Leather and Related Products Industry Terminology

Aniline leather

Leather dyed with transparent aniline dyes without an opaque pigment topcoat, leaving the natural grain, pores, and markings visible. It offers a soft, luxurious hand and rich patina but lower stain/UV resistance compared with pigmented finishes.

Usage examples: - “The premium line uses aniline leather to showcase the natural grain and patina.” - “Expect some shade variation; it’s an aniline article with minimal finish.” - “We need to specify care instructions—aniline scuffs and stains more easily.”

ASTM

American Society for Testing and Materials, a standards body that publishes test methods widely used in North America (e.g., for tensile strength, tear, abrasion, color fastness, and finish adhesion in leather and related products).

Usage examples: - “Test per relevant ASTM methods for tensile and tear before PP meeting.” - “Our U.S. customer requires ASTM-compliant abrasion data.” - “Let’s align our SOPs with the latest ASTM leather testing standards.”

Beamhouse

The front-end section of the tannery where raw hides are processed through soaking, liming, unhairing, fleshing, deliming, bating, and pickling. It prepares collagen for tanning and generates the bulk of wastewater and odor.

Usage examples: - “Beamhouse capacity is our bottleneck; soaking and liming tanks are full.” - “Switching to hair-save unhairing will reduce beamhouse load to the ETP.” - “Beamhouse pH control is critical to avoid grain damage.”

Bill of Materials (BOM)

A structured list of all materials, components, and consumables required to produce a leather article or finished product (e.g., leather type, thickness, hardware, thread, adhesives, lining, reinforcement). Drives costing, purchasing, and production planning.

Usage examples: - “Add the leather article code and average yield to the BOM.” - “A change in lining leather affects the BOM cost roll-up.” - “Our PLM will version-control the BOM for each style.”

Bonded leather

Material made by bonding leather fibers and scraps with a polymer binder (often PU) and applying a surface coating. Lower cost and variable durability; not equivalent to genuine grain leather.

Usage examples: - “That wallet is bonded leather—essentially leather fiber with a PU binder.” - “We must label bonded leather to avoid misleading consumers.” - “Bonded leather won’t age like full-grain; manage expectations.”

Chrome tanning

The predominant tanning method using basic chromium salts (typically basic chromium sulfate) to stabilize collagen, yielding soft, stable, and fast-tanned leather known as ‘wet blue’ at the semi-processed stage.

Usage examples: - “This article is chrome-tanned then retanned with vegetable extracts.” - “We’ll convert raw to wet blue via basic chromium sulfate.” - “Chrome tanning gives heat and hydrolysis resistance for footwear.”

Collagen

The structural protein of animal skin forming triple-helix fibers. Leather making stabilizes collagen via tanning and lubricates it to achieve desired mechanical and sensory properties.

Usage examples: - “Tanning crosslinks the collagen triple helix, preventing putrefaction.” - “Over-liming can damage collagen fibers and weaken tear strength.” - “Fatliquoring re-lubricates collagen to restore softness after tanning.”

Corrected-grain leather

Leather whose grain surface has been lightly sanded/buffed to remove imperfections, typically finished with pigment and often embossed to restore a uniform texture.

Usage examples: - “We buffed defects and applied pigment—now it’s corrected-grain.” - “Corrected-grain improves yield on scarred hides.” - “Embossed corrected-grain gives a uniform, durable surface.”

Crust leather

Leather that has been tanned and dried but not yet finished with dyes, pigments, or protective coatings. A flexible intermediate traded for later finishing.

Usage examples: - “Ship in crust; the brand wants to finish color locally.” - “We’ll grade the crust for selection before finishing.” - “Crust storage must avoid mold—control humidity.”

Drum dyeing

Coloring leather in a rotating drum so dyes penetrate through the cross-section. Affects shade uniformity, depth of color, and light/solvent fastness.

Usage examples: - “Increase drum dye time for deeper penetration on this thick article.” - “Uneven shade suggests the drum was underloaded.” - “Drum dyeing after retan ensures through-dye on full-grain.”

Effluent Treatment Plant (ETP)

Onsite facility that treats tannery wastewater to remove solids, sulfides, BOD/COD, salts, and metals before discharge or reuse. Critical for environmental compliance and community acceptance.

Usage examples: - “Our ETP upgrade targets sulfide and chromium removal.” - “Regulators will audit ETP discharge for BOD/COD compliance.” - “ETP sludge handling must meet hazardous waste rules.”

Embossing

Impressing a pattern or texture into the leather surface using heated plates or rollers. Used to add aesthetic effects, restore texture after correction, or improve uniformity.

