The treatment of moldy leather

Some leather surfaces get a whitish coating, blackish spots or take an unpleasant odour due to improper storage. In most cases it's mold.


Mold spores are not completely removed by a superficial cleaning. The majority of the mold is not visible. Therefore just cleaning the surface is not sufficient. We recommend to wash the leather garments with LEDER FEIN Leather & Fur Wash Concentrate and to treat before with LEDER FEIN Leather Fixative. Please pay attention to our washing instructions for leather clothing. The Fixative kills the mildew and the detergent washes the smell out. On extremely strong smelling objects, the smell can't completely be eliminated.

Important: Never store the clothing again in a bag or in a humid environment without air circulation. Otherwise the mold comes back soon.


The following instruction is for pigmented leather (colour finish on the surface). In case of other types of leather, always contact a specialist first. In particular open pore leather (suede, nubuck and aniline leather) must be treated cautiously!

Leather should be stored at room temperature at a humidity of 40 to 60 percent. An adequate air circulation must be ensured. Air humidity of more than 70 percent, high temperature and lack of air exchange support the growth of fungi and bacteria enormously.

We cannot answer comprehensively if mold can be removed with cleaning and care products alone. It largely depends on the duration the leather was exposed to adverse environmental conditions and every case has to be looked at differently. Little bit of mold that appears on vintage car seats after a few months, usually can be removed by simple means. Upholstery parts, where the mold has spread over several years, are rarely removable. The reason is not only the visible soiling on the leather. Mostly the entire inner core of the upholstery is infected with mold and the smell remains even after it is thoroughly cleaned. The mold spores are blown out together with an unpleasant odour.

Spraying air fresheners or other perfume to mask the smell does not solve the problem either. It only results in a mixture of perfume and mildew smell. Such severe cases can only be solved by replacing upholstery and leather by a saddler.

For lighter mold growth following procedure is recommended: All leather surfaces should be cleaned with COLOURLOCK Strong Leather Cleaner. The largest part of the mold is invisible. Therefore all surfaces must be cleaned thoroughly to remove all mold spores as much as possible. This includes frame, feet (furniture), but also the entire interior such as interior roof, panels, carpets, etc. (cars).

In the past different products for general mold killing were tested. Vinegar essence and isopropyl alcohol were the best in the test. Alcohol however, is out of the question for leather, because it dissolves many surfaces. But vinegar essence is an ideal product. Leathers is in the acidic state after the tanning process. Over time the pH levels within the leather shift and the leather becomes slightly unstable. The correction of the pH levels is therefore a recommended measure for older leather. Treating the leather with vinegar essence nourishes the leather. Mix the vinegar essence (usually twenty-five percent acetic acid) with same amount of water. Ensure all surfaces are treated with this mixture. Not just the leather. Don’t wet the area too much while working.

This treatment should also remove the smell of mold if leather had not been incorrectly stored for too long. To verify this, park the car for a while in the sun and keep the windows closed or heat the furniture in front of a sunny window or with a hair dryer. Repeat the process until no smell is noticeable. COLOURLOCK Odour Remover (Smell Killer) can be used additionally. Also, try to detect which surface is the origin of the smell. Heat the surfaces and check every part. This ensures the source of the odour is treated.

The appropriate aftercare is important for sustainable success. In particular, the use of vegetable/animal fats and oil based care products provide the perfect breeding ground for re-infestation. It is therefore important to care with synthetic products. COLOURLOCK Leather Protector and COLOURLOCK Elephant Leather Preserver are based on synthetic oils and fats to ensure a long lasting conservation without increasing the risk of mold. COLOURLOCK Leather Protector is first choice for dull leather. It contains oils that keep the leather soft and antioxidants that reduce the degradation of the leather. COLOURLOCK Elephant Leather Preserver is recommended for shiny leather and for leather stored in areas like the house shed which remains in risky storage conditions. As it’s as waxy product, it stays more on the surface and provides better protection against mold. Both products are very intense and a regular economical application is always better than intensive treatments.

