Abstract: The outer surface of an inner cap 3 is fixedly secured to the inner surface of an outer cap 4. In the opened end portion of the inner cap 3, there is formed a rear end shell portion 31 which projects backwardly. On the outer peripheral surface of the rear end shell portion 31, there is provided a ring-shaped outward facing seal portion. In the front end portion of a barrel 6, there is formed a front end shell portion 61 projecting forwardly. In the inner peripheral surface of the front end shell portion 61, there is formed a ring-shaped inward facing seal portion. When a cap 2 is mounted on the pen tip 8 side of the barrel 6, the outward facing seal portion can be closely contacted with the inward facing seal portion in the radial direction.

Abstract: To provide a water-based ballpoint pen with a good feel while writing, which hardly causes the proceeding of ball corrosion with time and can maintain an excellent lubrication performance at writing. A water-based ballpoint pen using a cemented carbide ball comprising tungsten carbide and a metal binder as a writing front end, wherein cobalt and/or nickel are contained in the cemented carbide ball as the metal binder in an amount of 1 to 20% by weight based on the total amount of the ball and which further includes an aqueous ink composition containing a colorant, water, a phosphate ester-based surfactant, and any one or more compounds of a thiadiazole represented by formula (1), 5-mercapto-3-phenyl-1,3,4-thiadiazole-2-thione or a salt thereof, and an oligomer of 2,5-dimercapto-1,3,4-thiadiazole: wherein X and Y each represents any substituent of CH3, NH2, and SM, and M represents any of hydrogen, an alkali metal, an ammonium, and an alkanolamine.

Abstract: To provide a reversible thermal discoloration aqueous ink composition which is capable of suppressing the lightening and deepening of handwriting at the time when a writing implement containing the reversible thermal discoloration aqueous ink composition in the barrel, and particularly, which does not lighten the color of handwriting with time in an erecting state or does not lighten the color of handwriting by the application of vibration at transportation or at the time when it is carried on in an erecting state, as well as a writing implement using the same and a writing implement set.

Abstract: A writing implement with a thermochromic coloring color-memory composition which comprises a homogeneous solubilized mixture of (A) an electron donative coloring organic compound, (B) an electron accepting compound and (C) a reaction medium which controls color reactions of the components (A) and (B), wherein a complete decoloring temperature (T4) of the thermochromic coloring color-memory composition is 50° C. or higher and a coloring starting temperature (T2) of thermochromic coloring color-memory composition is 10° C. or lower regarding the color density-temperature curve, and the thermochromic coloring color-memory composition has color-memory ability at the ordinary temperature range.

Abstract: An drawing toy 1 having a excellent performance in play to which water is applied to form images such as letters or characters, and patterns or designs, which are perceivable as images having brilliance is constituted of an drawable member 2 having a light-transmitting support 3 and provided on the surface thereof a porous layer 4 in which a low refractive index pigment has been made dispersedly fixed to a binder resin and which comes different in transparency between a liquid-absorbed condition and a liquid-non-absorbed condition, and a light source 5 which irradiates the back surface of the drawable member with light. A drawing toy set is constituted of the drawing toy 1 and a water-applying implement 15.

Abstract: A water-based ink composition for a ballpoint pen wherein the initial start of writing and writing over time is good, and no blur in handwriting occur and a stable writing performance can be sustained and good handwriting can be continuously formed. A water-based ink composition for a ballpoint pen dissolving or dispersing a coloring agent in an aqueous medium. The aqueous medium substantially contains no water-soluble organic solvent and is composed of water. The water-based ink composition includes a thickening inhibitor together with a shear thinning viscosity-imparting agent. As the thickening inhibitor, one or two or more are selected from a group of polyalkylene glycol, polypropylene glycol derivatives, polyvinyl alcohol, polyvinyl pyrrolidone, cellulose-based polymer compounds, polymer compounds having a polyalkylene oxide group and/or surfactants having a polyoxyethylene group.

Abstract: A thermochromic coloring color-memory composition which comprises a homogeneous solubilized mixture of (A) an electron donative coloring organic compound, (B) an electron accepting compound and (C) an ester compound represented by the specific formula as a reaction medium which controls color reactions of the components (A) and (B).

Abstract: To provide: a water-discoloring drawing toy which, when a writing utensil or applicator for water adhesion is applied thereto, produces a multicolor image and which eliminates the monotonous production of monochromatic images in a related-art technique and is rich in unexpectedness and changes; and a water-discoloring drawing toy set including this drawing toy.

Abstract: The present invention provides a thermochromic coloring color-memory composition which effectively produce a characteristic that colors can be reversibly memorized and maintained and has applicability to various fields and a thermochromic coloring color-memory microcapsule pigment containing the composition. A thermochromic coloring color-memory composition comprising a homogeneous solubilized mixture of (A) an electron donative coloring organic compound, (B) an electron accepting compound and (C) a compound represented by the following formula (1) as a reaction medium which controls color reactions of the components (A) and (B): wherein X represents any of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, and a halogen atom, m represents an integer of from 1 to 3, and n represents an integer of from 1 to 20.

Abstract: A thermochromic coloring color-memory composition which comprises a homogeneous solubilized mixture of (A) an electron donative coloring organic compound, (B) an electron accepting compound and (C) an ester compound represented by the specific formula as a reaction medium which controls color reactions of the components (A) and (B).