Usage examples: - “Run a pebble emboss to hide minor grain defects.” - “Heat and pressure must match the embossing plate spec.” - “Croc emboss sells well in small leather goods.”

Finishing

The set of processes applying dyes, pigments, binders, waxes/oils, and protective topcoats, plus mechanical actions (ironing, plating, milling) to achieve target color, gloss, feel, and performance.

Usage examples: - “Switch to waterborne finishing to cut VOC emissions.” - “Topcoat gloss and rub fastness need to meet spec.” - “We’ll plate after finishing to level the surface.”

FOB (Free On Board)

An Incoterm indicating the seller delivers goods loaded on board the vessel at the named port; risk and cost transfer to the buyer at that point. Common for international leather goods trade.

Usage examples: - “Price is $48 FOB Ho Chi Minh; freight is on the buyer.” - “FOB terms shift risk at the port of shipment.” - “Compare FOB vs DDP to understand landed cost.”

Full-grain leather

Leather with the entire grain layer intact, minimally finished to preserve natural character. Highest strength and durability with visible natural markings.

Usage examples: - “Specify full-grain for premium handbags.” - “Full-grain breathes better and patinates over time.” - “Avoid heavy correction to maintain full-grain status.”

Grain

The outer surface layer of the hide/skin, characterized by natural pores, wrinkles, and hair follicles. Determines appearance, breathability, and strength.

Usage examples: - “The grain break should be tight with minimal looseness.” - “Pore structure helps identify species from the grain side.” - “Grain damage during liming reduces grade.”

Hand (hand feel)

The tactile sensation of leather (softness, fullness, elasticity, temperature feel). Influenced by fatliquoring, milling, thickness, and finish chemistry.

Usage examples: - “The hand is too boardy; increase fatliquor and milling.” - “We want a buttery hand for the Nappa article.” - “Finish build is affecting hand—reduce binder.”

Hydrolysis resistance

The leather’s and finish’s ability to resist chemical breakdown in the presence of moisture and heat over time, critical for PU-coated leathers and humid environments.

Usage examples: - “Test hydrolysis resistance for tropical markets.” - “PU finishes with poor hydrolysis resistance will peel.” - “Chrome retan improves hydrolysis resistance in footwear uppers.”

ISO 17075 (Chromium VI)

International test method for determining hexavalent chromium content in leather. Many markets require non-detectable levels due to health concerns.

Usage examples: - “We’ll certify Cr(VI) non-detect per ISO 17075-2.” - “Customer requires periodic ISO 17075 testing.” - “Avoid oxidizing conditions in finishing to prevent Cr(VI) formation.”

IULTCS

International Union of Leather Technologists and Chemists Societies; publishes widely recognized official leather test methods across chemical, physical, and performance domains.

Usage examples: - “Follow IULTCS methods IUC/IUF/IUP for lab testing.” - “Our SOPs cite IULTCS official methods for global alignment.” - “Auditors checked conformity to IULTCS standards.”

Latigo

A robust, usually combination-tanned (chrome then veg re-tan), stuffed leather known for strength and oil/water resistance, commonly used in straps, belts, and saddlery.

Usage examples: - “Order Latigo straps for equestrian gear.” - “Latigo’s combo tan gives strength and some oil resistance.” - “We need heavy veg-re/oil Latigo at 10–12 oz.”

LCA (Life Cycle Assessment)

A standardized method to quantify environmental impacts across a product’s life cycle (e.g., GHG, water, eutrophication). In leather, scopes may include cattle rearing, slaughter, tanning, finishing, and transport.

Usage examples: - “The LCA shows most impacts in farming, not tanning.” - “We’ll publish a cradle-to-gate LCA for the article.” - “Hotspots from chemicals and energy were identified in the LCA.”

Lead time

The elapsed time from order to delivery, encompassing procurement, tanning/finishing capacity, and logistics. Managed via planning, safety stock, and supplier coordination.

Usage examples: - “Wet blue lead time is four weeks; finishing adds two.” - “Longer lead time during peak season affects OTIF.” - “Secure chemical supply to protect critical path lead time.”

Liming

A beamhouse step using alkali (lime) and sulfides to swell and open fiber structure, remove hair/epidermis, and saponify fats, preparing hides for further processing.

Usage examples: - “Reduce liming time to control grain looseness.” - “Sulfide dosage in liming affects unhairing efficiency.” - “Post-liming delime must gently reduce pH for bating.”