The best protection against new mold is a secure storage! Only the use of care product cannot permanently prevent mold. It is not necessary to constantly check the temperature and humidity, but clearly wrong storage locations and conditions should be avoided at all costs.
This Porsche cabriolet had been driven in rain with the top down and stored in a garage immediately after with all windows and doors shut. The mold was on all leather surfaces. After the recommended treatment, the leather was perfect again and the vehicle could be enjoyed without any restrictions.
This Porsche from Lisbon was full of mold, too, due to humid storage for several months. After two days of intense cleaning and a colour refreshment, the vehicle regained its beauty. It was only a matter of luck, though, that the moldy scent had not penetrated deep into the upholstery yet.

Recommended products

Leather Cleaner with sponge
Ideal for cleaning leather car and furniture upholstery, bags, suitcases or garments.The Leather Cleaner is provided in a foam dispenser bottle. Foams clean the leather more efficiently than liquid agents, the consumption is considerably smaller, and the leather does not become wet, which could otherwise become hard after drying.Firstly, clean the leather thoroughly before refreshing the colour or applying care products. Use COLOURLOCK Mild Leather Cleaner against normal soiling. Cleaning before treatment prevents the dirt sticking to the leather's surface. Our COLOURLOCK Leather Cleaning Brush effectively removes ingrained dirt (use circular motions and work from seam to seam). After cleaning, it is always best to apply a care product to protect it against general wear and future staining.Amount: 200 ml Mild Leather Cleaner. This is usually sufficient for the cleaning of a whole car interior or set of furniture.Amount: 1 litre Application of Leather CleanerAlways test any products first on a hidden area in case they affect the colour.Dispense some foam on a sponge or brush. Do not apply to the leather directly! Clean the leather from seam to seam using the foam; repeat several times, if necessary. Remove dirty foam residue with a slightly moistened piece of cloth, then allow to dry.On older leathers, stains might sink into the surface, or perceived dirt might actually be colour damage. Such stains cannot always be removed by cleaning, in which case, use COLOURLOCK Leather Fresh for refreshing the colour, or ask us for advice.These products are also suitable for "Cool Leather/SRT (SunReflective Technology) Leather"!
Available Sizes

Leather Protector
To maintain the surface, we recommend our Leather Protector. It contains antioxidants, which stops the leather's decay, and its UV filters protect the surfaces from colour fading and will make them supple once more.Amount: 150 ml. This is usually sufficient for the one-time treatment (minimum) of a complete car interior or a set of furniture.; 1litreApplication: Always test any products first on a hidden area in case they affect the colour!Use COLOURLOCK Leather Protector when the leather has dried completely from cleaning or colour refreshment, ideally on the following day. Apply with a soft cloth and let dry without polishing. One application is sufficient. Strained surfaces (heavy use or in sunlit areas) should be treated every three months. Clean before use to prevent dirt sticking to the surface.These products are also suitable for "Cool Leather/SRT (SunReflective Technology) Leather"!
Available Sizes

From £19.06*
Refresher for scratches
Leather Fresh Dye
Leather Fresh is a colour refresher (dye) for scratches, worn, or faded leather. Leather Fresh is ideal to refresh colour damages on car leather, furniture leather, leather garments and handbags. Do not use on porous leathers unless colouring the entire surface - it can make the surface appear patchy. It can be sponged on or sprayed using an airbrush.  Application Always test any products first on a hidden area to test for colour match!Firstly, clean the leather thoroughly and prepare the surface. Use Mild Leather Cleaner for normal degrees of soiling or Strong Leather Cleaner to remove heavier dirt (where the leather has been neglected for many years). Cleaning prior to treatment ensures the paint bonds to the surface well and ensures durability. Use Leather Cleaning Brush to effectively remove all ingrained dirt. Cleaning removes dirt but for long lasting results you should also de-grease using Degreaser.Use a sponge to apply the colour evenly, working from seam to seam. Dry afterwards with a hair dryer. On small spots, a one application is sufficient. Apply multiple thin layers and dry each layer using a hair dryer.A day later, after it dries, apply Leather Protector. It gives the leather a good sheen and helps blend the repair. It contains antioxidants, which stops the leather's decay, and its UV filters protect the surfaces of old and valuable leathers from bleaching and fading. Also keeps the leather supple.  46 standard colours and prepared special colours according to sample or manufacturer name.Find car leather colours for Leather Fresh Dye in our Car Leather Repair category.
Available Sizes

