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    3.1 Introduction

    A Tannery is a work shop where raw hides and skins are converted into

    leather by the application of astringent called tannin or tannic acid. The process

    of tanning has been appropriately referred to a`s a Series of baths in water

    containing certain ingredients. Large animals are said to have hides (e.g. cow

    hide, buffalo hide) and smaller animals are said to have skins (e.g. goat skin,

    sheep skin) 1.

    Tanning is an art by which putrescible animal hides and skins are preserved

    from decay and converted into non-perishable substance, known as Leather. Man

    has been aware of this art since the dawn of human civilization. Many ancient

    civilizations had evolved and perfected this art of making leather. The earliest

    records of such ancient civilization, those of Egypt, China and India, establish the

    fact that the art was well-known to the ancient people and was widely practiced.

    According to historians, the art of the tanning originated before the dawn of

    recorded history. Tanning has two types of processes, such as Vegetable Tanning

    (where vegetable tanning materials are employed); and Chrome Tanning (where

    the basic chromate is used). Earlier, Vegetable Tanning was in operation; but

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    today, almost all the tanneries process their leather through Chrome Tanning to

    reduce time and to produce quality leather.

    The Vegetable Tanning was comparatively harmless. This process is time-

    consuming taking 40 - 45 days to change from skin to finished leather. This is also

    called East India Tanning. With the increase in demand for finished leather in

    the world market, most of the tanneries have turned to Chrome Tanning, also

    called the Wet-Blue Tanning. In this process, various chemicals, fat liquor oil

    and dyes are used. The raw skins and hides are received in the tanneries in wet

    salted or dry salted form. The salt (Sodium Chloride) is used as a preservative and

    is first removed and then skins and hides are put into various processes, like

    Soaking, Liming, Airing, Fleshing and De-liming, followed by washing and


    Tanning is an integral part of the process of converting raw hides and skins

    into finished leather. It involves three types of products, viz. Raw to finish, Raw to

    Semi-finish and Semi-finish to Finish. Leather production technology has evolved

    from the cottage industry to a fully mechanized industry. The leather and leather

    products sector now represents one of the most important industrial sectors in

    India, significantly contributing to the national economy2.

    3.2 Historical Background of Leather Tanning Industry

    In the earlier years, leather industry was a cottage industry which employed

    rural labour in the process of tanning raw hides and skins that were available

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    locally. The tanning ingredients were lime, tanning bark from shrubs and trees like

    Pongam, Avaram, Konnam, Velam, Myrobalans and vegetable oil like pongam

    oil. The process of tanning takes 40 - 45 days to convert raw hides into semi-

    tanned. The semi-tanned hides were exported to the U.K. and other countries

    during the pre-independence periods. The price of semi-tanned hides and skins

    were controlled by the British. Hence, the tanners were at the mercy of the foreign

    buyers; and the transaction undertaken on contract basis by them with the

    foreigners extended to a period of about 3 months.

    After Independence, the tanners were allowed free trade and were quoting

    their own prices and exporting semi-finished leather to U.K. and other countries at

    competitive prices. From 1950s onwards, the tanning process had been shortened

    by 3-4 days due to the arrival of tanning chemicals. Gradually, machines were

    introduced in tanning and the Government had banned the export of semi-tanned

    hides and skins and wanted only finished leather to be exported. This made many

    tanneries to shift themselves to tanning finished leather and exporting them. In

    places where small tanners could not afford to have huge tanning machines,

    Co-operative Industrial Common Finishing Centers were opened to cater to the

    needs of small tanners who were engaged in finished leather tanning on job work

    basis. Such mechanized units are situated at Erode, Vaniyambadi, Pernambut and


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    Pre-historic people used to live by hunting animals. They felt that some

    kind of clothes were necessary to them in order to protect their body from heat,

    cold and rain. The pre-historic hunting man utilized the skins of the killed animals

    for his clothing. At that time, he might have observed that the raw hides and skins

    putrefied, if they were kept wet and dried out. The dried and hard skin was

    certainly inconvenient to him to wrap up his body. Thus, it would be only natural

    for him to try to soften the fur while drying it. In this attempt, the foundation of

    the art of tanning was laid by the pre-historic people in order to render the skin

    soft and convenient to wear it. The primitive men might also have noticed that the

    skins thus differed from the untreated skins. Hence, greasing and drying consisting

    of one among the many ways in which the primitive people tried to safeguard the

    animal skins3.

    It was in the East that the art of manufacturing leather developed to a

    considerable extent in early periods. The Egyptians, the Chinese, the Sumerians,

    the Babylonians besides Indians, had attained a high degree of skill and

    intelligence in making leather. In a museum in Berlin, there is a stone carving in

    which the operation of dressing a tigers skin is depicted. This granite depiction is

    estimated to be at least 4,000 years old4.

    Leather has also been found on Egyptian mummies. Among the articles

    belonging to Egypt and kept in the British museum, one can find a leather apron of

    a workman, besides leather shoes of various kinds5.

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    Hebrews of the Biblical times used oak bark in tanning and that the

    Romans, Greeks and Egyptians used lime to loosen the hair on hides. This process

    is used today also in most of the tanneries. In the earlier period, the Egyptians

    became familiar and had more knowledge in the manufacture of leather, which

    they used as coverings for stools, chairs, bed and cushions.

    In India, tanning and leather works have been practised since ancient times.

    These occupations were mainly carried out by a different caste called Chamars.

    The Rig-Veda refers to tanners as Chamars and the leather from animal skin

    were prepared by them. This evidently proves that the Indian tanning industry is as

    old as the Rig-Vedic hymns6.

    Dressing of skins by the application of fatty and albumin matters like

    tallow, oil, egg yolk, curd etc. is practised even today in most of the tanneries.

    Furs are dressed more or less in accordance with the above process even today.

    The modern chamois leather is the flesh splits of sheep or goat skins tanned by

    using colour fish oil7.The preservative properties of wood smoke also seem to

    have been noticed in the pre-historic times and these properties were made use of

    in making leather. Skins smeared with grease would have been smoked over wood

    fire, which helped the fat to penetrate the leather7.

    From the use of tree barks, some seeds, herbs, lime and oil to tan skin and

    hide, the use of several chemicals can be understood clearly and elaborately. The

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    time taken to tan a skin and hide has been shortened. The work done manually for

    centuries is being done now with sophisticated machines.

    Moreover, the army used the leather for making huge drums, which in

    Tamil is called Murasu. The ancient Tamilians were well-versed in music and

    they utilized many musical instruments of drum types for which they used well-

    processed and good quality leather8.

    The following figure shows the Location of Tanneries in various places of

    India along with Boundaries and Rivers:

    Figure 3.1

    Location of Tanneries in India

    Source: http://time.dufe.edu.cn/wencong/clusterstudy/n3edc3069b856c.pdf


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    3.3 Status of Leather Industry

    Leather tanning is one of the traditional industries in many developing

    countries. It is estimated that currently about 15 million tons of hides and skins is

    processed annually in the world per year. In a greater part of the developing

    countries, the leather industry is distinguished by small units with their distinctive

    problems of underutilization of process capacity, seasonal operations and unskilled

    workmanship. The manufacture of leather is one of the oldest and predominant

    technological professions in India. Man worked with hides and skins to make the

    earliest form of clothing. For this purpose, he had to face the challenges of the

    destructive forces of nature. With the setting of the European colonies in India,

    this industry became more organised, especially to meet the defence requirements

    of the British Empire. Till the beginning of the 19th

    Century, leather and allied

    industries in India formed one of the main activities of the