Haptic evaluation of leather surfaces
Contents
Haptic of leather
Haptic designates the tactile sense (feel) as well as the perceptible properties of an object regarding its material characteristics, surface structure and consistency.
The feel of a leather is also described with the "grip" of a leather. "A buttery napa leather," a "waxy" grip of a fine aniline leather, the "plastic-like" grip of strong coated leather, or the "parchment-like" grip of an old, dry, thin leather are all descriptions of the feel of a leather. Also, the stiffness, elasticity, warmth and coldness of a material are sensed haptically.
A good quality leather feels warm and soft.
Softness of leather
Leather is a fibre mesh of infinitely many small fibre connections. The looser these are, the softer is a leather. The flexibility of the collagen fibres themselves also influence the softness of a leather. The tanner can influence the softness by greasing. But in almost every step of tanning, the tanner influences the strength of the final product. An embossed or ironed leather will always feel more firm as un-embossed and un-ironed leather. Long softening and optimal greasing ensures extra soft leather. Also, the applied tannins, influence the leather softens. If a leather is not tanned, but only dried, it is then called parchment, which is very hard and stiff.
Depending on the animal species, the fibres are also differently firm. Due to its structure, a crocodile leather is always stronger than a lambskin. Also within a skin, the fibre connections are different. On the flanks the leather is more loose than in the middle area.
Buttery soft lamb and elk napa leather gloves (Elk skin leather from Pineyard - MUD GbR).
Soft lambskin jacket and stretchable stretch leather.
Soft leather
Soft leather is an unprotected or undefined term and is used for all types of leather to describe the softness of leather. In principle, an object made of soft leather should be softer than the typical feel of such leather objects.
Strength of the leather
There are areas of use of leather, where strength or hardness is desired. Leather belts or leather straps and leather soles should not be labile but solid. A leather gun holster or a leather dice cup should also be firm.
The firmness of a leather is achieved by pressing, less fats and oils and / or by ironing and / or heat. If a leather is wet before pressing, the leather fibres become more adhesive and it becomes even firmer. It can be made that firm, that it breaks when overstretched. A denser fibre structure and the right choice of tannin also affects the hardness or strength of leather.
Parchment is untanned, dried, hard animal skin. For drums this effect is important for the sound.
Solid leather straps, drums, leather case or saddle.
Abundance of leather
The abundance of the leather describes how massive the leather feels. The leather is "filled" by large-scale retanning substances and then feels more massive.
Additional information