Insole
As insole is called the to walk out looking layer of the shoe bottom, so commonly the insole.
Because the upper part of the shoe (upper) and the lower part of the shoe bottom (midsole, outsole and heel) are attached to the insole in most designs , it is considered the foundation of the shoe, gives it stability, maintains its fit and is also responsible for durability and wearing comfort is extremely important.
Insole material
High-quality shoes have an insole made of vegetable-tanned leather that is between 1.2 and 4 millimeters thick. Depending on the type of shoe, the leather is cut from the neck, belly, core or one of the transitions of the animal skin. Leather that is used for shoe bottoms is called bottom leather. A shoe bottom is everything that exists under the foot in a shoe, i.e. the outsole and midsole, heel, frame and insole. Leather promises the best comfort properties and high durability. However, it is comparatively expensive and more difficult to process. This is why insoles made of leather fiber materials, synthetic fiber fabrics, thermoplastics and specially impregnated cardboard are used in most shoes today. Inferior leather is often hidden under a glued-on half-thin insole made of leather on the heel and metatarsus, or leather is used as an insole in the visible part of the inside of the shoe and a cheaper material is used further up front. Felt is also used for orthopedic shoes.
Preparation of the insole
Leather insoles are prepared in many ways before the shoe is made. The insoles are cut or punched from the skin according to the shoe size and the shape of the last sole sheet. If the floor leather is unevenly thick, it is also leveled. The scar layer quickly becomes hard and brittle under the influence of foot sweat, friction and body heat, which is why its top layer is removed. Tailor-made shoemakers often also water the insoles and then squeeze them out in order to wash out any still unbound tannins and to be able to better adapt the insole to the shape of the last floor, especially with higher heels of the later shoe. So that the upper (the lining) does not rub against the edge of the insole, it is broken on the foot side. The glaring (= notching in the transverse direction) of the ball of the foot on the underside of the sole serves to improve flexibility. Individual designs require further preparatory work on the insole.
Problems with leather insoles
If the direction of pull in the leather is not observed when cutting or punching the insole, this can lead to worn shoes after a short time. Problems that look like worn-on shoe heels and are often due to the inadequate quality of the back (stiff) caps or small dents can be caused by a leather insole if it does not fit exactly with the inguinal heel or has not been milled off precisely. Because the leather insole changes in length again and again due to moisture, cracks and gluing, this is no easy task. If the grain layer is not split off, it can also cause problems on the underside because it often becomes razor-sharp at the stitch holes of sewn floor structures, damages the thread and reduces the durability of the shoe.
Insole and comfort
Apart from the material, production and processing costs, insoles made of material compositions or non-leather material have several disadvantages compared to leather insoles. The poorer shoe climatic properties such as breathability and sweat absorption are particularly serious for the wearer . The resulting poorer wearing properties are noticeable in burning feet, foot sweat, cold feet in winter and hot feet in summer. Attempts are made to compensate for this with additional insoles (fur insoles in winter, sweat-absorbing insoles in summer).
Word origin
The origin of the term insole is unclear and there are various attempts to explain it. A widespread explanation leads the term back to the burning sensation of the sole of the foot, which becomes noticeable when the leather of the insole shows tanning defects: then the sweat of the feet can detach tannins and additives from the leather, which cause a burning sensation in contact with the skin . Or burning occurs because the insole is inserted with the grain side towards the foot and the leather grain (top layer) has not been removed. Another explanation of the term insole leads it back etymologically to the 18th century and describes the fact that the inner shoe sole was made from a smaller leather, in which the brand of the animals is usually located. Another theory says that the leather burn caused by frequent wearing , in which sweat, pressure and heat lead to the brittleness of the leather and a color change from dark brown to black, gave rise to the name.
See also
literature
- Helge Sternke: Everything about men's shoes . Nicolai, Berlin 2006, ISBN 3-89479-252-3 .
- Lászlo Vass, Magda Molnár: handmade men's shoes . Könemann, Cologne / Tandem, Königswinter 2000, ISBN 3-89508-111-6 .
