LEATHER PROCESSING TO MANUFACTURING PROPERTIES ARE MENTION IN THIS PPT

1. LEATHER
PROCESSING AND
PRODUCT
MANUFACTURING

2. Outline
 Introduction
 Production of leather
◦ Preparatory stages
◦ Tanning
◦ Crusting
 Forms of leather
 Types of leather
 Leather Products
 Environmental impact
 References

3. Leather is a durable and flexible
material created by the tanning of
animal rawhide and skin, often
cattle hide. It can be produced
through manufacturing processes
ranging from cottage industry to
heavy industry.
INTRODUCTION

4. Predominantly, most of the manufacturing units for
leather goods are located in cities like Kolkata,
Chennai, Mumbai, Kanpur, Bangalore and
Pondicherry. Kanpur is popularly known as the
“Leather City of the World”.
Kanpur leather traders Export leather goods in
large volumes throughout the world. These massive
amounts of leather products are shipped to New
Delhi and other major cities in India by the Kanpur
leather traders. From these places, they are exported
to other nations of the world.
Kanpur leather traders are involved in
manufacturing, exporting, and supplying of all types
of finished leather products.
Sourcing Hubs

5. Leather has been a luxury material for a long time and
there are many leather products, which people use in
their daily life.
Here is the list of Leather goods
 Belt
 Wallet
 Portfolio case
 Pet accessories
 Mobile case
 Ladies Handbag
 Watch Bands
 Men & Women Accessories
 Footwear
 Camera and Guitar straps
And much more…

6. PRODUCTION OF LEATHER
The leather manufacturing process is
divided into three fundamental sub-
processes:
 Preparatory stages
 Tanning
 Crusting

7. Preparatory stage:
In the preparatory stages the raw hide/skin is
cleaned and sterilized, under this process all the
unwanted matter like Flesh and blood stains are
removed.
Preparatory stages may includes :
 Soaking : under which the raw hide is washed
and is put in water temporarily.
 Unhairing : Just includes removal of hair
 Splitting : It includes cutting the raw hide into
many pieces of horizontal layers.

8.  Degreasing : Under this, non-chemically most
of the fats and oil are removed.
 Bleaching : Chemical modification of dark
pigments and stains to yield lighter colored raw
hide.
 Saline treatment : under this, all the harmful
bacterias are neutralized with the help of salt
solution.

9. Tanning:
Tanning is the process that converts the raw hide
into more stable form.
 In this process the proteins and fibers of the raw
hide is reacted with certain chemicals(Ex.
Chromium, formic acid) which changes the
property of the materials and makes it more stable
for the longer usability
 In this process leather is treated with chromium
which tanns the leather and change the color to
Light Blue for this the product is commercial
called “Wet Blue”.
 Tanning increases the hydrothermal stability

10. Crusting:
Crusting is the process by which the hide/skin is
thinned, retanned, lubricated, soften and
simultaneously coloured by the use of chemical.
The precautions which are to be taken by
crusting are as below :
 Amount of chemicals used
 Temperature & Pressure
 pH i.e. Maintain between 4.5 to 6.5
 Drying : The leather is dried to various moisture
levels
 Removal of moisture i.e. 40% to 55% water is
squeezed out of leather

11. For some leathers, a surface coating is
applied
Surface coating is one of the most important
process which includes the final toning of the
finished leather.
It includes treatments like;
 Oiling
 Brushing
 Buffing : It is the mechanical rubbing of the
final leather with soft material which
smoothens the surfaces.
 Polishing
 Ironing : it is done to remove the wrinkles.

12. Forms of Leather
Several tanning processes transform hides and
skins into leather:
 Vegetable-tanned leather is tanned using
tannins and other ingredients found in
different vegetable matter, such as tree bark
prepared in bark mills, wood, leaves, fruits
and roots and other similar sources. It is
supple and brown in color, with the exact
shade depending on the mix of chemicals
and the color of the skin. It is the only form
of leather suitable for use in leather carving
or stamping.

