Patent Application
20070249435
A standard tennis court 10 has playing surface 18 that is bordered by base lines 11 on two of the four sides. Base lines 11 intersect at right angles with each of singles side lines 12 and doubles side lines 13. Service lines 14 are between lines 12 and are connected by center service line 15 that is a perpendicular bisector of each of lines 14 and extends under net 16 between each of service lines 14.
Each of lines 11, 12, 13, 14, and 15 are boundary lines and are similarly treated. In one preferred embodiment, the court is treated as follows:
To the outside of Baselines 11, apply the receiving composition approximately 6 inches outward from the line (see
Next to service lines 14, apply the receiving composition approximately 6 inches outward from the line (i.e. from the service line 14 in the direction of base line 11), service lines 14 are 2 inches wide, receiving composition is applied over service lines 14; and inside service lines 14, receiving composition is applied approximately 4 inches inward.
Next to Center Service line 15—apply the receiving composition on either side of the center line 15 approximately 4 inches and over center line 15 which is typically 2 inches wide.
Singles side lines 12 and Doubles side lines 13 are each treated identically. Apply the receiving composition approximately 6 inches outward from the lines 12 and 13, lines 12 and 13 are 2 inches wide, receiving composition is applied over lines 12 and 13; and inside lines 12 and 13, receiving composition is applied approximately 4 inches inward.
The ball compression itself would be approximately 2 inches when striking the court and therefore the distances given for application of the receiving composition is contemplated as being acceptable to many tennis officials.
These distances were contemplated based on the range of measurement currently utilized by the Cyclops® system. Currently, the Cyclops® system measures 45 cm outside the line service line and 10 cm inside the service line.
As seen in the expansion of
A conventional tennis ball 30 comprises visible seems and fibers. Ball 30 is treated with striking composition 20. Felt ball fibers 25 have fiber dye 26 disposed thereon and further have dye on nodes 27 where fibers 25 typically intersect. Ball 30 may have any part thereof containing striking composition 20. Preferably, a majority of the ball is coated with composition 20.
When ball 30 treated with striking composition contacts a surface treated with a receiving composition, a chemical reaction occurs due to the interaction of the chemical components in each of striking composition and receiving composition, creating a colored impression on the tennis court.
As depicted in
Court surface 18 is typically painted with conventional tennis court paint and coatings as are commonly used and known in the art.
Tennis courts are typically marked with boundary lines 23 standard to the game of tennis. Receiving composition 24 is subsequently disposed on and next to each of lines 11, 12, 13, 14, and 15 on surface 18. Referring to
Examples are given as demonstrative and are not intended to be limiting the scope of the invention.
Most of the examples used a combination of court coating and ball treatment. Objectives were to obtain clear, colorless, non-glossy coatings over conventional tennis court surfaces, distinctive color changes upon impact from tennis balls on the special coating, fast removal of markings on the special coating, and no color change on the tennis balls (or easily reversible color changes).
Schenectady® resin HRJ 40234 (SI Group, Schenectady, N.Y.) 8 ml was combined with Schenectady® 14894 microcapsules 32 ml, and a commercial acrylic latex, Minwax® 1265K 16 ml (approximately 30% solids by weight). This material was brushed onto a dark green tennis court coating, World Class Athletics® #TCP065 (World Class Athletic Surfaces, Leland, Miss.) on a hardboard, target Tennis balls were hit to impact the target and markings were inspected and photographed. Bluish-purplish marks were evident, with oval shapes, indicating that the single-paper system of carbonless carbon paper could provide a marking. However scuffs from tennis shoes also marked the coating the same color, indicating that these commercial materials would not be satisfactory for use as a ball impact marking system. We perceive that a stronger shell might be able to respond differently to ball impacts and shoe impacts and may be workable in a single coating system.
An alkaline latex court coating was made with cornstarch, 5 gm stirred into water, 20 ml. This was added to sodium hydroxide, 2 gm, dissolved in water, 20 ml. The resultant mixture was added to MinWax clear acrylic latex, 15 ml giving a smooth white mixture, easy to brush, but difficult to spray.
Tennis balls were treated with alum mordant and then were contacted with a solution of phenol red dye, 0.5 gm dissolved in denatured alcohol, 10 ml, plus ethoxyethane, 10 ml. The balls turned an orange color, and they were rinsed five times with denatured alcohol to remove superficial dye.
Tennis ball impacts of these balls on a target with the C-2 coating gave discernible, but not distinct marks.