From £29.91*
Elephant Leather Preserver 125 ml
Ideal for the care of leather which is exposed to the weather, or for conserving extremely dry or antique leather.Designed for treating genuine "Pull Up" furniture leather (oiled leather). Do not use on Bycast or polyurethane-coated (PU) leather.ApplicationAlways test any products first on a hidden area in case they affect the colour.Rub some preserver onto a clean, soft piece of cloth and apply to the leather. If required, use the cloth to give a final polish. The fat is difficult to use when it’s cold, so be sure to work at room temperature or warm it slightly with a hair dryer.COLOURLOCK Elephant Leather Preserver protects and waterproofs all types of nappa leather.

Leather and Fur Wash Concentrate
Before washing please note: Heavily soiled garments or greasy collars, cuffs etc. should be pre-soaked in luke-warm water and the problem areas pre-treated with the Wash Concentrate and a soft brush. With leather garments of more than one color, or those made from a mixture of leather and textile, or with a light colored lining, some color-bleeding can occur. In such cases always soak in LEDER FEIN® Leather Fixative before washing. Never wash two different garments together. Always wash the two or three parts of a dress or trouser suit, together. Fading and scuff marks may be hidden by the soiling and can become visible after cleaning. On some leather types the dyes have not been fixed to the fibre. Others are coated with oils or waxes. Such garments will be clean after washing but will have a changed surface or appearance. Loose buttons or too loosely sewn decorative applications must be removed or secured before washing. Sheepskins with a white underside: Always cut off a small piece and use it for a test. If it becomes hard, it means the garment has been subject to a kind of tanning that is washed out in water. In which case, do not wash. Leather Fixative Pre-treatment LEDER FEIN® Leather Fixative is used to fix colors on leather garments during washing. It can also be used for the removal of water stains on natural and aniline leather. For leather-textile mixtures, multi-colored garments, single-colored garments in black, red, blue, bordeaux and green: Always pre-soak in a basin with Leather Fixative! Effect: Fixes tanning agents, colors, and lipids inside the leather. Prevents the colors from washing out. Use preferably prior to washing.  Soak in a basin or bathtub, not in the washing machine. Add half a bottle to approx. 10 litres hand hot water, max. 30 °C until covered. Motorcycle suits: use a full bottle. Soak the garment thoroughly for approx. 60 minutes, moving occasionally. Put it into the washing machine, without rinsing. Careful: The product contains natural volatile acids. Avoid skin contact, use rubber gloves. Wash off skin or eyes with generous amounts of water. Keep away from children.  Leather & Fur Washing Concentrate Hand Wash Instructions Suitable for hand-washing all suede and nappa leathers, including jackets, coats, shirts, trousers, motorcycle suits and gloves. Depending on the garment size use ⅓ – ½ bottle + approx. 12 litres of warm water. Cover the garment. Keep the temperature below 35°C (95°F). For a complete motorcycle suit or large coat, use 1 bottle and enough water to cover. Soak for about 30 minutes and wash by hand. Treat heavy soiling with a soft brush. When clean, remove and rinse once in clean warm water. Surface Cleaning: using a thin concentrate 1:50, wipe the surface or use a brush.  Leather & Fur Washing Concentrate Machine Wash Only use the delicates or wool program and do not exceed 35°C (95°F). Suitable for all suede and grain leather, such as jackets, coats, shirts, trousers, folklore costumes, motorcycle clothing and gloves. Also ideal for leather/textile-combinations. Depending on garment size add ⅓ – ½ bottle to the machine. Motorcycle suits or large coats will need one whole bottle. Heavy soiling: soak for 1 hour and pre-treat with a soft brush dipped in concentrate. Wash with the delicates or wool program at no more than 35°C (95°F). At the end of the wash-cycle, only spin for about 30 seconds. Remove the wet garment, shake and stretch out the folds. Hang or lay the wet garment on a towel at room temperature away from sun or heat. This can sometimes take several days, depending on the leather…but it’s worth it. Important: Never dry in a drier or with heat! After drying, the leather fibres will be stuck together. Pull and stretch the garment into shape in all directions and, if needed, cold tumble dry (inside out), for about 15 - 30 minutes. Do not use heat. Nubuck and suede should be brushed with a soft brush.   The Care of Leather Garments Coated Top-Grain Leather Many top-grain leathers (such as motorcycle leather) have pigmented protective coatings to make them waterproof and more resistant to fading and staining. These leathers are easy to recognize, as rubbed-on moisture will not sink in and darken the leather. Care instructions: Scuffs and wear can be easily repaired with COLOURLOCK Leather Fresh in the correct tone. Top-Grain leather clothing should be protected and nourished by wiping with LEDER FEIN® Leather Care & Waterproofing Oil at least twice a year. This prevents cracking, shrinkage and stains.  Open Pored Top Grain Leather (napa, aniline) These are leathers which are dyed throughout but, in order to maintain their look and feel, their surfaces have not been coated. A little pressure or rubbing with moisture will darken these. Care instructions: Regular treatment with COLOURLOCK Aniline Cream (every 2-3 months) will prevent water or fat stains. Older aniline leathers can be revitalized by regular treatment with our COLOURLOCK Aniline Protector. This adds softening oils, anti-oxidants, UV-filters and intensifies the dyes. For heavy fading consult a leather professional.  Suedes and Nubucks These are leathers with a velour (slightly furry) surface. Typical are pig, goat, cow-hide, nubuck or suede, deerskin, elk and lamb. Care instructions: treat at least 1-2 times per year with our COLOURLOCK Aniline Protector, an aerosol designed to protect against fading and dryness. It is also ideal for re-conditioning suedes and nubucks after washing. It restores the freshness of the color. Heavy fading of all kinds of leather can only be restored by a professional. Do not forget to waterproof the open surface of such leathers with LEDER FEIN® Leather Waterproofing Pump Spray. To remove light soiling, brush with our soft Leather Brush or use the Nubuck Eraser.
Available Sizes

