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Silk - Ethics & Ecology

Silk - Ethics & Ecology

 

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The sericulture in China

The most important meaning among the silk-spidering insects is the Real Silk Spinner. The Bombyx mori silk worm has been cultivated for nearly 5,000 years in China on trays with mulberry leaves (hence the name "mulberry silk spinner"). Long before the emergence of the Roman Empire, when the tribes were still living in primitive huts in Europe, the silkworms were already completely domesticated. For thousands of years she has not been able to survive without human welfare and feeding. There are no wild mulberry moths or moths living in the wilderness.

 

Through the millennia of captive breeding, the silk moth Bombyx mori has become a blind butterfly that can not fly and only lives a few days. During this time he lays about 400 eggs and dies after four to five days. The moth has no eating tools and can not eat any food. The Seidenzucht occurs mostly in large industrially marked plants. In recent decades, silk has become a mass product without any appreciation. The enormous drop in prices and the concentration on economically efficient large farms have not only damaged quality, but also worsened the growing conditions of silk farmers and polluted the environment.
 
 
Silk Rearing in INdia
In India, mainly the Japanese oak silk moth Antheraea yamamai and Eri- and Mugaseidenraupen live. Traditionally, the wild collection in India is native. In the forests, the cocoons left by the butterflies are collected and sent for further processing. As part of programs to generate income for the poor rural population, small agricultural projects have been developed in recent years in many states to breed the Tussahide Moth. Therefore, the designation of Tussah silk as "wild silk" is no longer correct today.

Influenced by the past of the wild collection of cocoons and the philosophy of nonviolence u.a. Seed breeding is often practiced by Mahatma Gandhi in the sense of "ahimsa" (sankskrit: non-infringing).

Mainly two methods are used. On the one hand, the cocoons of the silk caterpillars are not processed until the butterfly has hatched. The cocoon is dissolved by the moth by bodily fluids. A hole is etched into it, through which the butterfly can fly away. The cocoon is thus damaged, and it is no longer possible to unwind an endless thread. The relatively short pieces of thread must first be spun to allow further processing (in the weaving). The traditional wild silk fabrics from Tussah silk were also produced by this method.
In the Tussah silk crab of the Japanese oak silk moth, it is possible to provide the completed cocoons with a small cut and then continue to let them go their natural development. The moth "discovers" the hole created for it and slips away without damaging the cocoon. This method of silk fiber production is more effective in terms of the quality of the silk fibers.
 
Part of the silk is processed in artisanal small businesses, where - sometimes manually spun - hand looms individual silk fabrics.

 

The differences of textile fabrics


To obtain the mulberry silk (formerly: breeding silk), the cocoons are dried after their completion by the silkworm. In the first step of processing, the cocoons are softened in a hot alkaline solution to dissolve the sericin, the silk glue, and to be able to rewind the silk thread. It can be obtained from a cocoon up to 1500 m long continuous filament (reel silk). From inferior or damaged parts of the cocoon, the short fibers are processed into spun silk (spider silk).

The thread of the mulberry silk moth is, due to five millennia of breeding, a very fine and regular fiber. After removal of the sericin, the filament (the size) is almost white. Mulberry silk fabrics have a strong shine, feel smooth and fall soft and supple. They correspond to the usual idea of a silk fabric.

 

In the wild collection or Ahimsa method, it is not possible to unwind filaments endlessly, as the cocoons were damaged by the moth or by humans. Thus, only relatively short fibers can be obtained, which must subsequently be spun so that a textile material can be weaved from them. Furthermore, the "Indian" silkworms have in common that their silk threads have a yellowish to brownish color and are also much more irregular. This resulted in the typical wild silk structure.

If the silk fibers are well debased and spun into fine yarns, very soft and non-slip fabrics with interesting textures result. This is reinforced by spinning and weaving techniques of artisanal production, which are difficult to reproduce industrially. Often the three silk types Tussah, Eri and Muga are mixed to vary the fabric properties. Tussah silk fabrics are less shiny, heavier and more "robust" than mulberry silk fabrics.

Ecological and social aspects

If the Seidenzucht is operated as a biological or bio-dynamic agriculture and the appropriate criteria are fulfilled, a certification according to EU 834/2007, the so-called eco-regulation, as "controlled biological animal husbandry" (kbT) can take place. The feed for the caterpillars without herbicides and pesticides and animal husbandry without hormones and the use of other chemical agents. The raw silk extraction, the unwinding and the boil off, must also be kbT compliant.

The processing of raw silk into textile fabrics can then be carried out according to the rules of the Global Organic Textile Standard (GOTS) or the IVN Best certification. With these two quality seals, ecological, sustainable and social parameters are included in the assessment.

The standards set out the list of possible substances that can be used throughout the textile chain, which wastewater qualities must be met, and that fair working conditions must be met. The social parameters are based on the core labor standards of the International Labor Organization (ILO).

Regular quality and residue controls are also mandatory for obtaining one of the two certificates, as well as the complete documentation and traceability of the end product to its origin (traceability). This ensures that consumers have a textile in their hands that has actually been manufactured under fair, ecological and sustainable criteria.

In addition to the incomparable properties and the attractive appearance of natural fiber silk, this means that the wearer or buyer can afford the luxury of an exclusive piece of clothing in good conscience. Whether from organic silk or Ahimsa silk - that may decide the personal taste.

© Dr. Matias Langer 2014

 

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Note on the pricing of organic silk

The higher price of organic and non-violent silk compared to conventionally produced silk is caused by

  • lower yield through smaller but higher quality cocoons in organic nutrition and breeding
  • higher production costs due to lower production volumes (scaling effect) and ecologically compatible processing and processing (spinning, twisting, weaving, dyeing)
  • higher labor costs due to social and fair working conditions
  • additional costs of the annual certification