Peeling is one of the most worrisome and even more unpleasant problems that can happen after you finished a leather edge, but actually what is peeling? Why it happens? How can it be solved?
The peeling consists in "detaching" the entire paint from the edge, which is removed as if it was a single piece of plastic.
When does the peeling phenomenon occur?
Peeling occurs when the paint does not have a proper adhesion to the leather. When the first layer of leather edge paint does not have a good adhesion, all the leather edge finishing is compromised, especially on items with very consistent leather edges, obtained with numerous colored edge paint applications.
What does the adhesion of the edge paint to leather depend on?
The paint must penetrate into the leather to have a good level of adhesion, once penetrated, during the drying phase, the resin that makes up the paint binds with the fibers of the leather thus ensuring the adhesion of the paint. The greater the penetration into the leather, the greater the adhesion.
What can reduce or prevent penetration?
In leather edge finishing there are generally two main cases that can reduce the paint penetration:
- An excessive preventive process (like burnishes) that completely closes the leather edge surface. This type of work was used in the past by artisans, because at that time there were no leather edge paints with high quality features such as today - Burnishing (generally performed using burnisher wood tool) the edge is completely closed, the fibers near the surface are burned then the paint has not enough space to penetrate and even less to bind with leather fibers. It will follows an easy peeling.
- Oily, greased or water-repellent leathers. When using one of this types of leather (commonly used for belts, saddlery items, hunting leather items), it is necessary to first test the penetration and adhesion capacity of the leather edge paint. Since the paints are almost exclusively water based, or in any case with very low percentages of solvent inside, these will encounter great difficulty in penetrating the leather, since the type of leather itself tends to repel the paint. This can also cause a peeling that does not occur immediately, but in a short-medium period over items lifetime.
How to solve the problem of peeling?
In the event that this is due to the type of processing, simply avoid the wood burning phase and the problems will no longer occur. This is one of the main differences between the old and the new way of working on the leather edge.
In the case that the lack of adhesion depends on the leather, the problem can be solved by using a basecoat to be used as first coat in combination with specific additives, which favor the leather edge paint penetration into the leather.
The use of additives, however, will change the original paint, so this will lose some of its characteristics. More applications of the first coat may be necessary, for this reason they should be used only in cases where there has been a proven difficulty in adhesion.