A knocking-type writing instrument has a writing refill, such as a pencil lead or an ink cartridge, that is advanced by knocking a knocking member, and an eraser held by an eraser holder disposed at a rear part of the knocking member. When the writing instrument is inclined so that the eraser side faces downward, a control pin provided in the eraser holder and a movable stopper drop by their own weights along a sliding groove of the knocking member. When the control pin drops a predetermined distance and enters a circumferential locking groove provided at a rear end of the sliding groove, detachment of the control pin is prevented by the stopper, and the eraser holder is unable to retract to the inside of the knocking member. In this state, a radial projection on the control pin abuts a rear end face of the knocking holder, whereby the knocking member is locked and can no longer be knocked, and feeding of the writing refill is prevented.

A collapsible dual screwdriver assembly pliers or drive-pliers for short, comprises a pliers and two screwdriver assemblies, where the screwdriver assemblies are individually removably attachable in a stowed position and an extended position. In the stowed position each screwdriver assembly can provide compact storage of the tool as well as function as a portion of a handle for the other screwdriver assembly. In the extended position each screwdriver assembly can be used as an extended handle for the pliers, as well as, function as a multi-bit screwdriver individually.

A collapsible dual screwdriver assembly pliers or drive-pliers for short, comprises a pliers and two screwdriver assemblies, where the screwdriver assemblies are individually removably attachable in a stowed position and an extended position. In the stowed position each screwdriver assembly can provide compact storage of the tool as well as function as a portion of a handle for the other screwdriver assembly. In the extended position each screwdriver assembly can be used as an extended handle for the pliers, as well as, function as a multi-bit screwdriver individually.

A side-knock type mechanical pencil comprising a body with a side-mounted knock button coupled to the body of the mechanical pencil and adapted to slidingly engage with a lead tube with a frustoconical hub for translating the motion of the knock button actuation to linear extension of the lead.

A side-knock type mechanical pencil comprising a body with a side-mounted knock button coupled to the body of the mechanical pencil and adapted to slidingly engage with a lead tube with a frustoconical hub for translating the motion of the knock button actuation to linear extension of the lead.

A writing instrument includes a barrel, a tip, and a cushion spring that elastically supports the tip in the axial direction to the barrel. The cushion spring is formed as one piece by injection molding, the cushion spring includes an aperture on its outer peripheral surface, and a displacement regulating protrusion that protrudes and extends into the aperture along the axial direction. The protrusion prevents the cushion spring from compression beyond a prescribed length.

A writing instrument includes a barrel, a tip, and a cushion spring that elastically supports the tip in the axial direction to the barrel. The cushion spring is formed as one piece by injection molding, the cushion spring includes an aperture on its outer peripheral surface, and a displacement regulating protrusion that protrudes and extends into the aperture along the axial direction. The protrusion prevents the cushion spring from compression beyond a prescribed length.

A hand-held device includes a first portion and a second portion. The first portion is engaged at least in part with the second portion while being movable in translation in an axial direction relative to the second portion. The first portion presents a first distal end while the second portion presents a second distal end opposite from the first distal end in the axial direction. A blocking device is configured to prevent the first portion from moving in translation in the axial direction relative to the second portion only when, considered in the gravity direction, the first distal end is arranged above the second distal end. The blocking device includes a chamber and a ball or the equivalent housed in the chamber.

To provide a reversibly thermochromic aqueous ink composition excellent in dispersion stability of a reversibly thermochromic microcapsule pigment and a writing instrument using the same.

Disclosed is a reversibly thermochromic aqueous ink composition comprising a reversibly thermochromic microcapsule pigment encapsulating a reversibly thermochromic composition comprising (a) an electron-donating color-developing organic compound, (b) an electron-accepting compound, and (c) a reaction medium to determine an occurrence temperature of a coloring reaction of the component (a) and the component (b), and a vehicle comprising water and a specific gravity adjuster selected from the group consisting of an oxyacid belonging to Group 6 having an atomic weight of 90 to 185 or salt thereof.

To provide a reversibly thermochromic aqueous ink composition excellent in dispersion stability of a reversibly thermochromic microcapsule pigment and a writing instrument using the same.

Disclosed is a reversibly thermochromic aqueous ink composition comprising a reversibly thermochromic microcapsule pigment encapsulating a reversibly thermochromic composition comprising (a) an electron-donating color-developing organic compound, (b) an electron-accepting compound, and (c) a reaction medium to determine an occurrence temperature of a coloring reaction of the component (a) and the component (b), and a vehicle comprising water and a specific gravity adjuster selected from the group consisting of an oxyacid belonging to Group 6 having an atomic weight of 90 to 185 or salt thereof.