Learn about the process of leather manufacturing in a precise manner

1. PROCESS OF LEATHER
MANUFACTURING
Presented by
k.Magesh
II year mechanical engineering

2. What is Leather?
1. Leather is a durable , flexible product made by the tanning of
animal raw hide and skin, usually obtained from cattle .

3. Day to day applications of leather
• Leather is universally used all over the world.

4. FORMS OF LEATHER
1. Vegetable tanned leather
2. Chrome tanned leather
3. Aldehyde tanned leather
4. Brain tanned leather
5. Rose tanned leather
6. Synthetic tanned leather
7. Alum tanned leather

5. LEATHER MANUFACTURING:
1. Preparatory stage,
2. Tanning ,
3. Crusting.

7. PREPARATORY STAGE:
• Here the skin is prepared for tanning.
• Unwanted particles are removed

8. Preparatory stages include
• Preservation
• Soaking
• Liming
• Unhairing
• Fleshing
• Splitting
Soaking Process

9. • Reliming
• Deliming
• Bating
• Frizzing
• Bleaching
• Pickling
• Depickling

10. WHAT IS TANNING?
• Conversion of animal proteins from raw skin into stable material which will not putrefy is
called as Tanning

11. Process of Tanning
• After pickling, the pH of the
hide is about 2.8-3.2.
• During Tanning, penetration
of tanning agent (eg. Cr),
into the material is checked
often.
• After tanning pH changes to
3.8 to 4.2.

12. CRUSTING:
Crusting is when the hide/skin is thinned, retanned and lubricated.
It includes 5 main processes- Sammying
- Splitting
-Neutralization
-Stuffing
-Drying & Conditioning

13. ADDitional process
• Suitable only for some Leathers.
• Process includes
Oiling
Spraying
Polishing
Surface coating

14. Finished products

15. SOCIAL IMPACTS
 The heavy use of polluting chemicals in the
tanning process leads to chemical pollution.
 Air pollution due to the transformation process
(Hydrogen sulphide during dehairing and
ammonia during Deliming, solvent vapours).

16. People’s ignorance
• People , in spite of the available alternatives prefer leather by
products only because of its durability
• They do not usually think of the ecosystem.

17. Suitable alternatives
• Due to some obstacles created by vegetarians, suitable
alternatives are preferred
• Microfibers are preferred for usage.

18. List of 5 eco friendly alternatives
• Microfibers
• Cork
• Glazed cotton
• Jute
• paper

19. This is how microfibers work

20. THANKING YOU