JP2009126102A - Thermochromic writing utensil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermochromic writing utensil which increases flexibility in terms of design of the writing utensil, while being able to prevent a surface of a friction body from becoming dirty. <P>SOLUTION: The thermochromic riting utensil 1 includes a shaft tube 2 and a cap 3. A thermochromic ink is stored inside the shaft tube 2, and a pen point 21 is provided at one end of the shaft tube 2. The friction body 4 is stored at a front end portion of the cap 3 so as to be capable of moving in front and back direction. The friction body 4 is capable of thermally discoloring handwriting of the thermochromic ink with a frictional heat generated when the handwriting is frictioned. When the writing utensil is used, in a condition where the cap 3 is mounted on a tail tip portion 22 of the shaft tube 2, the tail tip portion 22 of the shaft tube 2 presses the friction body 4 forward, thereby allowing the friction body 4 to protrude outside from the front end of the cap 3. When the writing utensil is not used, the pressing force in the forward direction provided to the friction body 4 is cancelled by removing the cap 3 from the tail tip portion 22 of the shaft tube 2, thereby allowing the friction body 4 to be retracted inside the cap 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a thermochromic writing instrument incorporating a thermochromic ink. More specifically, a thermochromic ink is contained therein, and a friction body capable of thermally changing the handwriting of the thermochromic ink with frictional heat generated by rubbing the handwriting of the thermochromic ink is provided. It relates to a thermochromic writing instrument.

Conventionally, in a thermochromic writing instrument incorporating a thermochromic ink, Patent Document 1 discloses a configuration in which a friction body for thermally discoloring a handwriting by a thermochromic ink by frictional heat is provided on the top of the cap. The structure provided in the rear end is described.

JP 2004-148744 A

Since the conventional thermochromic writing instrument is always in a state where the friction body protrudes from the top of the cap or the rear end of the shaft cylinder, the appearance design of the writing instrument including the friction body must be set. In addition, the degree of freedom is reduced, and the surface of the friction body may be contaminated with an adhering substance such as dust or dirt, and the paper surface may be soiled during friction.

The present invention is intended to solve the above-mentioned conventional problems, and it is intended to provide a thermochromic writing instrument capable of increasing the degree of freedom in the appearance design of the writing instrument and preventing contamination of the surface of the friction body. is there. In the present invention, “front” refers to the top side of the cap, and “rear” refers to the opening side of the cap that can be attached to the shaft cylinder.

[1] The first invention of the present application is that the shaft cylinder 2 is provided with a nib 21 that contains thermochromic ink therein and can eject the thermochromic ink at one end, and the nib 21 of the shaft cylinder 2. A cap 3 having an opening that can be mounted on the side at the rear end, and a friction body 4 that rubs the handwriting of the thermochromic ink at the rear end and can thermally discolor the handwriting by frictional heat generated at that time; A thermochromic writing instrument comprising a cap 3 that can be attached to the pen tip 21 side and tail end portion 22 of the barrel 2, and a friction body 4 that is movable in the front-rear direction at the front end portion of the cap 3. When the cap 3 is mounted on the tail end portion 22 of the shaft cylinder 2, the tail end portion 22 of the shaft cylinder 2 presses the friction body 4 forward so that the friction body 4 protrudes from the front end of the cap 3 to the outside. By removing the cap 3 from the tail end portion 22 of the shaft cylinder 2, the friction body Pressing forward is canceled, the friction body 4 be made possible immerses (claim 1) and the requirements in the cap 3 against.

