Stationery

Abstract

To provide stationery capable of suppressing a friction body being separated from a base part of a member.SOLUTION: Stationery includes a member, a friction body, and a first extension wall. The member includes a base part, a first surface provided at the base part, and a shaft part protruding in a protrusion direction from the first surface. The friction body includes a peripheral part which surrounds the shaft part and which comes into contact with the shaft part, and a second surface which is provided at the peripheral part and which comes into contact with the first surface, and it can thermally discolor the handwriting in thermochromic ink by the frictional heat generated by rubbing the handwriting in the thermochromic ink. The first extension wall protrudes in the direction crossing the protrusion direction from one of the shaft part and the peripheral part, at the position being separated in the protrusion direction from the first surface, extends in the protrusion direction, and is fitted in a first recess provided on the other of the shaft part and the peripheral part, at the position being separated in the protrusion direction from the first surface.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Embodiments of the present invention relate to stationery.

Background Art

[0002] Conventionally, writing instruments for writing with thermochromic ink have been known. The handwriting with thermochromic ink can be thermochromically changed to transparent or other colors by frictional heat generated, for example, by rubbing against a friction member.

[0003] The friction member is provided, for example, at the rear end portion in the axial direction of the base portion of a member such as the shaft of the writing instrument. As an example, the friction member is fitted into a hole provided at the rear end portion of the shaft. As another example, the friction member covers the rear end portion of the shaft. In order to prevent the friction member from coming off from the rear end portion of the shaft, for example, a part of the friction member is fitted into a lateral hole provided at the rear end portion.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] When the friction member rubs the handwriting, the friction member rubs the handwriting in a direction (lateral direction) intersecting the axial direction. For this reason, a lateral load acts on the friction member, and the friction member elastically deforms so as to be displaced laterally with respect to the shaft. Due to the elastic deformation, there is a risk that the end of the friction member in contact with the base portion of the shaft will be separated from the base portion of the shaft.

[0006] An example of the problem to be solved by the present invention is to provide stationery that can prevent the friction member from being separated from the base portion of the member.

Means for Solving the Problem

[0007] The stationery according to one embodiment of the present invention includes a member, a friction body, A plurality of a first extended wall, and , a plurality of second extended walls, and has. The member has a base, a first surface provided on the base, and a shaft portion protruding in the protruding direction from the first surface. The friction body has a peripheral portion surrounding the shaft portion and contacting the shaft portion, and a second surface provided on the peripheral portion and contacting the first surface, and can thermochromically change the handwriting of the thermochromic ink by the frictional heat generated by rubbing the handwriting of the thermochromic ink. The A plurality of first extended wall Each of them protrudes in a direction intersecting the protruding direction from one of the shaft portion and the peripheral portion at a position spaced apart from the first surface in the protruding direction, extends in the protruding direction, and fits into a first recess provided in the other of the shaft portion and the peripheral portion at a position spaced apart from the first surface in the protruding direction. The plurality of first extended walls are arranged around the shaft portion with a space therebetween. Each of the plurality of second extended walls projects from one of the shaft portion and the peripheral portion in a direction intersecting the protruding direction, extends in the protruding direction, is connected to the first surface or the second surface, and fits into a second recess provided in the other of the shaft portion and the peripheral portion. The plurality of second extended walls are arranged around the shaft portion with a space therebetween. Each of the plurality of first extended walls is arranged in line with one of the plurality of second extended walls in the protruding direction.

Advantages of the Invention

[0008] According to the present invention, for example, it is possible to prevent the end of the friction body from separating from the shaft.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

MODE FOR CARRYING OUT THE INVENTION

[0010] (First Embodiment) Hereinafter, the first embodiment will be described with reference to FIGS. 1 to 7. In the present specification, the components according to the embodiment and the description of the components may be described in a plurality of expressions. The components and their descriptions are examples and are not limited by the expressions in the present specification. The components may be specified by different names from those in the present specification. Also, the components may be described by expressions different from those in the present specification.

[0011] FIG. 1 is a side view showing a thermochromic writing instrument 10 according to the first embodiment. The thermochromic writing instrument (hereinafter referred to as the writing instrument) 10 of the present embodiment is, for example, a marker and is used to form (write) a handwriting such as a line, a figure, and characters with thermochromic ink. The writing instrument 10 is an example of stationery. The writing instrument 10 is not limited to a marker. For example, the writing instrument 10 may be a ballpoint pen or a multi-core retractable writing instrument. Also, the stationery is not limited to the writing instrument 10 and may be stationery not used for writing. For example, the stationery may be an eraser capable of changing or erasing the handwriting of thermochromic ink. Also, the stationery may be stationery having not only the function of changing or erasing the handwriting of thermochromic ink but also other functions.

[0012] Figure 2 is a cross-sectional view showing the writing instrument 10 of the first embodiment along the line F2-F2 in FIG. 1. As shown in FIG. 2, the writing instrument 10 includes a barrel 11, an ink reservoir 12, a pen tip 13, and a friction member 14. The barrel 11 is an example of a member. Note that the member is not limited to a shaft-shaped member. The friction member 14 may also be referred to as a rubbing member. The writing instrument 10 of the present embodiment is a so-called capped writing instrument and further includes a cap for protecting the pen tip 13. Note that the writing instrument 10 may be other writing instruments such as a click-type, a side-click type, and a rotary type in which the pen tip 13 can be accommodated inside the barrel 11.

[0013] The barrel 11 is formed in a substantially cylindrical shape extending along the central axis Ax. The central axis Ax is a virtual axis located substantially at the center of the barrel 11. In the following description, the direction along the central axis Ax is defined as the axial direction, the direction intersecting (orthogonal in the first embodiment) the central axis Ax is defined as the radial direction, and the direction of rotation around the central axis Ax is defined as the circumferential direction.

[0014] The axial direction includes a rear direction Db and a front direction Df. The rear direction Db is one direction included in the axial direction and is an example of a protruding direction. The front direction Df is the other direction included in the axial direction and is the opposite direction of the rear direction Db. The expressions of front and rear in this specification are for convenience of explanation with the pen tip 13 as the "front" reference. Therefore, the expressions of front and rear in this specification do not limit any conditions such as direction, position, usage mode, priority order, and others.

