In the laether manufacturing the raw material is purchased by weight, whereas the finished product is sold by area; any improvement in the area yield have a considerable commercial importance. The processes in which leather manufacture is involved reduce the area obtained in the product. The methods used to improve the leather area deteriorites its mechanicals characteristics, and yield improvement is lost in the finishing operations or in storage of leather.

A thermal treatment made on flat stretched leather immersed in a water saturated medium, before the drying step, will allow:
1. To develop a process able to improve the area in leather;
2. To improve the fixation of tanning, dyeing and fatliquoring substance, enhancing the overall leather fastness characteristic as well as it thermal resistance, reducing the environmental impact and health risk of leather articles end users;
3. To reduce the sensibility of leather to moisture variation that affect negatively the comfort and aesthetic appearance of leather products;
4. To accommodate the technology to an feasible industrial process, without deteriorating the characteristics of the tanned hides.