In the thermochromic writing instrument 1 according to the first aspect of the present invention, when the writing is used, the friction body 4 can be protruded from the front end of the cap 3 by attaching the cap 3 to the tail end portion 22 of the shaft tube 2. it can. In the thermochromic writing instrument 1 according to the first aspect of the present invention, the cap 3 is removed from the tail end portion 22 of the shaft tube 2 when the handwriting is not used (that is, the cap 3 and the tail end portion 22 of the shaft tube 2 are not attached). Thus, the friction body 4 can be immersed in the cap 3 by releasing the forward pressing of the tail end portion 22 of the shaft tube 2 against the friction body 4. Accordingly, since the friction body 4 does not always protrude to the outside, it is not necessary to set the appearance design of the writing instrument including the friction body 4, and when designing the appearance of the writing instrument (that is, the cap 3 on the pen tip 21 side). This increases the degree of freedom when designing the appearance of the mounted writing instrument in a non-writing use state, and prevents the surface of the friction body 4 from being contaminated with dust, dirt, or other deposits during non-writing use.

[2] In the first invention, when the cap 3 is removed from the tail end portion 22 of the shaft tube 2, the friction body 4 may be immersed in the cap 3 due to the weight of the friction body 4 itself. According to a second aspect of the present invention, in the first aspect of the invention, the elastic body 6 that biases the friction body 4 rearward is accommodated in the cap 3, and at least the cap 3 is removed from the tail end portion 22 of the shaft tube 2. In this state, it is required that the friction body 4 is immersed in the cap 3 by the rearward urging of the bullet body 6 (Claim 2).

In the thermochromic writing instrument 1 of the second invention, the cap 3 is accommodated in the cap 3 at the tail end of the barrel 2 when the writing body 6 for energizing the friction body 4 backward is accommodated in the cap 3. By removing from the end 22, the friction body 4 can be surely immersed in the cap 3 without setting the writing instrument in the pen tip upward state. The state where at least the cap 3 is removed from the tail end portion 22 of the shaft cylinder 2 includes a state where the cap 3 is mounted on the pen tip 21 side.

[3] According to a third invention of the present application, in the second invention, the first inner locking portion 32 capable of contacting the front end of the elastic body 6 is provided on the inner surface of the cap 3, An outer locking portion 53 capable of contacting the rear end of the elastic body 6 is provided on the outer surface, and a second inner locking portion 33 capable of contacting the rear surface of the outer locking portion 53 is provided on the inner surface of the cap 3. (Claim 3) is a requirement.

In the thermochromic writing instrument 1 according to the third aspect of the invention, the front end of the elastic body 6 is abutted and locked to the first inner locking portion 32, and the rear end of the elastic body 6 is the outer locking portion 53. Therefore, the friction body 4 is appropriately biased rearward by the elastic body 6. In the thermochromic writing instrument 1 according to the third aspect of the present invention, the second inner locking portion 33 and the rear surface of the outer locking portion 53 are brought into contact with each other, and the rearward movement of the friction body 4 is prevented. The accommodation state of the friction body 4 is properly maintained. Thereby, the thermochromic writing instrument 1 according to the third aspect of the invention can stably maintain the rearward biasing state of the friction body 4 by the elastic body 6 (for example, a compression coil spring).

In the third invention, the outer locking portion 53 may be integrally formed on the outer surface of the friction body 4 or may be formed by a separate member such as a friction body holder attached to the outer surface of the friction body 4. It may be configured. In the third aspect of the invention, the first inner locking portion 32 and the second inner locking portion 33 may be integrally formed on the inner surface of the cap 3 or on the inner surface of the cap 3. You may comprise by the separate member fixed.

[4] According to a fourth invention of the present application, in the third invention, the friction body 4 is formed of a soft material, the friction body holder 5 holding the outer surface of the friction body 4 is formed of a hard material, and the friction It is a requirement that the outer locking portion 53 is integrally formed on the outer surface of the body holder 5 (Claim 4).

In the thermochromic writing instrument 1 according to the fourth aspect of the present invention, the outer locking portion 53 is integrally formed on the outer surface of the friction body holder 5 made of a hard material. And a positive locking state between the outer locking portion 53 and the second inner locking portion 33 are obtained.