[0015] The barrel 11 has a shaft body 21. The shaft body 21 is an example of a base portion. The shaft body 21 is formed in a substantially cylindrical shape extending in the axial direction. The end portion 21a of the shaft body 21 in the front direction Df is open. On the other hand, the end portion 21b of the shaft body 21 in the rear direction Db is closed. Note that the end portion 21b of the shaft body 21 may be open. The shaft body 21 has a front shaft 25 and a rear shaft 26. The front shaft 25 may also be referred to as a neck shaft. The rear shaft 26 may also be referred to as a body shaft.

[0016] The front shaft 25 is made of, for example, synthetic resin. Note that the front shaft 25 may be made of other materials. The front shaft 25 is formed in a substantially cylindrical shape extending in the axial direction. The end 25a of the front shaft 25 in the front direction Df and the end 25b of the front shaft 25 in the rear direction Db are open. The end 25a of the front shaft 25 forms the end 21a of the shaft body 21 in the front direction Df.

[0017] The rear shaft 26 is made of, for example, synthetic resin such as ABS resin, polycarbonate (PC) resin, polypropylene (PP) resin, polybutylene terephthalate (PBT) resin, or nylon 6,6. Note that the rear shaft 26 may be made of other materials. Also, the material of the rear shaft 26 may be the same as or different from the material of the front shaft 25.

[0018] The rear shaft 26 is formed in a substantially cylindrical shape extending in the axial direction. The end 26a of the rear shaft 26 in the front direction Df is open. On the other hand, the end 26b of the rear shaft 26 in the rear direction Db is closed. The end 26b of the rear shaft 26 forms the end 21b of the shaft body 21 in the rear direction Db.

[0019] The end 25b of the front shaft 25 in the rear direction Db and the end 26a of the rear shaft 26 in the front direction Df fit into each other. For example, the end 25b of the front shaft 25 in the rear direction Db is fixed inside the end 26a of the rear shaft 26 in the front direction Df by screwing or press-fitting. Thereby, a space 28 opened at the end 21a is formed inside the shaft body 21.

[0020] The ink storage body 12 is accommodated in the space 28 inside the shaft body 21. The ink storage body 12 stores thermochromic ink. The thermochromic ink is, for example, reversible thermochromic ink. The reversible thermochromic ink includes various reversible thermochromic inks such as a heat-decoloring type that decolorizes from a colored state by heating, a color memory retention type that mutually converts between a colored state and a decolorized state and stores and retains them in a specific temperature range, and a heat-coloring type that colors from a decolorized state by heating and returns to a decolorized state by cooling from a colored state.

[0021] The reversible thermochromic ink has, for example, a reversible thermochromic microcapsule pigment as a coloring material. The reversible thermochromic microcapsule pigment contains a reversible thermochromic composition housed in the microcapsules. The reversible thermochromic composition contains at least three components: an electron-donating color-forming organic compound, an electron-accepting compound, and a reaction medium that determines the temperature at which the color-forming reaction between the two occurs. Note that the thermochromic ink is not limited to the above example.

[0022] The pen tip 13 is provided at the end 21a of the shaft body 21 in the forward direction Df. The pen tip 13 is connected to the ink reservoir 12 inside the shaft body 21. The pen tip 13 discharges the thermochromic ink housed in the ink reservoir 12 inside the shaft body 21.

[0023] FIG. 3 is a cross-sectional view showing the periphery of the end 21b of the shaft body 21 in the writing instrument 10 of the first embodiment. FIG. 4 is a cross-sectional view showing the periphery of the end 21b of the shaft body 21 in the writing instrument 10 of the first embodiment along the line F4-F4 in FIG. 3. FIG. 5 is a perspective view showing the end 21b of the shaft body 21 of the first embodiment.

[0024] As shown in FIG. 4, the shaft 11 further has a rear end face 31, an end shaft 32, a plurality of front extension walls 33, a plurality of rear extension walls 34, and a side wall 35. The rear end face 31 is an example of the first face. The end shaft 32 is an example of the shaft portion. The front extension wall 33 is an example of the second extension wall. The rear extension wall 34 is an example of the first extension wall.

[0025] In the present embodiment, the rear end face 31, the end shaft 32, the front extension walls 33, the rear extension walls 34, and the side wall 35 are integrally formed with the rear shaft 26. Note that at least one of the rear end face 31, the end shaft 32, the front extension walls 33, the rear extension walls 34, and the side wall 35 may be formed as a separate part from the other parts.

[0026] The rear end face 31 is provided at the end 21b of the shaft body 21 in the rear direction Db. Note that the end 21b includes not only the end of the shaft body 21 in the rear direction Db but also the periphery of the end. The rear end face 31 is formed, for example, substantially flat and faces the rear direction Db. Note that the rear end face 31 may face in other directions.

[0027] The end shaft 32 protrudes rearward in the direction Db from the rear end face 31. The end shaft 32 of the present embodiment extends axially along the central axis Ax and is formed in a substantially frustum shape that tapers rearward in the direction Db. Note that the end shaft 32 is not limited to this example and may be formed in a cylindrical shape or other shapes. In the present embodiment, the central axis Ax is also a virtual axis located approximately at the center of the end shaft 32.

[0028] The end shaft 32 has an end face 32a and an outer surface 32b. The end face 32a is located at the end of the end shaft 32 in the rearward direction Db. The end face 32a is formed in a substantially circular shape and faces the rearward direction Db. The outer surface 32b is provided between the end face 32a and the rear end face 31. The diameter of the outer surface 32b becomes shorter from the rear end face 31 toward the end face 32a.

[0029] The front extension wall 33 protrudes radially from the outer surface 32b of the end shaft 32. The radial direction is an example of a direction intersecting the axial direction. Note that the front extension wall 33 may protrude from the end shaft 32 in a direction different from the radial direction.

[0030] FIG. 6 is a cross-sectional view showing the writing instrument 10 of the first embodiment along the line F6-F6 in FIG. 4. As shown in FIG. 6, the plurality of front extension walls 33 are arranged around the end shaft 32 with intervals therebetween. In other words, the plurality of front extension walls 33 are arranged with intervals therebetween in the circumferential direction. In the present embodiment, four front extension walls 33 are arranged at equal intervals (every 90°) in the circumferential direction. Note that the number and intervals of the front extension walls 33 are not limited to this example. For example, only one front extension wall 33 may protrude from the end shaft 32.

[0031] As shown in FIG. 4, the front extension wall 33 is formed in a plate shape extending in the axial direction (the rearward direction Db and the forward direction Df). For example, the length of the front extension wall 33 in the axial direction is longer than the length (width) of the front extension wall 33 in the radial direction and longer than the length (thickness) of the front extension wall 33 in the circumferential direction. Note that if the length of the front extension wall 33 in the axial direction is greater than one of the width and thickness of the front extension wall 33, it may be smaller than the other of the width and thickness of the front extension wall 33.

