How Synthetic Leather Is Made & What to Know About Release Paper

What Is Synthetic Leather Made From?

Synthetic leather is made from a polymer coating — most commonly polyurethane (PU) or polyvinyl chloride (PVC) — applied onto a textile or non-woven fabric backing. The result is a layered composite material that replicates the surface appearance, texture, and handling characteristics of animal leather without using any animal hide. A third category, microfiber synthetic leather, uses ultra-fine polyester or nylon fiber substrates treated with PU resin to achieve a closer approximation of the pore structure and hand feel of full-grain leather.

The base components of synthetic leather at a material level are:

• Substrate: woven fabric (typically polyester or cotton), knitted fabric, or non-woven fiber mat — this provides tensile strength and tear resistance
• Adhesive or tie coat: a bonding layer that anchors the polymer skin to the substrate
• Foam or intermediate layer: optional in some constructions, used to add softness and thickness
• Skin coat: the primary PU or PVC layer that forms the visible surface
• Surface finish: a top coat providing color, gloss level, and functional properties such as abrasion resistance, UV stability, or water repellency

PU-based synthetic leather accounts for the majority of global production and is preferred for apparel, footwear, and furniture applications due to its softer hand, better breathability compared to PVC, and lower environmental load. PVC leather remains widely used in automotive interiors and heavy-use upholstery where cost and abrasion durability outweigh other considerations. The global synthetic leather market was valued at approximately $35 billion USD in 2023 and continues to expand as sustainability concerns accelerate the transition away from animal hide products.

How Artificial Leather Is Made: The Two Main Manufacturing Processes

Understanding how artificial leather is made requires distinguishing between the two dominant production routes — the dry process and the wet process — which produce different material structures and are suited to different end-use applications.

The Dry Process (Transfer Coating)

In the dry process, the PU skin is built up in reverse on a release paper carrier rather than being applied directly to the substrate fabric. The sequence is:

1. A surface finish or top coat is applied to the release paper and dried in an oven.
2. One or more intermediate PU layers (the skin body) are coated over the dried surface layer.
3. An adhesive layer is applied, and the fabric substrate is laminated onto the adhesive while it is still wet.
4. The laminated composite passes through a drying oven at controlled temperature.
5. The release paper is peeled away, leaving the fabric-backed PU leather with the paper's surface texture transferred onto the skin side.

The dry process is the most commercially prevalent method for PU synthetic leather production. Its defining characteristic is that the texture, grain pattern, and gloss level of the finished leather are entirely determined by the release paper surface — making release paper selection a central technical decision in the production process, not an afterthought.

The Wet Process (Coagulation)

In the wet process, the fabric substrate is impregnated with a PU resin dissolved in dimethylformamide (DMF) solvent, then immersed in a water bath. The water displaces the DMF solvent, causing the PU to coagulate into a microporous structure within the fabric. The material is then washed, dried, and surface-finished. The wet process produces a leather with an open-cell foam microstructure that closely mimics the breathability and compressibility of genuine leather — which is why wet-process synthetic leather is the basis for most high-performance microfiber leather used in premium footwear and automotive applications. The trade-off is higher manufacturing complexity, significant solvent management requirements, and greater energy and water consumption per linear meter produced.

How Is Faux Leather Made Differently from PVC Leather?

The term "faux leather" is used interchangeably with synthetic leather in consumer contexts, but in manufacturing terms it most often refers specifically to PU-based products as distinct from PVC. Understanding how faux leather is made in a PVC context reveals a different production route than the PU dry or wet processes described above.

PVC leather is produced by a calendering or spread-coating process. In calendering, PVC compound — a blend of PVC resin, plasticizers (typically phthalate or non-phthalate types), stabilizers, pigments, and fillers — is heated and pressed into a film between steel rolls, then bonded to a fabric backing under heat and pressure. In the spread-coating process, a PVC paste (plastisol) is spread onto the fabric carrier and cured in an oven where the plasticizer absorbs into the PVC resin, forming a fused, flexible film.

The texture of PVC leather is applied either by embossing rollers that press a grain pattern into the still-warm material immediately after formation, or by the same release paper transfer method used in PU dry-process production. PVC's higher rigidity and greater resistance to tearing make it the preferred choice for automotive seating, marine upholstery, and contract furniture — applications where long-term mechanical durability outweighs softness or breathability considerations.

Artificial Leather Release Paper: The Component That Defines the Surface

Artificial leather release paper is a coated carrier paper used in the dry-process transfer coating method. It serves two simultaneous functions: it acts as a temporary support substrate that carries the PU coating layers through the production line, and it imparts its own surface texture to the PU skin during the transfer process. When the release paper is peeled from the finished leather, the leather's surface carries an exact negative impression of the paper's surface — whether that is a fine-grain leather pattern, a smooth high-gloss finish, a matte stone or fabric texture, or any other embossed design.

The paper base is typically a high-density kraft or glassine paper, treated to achieve dimensional stability under the heat and tension of the coating line. Over this base, a release coating is applied — most commonly a silicone or polyethylene formulation — that prevents the PU from bonding permanently to the paper while still delivering a clean, complete surface transfer. The release coating must achieve a precise and consistent release force: too low and the paper separates prematurely during coating; too high and the PU skin tears or distorts on peeling.

On top of the release coating, the texture layer is applied — typically by embossing, gravure printing, or a combination of both — to create the grain pattern that will be transferred to the leather surface. This texture layer must withstand repeated exposure to the heat, pressure, and solvents of the coating process across multiple usage cycles.

How Well Do You Know the Release Paper for Synthetic Leather? Key Technical Points

Release paper is one of the most technically demanding consumables in synthetic leather production, yet it receives far less attention in purchasing decisions than the PU resin or the fabric substrate. The following properties determine whether a release paper is fit for a given production application.

Number of Usage Cycles

Release papers are classified by the number of times they can be used before the surface texture degrades to an unacceptable level. Standard-grade papers are typically rated for 3–5 cycles; premium papers for 10–20 cycles or more. The economics of paper cost per linear meter of leather produced are therefore heavily influenced by cycle count — a paper that costs twice as much but lasts four times as long is significantly more cost-effective in high-volume production.

Heat Resistance and Dimensional Stability

Coating ovens in dry-process synthetic leather lines typically operate at 100–160°C. At these temperatures, the release paper must maintain dimensional stability — it cannot shrink, curl, or expand in the cross-direction, or the PU coating will develop stress wrinkles and register errors in multi-pass production. Papers with poor moisture resistance are particularly vulnerable: moisture absorbed during storage or between production runs causes differential expansion when the paper enters the oven, leading to surface distortion.

Release Force Consistency

Release force — the peel strength required to separate the paper from the cured PU film — must be consistent across the full width of the paper and stable across usage cycles. Release force is typically measured in cN/cm and specified to a tight tolerance window for each paper grade. Variation in release force across the web width produces visible surface defects: areas of higher release force leave microscopically rougher textures in the PU skin, which read as sheen or color variation in the finished leather under raking light.

Texture Fidelity and Pattern Registration

The surface texture of release paper is the primary design tool for synthetic leather surface aesthetics. Fine natural leather grain patterns require emboss depths in the range of 20–80 μm with precise pattern registration — meaning the emboss repeat must be consistent within ±0.1 mm or the grain will appear irregular and non-natural. This is achievable in high-quality gravure-embossed papers but not in lower-cost mechanically embossed grades, which is why premium leather simulant products specify paper grade as a key quality input rather than treating it as a commodity purchase.

Solvent Resistance

PU coating formulations used in dry-process production contain DMF, MEK, toluene, or other solvents at varying concentrations depending on the resin system. The release coating on the paper must resist penetration by these solvents — if solvent permeates the release layer, it alters the surface energy of the texture layer and causes adhesion of the PU to the paper, resulting in film tearing or incomplete transfer. Silicone-based release coatings generally offer better solvent resistance than polyethylene alternatives, which is reflected in their higher cost and typical use in demanding, multi-cycle applications.

Storage and Handling Requirements

Release paper for synthetic leather production is sensitive to storage conditions in ways that are frequently underestimated. Rolls stored in high-humidity environments absorb moisture that causes edge curl and cross-direction waviness — both of which create wrinkle defects when the paper enters the coating machine. The recommended storage condition is 40–60% relative humidity at 18–25°C, with rolls stored vertically or on proper roll cradles rather than on their ends. Papers that have been stored improperly can often be salvaged by conditioning in a temperature-controlled room for 24–48 hours before use, but severe moisture uptake causes permanent damage to the paper base that no conditioning will reverse.

Choosing the Right Release Paper for Your Synthetic Leather Application

Matching release paper specification to the production application requires clarity on four variables: the coating chemistry being used (solvent type and concentration), the oven temperature profile, the required surface texture and gloss level, and the production volume that determines how many cycles the paper must deliver before replacement.

For high-volume continuous production of standard PU leather in mid-market furniture or bag applications, a medium-grade silicone-release paper with a 5–8 cycle rating and a standard grain emboss is a cost-efficient choice. For premium footwear or automotive leather simulants where surface consistency and texture fidelity are critical, a high-cycle premium paper with gravure-embossed fine grain and tight release force specification is the correct investment — the higher per-roll cost is more than offset by the reduced defect rate and the extended run between paper changes.

For specialty surface effects — high-gloss mirror finish, matte stone texture, metallic foil-transfer surfaces — papers are often custom-specified for the production line and should be trialed over a full production run before being committed to as the standing specification. Surface effects that look correct on a lab sample sometimes behave differently at production line speed and temperature, and the trial process is the only reliable way to validate compatibility before committing to a large stock holding.