Tanning is the process of treating skins to produce leather. Before the Industrial Revolution, tanning was a particularly smelly "odoriferous trade". Often dung and urine were used in the process; it was common for children to be employed as dung gatherers and for there to be ' piss-pots' on street corners to collect urine for use in tanneries.[ 1] Before tanning, the skins are unhaired, degreased, desalted and soaked in water over a period of 6 hours to 2 days. Historically this process was considered a noxious or "odoriferous trade" and relegated to the outskirts of town. In soaking, the hides are soaked in clean water to remove the salt left over from curing and increase the moisture so that the hide or skin can be further treated. Once applied, the tanning waters develop over a couple of hours to leave your skin with a beautiful golden tint. As they are transparent, waters do not stain bedding or clothes making them the perfect tanning products to wear either overnight or throughout the day before a big event. Which are the best tanning waters? Following the adoption in medicine of soaking gut sutures in a chromium (III) solution after 1840, it was discovered that this method could also be used with leather and thus was adopted by tanners. Preparation

William Richardson of Great Ayton started tanning local sheepskins; in 1701 he moved to Whitby extending his tanning business to include seal-skins. The expanding business and moved to Newcastle in 1780 eventually to become famous as Edward and James Richardson Ltd. Achieve a happy, hydrated glow with the Isle of Paradise Self-Tanning Water. So lightweight on the skin and enriched with skin-loving ingredients including coconut, chia seed and avocado oils, the mist creates the most natural-looking tan with minimal effort. Simply spritz liberally over the skin and buff into the skin using a mitt and leave to develop. Collagen is characterized by a high content of glycine, proline, and hydroxyproline, usually in the repeat -gly-pro-hypro-gly-. These residues give rise to collagen's helical structure. Collagen's high content of hydroxyproline allows for significant cross-linking by hydrogen bonding within the helical structure. Ionized carboxyl groups (RCO2−) are formed by hydrolysis of the collagen by the action of hydroxide. This conversion occurs during the liming process, before introduction of the tanning agent (chromium salts). The ionized carboxyl groups coordinate as ligands to the chromium(III) centers of the oxo-hydroxide clusters.The Leather Act of 1563 included a law that leather intended for the outer soles of shoes should be soaked for at least 12 months and other shoe leather for 9 months. As an alternative to tanning, hides can be dried to produce rawhide rather than leather. Associated processes How to use: Apply directly to exfoliated, clean, dry skin. Pump foam directly onto your Revolution Tanning Mitt. Apply in a sweeping motion over legs, arms & body. Use your remaining tan on the mitt for face, elbows & knees. Allow tan to develop for 4 hours then rinse with warm water. Store at room temperature. Keep out of direct sunlight and below 25 degrees.

Focus on one body part at a time, gently massaging the tanning water into your skin before moving on to the next area.

History

Subsequent to application of the chromium agent, the bath is treated with sodium bicarbonate to increase the pH to 4.0–4.3, which induces cross-linking between the chromium and the collagen. The pH increase is normally accompanied by a gradual temperature increase up to 40 °C. Chromium's ability to form such stable bridged bonds explains why it is considered one of the most efficient tanning compounds. Chromium-tanned leather can contain between 4 and 5% of chromium. This efficiency is characterized by its increased hydrothermal stability of the skin, and its resistance to shrinkage in heated water. Vegetable tanning