In this article we have already covered the topic of reinforcements, those hidden components that are essential to shape a shoe, to make it comfortable, safe, reliable, and convenient for our feet.
In that text we met Salpa, a particular material, perhaps little known, but one that deserves a closer look to find out what it is, why it is suitable for quality shoes, and, most importantly, why it is more environmentally friendly than other ‘fellow components’ that do the same job as it does.
WHAT IS SALPA
To put it simply, salpa is nothing more than regenerated leather, or rather, to put it in European legislation, it is a regenerated material of leather fibers. It is defined exactly as follows:
“A material consisting of tanned hides and then mechanically or chemically disintegrated into fibrous particles, small pieces or powders and subsequently, with or without the combination of chemical binder, processed into sheets.”

Why keep it simple and just talk about ‘regenerated leather’ or ‘regenerated leather’ is not good? It is important to clarify this because, as is sometimes said, to speak well is to think well. And in this, as in many other areas of fashion, it is important to understand well what you are talking about so as not to fall into misunderstandings that are not quite right. Just talking about ‘regenerated leather’ could lead the consumer to believe that the material purchased is actually leather when in fact it is an artificial product made from leather production waste.
WHERE THE SALPA COMES FROM
Here, let’s look at what is used to bring salpa to life and through what process it takes on texture.
In the tanning stage, all hides are trimmed and shaved. The scraps that result from these processes are used for regenerated leather (let’s call it that for convenience). Shoe factories in the mounting stages of a shoe also cut and trim hides, and the same is done in the processing of any other leather goods.
All of these scraps are collected by those who make salpa, preventing them from further burdening landfills.

Once the waste materials are collected, they are ground in special machines and water is added to the powders thus generated. This creates a slurry that is treated mechanically and then chemically with tannins, fatliquors and dyes. After that, the slurry is diluted and mixed with natural latex to make the fibers bind.
The next step, similar to that by which paper is made, is very interesting: the dough is spread evenly over a thin cloth so that it resembles a sheet. Water, by gravity, drains between the textures of the substrate. Then begins the dewatering stage by suction or squeezing. To remove residual moisture, the process ends with a step in special ovens.
A long and not uncomplicated process, then, designed to perfection to obtain a quality product, despite being derived from waste raw material.
WHY SALPA IS BETTER
The regenerated leather fiber material has some very interesting characteristics: it is a sustainable material that, by using production waste, avoids the waste of resources.
Despite being born from a form of recycling, it ensures high quality and safety for consumer health, fully complying with the European REACH regulation on chemicals.

And last but not least, the windlass turns out to be durable, easy to clean and long-lasting.
Returning to reinforcing materials for footwear, salpa is chosen to give body to parts of the footwear that must accommodate the curvatures of the foot well and at the same time must retain its shape for a long time despite the considerable stresses and strains to which the material is subjected. That said, salpa turns out perfect and has all the makings of one of the best reinforcing materials available on the market today.
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