Results 1 to 18 of 18

Thread: Vegetable-Tanned (Topcoated) - Problem chairs, vegetable tanned

  1. #1
    Join Date
    Aug 2008
    Posts
    661

    Default Vegetable-Tanned (Topcoated) - Problem chairs, vegetable tanned

    Roger, One of our technicians cleaned these 2 chairs. I believe they are vegetable tanned? Or a very light aniline tanned.
    they now look blotchy or spotted. What should we do to fix?

    #1
    Name:  100_1157.JPG
Views: 713
Size:  1.97 MB

    #2
    Name:  100_1158.JPG
Views: 456
Size:  3.13 MB

    #3
    Name:  100_1159.JPG
Views: 506
Size:  2.15 MB


    #4
    Name:  100_1161.JPG
Views: 399
Size:  2.38 MB
    Last edited by Administrator; 03-24-2014 at 03:17 PM. Reason: Numbering

  2. #2
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    >>> Roger, One of our technicians cleaned these 2 chairs. I believe they are vegetable tanned? Or a very light aniline tanned. They now look blotchy or spotted. What should we do to fix?

    These may be the resurface of penetrated stains that need re-clean with system products from this Kit V6.
    However, there may be a collection of unknown stain from various sources. It could be natural pigmentation or some sign of mold infestation.

    In most of these situation Vachetta-2.8 solves typical problem associated with light grease and browning, for some darkening grease may require Degreaser-2.2 > Acidifier-2.0 as the first step follows with Vachetta-2.8.

    Traditional system is by Degreaser-2.2 > Acidifier-2.0 follows with d’Tannin-3.5.

    The red arrow mark out stain could be protein based to produce a darker outer ring and may be done with d’Protein-10 follows with d’Tarnish-1.3 to deal with the rust component.

    The blue arrow could be a possible dye stain and such stain is deal with Prep-4.4 > Clean-3.8 > Rinse -3.0 spotting system.

    Name:  attachment copy.jpg
Views: 534
Size:  1.98 MB



    Name:  a207915142eea173f2b905_m.JPG
Views: 399
Size:  106.2 KB
    Leather Doctor Kit V6 – Vachetta Leather Grease/Ink/Dye/Browning Removal Kit
    Leather Doctor® Kit V6 is a combination problem solving kit that includes products from Kit V5.dr, Kit V5.ds and Kit V3. Common stains encounter in the course of vachetta leathers lifetime includes the darkening effect from neglected body oil, grease and sweat contact, the occasion ink and dye transfer, and the browning from liquid and sun tanning seasoning effect just like our skin. The protein leather fiber is an ionic positive (+ve) “amphoteric” material thus pH sensitive to influence by alkaline solution shifting ionic negative (-ve), even water with a pH of 7 often discolors or browns it. Its other non-amphoteric leather constituents like the tanning agent and the fatliquor remains ionic negative (-ve), hence just like a magnet – “like poles repel”, breaking of the hydrogen bond between them, the leather denatures and in extreme cases revert to rawhide. This adverse contamination is rectify by Degreaser-2.2 > Acidifier-2.0 system, both to simultaneously degrease and protonate the protein fiber ionic positive (+ve) to its pH chemistry integrity. Ballpoint, printing ink, dye transfer, gum, sticky substance and accumulated soiling will require the penetrating, lubricating and suspending power of Prep-4.4 follows with Clean-3.8 to remove the sticky residue and Rinse-3.0 to a healthy squeaky feel. Browning from liquid stain or sun tanning is eliminated or reduced by chemical reaction from Vachetta-2.8 when dry. The above describe the three common class of stain removal. Leather rejuvenating mandatory sequence follows to soften and strength the leather from stiffness that may leads to cracking when flexed. Among leather finishes type, vachetta leathers is the most fatliquor (fat, oil and water) thirsty and will require more fatliquor to soften it then chrome-tanned leathers. In order to lubricate each fibril within the leather structure behaving like millions of interconnecting hinges the fat and oil has to be hydrogen bonded to the fibrils. This is accomplished by preconditioning the leather structure with Hydrator-3.3 effectively prior to faliquor replenishing it with Fatliquor-5.0 in between drying cycle until fully saturated. Natural slow drying in between application produces softer leather. Protecting the leather with Protector-D reduces wear to the grain of the leather, conceal scuff with its healing properties that also allows transpiration to take place or breaths naturally. Note that the mentioned products suffix numbers denotes its pH value in this holistic approach to removing the common problems associated with vachetta, saddlery and veg-tan leathers.