[0032] The end 33a of the front extension wall 33 in the forward direction Df is connected to the rear end face 31. Therefore, it can also be expressed that the front extension wall 33 protrudes from the rear end face 31. The end 33b of the front extension wall 33 in the rearward direction Db faces the rearward direction Db.

[0033] As shown in FIG. 6, each of the plurality of front extension walls 33 has two side faces 33c. The side faces 33c are formed to be substantially flat, are substantially orthogonal to the axial direction, and face in a direction substantially orthogonal to the direction in which the front extension wall 33 protrudes. The two side faces 33c face in opposite directions. Note that the side faces 33c are not limited to this example and may face in other directions.

[0034] As shown in FIG. 3, the rear extension wall 34 protrudes radially from the outer surface 32b of the end shaft 32 at a position spaced rearward in the rearward direction Db from the rear end face 31. The rear extension wall 34 of the present embodiment protrudes from the end shaft 32 at a position spaced rearward in the rearward direction Db also from the front extension wall 33.

[0035] As shown in FIG. 5, the plurality of rear extension walls 34 are arranged around the end shaft 32 with intervals therebetween. In the present embodiment, two rear extension walls 34 are arranged at equal intervals (every 180°) in the circumferential direction. Note that the number and intervals of the rear extension walls 34 are not limited to this example. For example, only one rear extension wall 34 may protrude from the end shaft 32.

[0036] The rear extension wall 34 is formed in a plate shape extending in the axial direction (rearward direction Db and forward direction Df). In the present embodiment, the lengths (length, width, and thickness) of the rear extension wall 34 in the axial direction, radial direction, and circumferential direction are smaller than the lengths of the front extension wall 33 in the axial direction, radial direction, and circumferential direction, respectively. Thereby, for example, the shape and structure of the die parts for forming the shaft 11 become simple, and the formation of the front extension wall 33 and the rear extension wall 34 becomes easier. Note that the dimensions of the front extension wall 33 and the rear extension wall 34 are not limited to this example.

[0037] The rear extension wall 34 is arranged axially along with the corresponding front extension wall 33. In other words, one of the plurality of front extension walls 33 and one of the plurality of rear extension walls 34 overlap at least partially when viewed axially. Note that the positions of the front extension wall 33 and the rear extension wall 34 are not limited to this example.

[0038] As shown in FIG. 3, the end 34a of the rear extension wall 34 in the forward direction Df faces the end 33b of the front extension wall 33 in the rearward direction Db. In the axial direction, the end 34b of the rear extension wall 34 in the rearward direction Db is spaced apart from the end face 32a of the end shaft 32 in the forward direction Df. In other words, the end 34b of the rear extension wall 34 is located in front of the end face 32a of the end shaft 32.

[0039] As shown in FIG. 4, each of the plurality of rear extension walls 34 has two side surfaces 34c. The side surfaces 34c are formed substantially flat, are substantially orthogonal to the axial direction, and face in a direction substantially orthogonal to the direction in which the rear extension wall 34 protrudes. The two side surfaces 34c face in opposite directions. Note that the side surfaces 34c are not limited to this example and may face in other directions.

[0040] The side wall 35 protrudes from the rear end face 31 in the rearward direction Db. The side wall 35 is formed in a substantially cylindrical shape and surrounds the end shaft 32 with a gap. In other words, the end shaft 32 is located inside the side wall 35. The side wall 35 may be formed in other shapes.

[0041] The side wall 35 has an inner surface 35a, an outer surface 35b, and an end face 35c. The end face 35c is an example of an end of the side wall in one direction. The inner surface 35a is formed in a substantially cylindrical shape and faces the outer surface 32b of the end shaft 32 and the plurality of front extension walls 33 with a gap. Therefore, a space 37 is formed between the inner surface 35a of the side wall 35 and the outer surface 32b of the end shaft 32. The inner surface 35a is spaced apart from the front extension wall 33.

[0042] The outer surface 35b is located on the opposite side of the inner surface 35a. The outer surface 35b of the side wall 35 is substantially continuous with the outer surface of the shaft body 21. Note that the outer surface 35b is not limited to this example. The end face 35c is located at the end of the side wall 35 in the rearward direction Db and faces the rearward direction Db.

[0043] As shown in FIG. 5, a plurality of notches 38 are provided in the side wall 35. The notch 38 may also be referred to as a groove. The notch 38 extends forward in the Df direction from the end face 35c of the side wall 35 and opens to the inner surface 35a and the outer surface 35b. In other words, the notch 38 extends in the axial direction. Further, the notch 38 penetrates the side wall 35 in the radial direction.

[0044] As shown in FIG. 3, the end 38a of the notch 38 in the forward Df direction is provided at the same position as the rear end face 31 in the axial direction. Note that the end 38a of the notch 38 may be spaced forward in the Df direction from the rear end face 31 in the axial direction.

[0045] As shown in FIG. 4, in the axial direction, the side wall 35 is shorter than the front extension wall 33. For this reason, the end 33b of the front extension wall 33 in the rearward Db direction is spaced rearward in the Db direction from the end face 35c of the side wall 35 in the axial direction. In other words, the end 33b of the front extension wall 33 is located behind the end face 35c of the side wall 35. Note that the positions of the end 33b of the front extension wall 33 and the end face 35c of the side wall 35 are not limited to this example.

[0046] As shown in FIG. 5, the side wall 35 further has an inner surface 38b of the notch 38. A plurality of inner surfaces 38b extend forward in the Df direction from the end face 35c of the side wall 35. The inner surface 38b is formed substantially flat, is substantially orthogonal to the axial direction, and faces in a direction substantially orthogonal to the direction in which the notch 38 penetrates the side wall 35.

[0047] Two inner surfaces 38b face each other in the circumferential direction. Note that the inner surface 38b is not limited to this example and may face in other directions. The notch 38 is formed between the two facing inner surfaces 38b.

[0048] The plurality of notches 38 are arranged at intervals around the end shaft 32. In the present embodiment, two notches 38 are arranged at equal intervals (every 180°) in the circumferential direction. Note that the number and intervals of the notches 38 are not limited to this example. For example, only one notch 38 may be provided in the side wall 35.

