Synthetic grass playing field surface

DETAILED DESCRIPTION Referring to the drawings, the playing field surface 10 comprises a stabilized base or support surface 11 covered by an underpad 12, upon which a synthetic grass-like, pile carpet is laid.
A sand-like granule filling 14 in-fills the carpet to a substantial depth as indicated by the dotted line 14a in FIG.
1.
The carpet has a carpet base sheet 15 which is preferably formed of a woven sheet of suitable plastic material such as polypropylene, nylon or the like commercially available materials.
Fibers 16 form the piles of the carpet.
These fibers are made of U-shaped, double bent strands 17 whose bights 18 are looped through the carpet base sheet.
The bight portions extending beneath the carpet base sheet form short welts 20.
These welts are aligned into parallel, undulating, sinusoidal curved rows 21.
Each welt extends transversely to its row.
The adjacent welts 20 in each row are parallel and slightly offset relative to each other.
Also, they are closely spaced together, as for example, a 1/8 inch spacing.
However, the rows themselves are spaced further apart, as for example, 1/4 inch apart or about double or more the spacing between the individual welts.
The bottom surface of the carpet base sheet may be coated with a suitable plastic coating 23, such as of urethane or the like commercially available plastic material.
Preferably, such material has a rough or high frictional characteristic, like a rubber surface.
Thus, the coating covers the bights and the rows of bights so that they form rough sinusoidal lines which are bumpy along their length.
By way of example, the fibers used for a suitable pile carpet can be in the range of 5,700-12,000 denier.
The fibers are relatively thick, as for example, a 1.
5 mil thickness for 5,700 denier fiber, 2 mils thick for a 7,600 denier fiber, 2.
6 mils thick for a 10,000 denier fiber and 3 mils thick for an approximately 12,000 denier fiber.
A 2.
6 mil thick, 10,000 denier fiber made of polypropylene is preferable.
However, other plastics which are commercially available and have the necessary characteristics, such as nylon and some of the polyesters, can be used likewise