13.  Chrome-tanned leather is tanned using
chromium sulphate and other salts of
chromium. It is more flexible and pliable
than vegetable-tanned leather and does not
discolor or lose shape as drastically in water
as vegetable-tanned.

14. Types of leather
 Full-grain leather refers to the leather which has not
had the upper “top grain” and “split” layers separated.
 Top-grain leather is the second highest quality and has
had the “split” layers separated away, making it thinner
and more pliable than full grain.

15. Corrected-grain leather :-is this leather had an
artificial grain applied to its surface.
• Split leather:- is leather created from the fibrous
part of the hide left once the top-grain of the
rawhide has been separated from the hide.

16. Types of leather

17. Leather used in specialty products,
such as briefcases, wallets, and luggage
 Belting leather is a full-grain leather that was originally
used in driving pulley belts and other machinery. It is
found on the surface of briefcases, portfolios, and wallets,
and can be identified by its thick, firm feel and smooth
finish. Belting leather is generally a heavy-weight of full-
grain .

18.  Bycast leather is a split leather with a layer of polyurethane
applied to the surface and then embossed. Bycast was
originally made for the shoe industry and it was also adopted
by the furniture industry. shoe industry and it was also adopted
by the furniture industry.
• Napa leather is chrome-tanned and is soft and supple. It is
commonly found in wallets, toiletry kits, and other personal
leather goods.

19. Leather Products
Product group Description
Handbags Handbags with or without shoulder strap
Pocket or small leather goods Wallet, purses, key pouches, credit-card cases,
pen cases and other small articles
Travel goods Suitcases, casual travel bags, beauty cases, sports bags
and other travel articles
Stationary articles and special Writing pads, book covers, camera
cases cases, spectacles cases, jewel cases,
mobile phone holsters etc.
Military equipment Various holsters for fire arms
Belts Women's and Men's belts
Watch straps Watch straps made of leather and synthetics
Sports articles Balls for football

20. Environmental impact
 Addition to the environmental impact of
leather, the production processes have a high
environmental impact, most notably due to:
 The heavy use of chemicals in the tanning
process (e.g. chromium, formic acid,
mercury and solvents etc.)
 Air pollution due to the transformation
process (hydrogen sulphide during dehairing
and ammonia during deliming, solvent
vapours)

21. GOVERNMENT REGULATION
Globalization of the Indian economy is a major objective of the
Government. It has been appreciated that given the right type of
policy support and framework, India would be able to
substantially augment her exports. The basic thrust of Indian
economic policy in the recent years has been to integrate the
Indian economy with the global economy and expose the Indian
manufacturers to the global market and competition.
 ILDP- Indian Leather Development Programme –The Euro
223.15 Million scheme was undertaken during the Ninth Five
Year Plan (1996-2000) and is still being implemented during
the Eleventh Five Year Plan ( 2007-2012).
 Tannery Modernization Scheme –
This was launched under ILDP in 2000. The objective was to support
existing tanneries for undertaking modernization programe for
positive environmental impact, becoming competitive, effecting better
capacity utilization, achieving productivity gains and reducing
wastage.

22.  NLDP - National Leather Development Programe –
The Joint Programe of Government of India and UNDP with
a total outlay of Euro 19.11 Million ( with Euro 11.7 Million
from UNDP and the rest by Indian Government) was drawn
up for the integrated development of leather and leather
products sector within the country
 Leather Technology Mission –
The Government of India launched the four year mission in
January 1995 aimed at spreading the awareness of wide
variety of technology in the leather sector primarily
focusing the tanneries. The program coordinated by Council
of Scientific and Industrial Research with its constituent
organization, Central Leather Research Institute covered
172 projects in 16 States.

23. REFERENCES:
 Introduction to the principles of leather
Manufacture
 By-S. S. Dutta, 4th edition, I.L.T.A., Calcutta
 Theory and practice of leather manufacture
 By- K. T. Sarkar, Macmillan Indian Press,
Madras.
 Google Images
 https://www.slideshare.net/radhe5559/leather
-technology
 https://www.slideshare.net/adeleagatha/list-
of-leather-goods