Writing instrument and writing instrument set

Abstract

To provide a writing instrument and a writing instrument set capable of marking a desired place on a paper surface as intended. A method is provided.SOLUTION: A writing instrument comprising a barrel, a first tip member having a writing part for forming a handwriting, and a support part extending in a direction substantially parallel to an extending direction of a front part of the first tip member, wherein a color of a handwriting formed by the first tip member is a color having a complementary color relationship with a color of a colored transparent sheet. Or a writing instrument comprising a barrel, a first tip member having a writing part for forming a handwriting, and a support part extending in a direction substantially parallel to an extending direction of a front part of the first tip member, wherein a color of a handwriting formed by the first tip member is a color having a complementary color relationship with a color of a component for a writing instrument constituting the writing instrument, and the component for the writing instrument has transparency.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a writing instrument and a writing instrument set. [Background technology]

[0002] Conventionally, memorization pen sets have been known that are effective for memorization tasks during study, in which a transparent colored sheet of a specific color (hereinafter sometimes referred to as a "colored transparent sheet") is placed over the area written with a writing instrument, making the area written invisible. A learning tool has been disclosed as a pen set for memorization, which includes a writing implement and a colored transparent film that is a complementary color to the color of the part to be marked by the writing implement (see, for example, Cited Document 1). Using this learning tool, characters that need to be memorized, which are printed in normal black, are filled in with a writing implement using an ink that allows the characters to be seen through, forming colored areas (marking). The characters in the marked area are readable, but if a colored transparent film is placed over the marked area, the characters become black, making it difficult to read, allowing for efficient learning. With such a memorization pen set, it is necessary to mark only the parts that need to be memorized, and if you mark parts that do not need to be memorized, the marked parts will not be visible when the colored transparent sheet is placed over them. However, when marking on a page that is placed in an unstable location or on the pages of a thick book that curves significantly when opened, it can be difficult to mark properly, and the marked part may shift, causing you to unintentionally mark parts that do not need to be memorized. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Microfilm of JP 57-37389 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been made based on the background technology described above, and aims to provide a writing instrument and writing instrument set that can mark desired locations on paper as intended. [Means for solving the problem]

[0005] The writing instrument of the present invention comprises: [1] A barrel and a first tip member having a writing portion for forming handwriting; a support portion extending in a direction substantially parallel to the extension direction of the front portion of the first tip member; A writing instrument comprising: The color of the writing formed by the first tip member is a color that is complementary to the color of the colored transparent sheet.

[0006] The writing instrument of the present invention comprises: [2] A writing instrument according to [1], comprising a second tip member having a writing portion for forming handwriting, wherein the color of the handwriting formed by the second tip member is selected from the group consisting of a color that is complementary to the color of the colored transparent sheet, a color that is homochromatic to the color of the colored transparent sheet, and a constituent color obtained by subtractive color mixing of the color of the colored transparent sheet.

[0007] The writing instrument of the present invention comprises: [3] A barrel, a first tip member having a writing portion for forming handwriting; a support portion extending in a direction substantially parallel to the extension direction of the front portion of the first tip member; A writing instrument comprising: The color of the writing formed by the first tip member is a color that is complementary to the color of the writing instrument parts that make up the writing instrument, and the writing instrument parts are transparent.

[0008] The writing instrument of the present invention comprises: [4] The writing instrument according to [3], wherein the writing instrument part is the support part.

[0009] The writing instrument of the present invention comprises: [5] A writing instrument according to [3] or [4], comprising a second tip member having a writing portion for forming handwriting, wherein the color of the handwriting formed by the second tip member is selected from the group consisting of a color that is complementary to the color of the writing instrument component, a color that is the same color as the color of the writing instrument component, and a component color obtained by subtractive color mixing of the color of the writing instrument component.

[0010] The writing instrument of the present invention comprises: [6] A writing instrument according to [1] or [2], which contains a color-changing ink containing a dye that changes color or loses color through reduction and water, and the color-changing ink is ejected by the first tip member.

[0011] [7] The writing instrument of the present invention comprises: A writing instrument according to any one of [3] to [5], which contains a color-changing ink containing a dye that changes color or fades color through reduction and water, and the color-changing ink is ejected by the first tip member.

[0012] The writing instrument of the present invention comprises: [8] A writing instrument according to [6] or [7], comprising a third tip member having an application portion for applying a color-changing liquid, the color-changing liquid discoloring or erasing the handwriting formed with the color-changing ink.

[0013] The writing instrument of the present invention comprises: [9] A writing instrument as described in any one of [2] or [5] to [7], which has the first tip member at one end of the barrel and the second tip member at one end or the other end.

[0014] The writing instrument of the present invention comprises:

[10] A writing instrument according to any one of [2] or [5] to [9], wherein the writing portion of the first tip member and the writing portion of the second tip member have different shapes.

[0015] The writing instrument of the present invention comprises:

[11] A writing instrument according to [8], which has the first tip member at one end of the barrel and the third tip member at one end or the other end.

[0016] The writing instrument of the present invention comprises:

[12] The writing instrument according to [8] or

[11] , wherein the application portion of the third tip member is larger than the writing portion of the first tip member.

