Product Overview
Suede Fatliquor 5.0 by Leather Doctor is a pH 5.0 softening conditioner of fat, oil, and water to restore the suede's original softness, strength, and flexibility.
- Prevents suede from drying, stiffening, or tearing
- Maintains a soft, luxurious feel
- Improves tensile strength and durability
- Ensures suede remains pliable without feeling greasy
- Essential for long-term suede preservation
Fatliquor plays a crucial role in the leather’s conditioning process by replenishing the fat and oil content that keeps leather supple and prevents stiffness or cracking. When applied, the water-encased fat and oil molecules penetrate the leather fibers. As the water gradually wicks away during the drying process, the fat and oil remain, hydrogen bond with the fibers and creating a breathable structure that enhances the leather’s elasticity and durability. Fatliquor 5.0 is essential for maintaining and restoring vachetta, aniline, nubuck, suede, and other leathers, preventing them from becoming brittle over time. Proper fatliquoring ensures that leather retains its tensile strength, resists breakage, and continues to feel soft and luxurious.
Almost all leathers including nubuck, suede, hair-on, sheepskin, and shearling finished goods will need periodic conditioning to replenish their diminishing fat and oil content to regain their softness and flexibility. This is attained in the fatliquoring process by introducing fat and oil into the leather so that the fibers individually are uniformly coated. The percentage of fat liquor on the weight of leather is quite small 7-14%. The technique of distributing this small amount of fat and oil throughout the leather will affect its subsequent useful life. It is necessary to emulsify the fat and oil to allow a small amount to be spread uniformly over a large surface of the leather fibers. In an emulsion with water, the fat and oil are dispersed in microscopically small droplets, giving it a white, milky appearance, just like milk is an example of a natural emulsion. The fat and oil droplets must remain as a milky emulsion until they penetrate the leather, not separate as large drops or as a layer of oil, which could not penetrate the leather fiber and would only give a greasy surface layer. Fatliquor, the lifeblood of leather makes important improvements to its properties; they play a fundamental role in governing the softness, pliability, stretch, or hand; the ability to resist water; the resistance to abrasion, and the smoothness of the grain. The effect obtained will depend upon the type of leather; the quantity of fat and oil; how it is applied and whether it is all on the surface or has penetrated the internal structure.
If the fiber structure is tightly woven smooth or finished, the leather will be firmer, making it more difficult for the fat liquor to penetrate the fibers uniformly. Chrome-tanned leather with diminishing fat liquor dries out firm, stiff, and hard. However, spreading a relatively small amount of fat liquor over the fibers, readily reduces the hardness, improving the stiffness for its softness and stretchability. Vegetable-tanned leather with diminishing fat liquor is less hard than chrome leather; however, more fat liquor must be added to vegetable-tanned leather rather than chrome leather to obtain the same softness or stretchability. Normally the leather becomes softer and stretchier as more fat liquor is used however, excessive amounts of fat and oil may give an undesirable, greasy feel, or may interfere with redyeing and refinishing.
Fatliquor promotes the lubricating of adjacent fibers rubbing against each other or reduces the adhesion between them. Fatliquor is applied to the wet leather to prevent the fibrils from sticking together during drying. Fatliquor gross penetration into the inter-fiber spaces the fat and oil molecules are hydrogen bond to the molecular leather fibrils. Fatliquor is ionic negative (-ve) charged which gives a much firmer attachment to the ionic positive (+ve) charged leather fibril, with less migration during drying, thus less fiber collapse during drying, and hence a fuller leather.
Fatliquor is applied to the damp leather, ideally when the leather fibers are fully hydrated but little free water exists in the spaces between the fibers. Fatliquoring to completely dried leather fibers results in rapid absorption, often resulting in dark-colored, greasy patches, moreover, the resultant leather is not so soft, resilient, or full as when fat liquor is applied to the damp, hydrated fiber. This is because without or insufficient fat liquor and when leather dries, the fibers shrink due to loss of water and come closer together, when cohesive forces come into play, cross-linking the fibril or fiber structure, making it firmer, harder, and less flexible or "crusty". These forces may be of the nature of Van der Waals forces or dipole or hydrogen bond forces, which would be much stronger. The degree of crustiness will depend upon the tanning type, being less with vegetable tanning, which may account for many of the hide's dipole forces, and more with the chrome tannages, where the effect is less.
- Concentrate is mixed well before adding distilled water 1: 5 before use.
- Apply and redistribute with appropriate brushes or pads until structure is saturated.
- Repeat each cycle water contents evaporate leaving behind only the fat and oil content.
- Allow natural drying for extra softness.
- The desired suppleness is further staked and massaged, accordingly with a little wet back with Hydrator 3.3 until dry.
- What is Fatliquor?
- How does Fatliquor work?
- Why does Fatliquor Work?
- When does Fatliquor Work?
- What is the Purpose of using Fatliquor?
- What is the Purpose of Fatliquor?
- What is the original percentage of leather fat and content from the tannery?
