GB2142353A - Shock pad for synthetic sports turf - Google Patents

Abstract

This invention provides a shock pad suitable for use as an underlay for synthetic sports turf and comprising a substantially uniform resiliently compressible porous matt of an open tangle of substantially randomly extending fibres bonded at at least some points of contact, and sand filling the matt.

Description

SPECIFICATION Shock pad for synthetic sports turf The present invention relates to a shock pad for use as an underlay for synthetic sports turf.

There remains a need for an all weather such underlay which is durable and stable in use and which exhibits the required nature and degree of shock absorption to promote in the overlaid synthetic turf desirable playing characteristics both from the point of view of the users and as regards the behaviour of any equipment (e.g. ball) used. Despite the expenditure of much time, effort and resources on the problem, shock pad underlays available or proposed to date have failed to meet one or more of these requirements.

According to the present invention, a shock pad suitable for the mentioned purposes comprises a substantially uniform resiliently compressible porous matt comprising an open tangle of substantially randomly extending fibres bonded at at least some points of contact, and sand filling the matt. The shock pad underlay according to the invention is suitable for use with either filled (usually with sand) or non-filled synthetic sports turfs.

Various parameters of the shock pad underlay according to the invention can be varied to suit the underlay/synthetic turf combination for particular different uses - e.g. American football or soccer or golf etc. Important parameters in this respect are the thickness of the matt (which may for example be from 0.5 cm to 4 cm), the packing density of the fibre (which may for example be from 30 to 1 60 kg. per cubic metre, and the granularity of the sand fill. By appropriate selection of these parameters it is possible to tailor the end product to provide the optimum shock absorption and other characteristics for walking, running and falling and for the ball rebound characteristics required.

The shock pad underlay according to the invention preferably has at its underface a porous backing which allows the drainage of water therethrough but restricts sand loss and settlement.

The fibres of the matt may be of animal or vegetable origin, of synthetic material, or a mixture of any of these. Polypropylene fibre is especially suitable.

One commercially available product suitable for use as the matt to be filled with sand according to the invention is rubberised hair, an open tangle of animal hair bonded with rubbery adhesive and available in sheet form; one such sheet product is available under the name " Hairlok" from Hairlok Limited of Bedford, England. Such rubberised hair meeting Ministry of Defence Specification UK/AlD/91 9/2 is widely used as protective cushioning for the transport and storage of military components and equipment. Similar products are commercially available from other sources. The animal hair may be replaced wholly or in part by vegetable fibre and/or plastics (e.g. polypropylene) fibre.

Synthetic plastics fibre may not require a separate adhesive for the fibre bonding.

Installation of the shock pad according to the invention is simple. The porous bonded fibrous matt is simply laid (e.g. from the roll) on the prepared site, with the porous backing (if any) face downwards, and sand is then deposited thereon and brushed or otherwise worked in until the matt is fully sand filled; the synthetic sports turf is then laid over the finished shock pad. The granularity of the sand employed is selected to help provide the required playing characteristics of the turf, to avoid panning, to give good drainage and correct water swelling characteristics.

Whilst reference is made above to a sand fill for the bonded fibrous matt, and whilst sand is the most readily available material for use as such filler, sand substitutes could of course be employed within the scope of the invention.

Additives may be incorporated in the shock pad according to the invention (in the sand and/or in the fibrous matt) to combat biodegradation of the shock pad and/or to deter attack on it by animals such as rodents, insects etc.

1. A shock pad suitable for use as an underlay for synthetic sports turf and comprising a substantially uniform resiliently compressible porous matt of an open tangle of substantially randomly extending fibres bonded at at least some points of contact, and sand filling the matt.

2. A shock pad for synthetic sports turf, the shock pad being substantially as hereinbefore described.

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

Claims (2)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Shock pad for synthetic sports turf The present invention relates to a shock pad for use as an underlay for synthetic sports turf. There remains a need for an all weather such underlay which is durable and stable in use and which exhibits the required nature and degree of shock absorption to promote in the overlaid synthetic turf desirable playing characteristics both from the point of view of the users and as regards the behaviour of any equipment (e.g. ball) used. Despite the expenditure of much time, effort and resources on the problem, shock pad underlays available or proposed to date have failed to meet one or more of these requirements. According to the present invention, a shock pad suitable for the mentioned purposes comprises a substantially uniform resiliently compressible porous matt comprising an open tangle of substantially randomly extending fibres bonded at at least some points of contact, and sand filling the matt. The shock pad underlay according to the invention is suitable for use with either filled (usually with sand) or non-filled synthetic sports turfs. Various parameters of the shock pad underlay according to the invention can be varied to suit the underlay/synthetic turf combination for particular different uses - e.g. American football or soccer or golf etc. Important parameters in this respect are the thickness of the matt (which may for example be from 0.5 cm to 4 cm), the packing density of the fibre (which may for example be from 30 to 1 60 kg. per cubic metre, and the granularity of the sand fill. By appropriate selection of these parameters it is possible to tailor the end product to provide the optimum shock absorption and other characteristics for walking, running and falling and for the ball rebound characteristics required. The shock pad underlay according to the invention preferably has at its underface a porous backing which allows the drainage of water therethrough but restricts sand loss and settlement. The fibres of the matt may be of animal or vegetable origin, of synthetic material, or a mixture of any of these. Polypropylene fibre is especially suitable. One commercially available product suitable for use as the matt to be filled with sand according to the invention is rubberised hair, an open tangle of animal hair bonded with rubbery adhesive and available in sheet form; one such sheet product is available under the name " Hairlok" from Hairlok Limited of Bedford, England. Such rubberised hair meeting Ministry of Defence Specification UK/AlD/91 9/2 is widely used as protective cushioning for the transport and storage of military components and equipment. Similar products are commercially available from other sources. The animal hair may be replaced wholly or in part by vegetable fibre and/or plastics (e.g. polypropylene) fibre. Synthetic plastics fibre may not require a separate adhesive for the fibre bonding. Installation of the shock pad according to the invention is simple. The porous bonded fibrous matt is simply laid (e.g. from the roll) on the prepared site, with the porous backing (if any) face downwards, and sand is then deposited thereon and brushed or otherwise worked in until the matt is fully sand filled; the synthetic sports turf is then laid over the finished shock pad. The granularity of the sand employed is selected to help provide the required playing characteristics of the turf, to avoid panning, to give good drainage and correct water swelling characteristics. Whilst reference is made above to a sand fill for the bonded fibrous matt, and whilst sand is the most readily available material for use as such filler, sand substitutes could of course be employed within the scope of the invention. Additives may be incorporated in the shock pad according to the invention (in the sand and/or in the fibrous matt) to combat biodegradation of the shock pad and/or to deter attack on it by animals such as rodents, insects etc. CLAIMS

1. A shock pad suitable for use as an underlay for synthetic sports turf and comprising a substantially uniform resiliently compressible porous matt of an open tangle of substantially randomly extending fibres bonded at at least some points of contact, and sand filling the matt.

2. A shock pad for synthetic sports turf, the shock pad being substantially as hereinbefore described.