[0017] The writing instrument set of the present invention comprises:

[13] A writing instrument according to any one of [1], [2], [6], or [8] to

[12] ; A colored transparent sheet, A writing instrument set comprising:

[0018] The writing instrument set of the present invention comprises:

[14] A writing instrument according to any one of [6], [9], or

[10] ; an applicator containing a color-changing liquid that discolors or erases handwriting formed with the color-changing ink and including a third tip member having an applicator portion that applies the color-changing liquid; A writing instrument set comprising:

[0019] The writing instrument set of the present invention comprises:

[15] The writing instrument set according to

[14] , further comprising a colored transparent sheet. [Effects of the Invention]

[0020] The present invention provides a writing instrument and writing instrument set that has a support portion that extends in a direction approximately parallel to the extension direction of the front portion of the pen tip, so that the pen tip is stable when writing and can mark desired locations on paper placed in an unstable location or on a curved paper surface as intended. [Brief explanation of the drawings]

[0021] [Figure 1]FIG. 1 is a diagram showing one embodiment of the present invention, and is an external view showing an example of a writing implement. [Figure 2] FIG. 2 is a vertical cross-sectional view of the writing instrument of FIG. [Figure 3] FIG. 3 is a front view of the writing instrument of FIGS. 1 and 10. FIG. [Figure 4] FIG. 4 is a perspective view showing a holding member of the writing implement. [Figure 5] FIG. 5 is a half-cut perspective view showing the holding member. [Figure 6A] 6A is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line AA in FIG. 3. FIG. [Figure 6B] 6B is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line BB in FIG. 3. FIG. [Figure 7A] 7A is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line AA in FIG. 3. FIG. [Figure 7B] FIG. 7B is an enlarged view of the portion marked 7B in FIG. 7A. [Figure 7C] 7C is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line BB in FIG. 3. FIG. [Figure 7D] FIG. 7D is an enlarged view of the portion labeled 7D in FIG. 7C. [Figure 8A] 8A is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line AA in FIG. 3. FIG. [Figure 8B] FIG. 8B is an enlarged view of the portion marked 8B in FIG. 8A. [Figure 8C] 8C is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line BB in FIG. 3. FIG. [Figure 8D] FIG. 8D is an enlarged view of the portion marked 8D in FIG. 8C. [Figure 9A] 9A is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line AA in FIG. 3. FIG. [Figure 9B] FIG. 9B is an enlarged view of the portion marked 9B in FIG. 9A. [Figure 9C] 9C is a view for explaining an example of a process for attaching the tip member and the holding member to the barrel, and is a vertical cross-sectional view corresponding to the line BB in FIG. 3. FIG. [Figure 9D] FIG. 9D is an enlarged view of the portion marked 9D in FIG. 9C. [Figure 10] FIG. 10 is a diagram showing an embodiment of the present invention, and is an external view showing another example of a writing implement. [Figure 11] FIG. 11 is a diagram showing one embodiment of the present invention, and is an external view showing an example of an applicator. DETAILED DESCRIPTION OF THE INVENTION

[0022] An embodiment of the present invention will now be described with reference to the drawings. In the drawings attached to this specification, the scale and aspect ratios have been appropriately changed and exaggerated from those of the actual objects for the sake of ease of illustration and understanding.

[0023] Furthermore, terms used in this specification that specify shapes, geometric conditions, and their degrees, such as "parallel," "orthogonal," and "identical," as well as values ​​of lengths and angles, are not to be construed as being bound by strict meanings, but rather as including a range within which similar functions can be expected.

[0024] In this specification, the direction in which the central axis A of the writing instrument 10 extends (longitudinal direction, up-down direction in a vertical cross section) is referred to as the axial direction da, the direction perpendicular to the axial direction da is referred to as the radial direction, and the direction along the circumference around the central axis A is referred to as the circumferential direction. Along the axial direction da, the side that approaches a writing surface such as a piece of paper when writing (the upper side in a vertical cross section) is referred to as the front, and the side that moves away from the writing surface (the lower side in a vertical cross section) is referred to as the rear. Along the radial direction, the side that approaches the central axis A is referred to as the inside or inner side, and the side that moves away from the central axis A is referred to as the outside or outer side.

[0025] FIG. 1 is a diagram showing one embodiment of the present invention, and is an external view showing an example of a writing instrument 10. FIG. 2 is a longitudinal cross-sectional view of the writing instrument 10. FIG. 3 is a diagram showing the writing instrument 10 as viewed from the front. FIG. 4 is a perspective view showing a holding member 70 of the writing instrument 10. FIG. 5 is a half-cut perspective view showing the holding member 70. In particular, FIG. 5 shows the holding member 70 cut along a plane including the central axis A of the writing instrument 10. FIG. 10 is a diagram showing one embodiment of the present invention, and is an external view showing another example of the writing instrument 10. FIG. 11 is a diagram showing one embodiment of the present invention, and is an external view showing an example of an applicator 100.

