EP0155248A1

EP0155248A1 - Sole for use as a loose inner sole or as an insole

Info

Publication number: EP0155248A1
Application number: EP85850059A
Authority: EP
Inventors: Tore Evert Johansson; Bertil Laurentius Johnsson
Original assignee: NORDIFA INDUSTRI AB
Current assignee: NORDIFA INDUSTRI AB
Priority date: 1984-02-24
Filing date: 1985-02-22
Publication date: 1985-09-18
Also published as: SE8401011L; SE8401011D0

Abstract

sole for use as a loose inner sole or as an insole in shoes, boots and other footwear. The sole comprises at least three layers 1, 2, 3 of which an inner layer (2) consists of peat fibres. At least one of the other layers 1, 3 consists of textile fibres.

Description

The subject invention relates to an inner sole and insole construction for shoes, boots and other footwear.
A variety of different materials have so far been used for insoles and loose inner soles for shoes and other footwear. The material originally used for soles of this kind is cardboard. In loose inner soles made from cardboard, the cardboard was generally enclosed in layers of a fibrous material, primarily wool. However, cardboard soles have some less attractive properties. For instance, they are weak and they tend to break easily. In addition, cardboard soles are unsuitable from the point of view of permeability.
The disadvantageous properties of cardboard as a material for loose inner soles are found also in cork soles.
Leather is used in very exclusive high-quality shoes. Although soles of leather or leather waste are superior to cardboard or cork soles the costs of soles of this material are very high.
During the latter decades textile materials have begun to be used to an increasingly large extent as separate inner soles and insoles. The reason therefore is above all the advent of the needling technique which has made it possible to interconnect fibrous materials of various types and kinds into a unit that is suitable as sole material. However, also other textile production techniques are utilized for the manufacture of sole materials, such as weaving and felting.
The subject invention represents an improvement over the loose inner soles and insoles of textile materials which are commercially available today. The sole in accordance with the invention comprises at least three layers of which at least one of the outer layers consists of a textile material and the characteristic features of the sole construction in accordance with the invention are that one inner layer consists of a batt of predominantly peat material which peat layer is surrounded on either side by at least one layer of a different material. Preferably, at least one of the at least two layers surrounding the peat layer comprises predominantly synthetic fibres. Woollen fibres may be included in at least one of the sandwiching layers. Preferably, the peat layer comprises comparatively short peat fibres or peat fibres of medium length which may also include bonding elements of some kind. The bonding elements could be thermoplastic low-melt fibres or granules which melt or soften when heat treated and thus bond the peat fibres together.
The invention will be described in closer detail in the following with reference to the accompanying drawing which illustrates a sole in accordance with the subject invention to be used as a lose inner sole or as an insole, with parts having been cut away to show the various layers of the sole.
In accordance with a preferred embodiment of the invention the sole material comprises three layers, viz. one upper layer 1 of predominantly woollen fibres, a middle layer 2 consisting predominantly of peat fibres and a bottom layer 3 consisting predominantly of one or several synthetic fibre materials. The three layers are interconnected in a conventional manner, preferably by means of needling. The bottom layer 3 may be stabilized in a heat treatment operation causing the fibres to fuse together. Also the upper layer 1 as well as the peat layer 2 may include fibres or other materials having a lower melting point so that when exposed to a heat treatment they will serve as bonding elements within their respective layer. The woollen fibres in the upper layer 1 may be replaced by synthetic fibres. The various layers and primarily the outer Tayers 1 and 3 may be made from mixtures of different fibre materials.
The intermediate or centre layer 2 consists of peat fibres of various lengths. Preferably, the fibres have a length ensuring that the layer becomes dust-proof. However, for economical reasons it is not very advantageous to use longer fibres that lend themselves to spinning since such fibres are useful in the manufacture of textile materials for clothing and similar products and therefore are more expensive. The peat fibres to be used in the soles are obtained by drying peat, whereafter the fibres included in the peat are separated in a separator in a cyclone process.
The peat making up layer 2 imparts a number of advantageous properties to the sole in accordance with the invention. The peat layer 2 absorbs moisture to a larger extent than most other fibres. This means that the peat layer 2 will absorb perspiration. The peat also have bactericide properties and consequently it will prevent the generation of unpleasant perspiration odours. To a large extent the peat operates by binding and neutralizing perspiration, salts, etcetera which contributes to a pleasant climate inside the shoe. When used as a loose inner sole it keeps the foot at a pleasant and comfortable temperature and increases the air circulation inside the shoe.
The peat layer together with a top layer consisting of wool gives the sole excellent heat insulating properties. By adequate choice of the material of the bottom layer good shape permanency and stability is imparted to the sole. Additionally, the sole becomes washable. The porous structure of the sole allows the foot to breathe.
The manufacture of the sole in accordance with the invention is performed by needling the three layers 1, 2, and 3 together in a manner known per se so that long webs of material are formed from which the soles may be punched. The shape permanency is achieved by treating the layer 3 with hot air.
The sole is suitable for use both as a separate inner sole and as an insole for a number of different footwear products.
The embodiment of the invention described in the aforegoing is to be regarded as an example only and a variety of different modifications are possible within the scope of the appended claims. Additional layers may be attached to the layers 1, 3, sandwiching the peat layer 2. Such additional layer or layers may be made from a textile material but also other materials may be used, such as e.g. various types of foil.

Claims

1. A sole intended for use as a loose inner sole or as an insole for shoes and other footwear and comprising at least three layers (1, 2, 3) of which at least one of the outer layers (1, 3) consists of textile material, characterized therein that one inner layer (2) consists of a batt of predominantly peat material, which peat layer is surrounded on either side by at least one layer of a different material.

2. A sole as claimed in claim 1, characterized therein that at least one of the layers (1, 3) surrounding the peat layer (2) consists predominantly of synthetic fibres.

3. A sole as claimed in claim 1, characterized therein that at least one of the layers (1, 3) surrounding the peat layer (2) consists predominantly of woolen fibres.

4. A sole as claimed in any one of the preceding claims, characterized therein that the peat layer (2) comprises comparatively short peat fibres or peat fibres of medium length.

5. A sole as claimed in any one of the preceding claims, characterized therein that bonding elements are included in the peat layer (22).