[0049] The notch 38 is arranged radially with the corresponding front extension wall 33 and rear extension wall 34. In other words, the notch 38 penetrates the side wall 35 in the same direction as the direction in which the corresponding front extension wall 33 and rear extension wall 34 protrude from the end shaft 32. Therefore, one of the plurality of front extension walls 33 and one of the plurality of notches 38 overlap at least partially in the radial direction. Note that the positions of the front extension wall 33, the rear extension wall 34, and the notch 38 are not limited to this example.

[0050] The friction body 14 is made of a material including a synthetic resin (elastomer) having elasticity such as, for example, silicone resin, SBS (styrene-butadiene-styrene copolymer) resin, SEBS (styrene-ethylene-butylene-styrene copolymer) resin, fluororesin, chloroprene resin, nitrile resin, polyester resin, and ethylene propylene diene rubber (EPDM). The material of the friction body 14 may include a plurality of elastomers. Also, the material of the friction body 14 may be a mixture of an elastomer and a synthetic resin with relatively low elasticity. The material of the friction body 14 is a low-wear elastic material that generates less wear debris (shavings) due to wear compared to a high-wear elastic material such as sandpaper. Note that the material of the friction body 14 is not limited to the above examples.

[0051] FIG. 7 is a perspective view showing the friction body 14 of the first embodiment. As shown in FIG. 7, the friction body 14 has a peripheral portion 41, a head portion 42, and a plurality of fitting portions 43. The peripheral portion 41, the head portion 42, and the fitting portions 43 are integrally formed.

[0052] The peripheral portion 41 is formed in a substantially cylindrical shape. As shown in FIG. 4, the peripheral portion 41 surrounds the end shaft 32, the front extension wall 33, and the rear extension wall 34 and contacts the end shaft 32, the front extension wall 33, and the rear extension wall 34. Note that in this specification, contact does not necessarily need to be full-surface contact unless otherwise specified, and at least partial contact is sufficient. The peripheral portion 41 has an inner surface 41a, a first outer surface 41b, a second outer surface 41c, and an intermediate surface 41d.

[0053] The inner surface 41a faces the end shaft 32 and contacts the outer surface 32b of the end shaft 32. The first outer surface 41b and the second outer surface 41c are located on the opposite side of the inner surface 41a. The first outer surface 41b faces the side wall 35 and contacts the inner surface 35a of the side wall 35. The second outer surface 41c is spaced apart from the side wall 35 in the rearward direction Db in the axial direction. The second outer surface 41c is substantially continuous with the outer surface 35b of the side wall 35.

[0054] The intermediate surface 41d is provided between the end of the first outer surface 41b in the rearward direction Db and the end of the second outer surface 41c in the forward direction Df. The intermediate surface 41d faces the forward direction Df and contacts the end surface 35c of the side wall 35.

[0055] A part 41e of the peripheral portion 41 between the inner surface 41a and the first outer surface 41b is disposed in the space 37 between the end shaft 32 and the side wall 35. A part 41e of the peripheral portion 41 surrounds the end shaft 32 and is surrounded by the side wall 35.

[0056] The head 42 is provided at the end of the peripheral portion 41 in the rearward direction Db. The head 42 closes the end of the peripheral portion 41 in the rearward direction Db and covers the end surface 32a of the end shaft 32. The head 42 is formed in a substantially hemispherical shape protruding in the rearward direction Db. Note that the head 42 is not limited to this example.

[0057] As shown in FIG. 6, a plurality of fitting portions 43 project radially from the first outer surface 41b of the peripheral portion 41. The plurality of fitting portions 43 are arranged around the end shaft 32 with an interval therebetween. In the present embodiment, two fitting portions 43 are arranged at equal intervals (every 180°) in the circumferential direction. Note that the number and interval of the fitting portions 43 are not limited to this example. For example, only one fitting portion 43 may project from the first outer surface 41b.

[0058] As shown in FIG. 7, the fitting portion 43 extends in the axial direction. The end of the fitting portion 43 in the rearward direction Db is connected to the intermediate surface 41d of the peripheral portion 41. Therefore, the fitting portion 43 can also be expressed as protruding from the intermediate surface 41d.

[0059] As shown in Fig. 6, the fitting portion 43 fits into the corresponding notch 38. Each of the plurality of fitting portions 43 is formed in a shape corresponding to the notch 38 and has two side surfaces 43a. The side surfaces 43a are formed substantially flat and face in a direction substantially orthogonal to the axial direction. The two side surfaces 43a face in opposite directions. The side surfaces 43a contact the inner surface 38b of the notch 38.

[0060] As shown in Fig. 3, the fitting portion 43 further has an outer surface 43b. The outer surface 43b is exposed to the outside of the writing instrument 10 through the notch 38. The outer surface 43b is substantially continuous with the outer surface 35b of the side wall 35.

[0061] The friction body 14 further has a front end surface 45. The front end surface 45 is an example of the second surface. The front end surface 45 is provided at the end portion 41f of the peripheral portion 41 in the forward direction Df. Note that the end portion 41f includes not only the end of the peripheral portion 41 in the forward direction Df but also the periphery of the end. The front end surface 45 is formed, for example, substantially flat and faces in the forward direction Df. Note that the front end surface 45 may face in other directions.

[0062] The front end surface 45 contacts the rear end surface 31 of the shaft 11. Further, the front end surface 45 is included in a part 41e of the peripheral portion 41 between the inner surface 41a and the first outer surface 41b. For this reason, the front end surface 45 is located in the space 37 between the end shaft 32 and the side wall 35.

[0063] A plurality of front recesses 51 and a plurality of rear recesses 52 are provided in the friction body 14. The front recesses 51 are an example of the second recess. The rear recesses 52 are an example of the first recess. The front recesses 51 and the rear recesses 52 may also be referred to as grooves, depressions, or holes.

[0064] The plurality of front recesses 51 are each a notch that opens to the inner surface 41a and the front end surface 45 of the peripheral portion 41. In other words, the front recess 51 is connected to the front end surface 45. The front recess 51 is recessed radially from the inner surface 41a. The plurality of front recesses 51 are arranged at intervals around the end shaft 32. In the present embodiment, four front recesses 51 are arranged at equal intervals (every 90°) in the circumferential direction. The plurality of front extension walls 33 are each fitted into the corresponding front recess 51. Note that the front recess 51 does not penetrate the peripheral portion 41 in the radial direction. For this reason, the peripheral portion 41 surrounds the front extension wall 33.

