| 摘要 |
PURPOSE: To largely decrease the production time, the manpower and the material cost by coloring a hydrophilic material in a xerogel state so that a coloring process is included as a part of integrated production process. CONSTITUTION: A plastic material in a xerogel state is prepared. While the material is not hydrated, the pores of the material are impregnated with a soluble vat dye and then an insoluble vat dye is deposited into the pores. The colored hydrophilic plastic material is polished and finished (hydrated to a desired water content) by well-known techniques, and then sterilized, inspected and packaged. Thus, the whole processes can be automatically and efficiently carried out. |