  3. #3
    Join Date
    Aug 2008
    Posts
    661

    Default

    Roger,
    I applied Degrease 2.2 with a sponge and tried to apply as eavenly as possible. Allowed to dwell for about 5 minutes, then rinsed off with Acidifier 2.0 and extracted with dry towels. repeated the acidifier 3x allowed to dwell until almost dry about 15 to 20 minutes. Now misted on DTannin 3.5 and am allowing to dry overnight. I still see blotchyness so far. Hopefully they look good tomorrow.

  4. #4
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    Like to have pictures of your processes, how the leather response in terms of absorbency or saturation will determine its effectiveness, since most of these stain are penetrated, it will require them to wick to the surface especially the grease to be towel extracted or help with Eraser-4 as well.
    Last edited by Roger Koh; 03-25-2014 at 10:34 AM.

  5. #5
    Join Date
    Aug 2008
    Posts
    661

    Default

    Roger,
    I would help if you would describe procedure, not just products. Such as apply degrease 2.2 as evenly as possible with a sponge, agitate with aniline sponge. Allow to dwell for? Rinse with Acidifier, spray on and wipe off, etc...

    I got a good improvement on one chair and the other looks about the same.

    Name:  100_1168.JPG
Views: 499
Size:  2.14 MBName:  100_1197.JPG
Views: 408
Size:  1.99 MBName:  100_1200.JPG
Views: 396
Size:  2.05 MB

    Above pictures are of Acidifier and extracting with towels

  6. #6
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    >>> It would help if you would describe procedure, not just products. Such as apply Degrease 2.2 as evenly as possible with a sponge, agitate with aniline sponge. Allow dwelling for? Rinse with Acidifier, spray on and wipe off, etc...

    General instructions are found on the product label itself and from the on-line store as seen from this photo shot below. The user has to decide in this case Hydrator-3.3 what will be the intend purpose and apply accordingly.

    Specific instruction is why this forum becomes useful.

    Unique about this forum is every problem is shown with pictures so that problems have a specific reference.

    You have three pictures; there should be a picture reference to it and a brief description why you are showing it, so that help is more specific. Are the 3 pictures of the same chair or 3 different chairs?


    >>> I got a good improvement on one chair and the other looks about the same.


    If possible show chair that got the good improvement with a reference and show the others as well.

    Procedure varies according to severity, the one chair is just clean right and the others are under clean may have other more unknown stain. With good picture, I can help you identify it.

    Name:  Screen Shot 2014-03-26 at 11.23.48 AM.png
Views: 378
Size:  317.5 KB

    Roger Koh
    Leather Care Consultant
    www.LeatherDoctor.com

  7. #7
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    Vegetable-Tanned Leather Description:
    Vegetable-tanned leather is tanned using tannin and other ingredients found in different vegetable matter such as tree bark prepared in mills, wood, leaves, fruits and roots and other similar sources. It is a supple and brown in color with the exact shade depending on the mix of the chemicals and the color of the skin. It is the only form of leather suitable for use in leather carving or stamping. Vegetable-tanned leather is not stable in water, it tends to discolor, so if to soak and then dry it will shrink and become less supple and hard. In hot water, it will shrink drastically and partly gelatinize, becoming rigid and eventually brittle.

    This naked unfinished Vegetable-Tanned (V) Leather Problem Solving Guide is used as reference.

    Name:  Vegetable-Tanned (V).jpg
Views: 341
Size:  351.2 KB


    Roger Koh
    Leather Care Consultant
    www.LeatherDoctor.com

  8. #8
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    With reference to your three pictures from post #5, the uneven absorbency may suggest that this leather may have some clear finishing such as varieties of AnilineTop-21 applied impeding or obstructing ingress or access of solution from penetrating or reaching the penetrated stains. A more open grain leather will be easier for direct contact with the stain and the convenience of wicking them out to the surface.

    By removing the finishes if any will make penetrated stain removal easier.

    Stripper-2.3 may be tested on a hidden corner to reveal the original crust.

    AnilineTop-21 (4 version) is tested against the strip test back to match the original.

    Until the match is perfect, the stripping of the stain areas commence, stain removed, leather rejuvenated and refinish is a viable solution for consideration.

    Otherwise all products used have to be soak in with a darkening effect and allows sufficient dwell time for it to break through the finishes if any.

    Further questions are welcome whichever route is most convenience.