Milling

Mechanical tumbling of leather in a dry or slightly humid drum to soften, loosen fiber, and develop grain break/pebble. Influences hand and appearance.

Usage examples: - “Extended milling develops a natural pebbled grain.” - “Milling improved hand but lowered thickness.” - “Use dry milling post-finish to soften the article.”

MOQ (Minimum Order Quantity)

The minimum volume a supplier requires per order (often per color/finish/grade) to run economically, driven by drum size, setup, and dye/finish efficiency.

Usage examples: - “The tannery’s MOQ is 2,000 sq ft per color.” - “Low MOQ raises unit cost due to setup losses.” - “We negotiated MOQ by agreeing to longer lead times.”

Nappa leather

A soft, supple, usually chrome-tanned leather, often from calf, lamb, or kid. Not a legally protected term; implies a fine grain and luxurious hand.

Usage examples: - “Use Nappa for gloves; we need a soft, drapey hand.” - “Automotive Nappa must meet stringent emission tests.” - “Specify Nappa: chrome-tanned, full/top-grain, fine grain.”

Nubuck

Top-grain leather whose grain side has been lightly sanded to create a short, velvety nap. Softer and more delicate than pigmented grain.

Usage examples: - “Lightly buff the grain to create a uniform nubuck nap.” - “Nubuck needs protective sprays to resist staining.” - “We cannot emboss nubuck without losing the nap.”

Patent leather

Leather with a very glossy, mirror-like finish, typically achieved with multilayer polymer coatings (PU/acrylic). Used for formal footwear and fashion items.

Usage examples: - “Patent leather requires high-gloss, high-blocking-resistance topcoats.” - “Avoid flex cracking by careful plasticizer balance in patent finish.” - “Store patent leather to prevent sticking (‘blocking’).”

Pickling

Acidification (and salting) of delimed/bated hides to a low pH to prepare for mineral or organic tanning, controlling swelling and ensuring proper penetration of tanning agents.

Usage examples: - “Pickle to pH ~2.8 before chrome addition.” - “Salt in the pickle prevents swelling and acid damage.” - “Overlong pickling can lower area yield.”

Pigmented leather

Leather finished with an opaque pigment layer providing consistent color, improved stain/rub resistance, and higher yield at the expense of natural look.

Usage examples: - “Go with pigmented for uniform color and better rub fastness.” - “Pigmented topcoat will cover healed scars.” - “Adjust pigment/binder ratio to maintain hand.”

Pull-up leather

Leather finished with oils and/or waxes so that stretching or bending lightens the color in stressed areas, producing a distressed, dynamic appearance.

Usage examples: - “Apply oil/wax to achieve strong pull-up effect.” - “Customers expect patina and color variation in pull-up.” - “Heat setting after finishing enhances pull-up contrast.”

QA/QC (Quality Assurance/Control)

Systems and procedures ensuring products meet specifications. QA focuses on process and system design; QC focuses on inspection and testing (e.g., thickness, shade, fastness, strength).

Usage examples: - “QA audits traceability; QC checks thickness and shade.” - “Set AQL for inspection of finished leather lots.” - “QC will verify finish adhesion and color fastness.”

REACH

EU chemical regulation governing Registration, Evaluation, Authorisation and Restriction of Chemicals. For leather, key topics include Cr(VI), azo dyes, DMF, phthalates, and solvent restrictions.

Usage examples: - “Ensure SVHCs are below thresholds to comply with REACH.” - “We replaced restricted azo dyes per REACH Annex XVII.” - “Provide REACH declarations and test reports with shipments.”

Retanning

Secondary tanning stage after the initial tan to adjust body, fullness, tightness, color response, and handle using synthetic tans, vegetable extracts, resins, or polymers.

Usage examples: - “Retan with syntans and resins to tighten the grain.” - “Veg retan will improve body and burnishability.” - “Retan recipe drives softness and fullness targets.”

Saddle stitch

A hand-stitching method using two needles passing in opposite directions through each hole, creating a strong, repairable seam favored in high-end leather goods.

Usage examples: - “Hand saddle stitch for durability on luxury small leather goods.” - “Use two needles and waxed thread for a true saddle stitch.” - “Machine lockstitch won’t mimic saddle stitch strength.”

Skiving

Thinning leather along edges or specific areas to reduce bulk for folding, seaming, or layering, performed with a skiving machine or by hand.

Usage examples: - “Skive edges to 0.6 mm before folding.” - “Uneven skiving will telegraph through the top grain.” - “Adjust skiving angle to avoid feathering.”