[0065] As shown in FIG. 6, the peripheral portion 41 further has an inner side surface 51a of the front recess 51. The plurality of inner side surfaces 51a extend rearward in the direction Db from the front end surface 45. The inner side surface 51a is formed substantially flat, is substantially orthogonal to the axial direction, and faces in a direction substantially orthogonal to the direction in which the front recess 51 is recessed. Two inner side surfaces 51a face each other in the circumferential direction. The front recess 51 is formed between the two opposing inner side surfaces 51a. The inner side surface 51a contacts the side surface 33c of the corresponding front extension wall 33.

[0066] As shown in FIG. 3, the plurality of rear recesses 52 are each a depression that opens to the inner surface 41a of the peripheral portion 41 at a position spaced rearward in the direction Db from the rear end surface 31 of the shaft 11 and the front end surface 45 of the friction body 14. The rear recess 52 is recessed radially from the inner surface 41a. The plurality of rear recesses 52 are arranged at intervals around the end shaft 32. In the present embodiment, two rear recesses 52 are arranged at equal intervals (every 180°) in the circumferential direction. The plurality of rear extension walls 34 are each fitted into the corresponding rear recess 52.

[0067] As shown in FIG. 4, the peripheral portion 41 further has an inner side surface 52a of the rear recess 52. The plurality of inner side surfaces 52a extend in the axial direction. The inner side surface 52a is formed substantially flat, is substantially orthogonal to the axial direction, and faces in a direction substantially orthogonal to the direction in which the rear recess 52 is recessed. Two inner side surfaces 52a face each other in the circumferential direction. The rear recess 52 is formed between the two opposing inner side surfaces 52a. The inner side surface 52a contacts the side surface 34c of the corresponding rear extension wall 34.

[0068] As described above, the front extension wall 33 and the rear extension wall 34 that project radially from the end shaft 32 fit into the front recess 51 and the rear recess 52 of the friction body 14. Further, the fitting portion 43 of the friction body 14 fits into the notch 38 that penetrates the side wall 35 in the radial direction. By each of the front extension wall 33, the rear extension wall 34, and the fitting portion 43 fitting into the corresponding front recess 51, rear recess 52, or notch 38, rotation of the friction body 14 in the circumferential direction with respect to the shaft 11 is restricted.

[0069] Further, the rear extension wall 34 that projects from the end shaft 32 at a position separated rearward in the Db direction from the rear end face 31 fits into the rear recess 52 of the friction body 14. Thereby, the rear extension wall 34 restricts the friction body 14 from coming off the shaft 11 in the rearward Db direction.

[0070] The rear shaft 26 of the shaft body 21 and the friction body 14 are integrally formed, for example, by double-molding. For this reason, the rear end face 31, the end shaft 32, the front extension wall 33, the rear extension wall 34, and the side wall 35 of the shaft 11 contact the friction body 14 with substantially no gap. Note that there may be a gap between the shaft 11 and the friction body 14.

[0071] For example, two members formed by two-color molding are joined, bonded, or adhered to each other depending on the combination of the materials of the two members. In the present embodiment, the rear end face 31, the end shaft 32, the front extension wall 33, the rear extension wall 34, and the side wall 35 and the friction body 14 are not joined, bonded, or adhered. For example, when the rear shaft 26 is made of a PC resin and the friction body 14 is made of an SEBS resin, the rear shaft 26 and the friction body 14 are not joined, bonded, or adhered to each other.

[0072] The rear end face 31, the end shaft 32, the front extension wall 33, the rear extension wall 34, and the side wall 35 and the friction body 14 may be joined, bonded, or adhered to each other. For example, when the rear shaft 26 is made of a PP resin and the friction body 14 is made of an SEBS resin, the rear shaft 26 and the friction body 14 are joined, bonded, or adhered to each other.

[0073] In two-color molding, for example, the rear shaft 26 is molded first, and then the friction member 14 is molded later. When the friction member 14 is molded, the material of the friction member 14 is supplied from a gate communicating with the notch 38 of the side wall 35. Therefore, as shown in FIG. 3, a gate trace 43c is formed on the outer surface 43b of the fitting portion 43. According to such a molding process, for example, the formation of a gate trace on the head 42 of the friction member 14 is suppressed, and thus the appearance of the writing instrument 10 is prevented from being impaired.

[0074] The method of two-color molding of the rear shaft 26 and the friction member 14 is not limited to the above example. Further, the friction member 14 may be molded separately from the rear shaft 26 and attached to the rear shaft 26. However, the friction member 14 can be easily molded, firmly attached to the rear shaft 26, and the appearance of the writing instrument 10 can be prevented from being impaired by being integrally formed with the rear shaft 26 by two-color molding.

[0075] The above writing instrument 10 forms the handwriting of the thermochromic ink by discharging the thermochromic ink from the pen tip 13. Further, the friction member 14 can thermally change the color of the handwriting of the thermochromic ink by the frictional heat generated by rubbing the handwriting of the thermochromic ink. Note that the friction member 14 may thermally change the color of the handwriting of the thermochromic ink formed by a writing instrument different from the writing instrument 10.

[0076] Generally, when the friction member 14 rubs the handwriting, the writing instrument 10 is held by the writer (user) in a posture substantially perpendicular or inclined obliquely to the paper surface P on which the handwriting is formed. In this state, the friction member 14 contacts the paper surface P at the head 42 and is moved substantially parallel to the paper surface P. Therefore, when the friction member 14 rubs the handwriting, a load in a direction intersecting the axial direction acts on the head 42 of the friction member 14. For example, a load Ff in the lateral load direction Dh shown in FIG. 6 acts on the head 42 of the friction member 14.

[0077] In the example of FIG. 6, the lateral load direction Dh is a direction substantially orthogonal to the axial direction. Further, in the example of FIG. 6, the lateral load direction Dh is a direction substantially orthogonal to the side surface 33c of the front extension wall 33, the side surface 34c of the rear extension wall 34, the inner side surface 38b of the notch 38, the side surface 43a of the fitting portion 43, the inner side surface 51a of the front recess 51, and the inner side surface 52a of the rear recess 52. Note that the direction in which the load Ff acts on the friction body 14 that rubs the handwriting is not limited to this example.

[0078] While the load Ff in the lateral load direction Dh acts on the friction body 14 due to friction, the load Fo in the direction opposite to the lateral load direction Dh acts on the shaft 11 by the writer. For this reason, the load Ff acting on the friction body 14 due to friction elastically deforms the friction body 14 so as to be displaced relative to the shaft 11.