    Tips:
    When dealing with vegetable-tanned leathers all solution applied has to have an even appearance, at least feathering out without streaks or drips in order to produce the best result in most situation.



    Roger Koh
    Leather Care Consultant
    www.LeatherDoctor.com
    Last edited by Roger Koh; 03-26-2014 at 12:26 PM.

  9. #9
    Join Date
    Aug 2008
    Posts
    661

    Default

    Roger, One chair looks much better but still has some blotchiness. The other only had some improvement. I had to send them back. They will send them back again when they go out of town.

    Name:  100_1280.JPG
Views: 476
Size:  2.01 MB
    This chair still has problems

    Name:  100_1282.JPG
Views: 337
Size:  2.38 MB
    Closeup

    Name:  100_1283.JPG
Views: 316
Size:  2.07 MB
    This chair almost acceptable

    Name:  100_1284.JPG
Views: 333
Size:  2.42 MB
    Close up

  10. #10
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    >>> This chair still has problems

    Do a test on one of the darkest spot and see how it response.

    Need to be aware that old leather do show natural pigmentation just like our skin and may not be a soiling issue.

    In such cases the only approach is a micro touch-up - practice by universal tannery where not every skin is perfect thus lower the grade with artificial coloring.

    Coloring camouflage is the last resort, stripping of the topcoat to allow direct access to the leather itself is the first approach as discussed.
    Last edited by Roger Koh; 03-29-2014 at 01:45 PM.

  11. #11
    Join Date
    Aug 2008
    Posts
    661

    Default

    Roger, We picked up chairs again, and ready to proceed. By the way the discolorations (blotchiness) that we couldn't remove previously are now gone and chairs look very uniform. However; one chair looks more soiled and or possibly browned out? on arms and seat area.
    Name:  100_2403.JPG
Views: 403
Size:  3.18 MB

    We now have your Vachetta cleaner and would like to know how to proceed?

  12. #12
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    >>> We now have your Vachetta cleaner and would like to know how to proceed?

    Vachetta-2.8 works by oxidation-reduction reaction and results are revealed when leather is completely dry.
    Suggest approach is by direct spraying and working with a white terry towel to pick up any surface soiling and changing sides of the towel when soiling is apparent.
    To work out for deeper even appearance penetration horsehair Brush-1 is used and for better control of product 3” foam brush may be used. The final appearance should look evenly saturated to avoid any blotchiness when dry.

    Recommend that you take pictures when evenly wet for reference to compare when dry.

  13. #13
    Join Date
    Aug 2008
    Posts
    661

    Default

    Name:  100_2447.JPG
Views: 313
Size:  2.43 MB

    Chair after Vachetta applied multiple times and tried to even out.

  14. #14
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    Like to see when completely dry.

  15. #15
    Join Date
    Aug 2008
    Posts
    661

    Default

    Name:  100_2463.JPG
Views: 381
Size:  2.42 MBName:  100_2471.JPG
Views: 322
Size:  1.84 MB
    I don't think there was any improvement, possibly the arms look a little darker/ browned out appearance?

    Name:  100_2464.JPG
Views: 265
Size:  1.98 MB
    Right arm dark browning condition

    Name:  100_2466.JPG
Views: 295
Size:  2.31 MB
    L arm same condition

    Name:  100_2465.JPG
Views: 308
Size:  2.23 MB
    Seat about the same?
    Attached Images Attached Images     

  16. #16
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    >>> I don't think there was any improvement, possibly the arms look a little darker/ browned out appearance?


    Tips:

    You may try indirect stretching those dark areas placing a waxed paper and using a smooth edge of spoon or saucer to lighten it up a little and gently work with Eraser-4.
    (Try it on the stain spot as well).

    Please let me know if it works before I give you another tip?

    Vachetta-2.8 is design for unfinished leathers, perhaps this is an Aniline leather with a finish that has poor response.

  17. #17
    Join Date
    Aug 2008
    Posts
    661

    Default

    Stretching may have had a slight improvement. But I still don't think the chairs look any different than before we tried to clean them originally

  18. #18
    Join Date
    Feb 2007
    Location
    Greater Vancouver, Canada.
    Posts
    4,669

    Default

    Degreaser-2.2 > Rinse-3.0 system will help remove the hand oil or grease that is the cause of the darkening effect.

    Try the "reverse transferring" effect with stretchable towel for the soiling particulates to wick through rather than still remaining on the leather surface.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •