Suede is a type of leather recognized for its soft, velvety surface, distinguishing it from traditional full-grain leather. Its unique texture comes from using the inner layer of the animal hide, rather than the tougher outer layer used for smooth leather. The manufacturing process involves a precise set of mechanical and chemical steps, beginning with the raw material and culminating in a pliable, textured material. The final product is prized for its pliability and delicate feel.
Preparing the Raw Hide
The initial preparation of the raw animal hide, known as “beamhouse operations,” focuses on cleaning and conditioning the material. Hides must first be preserved, often by salting, to prevent the decomposition of the collagen structure. This curing step involves heavily salting the hide immediately after procurement to draw out moisture and inhibit microbial growth.
Following preservation, the hides are soaked in water to rehydrate the material and remove excess salts, dirt, and blood. Next, liming involves treating the hide with an alkaline solution to remove the hair and epidermis, which also causes the fibrous structure to swell. Remaining non-collagenous material is then mechanically removed in a step called fleshing.
After fleshing, the material is treated with enzymes in a process called bating to loosen the fiber structure and make the material softer. The hide is then de-limed to neutralize the alkaline chemicals and pickled in an acidic solution, preparing it for tanning agents.
The Leather Splitting Process
The splitting process separates the thick hide into distinct layers using a specialized splitting machine equipped with a sharp band knife. This mechanical action slices the material horizontally, producing usable leather weights from the raw hide.
The machine separates the hide into the outer grain layer and the inner flesh layer, known as the “flesh split.” The grain split is used for traditional full-grain leather, while the flesh split is the raw material for suede. Depending on the original thickness, additional middle splits may also be produced for suede use.
The final thickness of the suede is controlled by adjusting the splitting machine settings. This operation can occur either after liming or after tanning, depending on the desired final product. If splitting occurs before tanning, the material is often called a “wet blue split” when chrome tanned.
Tanning the Suede Material
Tanning stabilizes the collagen structure in the raw flesh split, converting the perishable material into durable leather. Because suede is valued for its softness and pliability, chrome tanning is the most common method, utilizing chromium salts to quickly stabilize the material.
Chrome tanning involves placing the material in a rotating drum with the chromium solution, yielding soft, flexible leather that is easily dyed. Vegetable tanning, which uses natural tannins, is less common for suede as it results in a firmer, brown-toned leather. Following primary tanning, the material undergoes re-tanning and fatliquoring, where oils are introduced to lubricate the fibers and increase softness.
After chemical treatments, the material is dried to reduce moisture content. Once dried, it is often put through a staking machine, which massages the leather to separate the fibers and enhance flexibility. The material may also be tumbled in a dry drum to introduce additional softness before final surface finishing.
Finalizing the Suede Finish
The final stage of suede production creates the characteristic soft, fuzzy surface known as the nap. This texture is achieved through mechanical sanding, buffing, or brushing of the flesh split surface. The material is passed through a buffing machine, where abrasive wheels raise the short, fine fibers of the inner hide layer.
The buffing process is carefully controlled to produce the desired fiber length and density, giving suede its distinctive tactile quality. After mechanical treatment, the suede is de-dusted to remove fine particles. The final step is the application of color, where the suede is dyed to achieve the required hue.
Dyeing often occurs in rotating drums, allowing the color to penetrate evenly. The open fiber structure created by buffing allows for good color absorption, resulting in rich, uniform colors. Protective treatments may also be applied to enhance water resistance or reduce dye migration, completing the finished suede product.