| After Fleshing comes "Scouring." This 30-45 minute | | | | Drycleaning must then take place over the following |
| segment of the process uses surfactants at high | | | | 4-24 hours. Either a white spirit (high boiling petroleum |
| temperatures and takes care of removing dirt and | | | | fraction) or perchloroehtylene is used to remove any |
| lanolin (grease) from the wool. | | | | natural fat or grease that remains in the skins. |
| "Pickling" of the sheepskin then takes about 16 hours. | | | | |
| Before the sheepskin can be tanned, they have to | | | | Following final removal of the pelt grease, "Pelt Dyeing" |
| be pickled. Pickling means soaking the skins in a | | | | or "Syntanning" comes next. Back in the paddle (the |
| solution of acid and salt. Adding salt prevents any | | | | soaking vessel), the pelts are dyed in cooler |
| potential swelling of the skins because of the acid. It's | | | | temperature dyes (less than 30 degrees Celsius). This |
| important to lower the internal pH of the skins to | | | | minimizes staining of the wool. After the pelt dyeing is |
| somewhere between 2.8-3.0, which will allow the | | | | completed, syntanning involves using synthetic tanning |
| tanning agent to properly penetrate the skin. | | | | agents to make the pelts added fullness and firmness. |
| | | | | Finally, the skins are dried once more. |
| Classic Series: UGG Classic Tall Metallic | | | | |
| | | | | Step 2. Finishing |
| The 16-hour "Tanning" step involves using chromium | | | | |
| salts which form cross-links with the collagen, thereby | | | | After the lengthy tanning process is complete, the final |
| helping to stabilize the skin structure and preventing | | | | finishing is done so the skins may be used to make |
| putrefaction or rotting. This step is performed at room | | | | ugg boots. |
| temperature, around 25 degrees Celsius, and around a | | | | |
| pH of 2.5-3.0. Once the tanning agent (the chromium) | | | | The skins must be conditioned to approximately 20% |
| penetrates the skin, the process is stopped, and the | | | | moisture content. Staking is the process by which the |
| chrome is fixed to the collagen by raisng the pH to 3.6 | | | | skins are softened and stretched, and a "nappy" |
| using sodium bicarbonate and heating the skins to | | | | surface is added to the pelt. |
| between 35-40 degrees Celsius. In doing so, the | | | | |
| shrinkage temperature of the skin is raised to | | | | Final "Combing," "Ironing" and "Clipping" then takes place |
| anywhere between 60-100 degrees Celsius. | | | | to remove any tangles, burrs, or grass seeds that may |
| | | | | be remaining in the wool. The wool is straightened |
| Next comes "Wool Dyeing" or "Fatliquoring." This takes | | | | using an iron to remove the natural crimp. Lastly, a |
| anywhere from 3-4 hours to complete. After the skin | | | | clipping machine creates a uniform wool pile at a |
| is tanned, the wool may be dyed any of a variety of | | | | desired length (usually 12-15 mm). |
| colors. Wool dyeing needs to be done at about pH | | | | |
| 4.5-6 and at 60-65 degrees Celsius. Special "pelt | | | | Step 3. Manufacturing |
| reserve agents" must be added to keep the wool dye | | | | |
| from staining the pelt. Once the dye is stable, the pH is | | | | A "clicking press" is used to cut individual panels from |
| lowered to about 4.0 to fix the dyes to the wool, and | | | | the skins. After being cut to the right size, the panels |
| fatliquor is added to the solution. Fatliquors are part | | | | are then sewn together using special industrial sewing |
| of leather manufacturing that help to lubricate the | | | | machines. The soles are then glued to the boot upper, |
| collagen fiber and allow them to move flexibly and | | | | and, finally, the Ugg Boots are ready for you to |
| freely once the skin is dried. This is what makes the | | | | purchase. |
| leather feel soft. | | | | |
| | | | | The whole process can guarantee you to wear |
| Drying of the skins then takes 4-24 hours. Forced air | | | | genuine and comfortable ugg boots. Your feet bear |
| dryers are used with the skins stretched across a | | | | too much through your whole days' work, and you |
| frame. Drying occurs at 50-80 degrees Celsius. | | | | know they deserve better treatment. |
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