Odour Remover
Some smells can be eliminated easily with our Odour Remover, and some are impossible to neutralize, even with a specialized product. Usually, cigarette, animal and urine odours are simple to remove; urine only becomes a problem when it has seeped into the leather multiple times and over a longer time span. Mildew can be treated easily only if the padding under the leather is not affected. This is generally only the case when the leather has been stored inappropriately for just a short time. Please see our information on the treatment of mildew on leather. The smell of new leather is generally not removable.Amount: 250 ml; 1 litre Application Clean all affected surfaces thoroughly before use. Always test on a hidden area first. Spray evenly on the surface and spread with a cloth. Important: Be sure to treat all surfaces and folds of large cushions (including the reverse), as well as any spaces between cushions. If applicable, repeat treatment, then let the items air out for several days.
Available Sizes

From £19.32*
Leather Fixative
Leather Fixative is used to fix colours on leather garments during washing. It can also be used for the removal of water stains on natural and aniline leather.Amount: 100 ml; 1 litre For leather-textile mixtures, multi-coloured garments, single-coloured garments in black, red, blue, bordeaux and green: Always pre-soak in a bath with Leather Fixative! Effect: Fixes tanning agents, colours and lipids inside the leather. Prevents the colours from washing out. Use preferably prior to washing.  Use in the bath, not in the washing machine. Add half a bottle to approx. 10 litres hand hot water, max. 30 °C until covered. Motorcycle suits: use a full bottle Soak the garment thoroughly for approx. 60 minutes, moving occasionally. Put it into the washing machine,without rinsing. Careful: The product contains natural volatile acids. Avoid skin contact, use rubber gloves. Wash off skin or eyes with generous amounts of water. Keep away from children.
Available Sizes

From £10.59*