| 摘要 |
<p>The unit is composed of a core of mineral or expanded resin, which is treated with a bonding agent and then surfaced witha hardenable synthetic resin coating. The composite unit is formed with its surface in contact with a matrix defining its surfacing shape and finish. The mechanical and water resistance of the polymeric surface layer is conferred on the composite unit and makes possible the use of rough or polyhedral surfaces. The composite material is easily and economically made in a mould. The core material is a mineral e.g. concrete or plaster or an expanded plastic. The surface layer is pref. a hardenable resin applied in a plastic or pasty form. The bonding agent is pref. a synthetic polymerisable material e.g. a thixotropic epoxide resin which may be applied with a spray gun.</p> |