Abstract: Provided are a writing instrument produced at a lower cost than conventional thermochromic writing instruments utilizing frictional heat, slim like a pencil and not bulky because it contains an ink directly in a barrel thereof, and excellent in portability; and a set of the writing instruments. The writing instrument 1 is obtained by directly filling a barrel thereof with an ink 2 which becomes colorless or colored, or undergoes a color change by heating and an ink follower 5 following the ink with its consumption; firmly fixing a writing tip portion 3 to the end of the barrel directly or via a relay member; and disposing a friction body 6 having an elasticity at the rear end portion of the barrel. The writing instrument set has a plurality of the writing instruments respectively different from each other in color tone.

Abstract: There is provided a thermochromic writing instrument containing a thermochromic ink, which is capable of easily changing color of the handwriting of thermochromic ink by rubbing and also being quickly brought into a writing-capable state (pen-tip-projected state) or a stored state (pen-tip-retracted state) even when the user can use only one hand.

Abstract: In a liquid composition for metachromatic members which is to be applied to a metachromatic member having a support and provided thereon a porous layer formed by fixing therein a low refractive index pigment in a disperse state together with a binder resin, the liquid composition has a liquid medium and dissolved and/or dispersed therein a solid matter having a refractive index of from 1.3 to 1.8. Also disclosed is a metachromatic member set having this liquid composition and a metachromatic member. The liquid composition for metachromatic members satisfies permanent preservability of images, having superior density retention and shape retention of images formed in the metachromatic member and being suitable for uses in which impressions of hands, feet and the like are taken and preserved or in which written images or stamped images are preserved.

Abstract: A double-head writing instrument has a barrel having a partition formed inside thereof, first and second ink-tanks provided inside the barrel so as not to communicate each other, first and second ink-retaining members connected with first and second nibs provided on an opening of the first and second ink-tanks, respectively, first and second ink reserved inside first and second ink-reservoirs, respectively. The partition is extended in an axial direction so as that the first and second ink-reservoirs overlap each other in a radial direction, and thickness C of the partition and thickness D of a side wall of the barrel connected with the partition satisfy a relation of 0.2?C/D?2.5.

Abstract: A direct-fluid-supply writing implement has a pentip, an ink occluding element connected to a rear end of the pentip, the ink occluding element including a high-density portion, and a low density portion continuously connected to a rear of the high density portion, an ink tank disposed at rear of the ink occluding element and adapted to directly store ink and pluralities of communicating tubes connecting the ink tank with the ink occluding element, the respective communicating tubes including an opened front end, wherein the front end of the communicating tube and the rear end of the pentip connect with the high-density portion.

Abstract: A color-memorizing photochromic writing instrument, which comprises a writing tip portion connected to a light-shielding tubular member or refill; and a color-memorizing photochromic ink, wherein the ink is prepared by dissolving, dispersing or suspending a diarylethene photochromic compound in a vehicle containing at least a solvent and a binder, wherein the diarylethene photochromic compound is in a coloring state, and a color-memorizing photochromic writing instrument set comprising the writing instrument and a color-changing means.

Abstract: A double-head writing instrument has a barrel having a partition formed inside thereof, first and second ink-tanks provided inside the barrel so as not to communicate each other, first and second ink-retaining members connected with first and second nibs provided on an opening of the first and second ink-tanks, respectively, first and second ink reserved inside first and second ink-reservoirs, respectively. The partition is extended in an axial direction so as that the first and second ink-reservoirs overlap each other in a radial direction, and thickness C of the partition and thickness D of a side wall of the barrel connected with the partition satisfy a relation of 0.2?C/D?2.5.

Abstract: A color-change laminate in which a color tone derived from a porous layer is visually perceived in a dry state and a metallic lustrous property is visually perceived in a liquid-absorbed state of the porous layer caused by water application is excellent in luminance and which satisfies both of changing properties and decorative properties in the dry state and in the liquid-absorbed state. A color-change laminate includes a support having a metallic lustrous property and a porous layer provided on the surface of the support. The porous layer includes a low-refractive-index pigment and a transparent metallic lustrous pigment formed by coating a transparent core material with a metal oxide and/or a transparent metallic lustrous pigment having a color-flopping property all fixed onto a binder resin in a dispersed state and is different in transparency in a liquid-absorbed state and in a liquid-unabsorbed state.

Abstract: In a liquid composition for metachromatic members which is to be applied to a metachromatic member having a support and provided thereon a porous layer formed by fixing therein a low refractive index pigment in a disperse state together with a binder resin, the liquid composition has a liquid medium and dissolved and/or dispersed therein a solid matter having a refractive index of from 1.3 to 1.8. Also disclosed is a metachromatic member set having this liquid composition and a metachromatic member. The liquid composition for metachromatic members satisfies permanent preservability of images, having superior density retention and shape retention of images formed in the metachromatic member and being suitable for uses in which impressions of hands, feet and the like are taken and preserved or in which written images or stamped images are preserved.

Abstract: A thermochromic coloring color-memory composition which comprises a homogeneous solubilized mixture of (A) an electron donative coloring organic compound, (B) an electron accepting compound and (C) an ester compound represented by the specific formula as a reaction medium which controls color reactions of the components (A) and (B).