In the fourth invention, the soft material constituting the friction body 4 is preferably a synthetic resin (rubber or elastomer) having elasticity, such as silicone resin, SBS resin (styrene-butadiene-styrene copolymer), SEBS. Examples thereof include resins (styrene-ethylene-butadiene-styrene copolymers), fluorine resins, chloroprene resins, nitrile resins, polyester resins, ethylene propylene diene rubber (EPDM), and the like. The synthetic resin having elasticity constituting the friction body 4 may be made of a low-abrasion elastic material that hardly generates erase residue during friction, rather than a high-abrasion elastic material (for example, an eraser). preferable.

In the fourth aspect of the invention, the front end portion of the friction body holder 5 holds the rear end portion outer surface of the friction body 4 (that is, the rear end portion outer surface of the friction body 4 and the rear end surface of the friction body 4). 51 (for example, a bottomed cylinder part) is formed. In the present invention, the outer locking portion 53 provided on the outer surface of the friction body holder 5 is formed integrally with the outer surface of the holding portion 51 or extends rearward from the holding portion 51, for example. The structure integrally formed in the outer surface of the extension part 52 is mentioned. The hard material constituting the friction body holder 5 may be a synthetic resin (for example, polycarbonate resin, polyester resin, polypropylene resin, polyacetal resin, ABS resin) or metal.

-Thermochromic ink In the present invention, the thermochromic ink is preferably a reversible thermochromic ink. The reversible thermochromic ink is a heat decoloring type that decolors by heating from a colored state, a color memory retaining type that reversibly stores and retains a colored state or a decolored state in a specific temperature range, or from a decolored state Various types such as a heating coloring type that develops color by heating and returns to a decolored state by cooling from the colored state can be used alone or in combination.

The coloring material contained in the reversible thermochromic ink includes conventionally known (a) electron donating color-forming organic compounds, (b) electron-accepting compounds, and (c) color reactions of both. A reversible thermochromic pigment in which a reversible thermochromic composition containing at least the essential three components of a reaction medium for determining the occurrence temperature of the polymer is encapsulated in a microcapsule is preferably used.

In the present invention, as shown in FIG. 5, the shape of the curve plotting the change in the color density due to the temperature change is contrary to the case where the temperature is raised from the lower temperature side than the color change temperature range, and from the higher temperature side than the color change temperature range. The color changes by following a different path depending on the descending state, and the color development state in the low temperature range below the complete color development temperature (t ₁ ) or the color erase state in the high temperature range above the complete color erase temperature (t ₄ ) It is preferable to apply a color memory retention type thermochromic ink that can be stored and retained in a specific temperature range [temperature range between t _{2 and} t ₃ (substantially two-phase retention temperature range)]. In FIG. 5, ΔH indicates a temperature width (ie, hysteresis width) indicating the degree of hysteresis. When the value of ΔH is small, only one of the two states before and after the color change can exist. When the value of ΔH is large, it is easy to maintain each state before and after the color change.

In the present invention, the discoloration temperature of the thermochromic ink friction body 4 due to frictional heat is set to 25 ° C. to 95 ° C. (preferably 36 ° C. to 95 ° C.). That is, in the present invention, the high temperature side discoloration point [complete decoloring temperature (t ₄ )] is set in a range of 25 ° C. to 95 ° C. (preferably 36 ° C. to 90 ° C.), and the low temperature side discoloration point [ It is effective to set the complete color development temperature (t ₁ )] in the range of −30 ° C. to + 20 ° C. (preferably −30 ° C. to + 10 ° C.). Accordingly, it is possible to effectively maintain the color exhibited in the normal state (daily life temperature range), and it is possible to easily change the handwriting by the reversible thermochromic ink with the frictional heat generated by the friction body 4.

The thermochromic writing instrument of the present invention increases the degree of freedom in the appearance design of the writing instrument, and can prevent the surface of the friction body from being contaminated with deposits such as dust and dirt when not used.

