prasentation

1. Leather
Technology
Submitted To : Presented By :
Dr. Brishti Mitra Ankit Sonker
Head Of Department CSJMA14001390376
Chemical Engineering Chemical Engineering

2. OVERVIEW
• Introduction
• Production of leather
– Preparatory Stages
– Tanning
– Crusting
• Leather Surface Coating
• Types of leather
• Schematic Diagram Of Types Of Leather
• Uses of Leather
• Leather Product
• Environmental impact
• References

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

4. PRODUCTION OF LEATHER
• The leather manufacturing process is divided into
three parts :
1. Preparatory Stages
2. Tanning
3. Crusting

5. PREPARATORY STAGES
• 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 include :
1. Soaking
2. Un-hairing
3. Splitting
4. Degreasing
5. Bleaching
6. Saline treatment

6. TANNING
• Tanning is the process that converts the raw hide into
more stable forms.
• In this process the proteins and fibers of the raw hide
is reacted with certain chemicals e.g. chromium,
formic acid which changes the property of the
materials and make it more stable for the longer
usability.
• Treating with chromium turns the leather and change
the colour to light blue for this the product is
commercially “wet blue”.
• Tanning process increases the hydrothermal stability.

7. CRUSTING
• Crusting is the process by which the hide/skin is
thinned, re-tanned, lubricated, soften and
simultaneously coloured by the use of chemical.
• The precaution which are to be taken are as below :
1. Amount of chemical used
2. Temperature & Pressure
3. pH maintain between 4.5 to 6.5
4. Drying

8. LEATHER SURFACE COATING
• It includes treatments like :
1. Oiling
2. Brushing
3. Buffing
4. Polishing
5. Ironing

9. TYPES OF LEATHER
• Full grain leather
• Top grain leather

10. • Corrected grain leather
• Split leather

11. SCHEMATIC DIAGRAM OF
TYPES OF LEATHER

12. USES OF LEATHER
• Leather is use for various purposes :
– Bookbinding
– Leather Wallpaper
– Furniture Covering
– Car Sheet Cover
– Clothing

13. LEATHER PRODUCTS
• Handbags - handbags with or without shoulder strap
• Pocket goods - wallet, purses, key pouches, credit
card cases, pen cases
• Travel goods - suitcases, casual travel bags, beauty
cases, sports bags and other travel articles
• Belt - woman and man belts
• Watch straps - watch straps made of leather and
synthesis
• Sport articles - ball for football, rugby

14. ENVIRONMENTAL IMPACT
• Addition to the environmental impact of leather, the
production processes have a high environmental
impact.
• The heavy use of chemicals in the tanning process
e.g. chromium, formic acid , mercury and solvent etc.
• Air pollution due to the transformation process
(hydrogen sulfide during de-hairing and ammonia
during de-liming, solvent vapors)

15. REFERENCES
• S.S. Dutta, “Introduction to the principles of Leather
Manufacture” , 4th edition, I.L.T.A., Calcutta
• K.T. Sarkar, “Theory and Practice of Leather
Manufacture”, Macmillan Indian Press, Madras
• Google Images

16. THANK YOU
HOPE YOU
ENJOYED !