| 摘要 |
<p>The profiles produced by: (a) removing remnants of extrusion lubricants from the surface of the profile by treatment with a solvent, for pref. chromic acid mixed with 80 to 90 % sulphuric acid; (b) drying the profile in an oven with a high degree of air circulation at 50 degrees C for about 2 mins, (c) giving an undercoating of a material with an acrylic base capable of bonding permanently to the PVC, and of being colour printed; (d) printing the undercoated surface; and (c) giving an undercoating of a material with an acrylic base capable of bonding permanently to the PVC, and of being colour printed; (d) printing the undercoated surface and (e) applying a final coating of a protective lacquer to the printed surface. Cheap and easily manipulated profiles of PVC which due to its sensitivity to ultraviolet light cannot retain colour, can be given a permanent coloured coating. Panels of recycled PVC can be used successfully with corresp. economies.</p> |
