A device for reproducing a color on demand. The device includes a body including a tip and a scanner. The body also includes a control unit, a plurality of ink reservoirs, an ink supply system, a mixing tank and a sensor. The control unit communicates with the scanner and ink supply system to reproduce a desired color that has been scanned.

A device for reproducing a color on demand. The device includes a body including a tip and a scanner. The body also includes a control unit, a plurality of ink reservoirs, an ink supply system, a mixing tank and a sensor. The control unit communicates with the scanner and ink supply system to reproduce a desired color that has been scanned.

A liquid ink instrument, including: a pen body, a writing element mounted on the head of the pen body, an ink absorber mounted at the rear end of the writing element; a fiber ink feeder mounted in the body penetrates the ink absorbing body, the front end in contact with the writing element, the rear end communicated with the ink cartridge; at least one air-liquid balancer in the axial direction, the air-liquid balancer installed between the recited fiber ink feeder and the body; having one or more air-liquid exchange grooves penetrating through the outer circumferential surface; having an overflow groove on a radial surface of the air-liquid balancer, one end contacted to fiber ink feeder, and the other end communicating with air-liquid exchange groove; a gas-free fit or an interference fit adopted between the outer circumferential surface of the fiber ink feeder and the inner wall of the air-liquid balancer.

A ballpoint pen. In the ballpoint pen, an oil-based ballpoint pen ink composition has an ink viscosity with a range of 500 mPa.Math.s to 15000 mPa.Math.s inclusive at 20? C. and a shear rate of 500 sec.sup.?1. A ball has a ball diameter of 0.5 mm or less. A tip distal end portion includes a first swaged portion and a second swaged portion. The first swaged portion has an inclination angle with a range of 90 degrees to 100 degrees inclusive. The second swaged portion is provided closer to a distal end side of a ballpoint pen tip than the first swaged portion and has an inclination angle with a range of 110 degrees to 130 degrees inclusive. An angle of a bottom wall of a ball holding chamber is the same as the inclination angle of the second swaged portion.

A ballpoint pen. In the ballpoint pen, an oil-based ballpoint pen ink composition has an ink viscosity with a range of 500 mPa.Math.s to 15000 mPa.Math.s inclusive at 20? C. and a shear rate of 500 sec.sup.?1. A ball has a ball diameter of 0.5 mm or less. A tip distal end portion includes a first swaged portion and a second swaged portion. The first swaged portion has an inclination angle with a range of 90 degrees to 100 degrees inclusive. The second swaged portion is provided closer to a distal end side of a ballpoint pen tip than the first swaged portion and has an inclination angle with a range of 110 degrees to 130 degrees inclusive. An angle of a bottom wall of a ball holding chamber is the same as the inclination angle of the second swaged portion.

[Problems] An object of the present invention is to provide: a thermochromic color-memory composition which effectively expresses a property of being able to interchangeably memorize and retain colors and which is thus applicable to various fields; and a thermochromic color-memory microcapsule pigment encapsulating the same. [Solution] Provided is a thermochromic color-memory composition including: (a) an electron-donating color-developing organic compound; (b) an electron-accepting compound; and (c) an ester compound represented by the following Formula (1), as a reaction medium which controls color reaction between the component (a) and the component (b): ##STR00001##
(wherein, R represents an alkyl group having 3 to 18 carbon atoms, a cycloalkylalkyl group having 6 to 11 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms or an alkenyl group having 3 to 18 carbon atoms; each X independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 3 carbon atoms or a halogen atom; and each Y independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, an ethoxy group or a halogen atom).

[Problems] An object of the present invention is to provide: a thermochromic color-memory composition which effectively expresses a property of being able to interchangeably memorize and retain colors and which is thus applicable to various fields; and a thermochromic color-memory microcapsule pigment encapsulating the same. [Solution] Provided is a thermochromic color-memory composition including: (a) an electron-donating color-developing organic compound; (b) an electron-accepting compound; and (c) an ester compound represented by the following Formula (1), as a reaction medium which controls color reaction between the component (a) and the component (b): ##STR00001##
(wherein, R represents an alkyl group having 3 to 18 carbon atoms, a cycloalkylalkyl group having 6 to 11 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms or an alkenyl group having 3 to 18 carbon atoms; each X independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 3 carbon atoms or a halogen atom; and each Y independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, an ethoxy group or a halogen atom).

A writing instrument may include an upper pen barrel rotatably connected to a lower pen barrel. A spool valve and fluid reservoirs may be housed in the upper pen barrel. A writing tip secured to the lower pen barrel may be in selective fluid communication with the fluid reservoirs. The upper pen barrel may be rotatable relative to the lower pen barrel of the writing instrument.

A writing instrument may include an upper pen barrel rotatably connected to a lower pen barrel. A spool valve and fluid reservoirs may be housed in the upper pen barrel. A writing tip secured to the lower pen barrel may be in selective fluid communication with the fluid reservoirs. The upper pen barrel may be rotatable relative to the lower pen barrel of the writing instrument.

A writing implement assembly for writing on a writing surface includes an ink dispenser is configured to be attached to a finger. The ink dispenser discharges ink when the ink dispenser engages a writing surface. A grip is removably attached to the ink dispenser to facilitate writing with the ink dispenser.