advantages: Process is eco- friendly, consumer friendly and incur less cost. The process is techno- economical.
Preliminary evaluation: Pure silkand cotton/silk blended fabrics were artificially stained with ink, tea, soil, ice cream etc. Freshly prepared Rita nut (Supindusmukorossi), Sikakai( Acacia concinna) and Bilwa were used to remove stains/dirt of silk and blended fabric. This was compared with commercial eazy liquid soap.
Field evaluation: A batch of B.Tech studentswas inducted to carry out this findings. The student’s project was approved by Karnataka State Council for Science & Technology ( KSCST).
Background: Environmental friendly processing of silk is the need of the hour. Towards this, natural colors were substituted for synthetic dyes. Majority of natural dyes require mordents to give substantivity. Common mordents which are in use are metallic salts except alum. Metallic salts are carcinogenic in nature and are harmful. Natural filament silk ,dyed with natural colours and synthetic mordents does not make the process wholly eco friendly. Hence natural mordents were explored to replace the metallic salts.
Technology Details: Tanin found in plants serves as a very good mordent. Tannin form a strong complex with protein as polyphenolic compound contains sufficient hydroxyl group. Tea contains natural tannin contents. A KSSRDI product called ‘melbericha’ was used along with commercially available green tea and Taj tea as mordents. To dye silk with natural dye Annatto seeds. Results were compared for fastness to washing ,light and dry cleaning. K/S values were determined using spectrophotometer. The shades were compared with pantone shade card.
Eco friendly processing.Less expensive.
Pre treatment of silk for natural dyeing is an important process. To make the process eco friendly natural tannins were constantly experimented. Tea tannins were found to be sufficient to use as a mordent.
Field evaluation: The findings were confirmed by inducting a M.Sc Home Science (textile & clothing) student as her dissertation work.
Background: Guar gum, a natural gum used in silk printing is becoming expensive. Economic replacement of appropriate thickener is the need of the hour for industry. Thickener plays an important role in printing paste. Thickener should be able to impart stickiness and plasticity to the printing paste. Thickeners constitute nearly 75% of the printing paste. Hence directly contribute towards the cost of printing. A microbial gum called ‘XANTHANE’ which is profusely used in food industry and pharmaceutical industry was explored for the textile application.
Technology Details: Basically thickeners are high molecular weight compounds giving viscous paste in water. Xanthane gum is in printing paste along with usual ingredients. 8% of guar gum can be effectively by i% of xanthane gum. After printing the silk fabric, usual process of steaming, curing, and washing was carried out. Then the fabric was subjected to various tests viz; thickness, strength, stiffness, colour fastness to rubbing, colour fastness to washing and perspiration. The results are effective and encouraging.
Advantages: 1% of xanthane gum is sufficient as against 8% of guar gum to get the required viscosity. Its eco friendly product, Safer as already being used in food and pharmaceutical industry. 1% of xanthane gum works towards cost effectiveness.
Preliminary evaluation: Xanthanegum is being used in bakery, dairy products, beverages, antibiotic suspensions, paints and pigments, Bio fibers, novelty bath soaps, shower gell etc. But textile application is the novel and innovative concept.
Field evaluation: The study was carried out by inducting a batch of B.Tech (tex) students, there by student folks are first introduced to the new concept for their future development. Printing was carried at Swarnakala printers, associate of Bangalore silk printers Association. A research paper was presented at national seminar held during oct 2013 at KSSRDI, Bangalore.
Cost benefit: Less expensive because 1 % is used which has the major share (75%) in a printing paste. Eco-friendly, safe and biodegradable.