how to make leather backpack？
Many people may be very curious, counter to sell tens of thousands of dollars a luxury bag, in the end is how to do it? Not all models of the package can be sold into the counter. Normally, it takes a year and a half to draw a good drawing from the designer to the finished product. High-level will be repeated discussions, in the end which a more moving people, can sell well. In general, can enter the counter sale style, are fully recognized.
Well, let us work together to unveil the mystery of luxury bags, to understand its production process it.
The first step: drawing design. This is the designer of the things, drawing the more detailed, do the package closer to the original intention of the designer. This figure is the classic design of the MARISA.
Step 2: Select the skin sample. This is no doubt that a good bag naturally have the highest quality leather-like, preferably a whole piece of skin, so the package out of a more perfect. Even the thickness of the leather, have to take the vernier caliper to the amount of the how to make leather backpack： best not even a millimeter difference.
The third step: cut the leather-like. According to the drawings will produce a lot of cardboard, and do the same clothes. Do a bag of cardboard card needs, the average down to more than 200 sheets.
The fourth step: the skin of the stitching assembly. Handmade, need to use a lot of tools, such as professional leather glue and special sewing. This step requires the technical level of the producer, because a good bag can not be light-looking, but also durable. Some packages with more than ten years will not be bad, which need to test the craftsmanship of the producers.
how to make leather backpack：Background information:
Advanced customization is exotic, according to legend the mid-19th century, a man named Worth of the British, founded in Paris, a high-level customization store, when the hands of 20 employees to help him complete the amount of customization to the customer. "Only one, only for a guest service", because of this, advanced customization is equivalent to "noble status" symbol.
Now, the world's top custom brands are concentrated in Paris. In the advanced customization circle there is a requirement, must be done twice a year release, and each set of pieces to 35 sets. There is also a production time, a dress to spend at least 100-400 hours or more can be called advanced customization. From the price that is quite high in Europe and the United States, these consumers, advanced customization of consumer costs may vary from more than 20 million to millions of dollars.
how to make leather backpack：Leather material method
Leather, made from treated animal skins, is tanned to render it supple and non-perishable. Most leather is made of cowhide. Sheepskin, goatskin and pig skin are also important sources of leather. A small number of leather with buffalo, horses, alligators, sharks and deer skin. Cattle and horses and other large animal skin is often called the animal skin; hair with animal skin or animal skins often referred to as fur.
Leather is used to make shoes, also used to make suitcases, gloves, belts and other items. Some animal skins or skins are more suitable for the manufacture of a particular item. The main purpose of the particular leather species is given in the attached table.
Animal skin and skins divided into three layers - (1) the skin, called the epidermis; (2) the middle cortex, called the dermis; (3) the internal cortex, including fat with meat. Leather from the middle of the cortex, the main component of this part of the cortex fibrin, called collagen. The upper part of the cortex with a unique criss-cross pattern, called the texture; lower part called the dermis.
Leather production is divided into three steps. The first step is to prepare the raw skins to remove all the hair, epidermis and inner cortex. The second step is tanning leather, the middle cortex into leather. The third step is the final appearance of the leather by dyeing and other processes.
how to make leather backpack：Prepare the raw skins
Most of the raw materials in the tanning process have been processed before, the usual practice is to soak raw material skin in the brine (salt water solution). Preserving preserves the skin until it is tanned.
The tannery can use any of several methods to remove the hair, the skin, and the inner skin. This paper explores the usual methods of making leather.
First, soak raw material with cold water, remove dirt, salt and other impurities after salt residue. Next, the raw skins were placed in a solution of water, lime and sodium sulfide to loosen the hair roots and the epidermis. At the same time, gently stir the raw material skin, so that the epidermis and fat-free meat separation.
After soaking the lime water, the raw material skin is scraped off by the machine to remove all the hair and meat, leaving only the fiber portion of the raw material skin. The raw skins are then soaked with a solution containing a debinding agent such as ammonium sulfate and an enzyme to make the raw skins soft. After thorough cleaning, the raw material skin can be sent to tanning.
Commercial tannery is mainly used in two ways: chrome tanning (a mineral tanning method) and vegetable tanning. At present most of the leather with chrome tanning. Chrome tanning has largely replaced long, time consuming vegetable tanning. Vegetable tanning is now mainly used in the production of soles, belts and suitcase leather.
First, the raw skins were placed in a solution containing sulfuric acid and salt for a few hours. After the solution is completely penetrated into the raw material skin, chromium sulfate is added. And then slowly adding sodium bicarbonate, reducing the acidity of the solution, so that the solution of chromium and collagen chemical reaction, tanning raw material skin. After tanning raw material skin generally need to pile up overnight, and then remove the excess moisture.
The raw material into the tannic acid contained in a large tank immersion. Tannic acid is a plant-derived substance that acts in conjunction with collagen to produce leather. For commercial purposes, most tannins are extracted from the woody layer or bark of trees such as bark and oak.
The raw material skin from one cylinder to another cylinder, the tannic acid solution used to gradually strengthen. Usually need to use tannic acid solution soak for several weeks. After rinsing, leather was impregnated with natural fat and then dried.
Other tanning methods
Another method of making leather is called nitro, which involves tanning with a solution containing alum. Sometimes with tanning agents further processing of chrome tanned leather, leather to achieve the desired results. This processing method is called retanning. For example, re-tanning with a zirconium salt or formaldehyde can produce a white leather.
Oil tanning used in the manufacture of oil tanned leather. Oil tanned leather raw materials for the predecessor of the antelope, gazelle is a European native of an animal, similar to goats. But now the raw materials for oil tanning leather sheep skin in general. In the process of oil tanning, crushing to remove hair raw material skin, forcing the skin of most of the grease. And then hit and pinch, while cod liver oil and other marine biological oil. Finally, heating, decomposition of oil, leather, sand paper with a little friction will become dry. The leather produced in this way has a very strong suction.
Dyeing and final process dyeing
Prior to dyeing, the machine is usually used to cut leather into the desired thickness of the finished product, which is then placed in a barrel for dyeing. After dyeing, most will use natural oils and fats for further processing of leather, in order to complement the loss of processing oil. And finally dried. It is common practice to attach the leather to metal racks or to metal or glass trays and send them to the oven for drying. In the vacuum drying process, the leather on the sealed space, and discharge the air inside. As the pressure decreases, the moisture in the leather evaporates.
In the final process, the first leather to re-wet. And then coated with one or more protective materials such as wax, oil, cotton, casein-shellac pigments and various synthetic resins.
After the protective material is applied, it is usually also necessary to glaze the leather, which involves pressing the leather through a smooth steel or glass tube.
Soft lamb leather in the final process, the need to wrap the paper with a roller friction leather close to the inner side of the cortex, so that leather hair appears fine.