Leather industry is one of the largest and oldest sectors of the manufacturing industry. This industry produces a wide range of products starting from leather bags, leather jackets, leather garments, leather shoes etc. in large numbers. Many countries around the globe are using leather products as one of their biggest trade items for export. The reason being the high rate of consumption in the day to day life of people.
The manufacture of leather is a process of several steps and involves the expertise of a number of people, which is why leather products are termed not just as a purchase but an investment.
Read this blog and know the steps of leather manufacturing.
The very step before starting the process of manufacturing is the collection of raw materials. The industry drives this raw material from the waste products of the food industry. The process done is specifically meat processing.
This collected raw material then goes through several steps to bring out the final manufactured product.
Three sub processes namely preparatory stages, tanning and crusting are performed on the raw animal skin.
But before these steps , manufacturers tend to perform some other steps as well to preserve these raw materials from damage before the actual process starts. Methods of preservation include salting, chilling, freezing and the use of biocides.
Once the leather is preserved, it is gone through further processes to prepare it for the process of tanning. This pre-tanning process includes the following step.
1. Soaking: To hydrate the cured leather and clean any salt or dirt from it, leather is soaked in water for several hours and days so that it can reabsorb water and be hydrated enough.
2. Painting And Liming: Painting is a method by which wool can be removed from sheepskins using a sulphide based mixture. Conventionally, the hides or skins are treated with sodium sulphide and hydrated lime. This leaves the characteristic pattern of the grain surface in the leather.
3. Deliming: The previous processes leave the leather swelled up and its ph. is also increased. The process of deliming gradually neutralizes the alkali in the pelt, avoiding rapid changes in pH which could lead to distortion or disruption of the tissues.
4. Pickling: Weak acid and salt solutions are used to bring the pelt to the weakly acid state required for most tanning processes. Stronger pickling solutions are used to preserve pelts so that they can be stored or transported in a stable form over periods of several months.
After all the above processes are done, the skins are finally ready to be tanned. Tanning is the process that converts these treated skins into leather. This is made possible by the use of chemicals, usually termed as tannins. These chemicals penetrate into the skin and produce a utilizable material resistant to microbial attack.
The materials used for the process of tanning are of different types including mineral tannings using chromium tanning salts, vegetable tannins and more recently used Aldehyde and oil tannings by glutaraldehyde.
A splitting machine slices thicker leather into two layers. The layer without a grain surface can be turned into suede or have an artificial grain surface applied.
The leather manufacturer begins neutralizing the acids left behind from tanning. It removes residual chemicals and prepares the leather for further processing and finishing.
The classic and stylish colors we see in leather are the outcome of the process of dyeing. Some leathers are only surface dyed, while others need completely penetrated dyeing, as is the case with suede leathers.
Now the dyed leather is taken under the process of drying. Leather is normally dried to 10-20% water content. The final binding of chemicals is encouraged by the drying process. The resultant curst material is resistant to microbial attack and contains all the leathering properties desired of leather and is ready for finishing.
Now that the leather is done being treated enough, it is finally ready for the one last finishing touch. The finishing chemical used is very carefully designed to play its role. It helps in hiding defects, adds to the leather beauty and properties and provides fashion effects.
The end of the finishing steps also marks the end of the process of leather manufacturing. Now this finished products is sent to the product manufacturers who with their craftsmanship turn it into leather shoes, garments, bags and other beautiful products like we have been doing at The Leather Craft for the last 20 years.
Leather manufacturing is one of the most detailed processes of the manufacturing industries. It is a process that dates back to several years. The steps performed are done with care and experience and are the presentation of craftsmanship. This is the reason that the final product is so refined and beautiful that it is no less than a lifelong investment.