Physical Properties of Upholstery Leather

The physical properties which make leather a unique and valuable material for upholstery purposes are:

High tensile strength

Resistance to tear

High resistance to flexing

High resistance to puncture

Good heat insulation

• Leather contains a great deal of air, which is a poor conductor of heat. This is an important comfort consideration.

Permeability to water vapour

• Leather fibres will hold large quantities of water vapour. This property enables leather to absorb perspiration, which is later dissipated. A significant factor in comfort.

Thermostatic properties

• Leather is warm in winter and cool in summer.
  

Mouldability

• Leather can be moulded and will retain its new shape. It has both elastic and plastic properties in wear.

Resistance to wet and dry abrasion

• These properties, concerned with wear and maintenance, are controlled by the tannage and surface finish. These have now reached high levels of excellence.
  

Resistance to fire?

• Leather is inherently resistant to heat and flame.

Resistance to fungi

• Leather is resistant to mildew.
  

Resistance to chemical attack

• The atmosphere of modern cities is polluted from the burning of carbon fuels with sulphur dioxide gas, which can accelerate the deterioration of leather. Modern leathers are tanned and dressed to resist these harmful chemicals.

The Natural Characteristics of Leather

Real leather is a natural product. It breathes, is warm and has individual characteristics which make each hide unique. Leather will always bear the marks of its natural origin and these characteristics can show as healed scars, growth marks, areas of differing fibre density and hair pore structure. These hallmarks in no way detract from the wearing qualities of the leather. They are signs discerning owners cherish when buying leather. With the passing of time and use, it develops a patina which enhances its beauty.

Growth Marks and Veins - These are an indication of the age of the animal and in that respect are similar to the graining on a piece of timber. They range from often quite pronounced marks in the neck area to subtle bands across the hide perpendicular to the backbone. Heavy growth marks are often placed on the outside backs of seating.

Scars - These form usually as a result of barbed wire damage or by the horns of other cattle. In their healed form the new skin is as strong as the remainder of the hide but unhealed damage should be avoided as tension on these parts may cause the leather to split or burst.

Grain Variation - The fibre texture varies greatly from being loose in the belly and flank areas to being relatively tight across the backbone. The looser areas consequently have more stretch.
The variation in hair pore structure is particularly noticeable in untextured leathers where clusters of open pores can sometimes be seen.

Shade Variation - No two hides are alike and due to the varying grain structure mentioned above the dyes and finishes penetrate to differing degrees in different parts of the hide to give an attractive variation. Whilst every attempt is made to achieve uniformity this is not always possible and sometimes not desirable.