Patent EA-002615-B1 (EA)
Title: Process for laying synthetic grass
Inventor: PREVOST JEAN
IPC: E01C13/00
Filed: 1999-08-03
Abstract: 1. A synthetic grass turf assembly for installation on a supporting substrate to provide a game playing surface, the turf assembly comprising: a pile fabric with a flexible sheet backing (1) and a plurality of upstanding synthetic ribbons (2) of a selected length, representing grass blades, extending upwardly from an upper surface of the backing; and an infill layer (3) of particulate material disposed interstitially between the upstanding ribbons (2) upon the upper surface of the backing (1) and of a depth less than the length of the ribbons (2), the particulate material selected from the group consisting of: hard and resilient granules, the infill layer including: a base course (4) substantially exclusively of hard granules disposed upon the top surface of the backing; a middle course (5) of intermixed hard and resilient granules of a selected relative weight ratio, disposed upon the base course (4); and a top course (6) substantially exclusively of resilient granules disposed upon the middle course (5), an upper portion (7) of the synthetic ribbons extending upwardly from a top surface of the top course. 2. A synthetic grass turf assembly according to claim 1 wherein the relative weight ratio of hard to resilient granules is greater than 2 to 1. 3. A synthetic grass turf assembly according to claim 1 wherein the hard granules are sand particles of size ranging between 14 to 70 U.S. screen mesh standard. 4. A synthetic grass turf assembly according to claim 3 wherein the size of sand particles range between 20 to 50. 5. A synthetic grass turf assembly according to claim 3 or 4 wherein the sand has been washed to remove substantially all fine particles below size 70 mesh. 6. A synthetic grass turf assembly according to claim 1 wherein the resilient granules are crumb rubber particles of size ranging between 10 to 30 U.S. screen mesh standard.7 7. A synthetic grass turf assembly according to claim 2 wherein the middle course (5) weight ratio is in the order of 3 to 1. 8. A synthetic grass turf assembly according to claim 1 wherein the top course (6) has an installed unit weight of up to 2,9 kg per square meter of top surface area. 9. A synthetic grass turf assembly according to claims 1 to 8 wherein the upper portion (6) of the synthetic ribbons (2) is fibrillated on site. 10. A synthetic grass turf assembly according to claims 1 to 8 wherein the synthetic ribbons each comprise multiple fibres with a downwardly curved upper portion. 11. A synthetic grass turf assembly according to claims 1 to 10 wherein the upper portion of the synthetic ribbons (2) extends upwardly 6,35-25,40 mm from the top surface of the top course (6). 12. A synthetic grass turf assembly for installation on a supporting substrate to provide a game playing surface, the turf assembly including: a pile fabric with a flexible sheet backing (1) and a plurality of upstanding synthetic ribbons (2) of a selected length, representing grass blades, extending upwardly from an upper surface of the backing (1); and an infill layer (3) of particulate material disposed interstitially between the upstanding ribbons (2) upon the upper surface of the backing (1) and of a depth less than the length of the ribbons, the particulate material selected from the group consisting of hard and resilient granules, characterized in that the infill layer comprises: a second course (5) of intermixed hard and resilient granules, disposed upon the top surface of the backing (1); and a first course (6) substantially exclusively of resilient granules disposed upon the second course (5), an upper portion (7) of the synthetic ribbons extending upwardly from a top surface of the first course. 13. A synthetic grass turf assembly according to claim 12, wherein the distribution of different sizes of hard granules and resilient granules in the second course are substantially equal and range in size between 10 and 70 screen mesh standard. 14. A synthetic grass turf assembly according to claim 12 or 13, wherein the resilient granules are cryogenically ground rubber. 15. A synthetic grass turf assembly according to claim 13 or 14, wherein the size range for hard granules and resilient granules in the second course is between 15 and 30 screen mesh standard. 16. A synthetic grass turf assembly according to any one of claims 13 to 15, wherein the size range for hard granules and resilient granules in the second course is between 10 and 25 screen mesh standard. 17. A synthetic grass turf assembly according to claim 13 or 14, wherein the size range for hard granules and resilient granules in the second course is between 25 and 50 screen mesh standard.