What Is Patent Leather?

How is patent leather made?

Patent leather is made by building a hard, glossy film, coat by coat, on the surface of tanned leather. According to SATRA, the footwear research body, most modern patent leather is based on cattle hide, and the majority is now finished with polyurethane (PU) coatings. One blend pairs PU, for a hard, glossy, durable surface, with acrylic, for flexibility.

A 2009 technical article in Leather International sets out a typical modern sequence:

1. Base leather. Usually corrected-grain leather. Patent finishes need a tight, flat grain.
2. Impregnation. A resin, typically 3–5 g per square foot, is worked in at the junction of the grain and the looser layer beneath it (the corium).
3. Base coat. A pigmented coat of 14–16 g per square foot, applied in several roller-coater passes with ironing between them.
4. Intermediate coat. A sprayed nitrocellulose layer.
5. Top coat. Up to 20 g per square foot, less on soft leathers, applied by airless spray or curtain coater in a sealed, dust-free room. It then dries for about 2 hours at 25 °C and about 10 hours at 50 °C.

SATRA calls curtain coating by far the more efficient method and says it gives the best smoothness and depth of gloss. Another route presses a pre-formed film on from transfer paper, carrying either the whole finish or just the top coat; Leather International describes this at 125 °C for 3–5 seconds at 100 bar. SATRA notes that low-cost patent leathers made by transfer coating PU onto leather splits (hide that has been split into layers) are popular for school shoes.

The 19th-century method

An 1857 Scientific American description, quoted by JSTOR Daily, starts with linseed oil boiled with white lead and litharge (lead oxide), then mixed with ochre or chalk. Three very thin coats were applied, each dried before the next, and the surface was ground down with pumice. Five or six coats of the oil and lead mixed with ivory black followed, then the varnish. SATRA says linseed oil and Prussian blue seem to have been the basis of most patent finishes for many decades, with tanners applying as many as 15 coats.

Where does patent leather come from?

Patent leather comes from late 18th-century Europe, where, according to JSTOR Daily, various methods of colouring leather and coating it with varnish were in use. SATRA’s history cites a 1793 article in The Bee describing a Mr Hand of Birmingham as having obtained a patent for flexible leather with a glaze and polish, and an 1805 patent by Charles Mollersten for a composition that gave hides and leather “a beautiful gloss”.

In the United States, Seth Boyden developed a process for making patent leather in Newark, New Jersey, in 1818, according to Britannica. JSTOR Daily reports that he apparently reverse-engineered the finish after examining high-gloss leather from Europe, and that in December 1818 he built a shop on Broad Street to make it. SATRA and the Museum of Fine Arts, Boston, date the start of commercial manufacture to 1819.

Myth vs fact: Boyden is credited with the first patent leather made in the United States, not with inventing the finish, which JSTOR Daily says existed well before him. SATRA reports that the name came from the patent office’s recognition of the process. Yet, as JSTOR Daily notes, it is still unclear who originally patented it, and any such patent has long since expired.

What are the properties of patent leather?

Patent leather pairs the fibrous body of leather with a hard, very shiny surface that comes from its coating, not from the hide.

• Gloss. The Museum of Fine Arts, Boston, describes a very hard, shiny enamel finish produced by several thin layers of coloured varnish.
• Breathability. Lower than uncoated leather. A 2021 study in the journal Coatings found that leather’s water-vapour permeability is high only when no tight synthetic topcoat is applied, and that the thicker a polymer layer, the less vapour passes through.
• Flexibility. The finish has to stay somewhat elastic, or it cracks in use (SATRA). Leather International lists poor flex resistance among typical faults, along with creasing when a thick finish sits on thin, loose leather.
• Colour. Leather International notes that patent leathers were traditionally made in black or white, for evening wear and children’s footwear.

SATRA notes long-standing demand for patent formal dress shoes, dance shoes and girls’ black school shoes. The Museum of Fine Arts, Boston, also lists purses, belts, carriage covers and helmets; JSTOR Daily mentions the patent bag.

How is patent leather graded or measured?

Rather than by named grades, patent leather is judged on how thick the coating is and which layer of hide sits beneath it. EU footwear law draws its leather categories at 0.15 mm of coating and at one third of total thickness (see the table below). Corrected-grain leather is the usual base (Leather International); a leather split with a transferred PU film is SATRA’s example of a low-cost alternative.

How does patent leather appear on a label?

In the EU, patent leather footwear is labelled either “leather” or “coated leather”, depending on how thick the coating is; Directive 94/11/EC has no separate category for patent leather. The directive defines leather as hide or skin with its original fibrous structure more or less intact, tanned to be rot-proof.

The label covers three parts of a shoe: the upper, the lining and sock, and the outer sole. It names the material that makes up at least 80% of the surface area of the upper and of the lining and sock, and at least 80% of the volume of the outer sole. If no single material reaches 80%, it gives the two main materials.

Leather broken down into fibres or powder and re-formed into sheets is not leather under the directive. Materials with no hide at all, such as vinyl, faux leather or vegan leather, cannot use either leather category, however glossy they are. The directive covers footwear only; it does not apply to bags or belts.

How do you tell good patent leather from poor patent leather?

Good patent leather has real hide under an even, clear, non-tacky film; poor patent leather shows bubbles, cloudiness, stickiness or creasing.

1. Read the shoe label. In the EU, look for the leather or coated-leather category for the upper.
2. Look at a cut edge. Find a raw edge on a strap or seam. Leather is built from intertwined, cross-linked fibres; a synthetic look-alike usually shows a knitted or woven textile support under its polymer layers (Meyer and colleagues, 2021).
3. Tilt it under a light. Leather International lists air bubbles and a cloudy, dull appearance among typical patent faults.
4. Touch the surface. A tacky surface that takes fingermarks is another listed fault, probably caused by too little crosslinker in the top coat.
5. Flex it gently. Fine creases where the material bends point to a thick finish on thin, loose leather; cracks mean the film has lost its elasticity.

Red flag: shine alone proves nothing. The Museum of Fine Arts, Boston, notes imitations of patent leather made entirely of plastic.

How do you care for patent leather?

Caring for patent leather means caring for its coating: keep it clean, keep it flexible and avoid sharp folds.

• Wipe the surface with a soft, damp cloth and dry it.
• Test any cleaner or polish on a hidden spot first. Leather International notes that base-coat resins are chosen for the resistance to cracking and solvents the leather needs, so finishes differ.
• Store shoes and bags filled out, not folded or crushed, because the film must stay elastic to avoid cracking (SATRA).

Is patent leather sustainable?

Patent leather combines the impact of leather with that of a plastic coating, so its footprint depends on both the hide and the finish chemistry. SATRA says most modern patent leather uses polyurethane coatings. Leather International reported in 2009 that genuine patent leathers were produced with a solvent-based polyester and isocyanate system, and that water-based finishes can achieve the same wet look with fewer problems and hazards. The 19th-century recipe quoted by JSTOR Daily used white lead and litharge, both lead compounds.