| 摘要 |
<p>A stripe is applied to flexible thermoplastic tubing by advancing the tubing adjacent to a nozzle which deposits a striping liquid in a continuous band on the tubing, drying the deposited liquid, and heating to fuse the dried deposit. The tubing which may be of cellulose ester, a vinyl resin such as vinyl chloride polymerized alone or with a minor proportion of vinyl acetate, vinylidene chloride or an acrylic ester, is plasticized for flexibility. The striping liquid may contain the same resin as the base material and the same amount of plasticizer. The tubing may be freshly extruded from a heated die, the residual heat in the tube being used to evaporate the solvent. The fusion of the stripe may be effected by applying a small flame. The striping liquid may comprise polyvinyl chloride in methyl ethyl ketone with a plasticizer and colouring matter. Alternatively, a dispersion of polyvinyl chloride in tricresyl phosphate, containing a non-solvent thinner such as hexane, may be used, or an emulsion polymer of vinyl chloride and vinylidene chloride containing a plasticizer and colouring matter. A sinuous stripe may be formed by oscillating the nozzle.</p> |
