Disclosed are a knock type direct liquid pen refill assembly and a writing pen. The pen refill assembly comprises an ink cylinder assembly (100), a pen tip (200) and an elastic member (300). An ink guide core (150) is provided in the ink cylinder assembly. The pen tip (200) is arranged at one end of the ink cylinder assembly (100). An ink duct (210) is formed inside and passes through the pen tip (200). A ball member (230) is provided at an ink outlet end of the ink duct (210). The ink guide core (150) partially passes through the ink duct (210), and one end of the ink guide core (150) is abutted against the ball member (230). The elastic member (300) is sleeved at the periphery of the ink guide core (150) and positioned inside the ink duct (210). The elastic member is abutted against the ball member to exert a force, such that the ball member is closely attached to an inner wall of the ink outlet end, the ball member forms sealed contact with the inner wall of the ink outlet, and ink volatilization and leakage are avoided.

A ball point tip comprising a ball holder having an ink conduit and a ball house, a ball accommodated into the ball house and a leaf spring axially disposed between the ball and an axial end of the ink conduit, the leaf spring having a main body and a plurality of tongues extending radially from the main body, ink passages being formed between the tongues in order to fluidly connect the ink conduit and the ball house, wherein the ball holder and the leaf spring are made of plastic and unitary formed.

A writing ball capable of suppressing wear of a ball seat of a ballpoint pen tip and obtaining stable ink outflow, a writing ball that is a sphere, the sphere comprising, at least: a first hard component containing a first metal; a second hard component containing a second metal; and a binding component, the writing ball comprising: a first outer surface from which the first hard component is exposed, the first outer surface being an outermost surface of the sphere; and a recess including, as a bottom surface, a second outer surface from which the second hard component is exposed, the second outer surface being recessed inward from the first outer surface, wherein the first outer surface includes a smooth 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.

There is provided a friction body which is adapted to rub a thermochromic image or handwriting formed on a paper surface by use of thermochromic ink to thermally discolor the thermochromic image or handwriting by frictional heat resultant from rubbing, a thermal conductivity of a friction portion of the friction body is set to be within 0.05 W/(m.Math.K) to 50 W/(m.Math.K).

Provided are: a writing implement in which a joint connecting an ink supply section and a ballpoint pen tip together is configured from three members. The three members configuring the joint are a substantially cylindrical center member, a substantially cylindrical surrounding member formed at the outer periphery of the center member, and an interposing member that is molded by a soft member molded so as to cover the outer periphery of the center member and the surrounding member. An annular gap section is provided between the center member and the surrounding member. The leading end of the ink supply section is fitted into the gap section. The joint is formed by two color molding. The center member and the surrounding member are molded by primary molding, and the interposing member is integrally molded onto the center member and the surrounding member by secondary molding.

Provided are: a writing implement in which a joint connecting an ink supply section and a ballpoint pen tip together is configured from three members. The three members configuring the joint are a substantially cylindrical center member, a substantially cylindrical surrounding member formed at the outer periphery of the center member, and an interposing member that is molded by a soft member molded so as to cover the outer periphery of the center member and the surrounding member. An annular gap section is provided between the center member and the surrounding member. The leading end of the ink supply section is fitted into the gap section. The joint is formed by two color molding. The center member and the surrounding member are molded by primary molding, and the interposing member is integrally molded onto the center member and the surrounding member by secondary molding.

Provided is a ballpoint pen refill including: an ink storage tube made of a synthetic resin and storing an ink thereinside; a ball holder made of a synthetic resin and attached to a distal end of the ink storage tube; a ball pressing rod mounted inside the ball holder; and a writing ball stored in a distal end of the ball holder and having a rear end side held by the ball pressing rod, in which the ball pressing rod includes: a fixing portion fixed to the ball holder; a movable portion slidable in a front-rear direction with respect to the ball holder; a compression portion connecting the fixing portion and the movable portion; and a rearward movement restricting portion protruding from a distal end of the fixing portion and provided with a gap from a rear end of the compression portion.

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 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.