| 摘要 |
<p>Coating is made by first applying over the base surface an adhesive coating consisting of a resinous binding agent (A) which sticks both to porous concrete and to elastic granulated material. The coating has a viscosity of 50-220 seconds (Ford no. 4 cup) at the moment of application. Before the binding agent sets a thin layer of elastic granules (B) (the min. size of which is > the max. dia. of the substrate pores) is spread over the coating. After the binding agent sets the loose granules are removed, giving an even, thin, pref. single thickness, granule layer. A new layer of binding agent (A) is then applied. Before it sets an elastic granulated material of granule size pref. that of (B) is spread over the layer. After setting of the binding agent, the loose excess granules are removed. The coating lessens the hardness of the porous concrete or asphalt surface. It also provides a surface on which a tennis ball has good impact and bounce properties.</p> |