Splits (split leather)

Layers obtained when a hide is split horizontally. The grain layer becomes top-grain; lower layers (splits) are used for suede or coated to simulate grain.

Usage examples: - “Use splits for suede or for PU-coated budget articles.” - “Grade the splits by thickness after splitting.” - “Avoid high-stress uses; splits have lower tear strength.”

Suede

Leather with a napped surface, typically from the flesh side of splits or lightly buffed lower layers, offering a soft, matte appearance.

Usage examples: - “Brush the nap to refresh the suede surface.” - “We’ll use calf splits for a fine suede.” - “Suede needs stain-resistant treatments for footwear.”

Tannery

A facility that converts raw hides/skins into finished leather through beamhouse, tanning, retanning, dyeing, and finishing processes.

Usage examples: - “The tannery is audited for ZDHC wastewater conformance.” - “Our tannery runs both chrome and veg lines.” - “Tannery capacity is constrained by finishing spray booths.”

Top-grain leather

The uppermost layer of a split hide after the grain is separated; may be lightly corrected and finished. Strong and versatile, but not as natural as full-grain.

Usage examples: - “Top-grain allows minor corrections for better yield.” - “This top-grain is lightly pigmented for protection.” - “Don’t confuse top-grain with full-grain.”

Traceability

The ability to track leather back through the supply chain (farm/abattoir, wet blue/crust supplier, finisher) to verify origin, compliance, and sustainability claims.

Usage examples: - “Implement lot-level traceability from slaughterhouse to finished lot.” - “We use mass-balance traceability for deforestation-free claims.” - “Chain-of-custody certification supports brand storytelling.”

Unhairing

Removal of hair from hides, typically using sulfide-alkali chemistry. Can be hair-destroying (dissolving hair) or hair-saving (mechanically removing intact hair to reduce pollution).

Usage examples: - “Switch to hair-save unhairing to cut ETP load.” - “Monitor sulfide levels to optimize unhairing efficiency.” - “Incomplete unhairing leads to grain pull during liming.”

Upholstery leather

Leather designed for furniture, automotive, and aviation interiors, engineered for high durability, light/rub fastness, and strict emissions and safety requirements.

Usage examples: - “Automotive upholstery leather must pass emission and flammability tests.” - “Furniture upholstery needs high rub fastness and light fastness.” - “Target thickness 1.2–1.4 mm for this upholstery spec.”

Vegetable tanning

Tanning with plant-derived polyphenolic tannins (e.g., quebracho, mimosa, chestnut). Produces firm leather with warm color, suitable for tooling, molding, and traditional saddlery.

Usage examples: - “Use veg-tan for tooling and saddle work.” - “Veg retan improves body and burnish on the edges.” - “Lead time is longer for full veg-tan sides.”

VOCs (Volatile Organic Compounds)

Organic solvents that evaporate into the air (e.g., toluene, MEK, ethyl acetate). Regulated for environmental and worker health reasons, particularly in finishing operations.

Usage examples: - “Switch to waterborne topcoats to reduce VOCs.” - “We must meet brand limits on VOC emissions in finishing.” - “Solvent capture improves VOC compliance.”

Wet blue

Chrome-tanned semi-processed hides with a characteristic blue color, used as a global trading intermediate for later retanning and finishing.

Usage examples: - “We import wet blue and do retan/finish domestically.” - “Wet blue selection affects final yield and grade.” - “Store wet blue at proper temperature to prevent mold.”

Wet white

Non-chrome tanned semi-processed hides, often tanned with aldehydes or syntans, appearing pale/white. Used to make ‘metal-free’ or ‘chrome-free’ leathers.

Usage examples: - “Metal-free wet white meets certain brand restricted-substance lists.” - “Wet white is ideal for pastel shades.” - “Adjust retan since wet white has different uptake than wet blue.”

Yield

The usable area of leather relative to total input (or the efficiency of cutting patterns from hides), expressed as a percentage or square footage per hide/side. Key driver of cost.

Usage examples: - “This article gives 78% cutting yield on the pattern.” - “Improve yield by allowing corrected-grain selection.” - “We target 15 sq ft average yield per side.”

ZDHC

Zero Discharge of Hazardous Chemicals program setting a Manufacturing Restricted Substances List (MRSL), wastewater guidelines, and conformance levels to drive safer chemistry in the supply chain.

Usage examples: - “We adopted the ZDHC MRSL across all tanneries.” - “ZDHC wastewater conformance Level 1 is now required.” - “Audit the chemical inventory against the ZDHC Gateway.”