A court coating was made 0.5 grams of Crystal Violet Lactone dye dispersed in Kwal® (Kwal Paint, Denver, Colo.) brand of satin acrylic latex, 15 ml. A tennis ball was treated with a solution of salicylic acid, 32 grams in denatured alcohol, 400 ml (overnight contact, water rinse, dried). The ball was pressed onto the CCP-6 coating and rotated a quarter turn. It made no mark on the coating. A drop of this salicylic acid solution on the coating caused color change to blue, but it was difficult to discern the color difference between the blue and the green background.
A court coating was made with Schenectady 14508 developer, 996 ml, Exsilon® 9 acidic clay pigment (Engelhard Corporation, Iselin, N.J.) 80 gm, dispersed in 25 ml of water, mixed with MinWax® acrylic latex (Minwax Company, Upper Saddle River, N.J.) 12 ml. This off-white coating was applied over TCP065 dark green.
Tennis balls were treated with alum mordant (15 grams/gallon of water, heat at 150° F. for 1 hour, cool, rinse with water, dry) and they were then dyed with a solution of Crystal Violet Lactone (CVL), 5 grams in toluene, 100 ml and ethylene glycol methyl ether, 10 ml. Solution contact was about 15 seconds, followed by baking at 150° F. The tennis balls had very little color change. Where contacted with a drop of salicylic acid solution, the color changed to blue, and microscopic examination showed that the dye was absorbed by the wool fibers of the tennis ball.
The tennis balls with the crystal violet dye were hit at the target with the coating of Example 4, and showed readily discernible marks on the coating (good) and on the tennis balls (undesired, but reversible by exposure to vapors of ammonium hydroxide).
A tan coating was prepared for better discrimination of color change using Schenectady microcapsule dispersion #18894, 64 ml, added to Kwal® brand of satin latex, color #8264D, 12 ml. Tennis balls were prepared using 32 grams of salicylic acid dissolved in 400 ml of denatured alcohol (overnight contact, water rinse, dried).
Ball impacts on this coating gave chalky markings on the target with little color change from the dye.
Schenectady® 4508 developer, 96 ml, was added to MinWax clear acrylic latex, 12 ml, and was applied as a relatively clear, colorless coating over dark green World Class Athletics TCP065 on a panel. Ball treatment was with CVL dye as noted above.
Ball impacts gave dark bluish coloration on both the coating and on the balls. Ball drops from 6-foot height did not give a mark. Dark marks on the ball could be removed by exposure to vapors of ammonium hydroxide.
Schenectady® 4508 developer, 96 ml, was added to MinWax® clear acrylic latex, 12 ml and was applied over dark green TCP065 panel. B-14 ball treatment was made with 5 grams of Malachite Green Lactone dye dissolved in 100 ml of toluene. This solution was sprayed onto a rotating ball held with spiders on a slowly rotating lathe. Spraying was accomplished with an airbrush about 4 inches away from the ball and air pressure about 35 psi. The ball was dried at room temperature and then baked 1 hour at 150° F. A drop of salicylic acid on the ball gave indication of good dye absorption into the felt fibers.
Ball hits on white striping paint were distinct, those on the dark green court were not distinct, and there was little impact marking on the balls. Balls with B-2 treatment were very distinct on white striping paint and fairly distinct on the dark green.
Schenectady® dry resin #HRJ2053, 20 grams, was added to Gemini 160 sanding sealer (a nitrocellulose-based lacquer), 50 ml, diluted with methyl ethyl ketone, 10 ml and diethylhexylphthalate plasticizer 1 ml. This coating had little color or cloudiness and less gloss than CCP-7.
Impact of balls with B-2 treatment gave good color change on this coating.
Salicylic acid, 10 grams, diethylhexylphthalate plasticizer, 1 ml, and Schenectady® solid phenolic resin #2053, 1 gm, were added to 50 ml of denatured alcohol. This gave a hard, non-glossy coating with slightly milky appearance and sparkles from crystals on the surface.
Balls B-2T were made by pre-dyeing tennis ball felt with a solution of Crystal Violet Lactone (CVL), 2 grams, in toluene, 100 ml. The felt had been pre-treated with an alum mordant solution, 15 grams in 1 gallon of water, 1 hour at 150° F., rinsed with water and dried. Tennis balls were then made from this felt by Wilson Sporting Goods, Inc. following their normal fabrication process.