[0026] The writing instrument 10 of this embodiment is a memorization pen used for so-called rote learning, for example, by marking characters printed on the paper of a textbook, reference book, notebook, etc., or characters that the user of the writing instrument has written on the paper himself, and then overlaying a colored transparent sheet on the marked area to make the characters difficult to see, allowing the user to memorize the difficult-to-see parts. The form of the writing instrument 10 is not particularly limited, and examples thereof include various writing instruments such as a ballpoint pen, a marking pen (marker), a fountain pen, a brush pen, and a calligraphy pen. A marking pen (marker) or a felt-tip pen is preferred as the form of the writing instrument 10 because it is easy to mark characters. In this embodiment, an example in which the writing instrument 10 is a marking pen will be described. The writing instrument 10 includes a barrel 15, a first tip member 50, and a holding member 70 having a support portion.

[0027] The barrel 15 extends in the axial direction da along the central axis A of the writing instrument 10. Therefore, the central axis of the barrel 15 coincides with the central axis A of the writing instrument 10. The barrel 15 includes a front barrel 20 and a rear barrel 40 attached to the rear end of the front barrel 20.

[0028] The front barrel 20 is a member that forms the front portion of the writing instrument 10. The front barrel 20 has a generally cylindrical shape. The central axis of the front barrel 20 coincides with the central axis A of the writing instrument 10. The rear barrel 40 is a member that forms the rear portion of the writing instrument 10. The rear barrel 40 has a generally cylindrical shape. The central axis of the rear barrel 40 coincides with the central axis A of the writing instrument 10. In this embodiment, the rear barrel 40 is intended to be grasped with the fingers of a user when writing with the writing instrument 10. The rear barrel 40 may include an inner barrel and a grip portion disposed on the outside of the inner barrel. The grip portion is a portion that is held with the fingers of a user when writing with the writing instrument 10. However, this is not limited thereto, and the writing instrument 10 may also be configured so that the user grasps the front barrel 20 to write. In this embodiment, the front barrel 20 is attached to the rear barrel 40 by inserting the rear end portion of the front barrel 20 into the front end portion of the rear barrel 40. For example, front axle 20 may be attached to rear axle 40 by press-fitting the rear end of front axle 20 into the front end of rear axle 40. Alternatively, front axle 20 may be attached to rear axle 40 by a front axle-side convex portion formed on the outer circumferential surface of the rear end of front axle 20 climbing over a rear axle-side convex portion formed on the inner circumferential surface of the front end of rear axle 40 and becoming engaged with said rear axle-side convex portion. A flange 21 is formed on the outer circumferential surface of front axle 20. With front axle 20 attached to rear axle 40, flange 21 may come into contact with the front end of rear axle 40. A cap member may be attached to front axle 20 that covers first tip member 50 or retaining member 70, which will be described later, and prevents ink on first tip member 50 from drying out.

[0029] Groove 23, pressing surface 27, and locked portion 29 are formed on the inner surface of front axle 20. Groove 23 is a groove that receives outer rib 72 and protrusion 82 (described later) of retaining member 70 when retaining member 70 is attached to front axle 20. Groove 23 is formed to be recessed radially outward from the inner circumferential surface of front axle 20. Each groove 23 extends linearly along axial direction da. Multiple grooves 23 may be arranged at equal angular pitches relative to one another in the circumferential direction. In this embodiment, front axle 20 has four grooves 23. The four grooves 23 are arranged at angular pitches of 90 degrees relative to one another. This is not a limitation, and front axle 20 may have two, three, five or more grooves 23. A barrel-side inclined surface 25 is formed at the rear end of groove 23. Barrel-side inclined surface 25 is a surface that extends inward as it extends rearward. The barrel-side inclined surface 25 has the function of guiding the claw portions 80 (protrusions 82) inward when the holding member 70 is attached to the front barrel 20.

[0030] Pressing surface 27 is a part of the inner circumferential surface of front shaft 20, and has a generally cylindrical shape. Pressing surface 27 has the function of pressing claw portion 80 (protrusion 82) inward after holding member 70 is attached to front shaft 20.

[0031] Locked portion 29 is a portion with which a locking portion 74, described later, of retaining member 70 locks when retaining member 70 is attached to front body 20. Locked portion 29 may be, for example, a convex or concave portion formed on the inner circumferential surface of front body 20. In the present embodiment, locked portion 29 is an annular convex portion formed on the inner circumferential surface of front body 20 and extending in the circumferential direction.

[0032] Ink is contained within the barrel. The ink may be contained directly within the barrel, or may be contained within a barrel with an ink reservoir chamber inside. Alternatively, an ink reservoir may be used. Examples of the ink reservoir include a molded body made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, or nylon, or a metal tubular body. Alternatively, the ink reservoir may be a member with continuous pores (ink reservoir) that can be impregnated with ink and contain the ink. The ink reservoir may be, for example, a heat-sealed fiber bundle, a resin-processed fiber bundle, a resin-processed felt, a needle-punched felt, a porous body such as a sponge, or the like, and may have an outer periphery formed of a synthetic resin film or the like. In this embodiment, an example will be described in which ink occlusion body 11 is disposed inside barrel 15. Ink occlusion body 11 has a substantially cylindrical shape. The central axis of ink occlusion body 11 coincides with the central axis A of writing instrument 10.

