Imperial Suede and Restoration- Facts and historical information about the leather jacket. (edited by Brian Monk) content from www.madehow

History

 

Leather, a natural fabric made from tanned animal skins, has been used as garments since the beginning of human existence. Prehistoric people covered themselves with animal skins  for warmth and to absorb the magical powers they believed the skins held.  Phoenician sailors often brought brightly embroidered leather garments from  the countries they visited such as Babylonia.   Leather footwear was  found in the  Egyptian tombs of  pharaohs.
Roman Soldiers invaded the lands of northern Europe and discovered Teutonic nomads wearing leather garments as protection against the harsh climate.   When these soldiers returned to Rome with leather pants, city officials, who wore togas tried to ban their use. They could not stop the oncoming trend.   Romans were soon using leather for shoes and tunics as well as for breastplates and shields.  The first recorded tanning guild was started in the Roman Empire.

During the Middle Ages, the Moors introduced  Europe to softer type of leather known as Cordovan,which they hides from goats.  During the  Renaissance, tanners' guilds were organized all over Europe. .Mayan, Incan, Aztec, American Indians began to tan hides from cattle, deer, and buffalo.  These were fabricated into garments and foot gear.  Mocassins came to be recognized a basic item for the Indians.

In the Stone Age, clothing were tied  together with leather straps that had been threaded through holes punched in the hide with crude tools made from stone. The hides were stiff and did not last long before decomposition made them unusable.  Later, people discovered how make hides soft by agitating them with animal fats.  They used stones to scrape animal pieces from the hides.  Preservation methods were invented as the early techniques of dyeing and curing skins evolved.

Various preservation methods have evolved over time.   Skins have been hung over fires, treated with salt, urine, even animal feces.  They have been beaten, and dragged over sharp sticks.  Indians and Eskimos have tried to soften leather by chewing the skins to remove hair and leftover pieces of flesh.  For other cultures, the talc or flour was usedto replace the natural oils.  Fragrances were used to cover up some of the odors of leather.

Leather was a valuable  commodity on the open market.   Tanning animal hides was hard and dirty work.  It was foul smelling.  Most tanning facilities were operated outside of town.

Ancient Hebrews used Oak Bark in their tanning process. The American Indians oils from fish  in the same regard. American colonists used plants in their early tanning processes.  During the 19th century, machines were developed to perform these processes using chromium salts.   THis reduced the processing time from weeks or months to a matter of hours.

Raw Materials Used For Garments

Cowhide are the hides most commonly used to make leather jackets. As soon as the skin is removed from the animal at the meat processing plant, it is refrigerated and salted.  It  then goes to a tannery. The skins receive a series of processes that will preserve and soften the hides.   Cowhides are byproducts from the beef industry.  Pigskins come from the Pork induustry.  While lamb is popular amongst consumers, not as many animal are harvested for food items.  This makes lamb skins a more luxurious fabric.

Threads, fabrics used for linings, knits for cuffs or bands, fasteners are usually supplied by outside sources.

-Back-

 

The Preparation Process

Trimming and cleaning

 

The skins are graded according to size, thickness and weight.  Remaining proteins must be removed in order to prevent growth of bacteria. The skins are soaked in revolving drums filled with water, bactericides, and detergents.   Lime is added to skins which aids in hair removal.  Extra hair is removed by a scudding machine using dull blades.

Another round of washing neutralizes the lime chemicals.  Then, the hides are soaked in an acid solution and then bated, an enzyme treatment to further remove the skins' collagen. Salt and sulfuric acid is added, known as pickling

Tanning

There are three types of tanning. Vegetable tanning processes require a lot of time having the skins soaked in stronger and stronger tannic acids for at least 12 hours for some lamb skins and up to several weeks for other hides. for several weeks.

Mineral tanning much faster, but canalter the color of the leather. For this method, the skins are placed in alum salt-filled drums fitted with paddles that provide a constant agitating motion.

Oil tanning, is the one that mimics ancient methods. Here, fish oils are directly onto skins. sprayed onto the skins.

Washing and drying

After tanning, they are washed once again and wrung out thoroughly. Then the skins are split under a planing knife.  The skins are cut to a uniform thickness  and then go to drying tunnels.  The hides are stretched over frames for drying.  This step is to prevent shrinkage.  In order to combat the stiffness that drying produces, the hides are sprayed with water and soap and allowed to hang for drying.
The skins are then conditioned and placed in machines designed to manipulate the leather so that the fibers become loosened and  flexible. In the final drying period, the hides are hung in vacuum-drying cabinets.

