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zealtee
04-07-2015, 06:06 AM
Dear all,

I recently bought a leather bag from Morocco, Fez, off the streets, and am pretty sure it is genuine leather.

When I bought it, it is of a light brownish-orange color, and I thought of darkening it (also as per advice by the shopkeeper) with extra virgin olive oil.

The leather did darken but black spots appeared all over the bag.


#1
4922


#2
4923


#3
4924


#4
4925

I applied 2 more layers of olive oil to see if it would go away, but it didnt.

Brushing slightly diluted lemon juice on it did not seem to help too.

Would really appreciate if someone could enlighten me on the identity of the black spots and educate me on removing them.

Thank you!

Roger Koh
04-07-2015, 10:06 AM
>>> Would really appreciate if someone could enlighten me on the identity of the black spots and educate me on removing them.

When stains are moving like in Picture #1.

It will continue to move or stop and result as stain.

Or

Continue moving until the staining concentration is spend – thus the stain intensity reduced.

Or

The stain is reverse transfer with a stretchable paper towel off the surface.


It also looks like the dyestuff becomes unstable and starts migrating.


Tips:
If the dyestuff is unstable – using Acidifier-2.0 with a pH value of 2.0 will protonate the leather protein fiber making the ionic attraction between the dyestuff and the protein fiber stronger from easily breaking hydrogen bond.

Blotchiness most probably from the becoming unstable dyestuff may be rectify with Hydrator-3.3 to reduce uneven surface tension and to redistribute the leather constituents and wicking off with reverse transfer technique off the surface.

These are two produce process to see how the leather response before other available options when we begin to understand how the stains in pictures #3 and #4 derived from. One possibility could be scars from fungus infestation that makes these spots more absorbent taking up excessive oil as the result. Excessive oils are removed with Degreaser-2.2 > Acidifier-2.0 system.


Roger Koh
Leather Care Consultant / Practitioner
[email protected]

zealtee
04-10-2015, 03:34 AM
Thanks Roger for your advice!

This does seem like alot of work though, and a little bit uncertain how its going to turn out (in terms of cleaning) as I have no idea where did the black dots come from (stains, scars, iron dusts etc.) since it came with the bag and appeared after conditioning.

I've been thinking of a redye to mask/cover up the bag and I would like to seek your advice if it would work, and if conditioning it after the dye dries would cause the black dots to resurface. (Im using Renapur Leather Balsam)

Also, how much would you reckon it will cost to redye the bag myself?

Thank you.

Roger Koh
04-10-2015, 12:25 PM
>>> This does seem like alot of work though, and a little bit uncertain how its going to turn out (in terms of cleaning) as I have no idea where did the black dots come from (stains, scars, iron dusts etc.) since it came with the bag and appeared after conditioning.

You may be right about the turn out, especially working with unknown stains, you may have to try each stain type class out with this:

Aniline (A.fs) Full Sauvage Leather Problem Solving Guide.
4936


>>> I've been thinking of a redye.

When using a transparent dyestuff there are two choices – the “staining” type like Aniline-21 or the coating type like Aniline-76. Using ‘transparent’ dyestuff recommendation is by camouflaging the darkest stain to retain the beauty of depth. In this case ‘coating’ dyestuff stand a better chance to coats the surface of the leather. If this is the choice then the extra virgin oil needs to be degreased by Degreaser-2.2 > Acidifier-2.0 system. Virgin oils of any grade are stuffing oils and are unstable as it migrates and will pose a problem to any coating sitting on top. Without the olive oil either of the transparent dyestuff system will have been a better solution to darken the appearance..


>>> to mask/cover up the bag.

There are 4 choice of medium when comes to dye or color leather.
1 – Transparent Staining Dyestuff like Aniline-21 system
2 – Transparent Coating Dyestuff like Aniline-76 system
3 – Translucent Hybrid dyestuff like Antique-27 system
4 – Opaque Coloring system like Micro-54 system


>>> and I would like to seek your advice if it would work,

It will only work if the olive oil is first removed; otherwise it is not comparable with the above 4 most recent waterbased system.


>>> and if conditioning it after the dye dries would cause the black dots to resurface.

The black dots are beneath or camouflage with dyestuff or coloring and should not reappear with a matching systm topcoat.


>>> (Im using Renapur Leather Balsam)

Not familiar with the above-mentioned products.


>>> Also, how much would you reckon it will cost to redye the bag myself?

It depends what system you are interested an example would be using this
Leather DoctorŽ Kit-A7.cl system.
http://www.leatherdoctor.com/kit-a7-cl-aniline-leather-dye-refinishing-kit/

4935

zealtee
04-10-2015, 05:37 PM
Thanks Roger for your reply.

I've read up on redying leather online and found that I have to use a preparer/deglazer prior to dyeing. Just curious, does a preparer remove the oil as well or just the finish of the leather?

Roger Koh
04-11-2015, 10:24 AM
>>> Just curious, does a preparer remove the oil as well or just the finish of the leather?

Finishes is on the surface.
Penetrated oil in this case is below surface and continues moving to the surface.

Deglazer or Stripper-2.3 removes surface finishes and oils.

Below penetrated oil is removed with Degreaser-2.2 > Acidifier-2.0 > Hydrator-3.3 system.

You may consider sending the bag to me for professional services.

Roger Koh
Leather Care Consultant / Practitioner.