[0079] Since the load Ff acts on the head portion 42 of the friction body 14 and the load Fo acts on the shaft 11, the friction body 14 elastically deforms so as to be displaced, for example, in the rotation direction Dr shown in FIG. 4. The rotation direction Dr is a direction that is located between the head portion 42 on which the load Ff acts and the position on the shaft 11 on which the load Fo acts and rotates around a rotation axis that is substantially orthogonal to the axial direction.

[0080] When the friction body 14 is displaced in the approximate rotation direction Dr with respect to the shaft 11, a part 45a of the front end surface 45 of the friction body 14 may be pressed against the rear end surface 31 of the shaft 11, and another part 45b of the front end surface 45 may be separated from the rear end surface 31. However, as will be described below, the writing instrument 10 of the present embodiment can suppress the separation of a part 45b of the front end surface 45 from the rear end surface 31.

[0081] For example, the outer surface 32b of the end shaft 32 supports the inner surface 41a of the peripheral portion 41. Further, the side surface 33c of the front extension wall 33 supports the inner side surface 51a of the front recess 51. Also, the side surface 34c of the rear extension wall 34 supports the inner side surface 52a of the rear recess 52. Further, the inner surface 35a of the side wall 35 supports the first outer surface 41b of the peripheral portion 41. Also, the inner side surface 38b of the notch 38 supports the side surface 43a of the fitting portion 43. The outer surface 32b, the side surfaces 33c and 34c, the inner surface 35a, and the inner side surface 38b each support the friction body 14, thereby restricting the displacement of the friction body 14 with respect to the shaft 11.

[0082] The inner side surfaces 38b of the front extension wall 33, the rear extension wall 34, and the notch 38 each extend in the axial direction. For this reason, the inner side surfaces 38b of the front extension wall 33, the rear extension wall 34, and the notch 38 effectively suppress the elastic deformation of the friction body 14 so as to be displaced in the rotational direction Dr, and thus, it is possible to suppress a part 45b of the front end face 45 from separating from the rear end face 31.

[0083] Also, a part 41e of the peripheral portion 41 including the front end face 45 is accommodated in the space 37 between the end shaft 32 and the side wall 35. In other words, a part 41e of the peripheral portion 41 is held between the end shaft 32 and the side wall 35. For this reason, the end shaft 32 and the side wall 35 effectively suppress the elastic deformation of the friction body 14 so as to be displaced in the rotational direction Dr, and thus, it is possible to suppress a part 45b of the front end face 45 from separating from the rear end face 31.

[0084] As described above, the rear shaft 26 and the friction body 14 of the present embodiment are not joined, coupled, or adhered to each other. For this reason, if the front extension wall 33, the rear extension wall 34, and the side wall 35 are not provided, there is a possibility that a part 45b of the front end face 45 may separate from the rear end face 31. However, the writing instrument 10 of the present embodiment has the front extension wall 33, the rear extension wall 34, and the side wall 35, thereby suppressing a part 45b of the front end face 45 from separating from the rear end face 31.

[0085] When the rear shaft 26 and the friction body 14 are joined, coupled, or adhered to each other, the rear end face 31 and the front end face 45 are joined, coupled, or adhered to each other. However, when the friction body 14 rubs the handwriting, the friction body 14 elastically deforms, so that a load in a direction of separating from each other acts on the rear end face 31 and the front end face 45. Repeated elastic deformation due to friction may cause the rear end face 31 and the front end face 45 to peel off from each other. The end shaft 32, the front extension wall 33, the rear extension wall 34, and the side wall 35 can suppress the peeling of the rear end face 31 and the front end face 45 by suppressing the elastic deformation of the friction body 14 so as to be displaced in the rotation direction Dr.

[0086] In the above first embodiment, the front extension wall 33 and the rear extension wall 34 protrude from the end shaft 32, and the front recess 51 and the rear recess 52 are provided in the peripheral portion 41. However, for example, the front extension wall 33 and the rear extension wall 34 may protrude from the inner surface 41a of the peripheral portion 41, and the front recess 51 and the rear recess 52 may be provided in the end shaft 32. Also in this case, the front extension wall 33 and the rear extension wall 34 can effectively suppress the elastic deformation of the friction body 14 so as to be displaced in the rotation direction Dr, and thus suppress the separation of a part 45b of the front end face 45 from the rear end face 31.

[0087] In the writing instrument 10 according to the first embodiment described above, the shaft 11 has a shaft body 21, a rear end face 31 provided on the shaft body 21, and an end shaft 32 protruding rearward in the rear direction Db from the rear end face 31. The friction body 14 has a peripheral portion 41 that surrounds the end shaft 32 and contacts the end shaft 32, and a front end face 45 that is provided on the peripheral portion 41 and contacts the rear end face 31. The friction body 14 can thermally discolor the handwriting of the thermochromic ink by the frictional heat generated by rubbing the handwriting of the thermochromic ink. Generally, when the friction body 14 rubs the handwriting of the thermochromic ink, a load Ff in a direction (lateral load direction Dh) intersecting the rear direction Db may act on the friction body 14 due to the friction. The load Ff tends to elastically deform the friction body 14 so as to be displaced relative to the shaft 11. At this time, the end shaft 32 supports the friction body 14, but there is a risk that a portion of the friction body 14 that is not supported by the end shaft 32 may be displaced relative to the shaft 11. For example, when the friction body 14 elastically deforms so as to be displaced relative to the shaft 11, the front end face 45 of the friction body 14 may be separated from the rear end face 31 of the shaft 11. However, in the writing instrument 10 of the present embodiment, at a position separated from the rear end face 31 in the rear direction Db, one of the end shaft 32 and the peripheral portion 41 protrudes in a direction intersecting the rear direction Db, extends in the rear direction Db, and fits into a rear recess 52 provided in the other of the end shaft 32 and the peripheral portion 41 at a position separated from the rear end face 31 in the rear direction Db. It has a rear extension wall 34. When the direction in which the rear extension wall 34 protrudes intersects the rear direction Db and the lateral load direction Dh, the rear extension wall 34 can support the friction body 14 in the lateral load direction Dh. Therefore, the writing instrument 10 of the present embodiment can suppress the relative displacement of the friction body 14 with respect to the shaft 11 during the friction of the friction body 14, and thus can suppress the separation of the front end face 45 of the friction body 14 from the rear end face 31 of the shaft 11. Further, a part of the friction body 14 is interposed between the rear end face 31 and the rear extension wall 34. When the friction body 14 tries to come off the shaft 11 in the rear direction Db, the rear extension wall 34 supports the above-mentioned part of the friction body 14 and can suppress the friction body 14 from coming off the shaft 11.