An embodiment of the present invention is shown in FIGS.
A thermochromic writing instrument 1 according to the present embodiment includes a shaft cylinder 2 that includes a thermochromic ink inside and a pen tip 21 that can discharge the thermochromic ink at one end, and the pen tip of the shaft cylinder 2. The cap 3 is detachable from the 21 side and the tail end 22.

-Pen tip The pen tip 21 of the shaft cylinder 2 employs a ball-point pen tip that holds a ball rotatably at the front end. In addition to the above, the pen tip 21 may be, for example, a fiber bundle resin processed body, a fiber bundle heat-bonded processed body, a felt processed body, a pipe-shaped pen body, and a fountain pen type plate-shaped pen having a slit at the tip. Body, brush pen body, synthetic resin porous foam, synthetic resin extruded body having an ink guide path in the axial direction, and the like.

- thermochromic ink the thermochromic ink is, the low-temperature side color change point (complete coloring temperature t ₁₎ is set to any temperature in the range of -30 ℃ ~-10 ℃, the high temperature side color change point (complete decoloring temperature A reversible thermochromic ink in which t ₄ ) is set to an arbitrary temperature in the range of 60 ° C. to 80 ° C. and the hysteresis width ΔH is in the range of 40 ° C. to 60 ° C. is employed.

Cap At the rear end of the cap 3, an opening that can be attached to the pen tip 21 side of the shaft tube 2 and the tail end portion 22 of the shaft tube 2 is formed. At the front end of the cap 3, an in / out hole 31 in which the friction body 4 can enter and exit is formed. A friction body holder 5 that holds the friction body 4 is accommodated in the front end portion of the cap 3 so as to be movable in the front-rear direction. Further, a bullet body 6 is accommodated in the cap 3, and the friction body holder 5 including the friction body 4 is always urged rearward by the bullet body 6.

Friction body The friction body 4 can rub the handwriting of the thermochromic ink and thermally discolor the handwriting with frictional heat generated at that time. The friction body 4 is formed of a soft material (for example, a synthetic resin having elasticity such as silicone resin, SBS resin, SEBS resin). The friction body 4 is formed in a columnar shape or a prismatic shape.

Friction body holder The outer surface of the rear end portion of the friction body 4 is held by the friction body holder 5. The friction body holder 5 includes a bottomed cylindrical holding portion 51 that can hold the outer surface of the rear end portion of the friction body 4. The bottomed cylindrical holding portion 51 includes an inner peripheral surface into which the rear end portion outer peripheral surface of the friction body 4 can be press-fitted and a bottom wall with which the rear end surface of the friction body 4 can contact. A cylindrical extension 52 is formed behind the holding part 51, and a hook-like outer locking part 53 is integrally formed on the outer surface of the extension 52. The cylindrical extension 52 is opened rearward, and the pen tip 21 is inserted into the cylindrical extension 52 when the cap 3 is attached to the pen tip 21 side. The friction body holder 5 is formed of a hard material made of synthetic resin (for example, polypropylene resin, ABS resin, polycarbonate resin, etc.).

Cap The cap 3 is formed of a synthetic resin molded body, and a first inner locking portion 32 and a second inner locking portion 33 are integrally formed on the inner surface of the cap 3 at the rear. The The first inner locking portion 32 is formed in a step shape, and the second inner locking portion 33 is formed in a protruding shape. In the present invention, in addition to this, the cap 3 is made of metal, and the first inner locking portion 32 and the second inner locking portion 33 are integrally formed on the inner surface of the metal cap 3. The formed cylindrical body made of synthetic resin may be fixed.

-Bullet body The bullet body 6 comprises a compression coil spring. The front end of the bullet body 6 is locked to the first inner locking portion 32, and the rear end of the bullet body 6 is locked to the front surface of the outer locking portion 53. The friction body holder 5 is always urged rearward. When the cap 3 is not attached to the tail end portion 22 of the shaft cylinder 2, the rear surface of the outer locking portion 53 is set to the second inner locking due to the rearward bias of the elastic body 6 to the friction body holder 5. It is latched by the part 33 and the rearward movement of the friction body holder 5 is prevented.

