GB2072487A - Counter stiffener - Google Patents

Abstract

A laminated counter stiffener comprises a film of a deep-drawn thermo plastic plastics material and a layer of a closed-cell, foamed, cross-linked polyolefin whose thickness decreases evenly at its edges, the polyolefin layer being inner- most.

Description

SPECIFICATION Heel for shoe In order to provide the necessary properties, conventional heels, including heel reinforcements, are made of very hard materials. These may be based on, for example, leather fibres.

Such materials are usually prepared as laminates and formed by deep-drawing. Laminates usually have a substantially uniform thickness, and it is therefore necessary to bevel such a product when used as a heel, at least at its upper edge, in order to provide satisfactory transition from the shoe in which it is incorporated to the foot of the wearer. The bevelling operation is tedious and expensive.

It has been proposed to prepare heels and heel reinforcements by spraying a thermoplastic materials. The spraying apparatus is expensive. Further, the assembly time is limited by the cooling period.

According to the present invention, a material which can be formed for use as a heel or a heel reinforcement is a laminate of a film of a deep-drawn thermoplastic plastics material 0.3 to 2.5 mm thick and a layer of a closedcell, foamed, cross-linked polyolefin whose thickness decreases evenly at its edges.

In use, the polyolefin layer functions as the inner side of the laminate.

The plastics film is preferably from 0.5 to 1.3 mm thick. It is preferably a high grade consolidated polyethylene, although films of acrylobutadiene-styrene or polyvinyl chloride may also be used.

The polyolefin layer is preferably of a closed-cell, foamed, cross-linked polyethylene.

The maximum thickness of this layer is preferably 2.5 mm.

The laminate of the invention is preferably formed by flame-laminating the plastics film and the polyolefin layer. Lamination can be controlled so that the foam structure of the latter is not impaired. The product has an inherent stability sufficient to allow deformation of the laminate, e.g. into a heel reinforcement, in a separate stage.

In deformation, the laminate is suitably heated evenly to the deformation temperature and deep-drawn, if necessary or desired, in a combined stamping/pressing tool. The thickness of the foam material layer is preferably reduced to the desired degree at its edges in the same operation, by compressing the pore structure.

The invention will now be described by way of example with reference to the accompanying drawings, in which Fig. 1 shows an embodiment of the invention in perspective view from above, and Fig. 2 shows a crosssection through the embodiment of Fig. 1.

The drawings show a laminate of a plastics film 1 and a foam material layer 2 whose thickness decreases evenly in the direction of its edges.

Products of the invention in the form of heel reinforcements are suitable for use in various shoes, including women's fashion shoes.

1. A laminate of a film of a deep-drawn thermoplastic plastics material 0.3 to 2.5 mm thick and a layer of a closed-cell, foamed, cross-linked polyolefin whose thickness decreases evenly at its edges.

2. A laminate according to claim 1 in which the plastics material is polyethylene.

3. A laminate according to claim 1 or claim 2 in which the film is from 0.5 to 1.3 mm thick.

4. A laiminate according to any preceding claim in which the polyolefin is polyethylene.

5. A laminate according to any preceding claim in which the layer has a maximum thickness of 2.5 mm.

6. A laminate according to any preceding claim which has been formed by flame-lamination.

7. A laminate according to any preceding claim in which the decreasing thickness is caused by consolidation.

8. A laminate according to any preceding claim in the form of a heel reinforcement.

9. A laminate according to claim 1 substantially as herein described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Heel for shoe In order to provide the necessary properties, conventional heels, including heel reinforcements, are made of very hard materials. These may be based on, for example, leather fibres. Such materials are usually prepared as laminates and formed by deep-drawing. Laminates usually have a substantially uniform thickness, and it is therefore necessary to bevel such a product when used as a heel, at least at its upper edge, in order to provide satisfactory transition from the shoe in which it is incorporated to the foot of the wearer. The bevelling operation is tedious and expensive. It has been proposed to prepare heels and heel reinforcements by spraying a thermoplastic materials. The spraying apparatus is expensive. Further, the assembly time is limited by the cooling period. According to the present invention, a material which can be formed for use as a heel or a heel reinforcement is a laminate of a film of a deep-drawn thermoplastic plastics material 0.3 to 2.5 mm thick and a layer of a closedcell, foamed, cross-linked polyolefin whose thickness decreases evenly at its edges. In use, the polyolefin layer functions as the inner side of the laminate. The plastics film is preferably from 0.5 to 1.3 mm thick. It is preferably a high grade consolidated polyethylene, although films of acrylobutadiene-styrene or polyvinyl chloride may also be used. The polyolefin layer is preferably of a closed-cell, foamed, cross-linked polyethylene. The maximum thickness of this layer is preferably 2.5 mm. The laminate of the invention is preferably formed by flame-laminating the plastics film and the polyolefin layer. Lamination can be controlled so that the foam structure of the latter is not impaired. The product has an inherent stability sufficient to allow deformation of the laminate, e.g. into a heel reinforcement, in a separate stage. In deformation, the laminate is suitably heated evenly to the deformation temperature and deep-drawn, if necessary or desired, in a combined stamping/pressing tool. The thickness of the foam material layer is preferably reduced to the desired degree at its edges in the same operation, by compressing the pore structure. The invention will now be described by way of example with reference to the accompanying drawings, in which Fig. 1 shows an embodiment of the invention in perspective view from above, and Fig. 2 shows a crosssection through the embodiment of Fig. 1. The drawings show a laminate of a plastics film 1 and a foam material layer 2 whose thickness decreases evenly in the direction of its edges. Products of the invention in the form of heel reinforcements are suitable for use in various shoes, including women's fashion shoes. CLAIMS

1. A laminate of a film of a deep-drawn thermoplastic plastics material 0.3 to 2.5 mm thick and a layer of a closed-cell, foamed, cross-linked polyolefin whose thickness decreases evenly at its edges.

2. A laminate according to claim 1 in which the plastics material is polyethylene.

3. A laminate according to claim 1 or claim 2 in which the film is from 0.5 to 1.3 mm thick.

4. A laiminate according to any preceding claim in which the polyolefin is polyethylene.

5. A laminate according to any preceding claim in which the layer has a maximum thickness of 2.5 mm.

6. A laminate according to any preceding claim which has been formed by flame-lamination.

7. A laminate according to any preceding claim in which the decreasing thickness is caused by consolidation.

8. A laminate according to any preceding claim in the form of a heel reinforcement.

9. A laminate according to claim 1 substantially as herein described with reference to the accompanying drawings.