A pen for cosmetic, writing, drawing, sketching and/or marking purposes includes an inner part and an outer part, wherein at least a portion of the inner part is accommodated in the outer part and is fastened therein. A fastening device between the inner part and the outer part serves to fasten the inner part to the outer part, wherein the fastening device is elastically deformable and is deformed in the installed state against its elastic restoring force. The fastening device is supported between the inner part and the outer part by the elastic restoring force to fasten the inner part to the outer part.

Provided is a writing tool comprising a clip composed of a wire rod, wherein the writing tool is capable of allowing a user to raise the clip without manipulation with both hands. The writing tool 1 comprises a tool body 7 extending in a longitudinal direction, and a clip member 8 composed of a wire rod and held by a lateral portion of the tool body 7, wherein a longitudinal intermediate portion 8B of the clip member 8 is held by the lateral portion of the tool body 7, and the clip member 8 is biased toward the tool body 7 so as to cause a longitudinal fore-end portion 8A of the clip member 8 to come into contact with the tool body 7, and wherein the writing tool is configured such that, when a back-end portion 8C of the clip member 8 is pushed toward the tool body 7, the fore-end portion 8A of the clip member 8 is swung to be spaced apart from the tool body 7.

A thermochromic ink writing instrument comprising a body extending along an axis, the body having a first end and a second end opposed to the first end along the axis, the first end being provided with a writing tip and with an eraser, wherein the writing tip is fed with thermochromic ink, wherein the writing tip is fixed with regard to the body and the eraser is movable along the axis with regard to the body, and the thermochromic ink writing instrument further comprising a helical-cam propelling mechanism configured to move the eraser along the axis between a retracted position and a protruding position.

An erasable ink writing instrument comprising a body extending along an axis, the body having a first end and a second end opposed to the first end along the axis, the first end being provided with a writing tip and with an eraser, wherein the writing tip is fed with erasable ink, wherein the writing tip is fixed with regard to the body and the eraser is movable along the axis with regard to the body, and the erasable ink writing instrument further comprising a helical-cam propelling mechanism configured to move the eraser along the axis between a retracted position and a protruding position. The erasable ink is a peelable ink and the eraser is a friction body.

A writing instrument has a gripping tube rotatably fitted on a front portion of a barrel. At the front portion of the barrel, plural identifying marks having different identification characteristics, such as color, are disposed in parallel in a circumferential direction of the barrel. A window portion is provided in the gripping tube through which is visible an identifying mark selected by rotating the gripping tube relative to the barrel. When the user rotates the gripping tube to the position where the chosen color is visible through the window portion, a locking pawl on the barrel engages with a locking groove at the rear end of the gripping tube to lock the gripping tube in this position. Once locked in position, the gripping tube cannot accidentally rotate thereby preventing a change of colors appearing at the window portion even if the writing instrument is subjected to shock or vibration.

Provided is an ink composition for an aqueous ballpoint pen, the composition having excellent ink discharging performance even if a pen point is exposed for a long period of time. The ink composition for an aqueous ballpoint pen according to the present invention is characterized by containing at least from 1 to 35 mass % of titanium oxide having an average particle size of greater than 0.1 μm and smaller than or equal to 1 μm, and from 1 to 35 mass % of non-tacky urethane particles having an average particle size from 0.1 to 6 μm.

There is a compound represented by the following formula (I):

##STR00001##

in which R1 and R2, identical or different, represent a C.sub.2-C.sub.30 alkyl group, a C.sub.2-C.sub.30 alkenyl group, a C.sub.2-C.sub.30 alkynyl group, or a C.sub.2-C.sub.30 alkoxy group, the alkyl, alkenyl, alkynyl, or alkoxy groups being optionally substituted with at least one hydroxy, halogen, amino, C.sub.1-C.sub.8 alkyl, or C.sub.1-C.sub.8 alkoxy group, as a temperature change regulating agent in a thermochromic ink composition. There also are thermochromic pigment microcapsules having a compound of formula (I) according to the disclosure, to ink compositions having such thermochromic pigment microcapsules, and to writing instruments comprising such ink compositions.

There is a compound represented by the following formula (I):

##STR00001##

in which R1 and R2, identical or different, represent a C.sub.2-C.sub.30 alkyl group, a C.sub.2-C.sub.30 alkenyl group, a C.sub.2-C.sub.30 alkynyl group, or a C.sub.2-C.sub.30 alkoxy group, the alkyl, alkenyl, alkynyl, or alkoxy groups being optionally substituted with at least one hydroxy, halogen, amino, C.sub.1-C.sub.8 alkyl, or C.sub.1-C.sub.8 alkoxy group, as a temperature change regulating agent in a thermochromic ink composition. There also are thermochromic pigment microcapsules having a compound of formula (I) according to the disclosure, to ink compositions having such thermochromic pigment microcapsules, and to writing instruments comprising such ink compositions.

A thermochromic writing instrument including a writing body, storing a thermochromic ink therein, stored in a barrel; an operation body provided in the barrel to be operated to longitudinally move the writing body; a nib of the writing body configured to be capable of appearing from a front end of the writing instrument, wherein the writing instrument 1 further includes a friction unit, for rubbing handwriting in the thermochromic ink and capable of thermally changing the color of the handwriting by frictional heat generated at that time, and at least one clip body as the operation body, the friction unit 10 is provided at a rear end of the barrel, and the clip body is provided in an area other than the rear end of the barrel.

Provided are an oil-based ink composition for writing utensils, a writing utensil using the same, and an airbrush unit using the same. The oil-based ink composition for writing utensils has good writing properties on writing surfaces of various materials and improved scratch resistance to scratches repeated or to scratches with stronger force on a marking after writing. The subject oil-based ink composition for writing utensils contains at least an aluminum pigment, a colorant, a resin, an organic solvent, and a polydimethylsiloxane, the polydimethylsiloxane having polyether-modifying groups at both ends, and a total number of hydroxyl groups on the polyether-modifying groups being 3 or greater.