[0033] First tip member 50 is a member that forms handwriting on a writing surface such as paper. First tip member 50 is made of a material that allows ink to flow through it in the axial direction da. For example, first tip member 50 may be made of a porous body with continuous pores. Alternatively, first tip member 50 may be made of a fiber bundle, a bristle bundle, felt, or a resin with capillary passages extending in the axial direction da.

[0034] The first tip member 50 has a writing portion 52, an intermediate portion 54, and a rear end portion 56. The writing portion 52 is the portion that forms handwriting on the writing surface. At least a portion of the front of the writing portion 52 protrudes forward from the holding member 70. The writing portion 52 may be, for example, chisel-shaped, since this facilitates the formation of colored areas that encompass characters on the writing surface. However, the writing portion 52 may have other shapes, such as a bullet shape, a rectangular shape, a square prism shape, or a plate shape. The writing portion 52 may be flexible enough to bend and deform in a direction perpendicular to the longitudinal direction in a cross section (the horizontal direction, the left-right direction in FIG. 3 ) due to writing pressure.

[0035] The intermediate portion 54 is located rearward of the writing portion 52 and has a generally cylindrical shape. At least a portion of the intermediate portion 54 contacts an inner rib 71 (described later) of the holding member 70. The rear end portion 56 is located rearward of the intermediate portion 54. The rear end portion 56 has a shape whose cross-sectional area decreases toward the rear. The rear end portion 56 may have, for example, a conical shape, a pyramidal shape, a truncated conical shape, a truncated pyramidal shape, or the like. In this embodiment, the rear end portion 56 has a truncated conical shape whose cross-sectional area decreases toward the rear. The rear end portion 56 is inserted into the ink occlusion body 11 from the front of the ink occlusion body 11. Ink can flow from the ink occlusion body 11 through the rear end portion 56 and the intermediate portion 54 toward the writing portion 52.

[0036] The retaining member 70 is a member that holds the first tip member 50. The retaining member 70 is attached to the front end of the barrel 15. In particular, in the example shown in FIGS. 1 and 2, the retaining member 70 is attached to the front end of the front barrel 20. The retaining member 70 has a generally cylindrical shape. The central axis of the retaining member 70 coincides with the central axis A of the writing instrument 10. The retaining member 70 is formed, for example, by injection molding of a synthetic resin. Examples of synthetic resins that can be used to form the retaining member 70 include polypropylene, polycarbonate, polyethylene, polyacetal, polyethylene terephthalate, elastomer, and acrylonitrile-butadiene-styrene (ABS) resin. The retaining member 70 includes multiple inner ribs (ribs) 71, a support portion 78, and multiple claw portions 80. The retaining member 70 may also include an outer rib 72, a locking portion 74, a flange portion 75, and a ventilation groove 77.

[0037] When the first tip component 50 is inserted into the holding component 70, the inner rib 71 comes into contact with the intermediate portion 54 of the first tip component 50, thereby temporarily fixing the first tip component 50 to the holding component 70. The inner rib 71 is formed to protrude radially inward from the inner circumferential surface of the holding component 70. As shown in FIG. 5 , each inner rib 71 extends linearly along the axial direction da. The multiple inner ribs 71 may be arranged at equal angular intervals in the circumferential direction. In this embodiment, the holding component 70 has four inner ribs 71. The four inner ribs 71 are arranged at 90-degree angular intervals from each other. However, the number of inner ribs 71 is not limited to this, and the holding component 70 may have two, three, five, or more inner ribs 71.

[0038] The diameter of a circle inscribed in the inner ends of the multiple inner ribs 71 is smaller than the diameter of the intermediate portion 54. In this embodiment, the distance between the inner ends of two inner ribs 71 facing each other across the central axis A is smaller than the diameter of the intermediate portion 54. In this embodiment, when attaching the first tip member 50 to the holding member 70, the first tip member 50 is inserted into the holding member 70 from the rear. The writing part 52 passes through the area of ​​the holding member 70 where the inner ribs 71 are formed and protrudes forward. Then, the intermediate portion 54 of the first tip member 50 is pressed into the area of ​​the holding member 70 where the inner ribs 71 are formed. As a result, the outer peripheral surface of the first tip member 50 (intermediate portion 54) is pressed by the inner ribs 71 and deforms inward. At this time, frictional force is generated between the outer peripheral surface of the first tip member 50 (intermediate portion 54) and the inner ribs 71. Therefore, movement of the first tip member 50 in the axial direction da relative to the holding member 70 can be restricted, and the first tip member 50 can be temporarily fixed to the holding member 70.

[0039] The outer ribs 72 are formed to protrude radially outward from the outer peripheral surface of the retaining member 70. As shown in FIG. 4 , each outer rib 72 extends linearly along the axial direction da. When the retaining member 70 is attached to the front axle 20, the outer ribs 72 are positioned within the grooves 23 of the front axle 20. This prevents the retaining member 70 from rotating in the circumferential direction relative to the front axle 20. The multiple outer ribs 72 may be arranged at equal angular pitches from each other in the circumferential direction. In this embodiment, the retaining member 70 has two outer ribs 72. The two outer ribs 72 are arranged at an angular pitch of 180 degrees from each other. However, this is not limiting, and the retaining member 70 may have three or more outer ribs 72.