When the skins are thoroughly dried, they are buffed with revolving steel cylinders covered with abrasive paper. Suede finishes are produced by passing the hides under high-speed emery wheels to make the nap stand up. Colors are added at this point using various, glazes, dyes, and lacquers are applied. Once the finishes are cured, they can be sent to the garment factory.

The Manufacturing Process

 

Garments may be produced in two fashions.  A single tailor may complete all steps involved in designing,  cutting patterns, and assembly.  This is an art form that is sought out by the wealthy.  As sewing machines developed, most garments are mass produced in assembly line fashion.

 

 

 

Jacket design

 

Designers begin the process using computers to lay out patterns for jacket design.  The computer may aid in sizing to meet government regulations for proper height and weights.  There are uniform sizing that must be complied with.  Computer aided designs are made to accommodate a range of sizes. S,M,L,XL,XXL, etc... while maintaining the original design.

Cutting the patterns

The garment leather is placed on moving tables.  Regular textiles may be cut in layers, but leather is usually cut one skin at a time.  The pattern is placed on top of the leather.   Paper patterns may be pinned onto the leather and marked by hand with chalk.  Hand cutting is rapidly being replaced with automated systems operated by computers.  Leather fabrics are moved to cutting machines where they are fitted with either rotary blades or band-knives.  The latest systems use lasers to cut the seams.

Lining materials of the jacket is cut in the same manner, but are done in multiple layers.

 

 

Jacket assembly

The jacket is assembled varies from design to design.  Most garments follow the same steps.  The sides are first sewn to the back portion.  Then, the area under seams are stitched together and the sleeves are attached to the armholes. The attachment of finishing pieces such as collars, cuffs, buttonholes, buttons, zippers, and pockets varies according to the design of the jacket. Patch pockets are sewn onto the side pieces before they are stitched to the back portion, and side pockets are sewn in at the same time that the sides are attached to the back. Generally, lining material is installed to each piece before it is sewn onto the jacket.

In mass production, the pieces are moved along a highly sophisticated production line using computerized sewing equipment capable of sewing up to 8,000 stitches per minute.  Often, one sewing machine stitches a particular section of the jacket and then moves the garment to another sewing machine which performs the next step. After one machine stitches a cuff to the sleeve, the sleeve moves to another machine where it is attached to the jacket armhole, for example. 

A tandem sewing system calls for two or more machines to work on the same garment at the same time. Multiple steps are completed at the same time.  One machine may attaches buttons to the front of the jacket while another machine applies the collar.  Using multiple machines speeds up the assembly.

Each step, from setting thread and needle positions to aligning the fabric to extracting the sewed materials, is pre-programmed. Each sewing machine is equipped with under-bed trimming devices that automatically knot and cut threads after each seam is sewn. Excess threads are carried away to waste receptacles by streams of compressed air.

Operators oversee the work at each station  from a control panel. A stop-motion device allows the operator to halt production to make adjustments such as replacing broken threads or needles.

 

Molding and pressing

Pressing processes which use heat application, steaming, and blocking complete the transformation of the animal skins into a jacket.  Automated  Buck presses equipped with controls and gauges to regulate the amount of steam and pressure are used to give the jacket its distinctive dimensions, based on the style of the jacket. Curved blocks are placed around the collars and cuffs and then heat is applied for proper shaping. 

 

Final inspection

Each jacket is inspected by a person before it leaves the factory floor. The completed jackets are packaged in plastic bags, packed into cartons, and shipped to the retailer.  

 

Quality Control

The thoroughness of the tanning process is designed to produce skins that are supple and free of bacteria-causing proteins. Garment manufacturers inspect and grade each shipment of skins for marks, tears, stains, and imperfections.

Today's automated sewing systems are self-correcting. Sophisticated lubricating systems composed of pumps, reservoirs, fluidic controls, and electronic controls insure that the garments are manufactured at a consistent level of quality.  The final inspection ties the advances of automation to the human expectation of certain levels of quality.

Looking Ahead

Although the leather goods industry suffers slightly during times of recession, merchandisers may implement  discount strategies.  New technologies, such as laser cutting are improving accuracy and increasing the rate of production.  Leather jackets may become increasingly affordable and long lasting when properly maintained.  Production costs for the professional leather cleaner are increasing, especially in the transportation area.   It is important to realize that owning a leather garment requires specific care that can be provided by the leather cleaner.  Leather will continue to be fashionable and long lasting.  The traditional nature of the leather jacket and its exceptional endurance, will keep the leather jacket viable.