A mat which simulates grass and is designed to be used as a teeing-up mat for use in golf training has been developed by Swedish inventors Jan Lindblad and Bo-Roland Olofzon. The mat has been designed to be durable, but also to provide a surface with the general feeling of grass.
When playing golf the club head often penetrates the ground surface to some extent when striking the ball. When this occurs some grass and earth may be dislodged and this divot has to be replaced after the stroke. This permits the surface to heal and it also should prevent permanent damage being done. In the proposed mat the pile yarns are securely anchored to the backing fabric. As the ball is struck part of the pile is pulled from the mat by the club and after some use there is a tendency for the pile to become sparse and for the mat to wear out. One objective of artificial surfaces is to improve durability and strengthen the anchorage of pile to backing. However, as the pile becomes stronger the characteristics of the mat become poorer in terms of play and the similarity with grass diminishes. The inventors argue that in designing teeing-up mats the manufacturers have tended to ignore that grass essentially comprises two layers. The upper layer has relatively soft blades of grass. Beneath this there is a layer comprising earth and grass roots which are harder than the upper surface, but not sufficiently hard to prevent the golf club from penetrating to some extent. Often the bottom of the mat is drenched with a plastic or rubbery compound which serves to protect the pile fibres from being pulled out when struck by the club. The deeper this layer is the further up the pile will it extend and so the harder the mat will become. In the construction proposed (Figure 2) the mat (1) consists of a ground or backing fabric (2) with a pile (3) which is combined with the backing. This pile projects upwards from the backing. The mat is drenched with natural or synthetic rubber which binds the pile in place. The backing fabric is woven, having warp (4) and weft (5) ends and through these the pile is interwoven. The pile consists of alternating rows of cut and loop pile yarns. However, there are two pile heights, one being longer cut (6) while the lower, loop pile (7) provides support for the projecting longer pile. This means that the longer cut pile will be comparatively sparse, while that below is much denser.
This construction is said to behave much like natural grass, while the sub-structure resembles ground or earth. The impact of a club will be more effectively absorbed by this denser mass. The longer pile offers less resistance to the club during a stroke and the lower resistance is said to lessen the force of impact on the binder layer that holds the pile to the ground fabric. This mat can be used for sports other than golf, including pitch-and-putt courses, minigolf and indoor hockey.