[0088] The front extension wall 33 protrudes in a direction intersecting the rear direction Db from one of the end shaft 32 and the peripheral portion 41, extends in the rear direction Db, and fits into a front recess 51 provided in the other of the end shaft 32 and the peripheral portion 41. The front extension wall 33 is connected to the rear end face 31. Further, the front recess 51 is connected to the front end face 45. Thereby, when the direction in which the front extension wall 33 protrudes intersects the rear direction Db and the lateral load direction Dh, the front extension wall 33 can support the friction body 14 in the lateral load direction Dh. Therefore, the writing instrument 10 of the present embodiment can further suppress the relative displacement of the friction body 14 with respect to the shaft 11 during the friction of the friction body 14, and further suppress the separation of the front end face 45 of the friction body 14 from the rear end face 31 of the shaft 11. Further, the front extension wall 33 can support the friction body 14 in the vicinity of the rear end face 31 and the front end face 45. For this reason, the writing instrument 10 of the present embodiment can further suppress the separation of the front end face 45 of the friction body 14 from the rear end face 31 of the shaft 11 during the friction of the friction body 14.

[0089] The rear extension wall 34 protrudes from the end shaft 32. The rear recess 52 is provided in the peripheral portion 41. Since the rear extension wall 34 protrudes from the end shaft 32 having higher rigidity than the peripheral portion 41, the rigidity of the rear extension wall 34 is increased. Therefore, the rear extension wall 34 can be suppressed from deforming when supporting the friction body 14, and thus the friction body 14 can be stably supported.

[0090] The writing instrument 10 includes a plurality of rear extension walls 34 arranged at intervals around the end shaft 32. Thereby, even when the friction body 14 frictions in a plurality of directions, at least one of the plurality of rear extension walls 34 can support the friction body 14 in the lateral load direction Dh. Therefore, the writing instrument 10 of the present embodiment can suppress the relative displacement of the friction body 14 with respect to the shaft 11 during the friction of the friction body 14, and further suppress the separation of the front end face 45 of the friction body 14 from the rear end face 31 of the shaft 11.

[0091] The writing instrument 10 includes a plurality of front extension walls 33 arranged at intervals around the end shaft 32. Thus, even if the friction body 14 rubs in a plurality of directions, at least one of the plurality of front extension walls 33 can support the friction body 14 in the lateral load direction Dh. Therefore, the writing instrument 10 of the present embodiment can suppress the relative displacement of the friction body 14 with respect to the shaft 11 during the friction of the friction body 14, and further suppress the front end face 45 of the friction body 14 from separating from the rear end face 31 of the shaft 11.

[0092] The shaft 11 has a side wall 35 that protrudes rearward in the rear direction Db from the rear end face 31 and surrounds the end shaft 32 and the peripheral portion 41. The peripheral portion 41 contacts the side wall 35. For this reason, a part 41e of the peripheral portion 41 including the front end face 45 is accommodated in the space 37 between the end shaft 32 and the side wall 35. The side wall 35 can support the part 41e of the peripheral portion 41 in the lateral load direction Dh. Therefore, the writing instrument 10 of the present embodiment can suppress the relative displacement of the friction body 14 with respect to the shaft 11 during the friction of the friction body 14, and further suppress the front end face 45 of the friction body 14 from separating from the rear end face 31 of the shaft 11.

[0093] The side wall 35 has an inner surface 35a facing the end shaft 32 and an outer surface 35b located on the opposite side of the inner surface 35a, and a notch 38 is provided which extends from the end surface 35c of the side wall 35 in the rear direction Db and opens to the inner surface 35a and the outer surface 35b. The friction body 14 has a fitting portion 43 that fits into the notch 38. The notch 38 and the fitting portion 43 penetrate the side wall 35 in a direction intersecting the rear direction Db. For this reason, when the direction in which the notch 38 and the fitting portion 43 penetrate the side wall 35 intersects the rear direction Db and the lateral load direction Dh, the inner surface 38b of the notch 38 can support the fitting portion 43 of the friction body 14 in the lateral load direction Dh. Therefore, the writing instrument 10 of the present embodiment can suppress the relative displacement of the friction body 14 with respect to the shaft 11 during the friction of the friction body 14, and thus can suppress the front end surface 45 of the friction body 14 from separating from the rear end surface 31 of the shaft 11. Further, since the space 37 between the end shaft 32 and the side wall 35 is opened to the outside by the notch 38, for example, when the shaft 11 and the friction body 14 are made by two-color molding, the material of the friction body 14 can be easily filled into the space 37 between the end shaft 32 and the side wall 35.

[0094] The end 38a of the notch 38 in the forward direction Df is provided at the same position as the rear end surface 31 or is spaced apart from the rear end surface 31 in the forward direction Df in the rear direction Db. Thereby, for example, when the shaft 11 and the friction body 14 are made by two-color molding, the remaining of air in the space 37 between the end shaft 32 and the side wall 35 is suppressed.

[0095] The end 33b of the front extension wall 33 in the rear direction Db is spaced apart from the end surface 35c of the side wall 35 in the rear direction Db in the rear direction Db. Thereby, the front extension wall 33 can support the friction body 14 outside the space 37 between the end shaft 32 and the side wall 35. Therefore, the front extension wall 33 can further suppress the relative displacement of the friction body 14 with respect to the shaft 11 during the friction of the friction body 14.

[0096] The pen tip 13 is provided at the end 21a of the shaft body 21 in the forward direction Df and can discharge the thermochromic ink accommodated inside the shaft body 21. That is, a pen tip 13 capable of writing the handwriting of the thermochromic ink and a friction body 14 capable of thermochromically changing the handwriting of the thermochromic ink are provided in one writing instrument 10. Thereby, one writing instrument 10 can form and thermochromically change the handwriting of the thermochromic ink. Also, unlike the case where the friction body 14 is fitted into a hole provided at the end of the shaft 11 in the backward direction Db, since the peripheral portion 41 of the friction body 14 covers the end shaft 32, the end of the shaft 11 in the backward direction Db can be blocked. Therefore, the writing instrument 10 of the present embodiment can omit a member (a middle stopper) that seals the thermochromic ink accommodated inside the shaft body 21.

[0097] The peripheral portion 41 of the friction body 14 is provided around the end shaft 32 of the shaft 11. For this reason, the thickness of the peripheral portion 41 is set to be approximately constant. Therefore, the friction body 14 can be formed by a relatively simple mold, and the occurrence of sink marks in the friction body 14 is suppressed. Also, the end shaft 32 does not require a lateral hole and can suppress a decrease in strength.