[0040] The locking portion 74 is a portion that locks onto the locked portion 29 of the front axle 20 when the retaining member 70 is attached to the front axle 20. The locking portion 74 may be, for example, a convex portion or a concave portion formed on the outer peripheral surface of the retaining member 70. In the present embodiment, the locking portion 74 is an annular convex portion that is formed on the outer peripheral surface of the retaining member 70 and extends in the circumferential direction. When the retaining member 70 is attached to the front axle 20, the locking portion 74 climbs over the locked portion 29 and locks onto the locked portion 29. This prevents the retaining member 70 from slipping forward from the front axle 20. Note that the locking portion 74 is not limited to an annular convex portion, and may be, for example, an annular concave portion that is formed on the outer peripheral surface of the retaining member 70 and extends in the circumferential direction. In this case, the convex portion of the locked portion 29 fits into the concave portion of the locking portion 74, thereby locking the locking portion 74 to the locked portion 29. Furthermore, locked portion 29 of front body 20 may be, for example, an annular recess formed on the inner peripheral surface of front body 20 and extending in the circumferential direction. In this case, locking portion 74 is locked to locked portion 29 by fitting a protrusion of locking portion 74 into a recess of locked portion 29. Locking portion 74 is located forward of claw portion 80.

[0041] The flange 75 is formed on the outer peripheral surface of the holding member 70. When the holding member 70 is attached to the front body 20, the flange 75 may come into contact with the front end of the front body 20.

[0042] The ventilation groove 77 is a groove formed across the outer peripheral surface of the holding member 70 and the rear surface of the flange 75. The internal space of the barrel 15 communicates with the outside via the ventilation groove 77. When the ink in the ink occlusion body 11 decreases as a result of writing with the writing instrument 10, air flows into the internal space of the barrel 15 through the ventilation groove 77. Therefore, a decrease in ink causes the pressure in the internal space of the barrel 15 to become negative, preventing the flow of ink from the ink occlusion body 11 to the tip member 50 from stagnating.

[0043] The support portion 78 protrudes forward from the main body of the holding member 70 and extends in a direction substantially parallel to the extension direction of the front portion (writing portion 52) of the first tip member 50. In this embodiment, the holding member 70 has two support portions 78, and the writing portion 52 of the first tip member 50 is disposed between the two support portions 78. The support portion 78 is intended to come into contact with a writing surface, such as a paper surface, when writing with the writing instrument 10. The front end of the support portion 78 is located rearward of the front end of the writing portion 52. In this embodiment, the writing portion 52 is flexible enough to bend and deform in a direction perpendicular to the longitudinal direction of the cross section (lateral direction, left-right direction in FIG. 3 ) due to writing pressure. When writing, the support portion 78 comes into contact with the writing surface, thereby controlling the amount of bending of the writing portion 52 within a predetermined range. This prevents the writing portion 52 from being damaged or broken due to excessive bending. Furthermore, by moving the writing instrument 10 while the two support portions 78 are in contact with the writing surface, the writing portion 52 can bend to a certain degree to form a mark. This makes it possible to mark desired locations on paper placed in an unstable location or on a curved paper surface as intended, and prevents marking locations that do not need to be memorized.

[0044] Here, if the size of the writing portion is larger than the character on the paper, it is easy to mark the character so that it encompasses the character on the paper. However, there are cases where the size of the writing portion is smaller than the character. In this case, it is possible to mark the character so that it encompasses the character by writing along the top edge of the character to form a handwriting (initial handwriting) and then writing along the bottom edge of the initial handwriting in the same way. However, when writing along the bottom edge of the initial handwriting, the handwriting may overlap with the initial handwriting. The overlapping part becomes darker, making it difficult to see the character before the colored transparent sheet is placed. The writing instrument of this embodiment has a support part that allows stable writing, thereby preventing the creation of dark areas of handwriting that overlap with the bottom end of the initial handwriting and allowing handwriting to be formed in close contact with the bottom end of the initial handwriting. Therefore, it is important for the writing instrument to have a support part that comes into contact with the writing surface, such as the surface of paper, when writing.

[0045] In addition, one aspect of the present invention is one in which the support portion 78 is not formed as the main body portion of the holding member 70, but is formed by protruding forward from the front end opening of the barrel 15 (front barrel 20), and extends in a direction approximately parallel to the extension direction of the front portion (writing portion 52) of the first tip member 50 (i.e., an aspect in which the holding member 70 is not provided). Also, an embodiment in which there is only one support portion 78 is also one embodiment of the present invention.

[0046] The multiple claws 80 have the function of restricting movement of the first tip member 50 in the axial direction da relative to the retaining member 70 when the retaining member 70 is attached to the barrel 15 (front axle 20). The claws 80 extend rearward from the main body of the retaining member 70. When the first tip member 50 is disposed within the retaining member 70, the claws 80 are disposed radially outward relative to the first tip member 50. The rear ends of the claws 80 are configured to be deformable so that they can move radially inward. In particular, the claws 80 may be configured to be elastically deformable radially inward.