Balls B-18 were made with a spray of dye solution made from Noveon Specialty Yellow #37 (Noveon Inc., Cleveland, Ohio), 2 grams, toluene, 100 ml and propylene carbonate, 2 ml. After spraying, the balls were placed in a ball tube for 1 hour, then they were washed with water to remove the propylene carbonate and they were dried.
Impacts with both ball treatments gave distinctive markings on white striping, and the yellow markings were better on green than the blue markings. The B-18 balls did not have any color change from impact with the CCP-54 coating.
Oxalic acid, 10 gm, Mantrose-Haeuser refined, decolorized shellac #R-49 (Mantrose-Haeuser Company, Westport, Conn.), 1 gm, denatured alcohol, 50 ml. This coating had no gloss, no color, and better initial appearance than above examples. Sprayed onto panel for testing using airbrush.
Treatment on ball was Noveon Specialty Orange #14, 2 grams, xylene, 98 ml, propylene carbonate, sprayed, placed in ball can for 1 hour, washed with water, dried.
Fair color distinction with impact of balls with the B-24 orange and the B-2 blue dyes. Colors faded significantly over 24-hour period.
Oxalic acid, 10 gm, polyvinylpyrollidone K-30, 1 gm, water, 50 ml gave non-glossy, colorless coating, slow dry. B-28 ball treatment used Noveon Magenta #16 dye, 2 gm, xylene, 100 ml, propylene carbonate 2 ml, sprayed onto tennis ball, held in ball can 1 hour, then washed with water and dried.
System gave good color distinction when swatch of B-28 magenta was pressed and turned against the coating, fair color with B-18 yellow and B-24 orange dye treatments.
The above examples all used solvent dyes. Because wool fibers are proteinaceous, they are often dyed commercially with acidic dyes. The following examples use acidified solvents that dye the felt of a tennis ball with the converted color. This provides a means of quickly confirming that a good dye penetration has been accomplished. The dyed felts are then converted back to their intended color by using ammonia vapor or other neutralizing chemicals.
Alkaline chemical added to acrylic court coating, e.g. sodium silicate, sodium tetraborate, either while wet or impregnated after dry, with a phenolphthalein-type color change going from neutral to alkaline.
Because ball marks needed to be removed frequently and quickly (about 90 seconds are available during court direction changes after sets 1, 3, 5 . . .) examples of color removal systems are shown. Treatment with alkali is one means of converting the dye back to its original colorless chemistry, but residual, nonvolatile alkali neutralizes the acidity of the CCP coating and makes it inactive in the case of a second hit by the ball in the area that has been treated. Most of the leuco dyes are soluble in aromatic solvents and other solvents having a relatively low Hildebrand solubility parameter. Dissolution of the dye and wiping to remove it is a means of decolorizing the ball mark, if the solvent does not also dissolve and remove the acid in the special coating.
Ammonium bicarbonate, 10 grams dissolved in 50 ml water+50 ml methanol was sprayed onto ball impact marks and was dried with a heat gun without wiping. Yellow and orange marks disappeared quickly, but blue and magenta colors did not go colorless.
Salicylic acid 10 grams dissolved in denatured alcohol, 50 ml with Schenectady® phenolic resin 2053 1 gm and diethylhexyl phthalate 1 ml was sprayed onto ball impact marks. The marks immediately became more intense by virtue of the additional acidity and dissolution of the dye. The marks were blotted with a soft cloth or paper towel to remove the dissolved dye. The residual coating remained active for marking subsequent ball hits.
A commercial solution of xylene, methanol, acetone and heptane was sprayed onto ball impact marks and it was promptly blotted with a paper towel, removing the marks, but leaving the surface de-activated for subsequent ball hits.
Glacial acetic acid was sprayed onto a ball mark and was blotted dry. Within 20 seconds, the color of the mark disappeared. The preferred remover/activator is formula R-19, a solution of salicylic acid, 10 grams and PVP K-30 1 gram, in methanol 30 ml and toluene 30 ml with 1 ml of lactic acid.
These test were repeated to confirm surface activity after the removing steps.
While the invention has been described in its preferred form or embodiment with some degree of particularity, it is understood that this description has been given only by way of example and that numerous changes in the details of construction, fabrication, and use, including the combination and arrangement of parts, may be made without departing from the spirit and scope of the invention.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/745,284, filed Apr. 21, 2006. The disclosure of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 60745284 | Apr 2006 | US |
