Embodiments of the invention are directed to a roller ball marking instrument for use with paint, a method for assembling the roller ball marking instrument, and a system for delivering paint. The body of the marking instrument includes a reservoir for storing paint. The body is coupled to a fibrous roller ball via a retaining ring. The roller balls sits within a partially-enclosed cavity in the center of the retaining ring. A least part of the roller ball protrudes through an opening in the retaining ring. Paint in the reservoir moves first through an opening at one end of the body and then through an open center of the retaining ring. The paint is transferred to the roller ball. The roller ball rotates freely within the cavity of the retaining ring and transfers the paint to a writing surface.

A refill for a ball-point pen has an ink cartridge and a ball, the ball being arranged in a writing tip provided at the front end of the ink cartridge, wherein at least the writing tip of the ink cartridge is made solely of a copper-zinc alloy of the following composition (wt. %): 28.0 to 36.0% Zn, 0.5 to 1.5% Si, 1.5 to 2.5% Mn, 0.2 to 1.0% Ni, 0.5 to 1.5% Al, 0.1 to 1.0% Fe, optionally also up to a maximum of 0.1% Pb, optionally also up to a maximum of 0.2% Sn, optionally also up to a maximum of 0.1% P, optionally also up to a maximum of 0.08% S, the rest being Cu and inevitable impurities, with mixed silicides containing iron, nickel and manganese embedded in the matrix.

A ballpoint pen wherein an outer member (50) covering the outer circumference of a holder (21) covers a section that reaches as far as a narrowed section (23) of the holder (21) and has an outer member tip end portion (51). An ink spreads between the writing ball (30) and the contact section of the writing surface and between the outer member tip end portion (51) and the contact section of the writing surface, in which the writing ball (30) and the outer member tip end portion (51) are in contact with the writing surface at the same time. The relative position of the outer member (50) and the holder (21) can be changed from a holder protruding position to a holder retracted position wherein the writing ball (30) and the tip section of the outer member (50) can be in contact with the writing surface at the same time.

A ballpoint pen 10 includes: a ballpoint pen tip 20 having a writing ball 30 and a holder 21 holding the writing ball 30; a shaft tube 12 to which the rear end part of the ballpoint pen tip 20 is mounted; and ink 40 accommodated in the shaft tube 12. The holder 21 has an ink guiding hole 26 formed from the rear end thereof toward the head end thereof and a ball house 22 formed with the inner circumference near the head end of the holder 21 expanded. The writing ball 30 is formed of a zirconia sintered body with the content of an aluminum element being less than 0.1 weight %, and the ink 40 contains inorganic particles 41.

A writing tip assembly for dispensing a free-flowing low-viscosity ink from a writing instrument may include a micro-spring, a writing ball configured to transfer ink to a substrate, and a second ball between the writing ball and the micro-spring. The second ball is configured to transfer ink to the writing ball. A writing instrument for dispensing a free-flowing low-viscosity ink includes an ink reservoir, the writing tip assembly, and a feeder fluidically coupling the ink reservoir to the writing tip assembly.

A system may include a writing instrument. The writing instrument may include a ceramic writing ball. The ceramic writing ball may include, relative to the total weight of the ceramic writing ball, about 1.0 wt.-% to about 14.6 wt.-% of one or more metal oxides selected from Y.sub.2O.sub.3, HfO, MgO, CaO and/or Ce.sub.2O.sub.3, and about 0.15 wt.-% to about 3.0 wt.-% Al.sub.2O.sub.3, and ZrO.sub.2 as balance.

A writing tip assembly for dispensing a free-flowing low-viscosity ink from a writing instrument may include a micro-spring, a writing ball configured to transfer ink to a substrate, and a second ball between the writing ball and the micro-spring. The second ball is configured to transfer ink to the writing ball. A writing instrument for dispensing a free-flowing low-viscosity ink includes an ink reservoir, the writing tip assembly, and a feeder fluidically coupling the ink reservoir to the writing tip assembly.

The present technology relates to a writing instrument such as a pen or stylus, that is capable of writing contemporaneously in different characteristics, such as color and visual appearancethat is, without the need to switch out different cartridges to write in different characteristics; as well as to a writing instrument having multiple nibs, where the multiple nibs can be used to write on a substrate contemporaneously. A writing instrument herein can be configured to write at a substantially perpendicular angle to the substrate, or slightly angled for ease of a user's hand position. A writing instrument that encompasses both electronic and manual (ink) features is also contemplated.