[0098] (Second Embodiment) Hereinafter, the second embodiment will be described with reference to FIG. 8. In the description of the following embodiments, components having the same functions as the components already described may be given the same reference numerals as those of the already described components, and the description may be further omitted. Also, a plurality of components given the same reference numerals do not necessarily have all functions and properties in common, and may have different functions and properties according to each embodiment.

[0099] FIG. 8 is a cross-sectional view showing a part of the writing instrument 10 according to the second embodiment. As shown in FIG. 8, the shaft 11 of the second embodiment does not have a side wall 35. For this reason, the peripheral portion 41 of the friction body 14 does not have the first outer surface 41b and the intermediate surface 41d and is not held between the end shaft 32 and the side wall 35.

[0100] However, when a load Ff in the lateral load direction Dh acts on the friction member 14 during friction, the outer surface 32b of the end shaft 32 supports the inner surface 41a of the peripheral portion 41. Further, the side surface 33c of the front extension wall 33 supports the inner side surface 51a of the front recess 51. Also, the side surface 34c of the rear extension wall 34 supports the inner side surface 52a of the rear recess 52. The outer surface 32b and the side surfaces 33c, 34c respectively support the friction member 14 to limit the displacement of the friction member 14 with respect to the shaft 11. Therefore, even without the side wall 35, the writing instrument 10 of the second embodiment can effectively suppress the elastic deformation of the friction member 14 so as to be displaced in the rotational direction Dr, and thus can suppress the separation of a part 45b of the front end face 45 from the rear end face 31.

[0101] In the above description, suppression is defined as, for example, preventing the occurrence of an event, action, or influence, or reducing the degree of an event, action, or influence. Also, in the above description, restriction is defined as, for example, preventing movement or rotation, or allowing movement or rotation within a predetermined range and preventing movement or rotation exceeding the predetermined range.

[0102] The above-described embodiments of the present invention do not limit the scope of the invention, but are merely examples included in the scope of the invention. Certain embodiments of the present invention may be modified, omitted, and added, for example, with respect to at least a part of specific uses, structures, shapes, actions, and effects, without departing from the gist of the invention, compared with the above-described embodiments.

Description of Reference Numerals

[0103] 10... Writing instrument, 11... Shaft, 14... Friction member, 21... Shaft body, 31... Rear end face, 32... End shaft, 33... Front extension wall, 34... Rear extension wall, 35... Side wall, 35a... Inner surface, 35b... Outer surface, 35c... End face, 38... Notch, 41... Peripheral portion, 43... Fitting portion, 45... Front end face, 51... Front recess, 52... Rear recess, Db... Rear direction.

Claims

1. A member having a base, a first surface provided on the base, and a shaft portion protruding in a protruding direction from the first surface; A friction member having a peripheral portion surrounding the shaft portion and contacting the shaft portion, and a second surface provided on the peripheral portion and contacting the first surface, capable of thermochromically changing the handwriting of thermochromic ink by frictional heat generated by rubbing the handwriting of the thermochromic ink; A plurality of first extending walls arranged at intervals around the shaft portion, each protruding in a direction intersecting the protruding direction from one of the shaft portion and the peripheral portion at a position spaced from the first surface in the protruding direction, extending in the protruding direction, and fitting into a first recess provided in the other of the shaft portion and the peripheral portion at a position spaced from the first surface in the protruding direction; A plurality of second extending walls arranged at intervals around the shaft portion, each protruding in a direction intersecting the protruding direction from one of the shaft portion and the peripheral portion, extending in the protruding direction, connected to the first surface or the second surface, and fitting into a second recess provided in the other of the shaft portion and the peripheral portion; Comprising: Each of the plurality of first extending walls is arranged in line with one of the plurality of second extending walls in the protruding direction; Stationery.

2. A member having a base, a first surface provided on the base, and a shaft portion protruding in a protruding direction from the first surface; A friction member having a peripheral portion surrounding the shaft portion and contacting the outer surface of the shaft portion, and a second surface provided on the peripheral portion and contacting the first surface, capable of thermochromically changing the handwriting of thermochromic ink by frictional heat generated by rubbing the handwriting of the thermochromic ink; A first extending wall protruding in a direction intersecting the protruding direction from one of the outer surface of the shaft portion and the peripheral portion at a position spaced from the first surface in the protruding direction, extending in the protruding direction, and fitting into a first recess provided in the other of the outer surface of the shaft portion and the peripheral portion at a position spaced from the first surface in the protruding direction; A second extending wall protruding in a direction intersecting the protruding direction from one of the outer surface of the shaft portion and the peripheral portion, extending in the protruding direction, connected to the first surface or the second surface, and fitting into a second recess provided in the other of the outer surface of the shaft portion and the peripheral portion; Comprising: The member has a side wall protruding in the protruding direction from the first surface and surrounding the shaft portion and the peripheral portion. The side wall has an inner wall surface that faces the outer surface of the shaft portion and contacts the peripheral portion. Stationery.

3. In the protruding direction, the side wall is shorter than the second extended wall. The stationery according to claim 2.

4. A member having a base portion, a first surface provided on the base portion, and a shaft portion protruding in a protruding direction from the first surface. A peripheral portion that surrounds the shaft portion and contacts the outer surface of the shaft portion, and a second surface that is provided on the peripheral portion and contacts the first surface, and is capable of thermochromically changing the handwriting of the thermochromic ink by frictional heat generated by rubbing the handwriting of the thermochromic ink. A friction body. At a position spaced from the first surface in the protruding direction, it protrudes in a direction intersecting the protruding direction from one of the outer surface and the peripheral portion of the shaft portion, extends in the protruding direction, and is provided on the other of the outer surface and the peripheral portion of the shaft portion at a position spaced from the first surface in the protruding direction. At least one first extended wall that fits into the first recess. Comprising. The member has a side wall that protrudes in the protruding direction from the first surface and surrounds the shaft portion and the peripheral portion. The side wall has an inner wall surface facing the outer surface of the shaft portion and an outer wall surface located on the opposite side of the inner wall surface, and a notch that extends from the end of the side wall in the protruding direction and opens to the inner wall surface and the outer wall surface is provided. The peripheral portion contacts the inner wall surface of the side wall. The friction body has a fitting portion that fits into the notch. Stationery.

5. A plurality of the first extended walls arranged at intervals around the shaft portion. Comprising. The notch is arranged in a direction orthogonal to one of the plurality of first extended walls in the protruding direction. The stationery according to claim 4.

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