togwt
The Old Grey Whistle Test
uncandid said:
Dr. Woo said:And here I am to do the same thing, 4 months later.
If your not satified with any of the hypothesis offered why not do your own research and advise the forum of its outcome?
Leather Fatliquoring – A Point of Contention!
- Thread starter Roger Koh
- Start date
If your not satified with any of the hypothesis offered why not do your own research and advise the forum of its outcome?
I have been reading all of TOWGT's writings on this site and must say I agree with him! I have found that automotive leather I have simply kept clean with soap (Woolite) and water has lasted much longer than leather treated with leather conditioners!
I have tried them all (Zaino, Lexol, Mothers, Leatherique, etc.). All I ever got was a slippery, sticky mess that attracted dirt. Nothing else!
I have bought into the fact automotive leather is coated with urethane and nothing can penetrate it. These conditioners simply sit on top of the leather until they evaporate making the inside of your windows smeary and almost impossible to clean!
The leather in my Ferrari 360 is ten years old, has never been treated with a conditioner, and looks like new!
The leather in my NSX and C6 Corvette has been treated regularly with conditioners and looks worn and dirty!
No more leather conditioners for me guys!
I have tried them all (Zaino, Lexol, Mothers, Leatherique, etc.). All I ever got was a slippery, sticky mess that attracted dirt. Nothing else!
I have bought into the fact automotive leather is coated with urethane and nothing can penetrate it. These conditioners simply sit on top of the leather until they evaporate making the inside of your windows smeary and almost impossible to clean!
The leather in my Ferrari 360 is ten years old, has never been treated with a conditioner, and looks like new!
The leather in my NSX and C6 Corvette has been treated regularly with conditioners and looks worn and dirty!
No more leather conditioners for me guys!
David Fermani
Forza Auto Salon
Rob4092xx said:
Hey - I know you from the Corvette Forum!
lostdaytomorrow
New member
dfoxengr said:
I would like to hear more about this! I know scottwax has used it for a very long time successfully. I can't imagine it causing any serious issues being cut 20:1 though.
lostdaytomorrow said:
A little understanding about the chemistry of leather cleaning, do a little testing and draw your own conclusion from, should set your taught straight.
Leather is amphoteric, at the molecular level, any pH value solution above its iso-electric point will cause the protein fiber to shift ionic negative and any solution below its iso-electric point (the pH neutral of leather is between 3 and 5 is also the iso-electric point of the leather) will strengthen the leather ionic positive.
Leather is not all 100% protein fiber; it has its other constituents especially the tanning agents that convert the perishable protein fiber to non-perishable leather. Tanning alone does not impart enough softness to the leather. The suppleness and strength of the leather depends on the fatliquor (ionic charged fat, oil and water). The tanning agent and the fatliquor are hydrogen bonded to the protein fiber with forces of ionic attraction similar to a magnet – like poles repel and unlike poles attracts. When the ionic charges between the protein fiber and the fatliquor weaken, the leather begins to denature with signs of dryness, shrinkage, stiffness that leads to cracks.
The problem with leather is that the protein fiber is amphoteric and should remain ionic positive (+ve), while the other chemistry remains unchanged ionic negative (-ve). It is this shifting of the protein fiber to ionic negative (-ve) with alkaline solution that is the cause of the problem with leather.
An acidic cleaning solution, therefore charges the protein fiber more ionic positive (+ve), thus strengthen the leather chemistry integrity of the leather with the other ionic (-ve) tanning agent and fatliquor.
An alkaline cleaning solution (“woollike”), shift the protein fiber ionic (-ve), thus repels the hydrogen bond between the protein fiber and especially the ionic negative (-ve) fatliquor (as seen in the picture below where rainwater alone at almost pH 7 will cause the protein fiber to shift ionic negative (-ve) thus shrink and stiffen the leather).
In most pigmented auto leathers, which often is non-absorbent we are concern about the stitching holes and the perforated holes or when micro-crazing develops, there is when the leather structure are exposed to absorption of cleaning solution.
If rainwater with a pH value close to 7 can do damages to leathers, any cleaning solution higher than that of water will eventually damage the leather especially those above the pH 8 range (woollike at 1: 20 dilution reads from pH 8 to 9).
#1 Water (pH 6 to 7) Damaged Areas
#2 Close-up view of the leather Shrinkage that cause the Stiffness.
Leather rejuvenating technique . . .
#1 Fatliquor-5.0 is applied to the cleaned surface and after Hydrator-3.3
#2 A paper rag/towel is used as a reservoir to contain the fatliquor and is covered with a plastic cling wrapper to control evaporation
What do you think?
Alkaline cleaning solution damages leather.
Acidic cleaning solution strengthens the chemistry integrity of leather.
True or False, you vote?
Roger Koh
[email protected]
togwt
The Old Grey Whistle Test
I’m not sure wither to admire your tenacity or wonder at your reluctance to admit your hypothasis may be incorrect.
Everyone I’ve talked with, including the vendor (LTT) on this thread, the Leather Research Laboratory and the American Leather Chemists Association (a professional body you yourself suggested I contact for confirmation of the validity of post tanning fat liquoring) and they are all in agreement that it is not needed nor possible
[A little understanding about the chemistry of leather cleaning, do a little testing and draw your own conclusion from, should set your taught (sic) straight] - Roger Koh
Urethane doesn’t require conditioning; always keep in mind that you’re dealing with the finished coating on the leather and not with the leather hide itself. The pH value of leather is purely academic and of little, if any value with regard to the care of finished leather.