[0047] The plurality of claw portions 80 may be arranged at equal angular pitches relative to one another in the circumferential direction. In this embodiment, the retaining member 70 has four claw portions 80. The four claw portions 80 are arranged at angular pitches of 90 degrees relative to one another. This is not limitative, and the retaining member 70 may have two, three, five or more claw portions 80. It is particularly preferable that the retaining member 70 have three or more claw portions 80. The retaining member 70 may have the same number of claw portions 80 as the number of groove portions 23 of the front axle 20.

[0048] The claw portions 80 may have protrusions 82, claw-side inclined surfaces 84, and inner inclined surfaces 86. The protrusions 82 are formed to protrude radially outward from the outer peripheral surfaces of the claw portions 80. As shown in FIG. 4 , one claw portion 80 has one protrusion 82. In this case, the retaining member 70 has the same number of protrusions 82 as the number of claw portions 80. In this embodiment, the retaining member 70 has four protrusions 82. The protrusions 82 are formed at the circumferential centers of the corresponding claw portions 80. Therefore, the four protrusions 82 are arranged at an angular pitch of 90 degrees from one another. Note that two or more protrusions 82 may be provided for one claw portion 80. When the retaining member 70 is attached to the front axle 20, the protrusions 82 are guided by the axle-tube-side inclined surfaces 25 of the front axle 20 and are subjected to a pressing force from the front axle 20 that deforms the claw portions 80 radially inward. The claw portion 80 has the protrusion 82, which reduces the radial thickness of the main body of the claw portion 80. Therefore, the claw portion 80 can be easily deformed radially inward.

[0049] A claw-side inclined surface 84 is provided at the rear end of protrusion 82. Claw-side inclined surface 84 is a surface that extends inward as it extends rearward. Claw-side inclined surface 84 has the function of cooperating with barrel-side inclined surface 25 of front body 20 to smoothly deform claw 80 radially inward. Furthermore, even if misalignment occurs between the central axis of retaining member 70 and the central axis of front body 20 when retaining member 70 is inserted into front body 20 from the front-end opening of front body 20, claw-side inclined surface 84 functions as a guide surface, allowing retaining member 70 to be smoothly inserted into front body 20.

[0050] The inner inclined surface 86 is provided on the inner surface of the claw portion 80. When the retaining member 70 is not attached to the barrel 15, the inner inclined surface 86 extends outward toward the rear (see FIG. 6A). When the retaining member 70 is attached to the front axle 20 and the claw portion 80 is deformed inward, the inner inclined surface 86 becomes approximately parallel to the outer peripheral surface of the first tip member 50 (intermediate portion 54). This increases the contact area between the claw portion 80 and the first tip member 50, making it possible to more appropriately restrict movement of the first tip member 50 in the axial direction da relative to the retaining member 70.

[0051] Ink is stored in the writing instrument 50 of this embodiment, and the ink flows inside the first tip member 50 and is ejected from the writing portion to form handwriting. The color of the handwriting formed by the first tip member is a color that is complementary to the color of the colored transparent sheet. Hereinafter, the ink ejected by the first tip member may be referred to as the "first ink," and the color of the handwriting formed by the first tip member is the color of the first ink.

[0052] Generally, "complementary colors" refer to colors that are 180 degrees apart from a specific color on a color wheel, i.e., colors that are directly opposite the specific color. However, in the present invention, "complementary colors" include colors that are 120 to 180 degrees apart from the specific color on a color wheel. Known color wheels include the PCCS (Japan Color Research Institute) color wheel (combined with 24 colors), the Munsell color wheel based on the Munsell color system, and the Oswalt color wheel based on the Oswalt color system. In the present invention, "complementary colors" may be based on any color wheel. Therefore, in the present invention, "complementary colors" include colors that are directly opposite a specific color on a color wheel such as the PCCS, Munsell, or Oswalt color wheel, as well as "analogous colors" with a hue difference of 1 to 3 from the complementary color. Complementary colors on the PCCS color wheel are psychological complementary colors, which refer to the complementary color afterimages that appear when gazing at a chromatic color. Furthermore, complementary colors on the Munsell color wheel and the Oswalt color wheel are physical complementary colors, and physical complementary colors refer to colors that become achromatic when mixed. Therefore, in the present invention, the "complementary colors" in "complementary colors" include both psychological complementary colors and physical complementary colors. In this embodiment, if the colored transparent sheet is red, the color of the writing (the color of the first ink) formed by the first tip member may be green to blue, which is the complementary color of red. Furthermore, if the colored transparent sheet is green, the color of the writing (the color of the first ink) formed by the first tip member may be red to reddish purple, which is the complementary color of green. For example, if a character printed or written in normal black is colored green by writing (marking) it with the first tip member, the black character will be visible in the colored area. If a red colored transparent sheet is placed on the colored area, the colored area will turn black due to the complementary color relationship between green and red, making the character difficult to see, which is effective for memorization.

[0053] A colored transparent sheet (hereinafter sometimes referred to as a "sheet") is a transparent material having a specific color. The colored transparent sheet is a sheet-like material formed by adding a colorant of a specific color to a transparent resin, or a sheet-like material formed from a transparent resin and colored in a specific color. The size of the colored transparent sheet is not particularly limited, and a size (for example, about A6 size) that is easy to use for textbooks, reference books, notebooks, etc. The thickness of the colored transparent sheet is not particularly limited, and may be 50 to 1000 μm.

