>>> Hi Roger, so I use the Hydrator-3.3 and Fatliquor-5.0, then Vachetta-2.8. Right?
Right!
If we assume that the original fatliquor diminishes by 1% per year, 12 years would be 12 %.
How long from the time it was fatliquored up till the leather is transform into this lovely bag is still an unknown.
The only possible way to ascertain or determine the existing remaining percentage of original fatliquor is only my a leather moisture meter or equivalent. This useful instrument will take the guesswork out making our effort more scientific. If you have such an instrument that can read material moisture level it will help. Measurement should be taken from various areas of the leather and keep a note prior to the actual cleaning processes. Stains areas may produce a false reading, as the meter cannot differentiate between contamination and the original fatliquor.
Know the product characteristic and its function before using it and any clarification are welcome.
The multi functional abilities include:
a) To check for surface tension for an even appearance free from blotchiness prior to fatliquor replenishing.
b) To plumps, relaxes and separates crushed, shrunk and stick together fibrils for manipulating away-unwanted creases and wrinkles.
c) To clean the leather of structural foreign contamination, the plump and limp leather is squeeze with towel laid between the leather and a smooth spatula or equivalent.
d) To rectify alkaline overexposure areas by facilitating colloidal water movement to redistribute the leather constituents from surrounding areas.
e) To activate the dormant dyestuff within the leather structure for color refreshing.
f) To facilitates colloidal water movement within the inter-fibrillary spaces for wicking foreign soiling particulates to resurface.
g) To stabilize, pH balance and charge the protein fiber below its iso-electric point (pI) ionic positive to hydrogen bond with the ionic negative fatliquor more effectively.
A - Hydrator-3.3 for General Cleaning Purposes:
A1 – Leather is first brush with Brush-1 and erase with Eraser-4 of surface soiling. This process will lightens up the leather as well. Any stiff spot my be protein related and has the tendency to coagulate and will need the used of a bamboo skewers to removed any stiff soiling as well.
A2 – Hydrator-3.3 is either sprayed direct or transfer to foam brush or Brush-1 whichever suites best and Eraser-4 is also being used during this wet process along with bamboo skewers to loosen up stiff penetrated soiling if any. Cotton terry towel is used to extract suspended soiling until the towel shows clean. Covering the leather with towel through and squeezed with the smooth edge of the brush is also a common practice. Keeping the leather saturated all the time helps released below surface soiling as well. All these while keep an eye on what the terry cotton have pick-up and the deeper it need to get the harder the leather need to be squeezed. When towel shows clean with each application and extraction and the leather appearance have taken an even appearance even though it still remains saturated to a degree says 25% moisture level from meter reading.
B – Hydrator-3.3 for pH Balancing:
B1 – Immediately following from the last cleaning cycle the leather is tactile-feel tested for possible denaturing.
Any sign of tackiness, stickiness or extreme cases of sliminess with our bare hand indicates alkaline overexposure. A more scientific measurement is with a pH meter that has a flat glass probe. A healthy reading should read between 3 and 4 from the meter. Otherwise the leather has to be pH balanced with Acidifier-2.0 until closed to pH 3 and 4. Simply spray Acidifier-2.0 and let it work by itself with Brush-1 agitation and towel extraction before a fresh application until it neutralized to its pH neutral or iso-electric point or pI. Without such meter we have to feel the transformation into a healthy squeaky feel and the neutralization is completed.
C – Hydrator-3.3 for returning back to Structural Dimension:
C1 - Any unwanted creases and wrinkles are manipulated away in this sequence of process. The leather could be keep hydrated for up to 72hrs with control evaporation in order to work out extreme cases.
D – Fatliquor-5.0 for Leather Suppleness when Dry from Cracking:
D1 Fatliquor-5.0 begins when the moisture contents is between 14% - 25%. Fatliquor-5.0 is applied accordingly and Brush-1 helps to even out as well. With each drying cycle up to 14% - 25% mark new application begins. During the final application again up to this 14% - 25% mark the leather is gently massaged and flexed evenly before allowing going too stiff. Note that at 14% fatliquor moisture level is already dry.
Leather Approximate Quantity or Percentage of Fatliquor:
The quantities of fatliquor (fat and oil) contents retained in the leather after an universal tannery fatliquoring process may varies up to 14% depending on the leather types and it usage. This percentage drops as the fat and oil content diminishes or leaches through ageing, water, heat or chemical overexposure.
Leather rejuvenating or fatliquor replenishing is base on weight of the leather in relation to the percentage of remaining fatliquor. A simple calculation of percentage of fatliquor topping up requirement would be as follows:
If the weight of the leather in question is 100gm and fatliquor (fat and oil) content meter reading is less than 1%.
By applying 80gm of Fatliquor-5.0 to it will deliver an end result incremental of 13.3% fatliquor when dry as the 66.6% water contents evaporates.
In the leather rejuvenating Hydrator-3.3 > Fatliquor-5.0 > Hydrator-3.3 system, Hydrator-3.3 plays an important role by relaxing, opening up the inter-fibrillary spaces, facilitating and redistributing colloidal water movement, protonating and doing all the pre-conditioning work prior to fatliquoring including cleaning up any excess surface remnants to have a sticky-free surface. In practice the ratio for Hydrator-3.3 is 2 to 1 of Fatliquor-5.0.
It works out to be approximately 160gm of Hydrator-3.3 plus 80gm of Fatliquor-5.0 to replenish a 100gm dry leather from less than 1% back to the original tannery up to 14% fatliquor content.
Recommended that pictures are taken for reference and larger size pictures for clarity is preferred
Roger Koh
Leather Care Consultant
[email protected]