[Alkaline cleaning solution damages leather.
Acidic cleaning solution strengthens the chemistry integrity of leather.
True or False, you vote?] - Roger Koh
Please expand on the principle of ' Acidic cleaning solution strengthens the chemistry integrity of leather'
Everyone I’ve talked with, including the vendor (LTT) on this thread, the Leather Research Laboratory and the American Leather Chemists Association (a professional body you yourself suggested I contact for confirmation of the validity of post tanning fat liquoring) and they are all in agreement that it is not needed nor possible
[A little understanding about the chemistry of leather cleaning, do a little testing and draw your own conclusion from, should set your taught (sic) straight] - Roger Koh
Urethane doesn’t require conditioning; always keep in mind that you’re dealing with the finished coating on the leather and not with the leather hide itself. The pH value of leather is purely academic and of little, if any value with regard to the care of finished leather.
[Alkaline cleaning solution damages leather.
Acidic cleaning solution strengthens the chemistry integrity of leather.
True or False, you vote?] - Roger Koh
Please expand on the principle of ' Acidic cleaning solution strengthens the chemistry integrity of leather'
togwt
The Old Grey Whistle Test
dfoxengr said:
Woolite® has a number of issues that do not lend to long term quality care of interior car parts and components. Using a detergent that is meant to be flush rinsed (i.e. rinsed until it runs clear) in a situation where this is not possible, is not recommended as when it dries it will attract dirt and contribute to re-soiling, it will cause leather to shrink and harden .
These types of detergent soaps tend to be formulated with a sodium sulphate to enable foaming, this salt content may not be safe to use on leather upholstery, as this can compromise pigmented leather and / or its polyurethane covering. This product contains alkalis (sodium hydroxide), which forms a strong alkaline solution when dissolved in a solvent such as water to provide foaming, and a solvent (alcohol) as an aid to cleaning; these will further aggravate the drying out process due to its capillary action and their affinity with moisture.
It also contain optical brighteners (Stilbenes) which are dyes that absorb energy in the UV-B light spectrum thereby accelerating UV degradation when exposed to large amounts of UV light through a car window. They fade, degrade, and destroy fibres and also tend to dry out the upholstery
togwt
The Old Grey Whistle Test
Simply put the potential of hydrogen (pH) scale is a set of numbers between 0 and 14 where 0 (Hydrochloric acid) is the most acidic and 14 (Bleach or Lye) is the most alkaline (caustic) pH is a characteristic of water solutions only; without water, you cannot have a pH. The pH scale is logarithmic; for every integer that the scale decreases the material is 10 times more acidic.
An alkaline cleaner (hand soap has a pH of between 9.0 – 10.0) is used to clean most materials used in an automobile interior, including finished leather. Cleaning products use surfactants and other additives (such as water softeners) so its pH is not the only criteria used (i.e. a neutralized acid wheel cleaner has a pH of 7.0, so if pH is the only criteria it should be safe to use this product on anything as pH 7 (neutral)
Most foam cleaners are pH balanced, meaning they are base (Alkaline) chemical, buffer solutions are used as a means of keeping the pH at a nearly constant value. This is mostly marketing; a neutral pH 7 or balanced pH sounds 'safe' to the consumer.
http://www.autopia.org/forum/autopi...ues-select-car-care-products.html#post1489793
An alkaline cleaner (hand soap has a pH of between 9.0 – 10.0) is used to clean most materials used in an automobile interior, including finished leather. Cleaning products use surfactants and other additives (such as water softeners) so its pH is not the only criteria used (i.e. a neutralized acid wheel cleaner has a pH of 7.0, so if pH is the only criteria it should be safe to use this product on anything as pH 7 (neutral)
Most foam cleaners are pH balanced, meaning they are base (Alkaline) chemical, buffer solutions are used as a means of keeping the pH at a nearly constant value. This is mostly marketing; a neutral pH 7 or balanced pH sounds 'safe' to the consumer.
http://www.autopia.org/forum/autopi...ues-select-car-care-products.html#post1489793
togwt
The Old Grey Whistle Test
Alfisti said:
Most foam cleaners are pH balanced, meaning they are base (Alkaline) chemical, buffer solutions are used as a means of keeping the pH at a nearly constant value. This is mostly marketing; a neutral pH 7 or balanced pH sounds 'safe' to the consumer.
Simply stated the potential of hydrogen (pH) scale is a set of numbers between 0 and 14 where 0 (Hydrochloric acid) is the most acidic and 14 (Bleach or Lye) is the most alkaline (caustic) pH is a characteristic of water solutions only; without water, you cannot have a pH. The pH scale is logarithmic; for every integer that the scale decreases the material is 10 times more acidic.
An alkaline cleaner (hand soap has a pH of between 9.0 – 10.0) is used to clean most materials used in an automobile interior, including finished leather. Cleaning products use surfactants and other additives (such as water softeners) so its pH is not the only criteria used (i.e. a neutralized acid wheel cleaner has a pH of 7.0, so if pH is the only criteria it should be safe to use this product on anything as pH 7 (neutral)
See also - Using pH values to select car care products