- How does the Fatliquor content of Fat and Oil Diminish?
- How to determine the Percentage of Fatliquor required by the leather?
- How to calculate the percentage of fat liquor required?
- Why is Hydrator 3.3 used before Fatliquor 5.0?
- What is the ratio of usage between Hydrator 3.3 and Fatliquor 5.0?
- Fatliquor 5.0 conditioner is a micro-emulsion of fat, oil, and water for rejuvenating, restoring, and softening suede to impart their original suppleness and protect them from dry rotting and stiffness.
- Concentrate when mixed with 1: 5 parts of distilled water turns into a milky micro-emulsion that looks like fresh milk ready to use.
- Stiff or dried suede are hydrated and relaxed with Hydrator 3.3 to pre-dimension for a proven effective fatliquoring system.
- Fatliquor 5.0 typically works after hydration with Hydrator 3.3 to open up the fibrous structure, ensuring thorough and even absorption of fat and oil.
- The fat plumps the suede with fullness and the oil lubricates each suede fibril like millions of interconnecting hinges to glide over one another smoothly once the water content evaporates.
- Effective fatliquoring results in softer suede with increased tensile and tear strength.
- The fat content in Fatliquor 5.0 plumps up the suede, preventing it from easily collapsing into creases and wrinkles during stress or flex.
- The oil content lubricates the fibers, allowing them to slide over one another smoothly like millions of interconnecting hinges.
- It helps to keep suede at its optimum physical performance and prevent premature aging.
- It softens the suede when dry, providing stretchability, compressibility, and flexibility while significantly increasing its rip tensile strength.
- When Fatliquor 5.0 is applied, the water-encased molecule breaks free when an ionic attraction occurs between the fat and oil with the suede fiber.
- The excess free water content is wicked out, leaving breathing space for the natural transpiration of the suede.
- Fatliquor 5.0 carries an ionic negative (-ve) charge to hydrogen bond with the ionic positive (+ve) charge of the suede fibers, thus freeing up pores for better breathability.
- Unlike other stuffing conditioning oils that just fill up, darken, and suffocate the breathing pores.
- Fatliquor 5.0 conditioning is for replenishing the original fat and oil that diminishes through sun bleaching, aging, heat, and alkaline over-exposure or cleaning.
- Fatliquor content retained after a universal tannery when dries varies by an average of 14% depending on the suede type and its usage.
- Fatliquor percentage drops as the fat and oil content diminishes through aging and heat, or when it is leached out by water or chemical overexposure during cleaning.
- The Fatliquor content required by the suede is based on the weight of the percentage of remaining fat-liquor.
- Fatliquor requirement is simply calculated by the weight difference in percentage.
- If the weight of the suede is 100gm and the suede moisture reading is less than 1%.
- Applying 80gm of Fatliquor 5.0 will deliver a result incremental of 13.3% fatliquor when dry as the 66.6% water content evaporates.
- Hydrator 3.3 is used both as a hydrator to relax, open up the inter-fibrillary spaces, and facilitate and redistribute colloidal water movement.
- Besides, protonating is used to post-clean fatliquor surface remnants.
- Hydrator 3.3 to Fatliquor 5.0 ratio practice is 2 to 1, and it works out to be approximately 160gm of Hydrator 3.3 plus 80gm of Fatliquor 5.0 to replenish 100gm dry suede, from less than 1% back to the original tannery up from an average of 14% fat liquor content.
- Fatliquor 5.0 by weight content is comprised of 16.66% ionic negative (-ve) charged fat and oil, encased in 83.33% of water.
- Fat liquor water content that encased the fat and oil molecule in an emulsion suspension when hydrogen bonds with the ionic positive (+ve) suede protein fiber break free and discharge clear from the suede structure to the surface.
- Always pre-condition suede with Hydrator 3.3 to relax, and open up the fiber structure before Fatliquor 5.0.
- A fully fat liquor replenished suede maintains an average of 14% fat and oil content, while vegetable-tanned suede is more thirsty.
- Insufficient fat-liquoring (fat and oil) content may remain stiff and may also suffer cracking from staking, massaging, or flexing.
- When crispy dry, prior surface contamination/damages may darken as soiling particulates resurface.
- Removes surface soiling particulates with Eraser 5 for suede.
- Stretching the dark areas lightly will also lighten the appearance.
Posted by Larry Bauman on 31st Jul 2017 - The Lazarus Effect https://leatherdoctor.com/sheepskin-care-kit-sr3/#product-reviews
This product revived my 40-year-old Sheepskin coat that cracked at the touch of it after applying another company's 'Restoration' product. That other product ruined my coat, and I was about to throw it away but took a chance on the Leather Doctor. After applying Hydrator 3.3, I saw an immediate change. I then continued with the Fatliquor 5.0 and was shocked to see the change. My coat is now as soft and supple as it was when I purchased it in 1975! Don't even take a chance on valuable leathers with other companies' products, this one will amaze you with its results.
Edited: April 1, 2025 | April 19, 2025 by Roger Koh