[0054] Examples of transparent resins include polypropylene and polyethylene terephthalate. If the thickness is about 50 to 100 μm, the sheet is flexible, so it can be properly fitted to a curved surface such as the page of an open textbook. Furthermore, if the transparent resin is a soft resin, the sheet is flexible regardless of the thickness, so it can be easily fitted to a curved surface such as the page of an open textbook. Examples of soft resins include phthalate-free soft vinyl chloride. Transparency refers to the property of transmitting light with wavelengths in the visible light region (the wavelength region of 380 to 780 nm as defined by JIS B 7079). The light transmittance (visible light transmittance) of the colored transparent sheet in the visible light region is preferably 5% or more, more preferably 10% or more, and even more preferably 20% or more. If the visible light transmittance is less than 5%, characters in areas not marked with a writing implement become difficult to see through the colored transparent sheet. The visible light transmittance was measured in the wavelength region of 380 to 780 nm using a spectrophotometer (product name: U-3210, manufactured by Hitachi, Ltd.) with the colored transparent sheet placed on a transparent substrate that transmits light with wavelengths in the visible light region, and the mean value between the maximum and minimum values ​​was used.

[0055] Next, a case will be described in which the color of the writing formed by the first tip member (the color of the first ink) is a color that is complementary to the color of the writing instrument components that make up the writing instrument 50 of this embodiment. In the following description and the drawings used in the following description, parts that can be configured similarly to the above-described embodiment will be designated by the same reference numerals as those used for the corresponding parts in the above-described embodiment, and duplicated description will be omitted.

[0056] Since the color of the first ink is complementary to the color of the writing instrument component, memorization can be performed using the writing instrument component. In other words, the writing instrument component has the same effect as the colored transparent sheet in this specification, allowing memorization to be performed using only the writing instrument without using a colored transparent sheet. Therefore, there is no need to carry a sheet when memorizing, making it easy to carry and store. In addition, there is no need to go through the hassle of selecting a sheet that is complementary to the color of the first ink, and there is no risk of losing the sheet.

[0057] The writing instrument part is transparent and has a specific color. The writing instrument part is a molded product obtained by molding a transparent resin containing a colorant of a specific color, or a molded product made of a transparent resin and colored in a specific color. Examples of transparent resins include polypropylene, polycarbonate, polyethylene, polyacetal, polyethylene terephthalate, elastomers, and acrylonitrile-butadiene-styrene (ABS) resins.

[0058] Examples of writing instrument parts include a barrel, a tail plug or tail cap attached to the rear end opening of the barrel, a cap attached to the tip member side of the barrel, a crown attached to the closed end of the cap, a clip attached to the cap, a support, a holding member, etc. In this embodiment, an example will be described in which the writing instrument part is a holding member having a support portion. Therefore, in this specification, the writing instrument part 70 may be referred to as a "holding member 70." In other words, in this specification, the "writing instrument part 70" and the "holding member 70" can be read interchangeably.

[0059] When the writing implement part is a holding member, the support portion of the holding member can function as a substitute for the colored transparent sheet. For example, if a character printed or written in normal black is colored green by writing (marking) it with the first tip member, the black character will be visible in the colored area. If a red support part is placed over the colored area, the colored area will turn black due to the complementary color relationship between green and red, making the character difficult to see, which is effective for memorization. Therefore, a colored transparent sheet is not required for memorization, and memorization can be performed immediately after writing while holding the writing instrument, allowing for efficient learning.

[0060] In addition, one aspect of the present invention is one in which the support portion 78 is not formed as the main body portion of the holding member 70, but is formed by protruding forward from the front end opening of the barrel 15 (front barrel 20), and extends in a direction approximately parallel to the extension direction of the front portion (writing portion 52) of the first tip member 50 (i.e., an aspect in which the holding member 70 is not provided). Also, an embodiment in which there is only one support portion 78 is also one embodiment of the present invention.

[0061] The writing instrument may further include a component (ink supply component) for supplying ink to the first tip component. The ink supply component is not particularly limited, and examples include an ink guide core made of a fiber bundle or the like, a comb-shaped ink flow rate adjusting component, a porous body with continuous pores that can be impregnated with ink, a pen core consisting of multiple disks arranged in parallel at comb-shaped intervals, each disk having a slit-shaped ink guide groove that runs vertically through the axial direction and a wider vent groove than the ink guide groove, and an ink guide core arranged at the axial center for guiding ink from the ink filling mechanism to the pen tip, and an ink flow rate adjusting component with a valve mechanism. The ink supply component is suitable for cases where ink is stored directly in the barrel or in a barrel with an ink storage chamber inside, and is provided between the front end of the barrel and the first tip component.

[0062] The material for the pen core is not particularly limited as long as it is a synthetic resin that can be injection molded into a structure in which multiple discs are arranged in a comb-like groove pattern. Examples of synthetic resins include general-purpose polycarbonate, polypropylene, polyethylene, and acrylonitrile-butadiene-styrene (ABS) resin. In particular, acrylonitrile-butadiene-styrene (ABS) resin is preferably used because it has high moldability and is easy to obtain pen core performance.