The operation of the present embodiment will be described.

・ Non-writing use (See Fig. 1 and Fig. 2)
At the time of non-writing use, the cap 3 is attached to the nib 21 side of the shaft cylinder 2. At this time, the friction body holder 5 that holds the friction body 4 is moved rearward by the rear urging of the elastic body 6, and the friction body 4 is immersed in the cap 3. At the same time, the rear surface of the outer locking portion 53 of the friction body holder 5 is locked to the second inner locking portion 33 on the inner surface of the cap 3, thereby preventing the rear movement of the friction body holder 5.

・ When using writing (See Fig. 3 and Fig. 4)
At the time of writing, the cap 3 is removed from the pen tip 21 side of the shaft tube 2 and attached to the tail end portion 22 of the shaft tube 2. At this time, the tail end portion 22 of the shaft cylinder 2 and the frictional body holder 5 (specifically, the rear end of the frictional body holder 5) come into contact with each other, and the rear end of the projectile body 6 is resisted against the rear urging of the shaft cylinder 2. The friction body holder 5 is pressed forward by the tail end 22. As a result, the front end portion of the friction body 4 protrudes outward from the front end of the cap 3. In this state, handwriting of the thermochromic ink can be obtained by the pen tip 21, and the handwriting of the thermochromic ink can be frictionally changed by the friction body 4.

It is a longitudinal cross-sectional view at the time of non-writing use of embodiment of this invention. It is a principal part expanded longitudinal cross-sectional view of FIG. It is a longitudinal cross-sectional view at the time of writing use of FIG. FIG. 4 is an enlarged vertical sectional view of a main part of FIG. 3. It is explanatory drawing which shows the color change behavior of a thermochromic ink.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thermochromic writing instrument 2 Shaft cylinder 21 Pen tip 22 Tail end part 3 Cap 31 Retraction hole 32 1st inner side latching part 33 2nd inner side latching part 4 Friction body 5 Friction body holder 51 Holding part 52 Extension part 53 Outer locking part 6 bullet

Claims (4)

A shaft cylinder containing a thermochromic ink inside and having a pen tip capable of ejecting the thermochromic ink at one end, and an opening that can be mounted on the pen tip side of the shaft cylinder at the rear end, and A thermochromic writing instrument comprising a cap provided with a friction body capable of thermally changing the handwriting of the thermochromic ink by rubbing the handwriting of the thermochromic ink at the front end thereof, A cap can be attached to the tail end, a friction body is accommodated in the front end of the cap so as to be movable in the front-rear direction, and when the cap is attached to the tail end of the axle, the tail end of the axle is By pressing the friction body forward, the friction body protrudes outward from the front end of the cap, and by removing the cap from the tail end portion of the shaft cylinder, the forward pressing against the friction body is released, and the friction body is inside the cap. Thermal change characterized by being able to immerse Sex writing instruments. An elastic body that urges the friction body backward is housed in the cap, and at least the cap is removed from the tail end of the shaft tube, the friction body is immersed in the cap by the backward urging of the elastic body. The thermochromic writing instrument according to claim 1. A cap is provided on the inner surface of the cap so as to be in contact with the front end of the projectile, and an outer latch is provided on the outer surface of the friction body so as to be able to contact the rear end of the projectile. The thermochromic writing instrument according to claim 2, wherein a second inner locking portion capable of contacting the rear surface of the outer locking portion is provided on the inner surface of the outer locking portion. The thermochromic property according to claim 3, wherein the friction body is formed of a soft material, the friction body holder for holding the outer surface of the friction body is formed of a hard material, and an outer engaging portion is integrally formed on the outer surface of the friction body holder. Writing instrument.

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