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用户:God910403/crocodile leather

Crocodile Leather


Since ancient times, humans have taken pride in crafting leather goods from ferocious animals. Dating back to antiquity, during the ancient Chinese Shang and Zhou dynasties, people made drums with crocodile skin, known as "tuo drums" or '鼍鼓'. To this day, crocodile leather has a rich history, with ancient Egypt using Nile crocodiles to make mummies and deifying crocodiles as gods. In ancient Rome, generals crafted armor from crocodile skin, now preserved in the British Museum. Modern people primarily use crocodile leather for leather goods, renowned for its durability. Each scale has cartilage or bone, effectively resisting piercing and slashing.

Introduction to Crocodiles 编辑

Crocodiles are typical large carnivorous reptiles belonging to the class Reptilia of the phylum Chordata. They are distributed in tropical to subtropical regions and prefer habitats with abundant water, such as rivers, lakes, and swamps, or moist areas in hills. There are currently 25 species of crocodiles. Crocodiles have a lifespan of approximately 70 to 100 years and are ectothermic animals. They are apex predators in the food chain, with a long growth cycle. When kept in captivity, they require space for basking in the sun. The stomach of an adult crocodile is about the size of a soccer ball.

varieties of crocodile leather 编辑

Crocodylus porosus:Mainly inhabits estuaries, also known as saltwater crocodiles due to their preference for brackish water environments. Growth cycle: Approximately 12 to 14 years to reach maturity.

alligator: Mainly found in North America. Growth cycle: Approximately 10 to 15 years to reach maturity.

Crocodylus niloticus: Native to Africa, especially in the Nile Basin. Growth cycle: Approximately 12 to 14 years to reach maturity.

Crocodylus novaeguineae: Native to New Guinea. Growth cycle: Approximately 12 to 15 years to reach maturity.

Crocodylus siamensis: Indigenous to Southeast Asia. Growth cycle: Approximately 8 to 10 years to reach maturity.

Crocodylus caiman: Primarily inhabits Central and South America. Growth cycle: Approximately 8 to 10 years to reach maturity.

Crocodile Leather Production Process 编辑

  • Skinning: Crocodile skin is peeled from the crocodile's body, typically using a method that leaves the belly intact while opening the back. The retention rate of the leather can vary depending on the technique and skill level, with rates as high as 90% for belly-intact skinning and only 70% for back-intact skinning.
  • Drying: During the curing process, a layer of salt is evenly spread on the surface of the leather to prevent hardening and absorb surface moisture, which helps with initial dehydration.
  • Scaling: Professional tools such as skin scrapers or sandpaper are used to remove scales from the surface of the crocodile leather. If scales are not removed, they can negatively affect the texture and quality of the leather during the tanning process.
  • Fleshing and Degreasing: The leather is soaked in a degreasing solution, and a fleshing knife is used to remove fats, flesh fibers, and other impurities from the crocodile leather.
  • Salting: The leather is soaked in a saltwater solution to prevent decay and aid preservation.
  • Desalting: The crocodile skin is removed from the saltwater and excess salt is washed away with plenty of fresh water.
  • Thinning: The crocodile skin is thinned to approximately 1.2 to 1.6mm thickness to facilitate better penetration of solvents in subsequent processes.
  • Acidification: When preparing leather blanks, the crocodile skin is soaked in an acidic solution to lower the pH level. This helps remove impurities such as fats and proteins from the leather and promotes the penetration of tanning agents.
  • Tanning: This process can be divided into vegetable tanning and chrome tanning, with each factory using different tanning formulas.
  • Stretching: Also known as staking, the crocodile skin is stretched and secured with clamps or nails to prevent shrinkage during the tanning process, which can reach up to 40% in area and cause damage to the surface texture.
  • Dyeing: The crocodile leather is immersed in dye to achieve the desired color. The dye penetrates the fiber layer of the leather during soaking, and the concentration and immersion time of the dye need to be carefully controlled to ensure uniformity and depth of color.
  • Fixation: Fixation ensures the permanence of the dyeing effect and prevents fading. Typically, the leather is immersed in a special fixing agent after dyeing to better fix the dye in the leather.
  • Finishing Treatment: Processes such as waxing, polishing, and oiling are applied to the leather. A classic example is using agate stones to physically polish the leather to a glossy finish.
  • Crocodile Leather Finishing: Sorting, inspection, grading, and packaging of the completed crocodile leather.

Crocodile Leather Tanning Techniques Introduction 编辑

  • glazzed crocodile leather techniques: Agate Stone Polishing Technique, Matte Finish Technique, Wax Polishing Technique, Nappa Technique, Himalayan Technique, Indigo Dyeing Technique, Chromium-Free Tanning Technique, Sanding Technique, Film Coating Technique, Multi-color Dyeing Technique, etc.
  • glazzed crocodile leather techniques: One of the typical finishing methods for crocodile leather, imparting a smooth, elegant, and gem-like luster to the surface. After dyeing, a protein-based polishing agent, such as casein, is applied to the crocodile leather surface in a dust-free environment, and agate stones are used to apply strong friction to produce a mirror-like shine.
  • Matte Finish Technique: Developed through improvements in farming and tanning techniques. During dyeing, oil is applied to the leather to make it soft and provide moderate tension. During finishing, the leather surface is polished with felt using a polishing machine, giving it a soft luster. Because of its soft and low-sheen surface, it can be widely used from dressy styles to casual styles. Additionally, the surface treatment allows you to enjoy the feel of use over time, such as increasing color depth and gradually increasing luster.
  • Wax Polishing Technique: After dyeing in a drum, wax is applied to cover the surface of the leather. Similar to matte finishing, felt polishing provides a moderate luster. Crocodile leather undergoes changes with use over time, appearing wild and attractively casual.
  • Nappa Technique: A soft finish developed specifically for clothing and gloves. A large amount of softening agent is added during crocodile leather tanning, but with the increase in quantity, weight also increases proportionally. "making you want to touch the fluffy feeling," and has achieved the ultimate Nappa finish.
  • Indigo Dyeing Technique: Indigo dyeing is an ancient dyeing method using a plant called indigo. Typically, leather is batch dyed with acid dyes on a drum. On the other hand, indigo dyeing is handcrafted using natural indigo dye. The color changes after the indigo dye comes into contact with air, but it is not a single dyeing process; rather, the color depth deepens with repeated dyeing. research utilizes crocodile leather to express traditional craftsmanship, successfully reviving the natural, most beautiful colors that are on the verge of extinction.
  • Chromium-Free Tanning Technique: Chromium tanning is an excellent tanning method but is not suitable for producing light or soft colors as chromium imparts a bluish tint to the leather. has developed a chromium-free tanning agent to produce high-quality chromium-free leather. "Chromium-free tanning" gives the leather a semi-transparent appearance, without the natural dark patterns of crocodile leather, presenting it in white. Another method is vegetable tanning, which utilizes tannins from plants to process crocodile leather, resulting in a lighter skin color.
  • Nubuck crocodile leather craft: The surface of crocodile leather is sanded with sandpaper to remove surface imperfections, requiring skilled craftsmen to operate to avoid damaging the leather. The crocodile leather surface presents a rugged style, with a coarse sand-like texture when touched.
  • Film Coating Technique: A thin film is heated and pressed onto the surface of crocodile leather.
  • Multi-color Dyeing Technique: Produced using spraying or brush coloring, dyeing, hand painting, scraper, etc. Initially, a base color is applied as an undercoat, followed by the use of color stacking to create beautiful colors.


References 编辑

References


external link 编辑

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