| 摘要 |
A glass plate having channels extending between its opposite faces, for use in an X-ray image intensifier (see Division Hl), is formed by fusing together a plurality of parallel glass tubes, each of which is coated internally with a glass enamel. A 10 mm. diameter lead glass tube is sprayed externally with a low-melting point enamel, and then coated internally with a glass enamel consisting of the oxides of lead (50% by weight), boron (25%), and bismuth (25%). The enamel is prepared by grinding glass of this composition to a frit, and adding to a solution of nitrocellulose in amyl acetate binder, the tube being filled with this coating solution, and subsequently drained and dried, the binder being removed by heat before the tube is drawn down to 200 microns diameter, during which process the coating is fired. More than one coating may be applied and separately fired, before drawing, to give a final coating thickness of 10 microns. Cut lengths of the drawn tube are fused together by heating at 600 DEG C., the resulting plate being heated in hydrogen at 340 DEG C. for two hours to reduce the coating and render it partially conductive. It may be partially reoxidized, to attain a desired value of conductivity, by immersing the plate in nearly boiling water. |
