GB819297A - Improvements in ball-point pens - Google Patents

Abstract

819,297. Reservoir pens. PAPER MATE MANUFACTURING CO. Aug. 19, 1957, No. 26122/57. Drawings to Specification. Class 146(3) In a ball-point writing unit, including a tubular ink reservoir having an open end and a tip holding a rotatable writing ball at the other end, the ink reservoir and the ball are made from dissimilar metallic materials, and the inside of the reservoir is coated throughout the length thereof with a third metallic material which is chemically non-reactive with the ink and prevents electrolytic action in the unit. Where the ball is of steel and the reservoir tube of brass, the coating inside the reservoir may be of nickel or chromium. The inner surface of the tip in which the ball is housed, and the outer surface of the reservoir, may also be coated with nickel or chromium. The metal coating may be applied by electrodeposition, or by a purely chemical process wherein the metal is deposited by chemical reduction from an aqueous solution. In an inkfilled writing unit, the electrical potential between the steel ball and the nickel plating is negligible and there is no danger of the formation of a skin or layer in the ink reservoir, due to electrolytic action, when the writing unit is stored for long periods. In addition, the nickel plating reduces the tendency of the ink to flow out of the open end of the reservoir tube and to creep toward such open end when the tube is stored for long periods in a horizontal or inverted position.