[0063] The valve mechanism can be a conventional, general-purpose pumping type that opens when the tip is pressed, and is preferably set to a spring pressure that can be pressed and released by the pressure of the writing pen.

[0064] The writing instrument may be a retractable writing instrument that houses a refill containing ink in a barrel and has a retraction mechanism that allows the writing part attached to the refill to be retracted from the barrel opening. Any retractable writing instrument can be used as long as the writing part is housed in a barrel exposed to the outside air and the writing part protrudes from the barrel opening when the retractable mechanism is activated.

[0065] Examples of the retraction mechanism include a side-slide type retraction mechanism in which an operating part (clip) that can move in the front-rear direction protrudes radially outward from the rear side wall of the barrel, and the writing tip is retracted from the front end opening of the barrel by sliding the operating part forward; (2) a rear-end knock type retraction mechanism in which the operating part provided at the rear end of the barrel is pressed forward to cause the writing tip to retract from the front end opening of the barrel; a side-knock type retraction mechanism in which the operating part protruding from the outer surface of the barrel side wall is pressed radially inward to cause the writing tip to retract from the front end opening of the barrel; and a rotary type retraction mechanism in which the operating part at the rear of the barrel is rotated to cause the writing tip to retract from the front end opening of the barrel.

[0066] Writing instrument 10 may further include second tip member 12 having a writing portion. Second tip member 12 is a member that forms handwriting on a writing surface such as paper. Second tip member 12 is made of a material that allows ink to flow through it in the axial direction da. Second tip member 12 may be similar to first tip member 50 described above. The color of the writing formed by the second tip member may be a color complementary to the color of the colored transparent sheet or the color of the writing instrument component. That is, the ink ejected from the first tip member and the ink ejected from the second tip member may be the same, and the color of the writing formed by the first tip member and the color of the writing formed by the second tip member may both be a color complementary to the color of the colored transparent sheet or the color of the writing instrument component. Therefore, memorization tasks can be performed using the same colored transparent sheet or the same writing instrument component. In this case, it is preferable that the writing portion of the first tip member and the writing portion of the second tip member have different shapes, allowing them to be used appropriately depending on the application. In the writing instrument of this embodiment, the writing portion of the first tip member is chisel-shaped, and the writing portion of the second tip member is bullet-shaped. This allows the writing portion of the first tip member to form a colored area containing characters on the writing surface, and the first tip member can be used for bold writing. The writing portion of the second tip member is capable of forming thinner handwriting (lines) than handwriting formed by the first tip member, making it easier to form colored areas containing small characters on the writing surface.

[0067] The color of the writing formed by the second tip member may be a color that is the same color as the color of the colored transparent sheet or the color of the writing instrument component, or a composite color formed by subtractive color mixing of the color of the colored transparent sheet or the color of the writing instrument component. In other words, the color of the writing formed by the first tip member and the color of the writing formed by the second tip member are different. Hereinafter, the ink ejected by the second tip member may be referred to as the "second ink," and the color of the writing formed by the second tip member is the color of the second ink. The writing instrument contains the first ink and the second ink. Therefore, writing of different colors can be formed using a single writing instrument, making the writing instrument highly portable and convenient.

[0068] In the present invention, "colors in a similar color relationship" include not only colors identical to the specific color but also "similar colors" with a hue difference of 1 to 3 from the specific color on a color wheel. Known color wheels include, for example, the PCCS (Japan Color Research Institute) color wheel consisting of 24 colors, the Munsell color wheel based on the Munsell color system, and the Oswalt color wheel based on the Oswalt color system. In the present invention, "colors in a similar color relationship" may be based on any color wheel. Therefore, in the present invention, "colors in a similar color relationship" encompasses colors identical to the specific color on a color wheel such as the PCCS color wheel, the Munsell color wheel, or the Oswalt color wheel, as well as "similar colors" with a hue difference of 1 to 3 from the specific color. In this embodiment, if the colored transparent sheet or the writing instrument component is red, the color of the writing (the color of the second ink) formed by the second tip member may be red or a color similar to red, such as reddish purple or orange. Furthermore, in this embodiment, if the colored transparent sheet or writing instrument part has a green color, the color of the writing (color of the second ink) formed by the second tip member may be green, or may be a color similar to green, such as yellow-green or blue-green. For example, when an orange mark (character) is written on the writing surface using the second tip member, the orange character is visible at the writing location. Placing a red colored transparent sheet or writing instrument component on the writing location makes the character at the writing location less visible due to the color relationship between red and orange, which is effective for memorization. Therefore, different types of memorization tasks can be performed using the same colored transparent sheet or writing instrument component by simply changing the writing instrument.

[0069] Furthermore, even if the color of the handwriting formed by the second tip member (the color of the second ink) is not the same color as the color of the colored transparent sheet or the color of the writing instrument component, the memorization task can be performed by using the second ink color as a subtractive color mixture of the colored transparent sheet or the color of the writing instrument component. In this embodiment, if the colored transparent sheet or the writing instrument component is red, the color of the handwriting formed by the second tip member (the color of the second ink) may be orange or pink. In this embodiment, if the colored transparent sheet or the writing instrument component is green, the color of the handwriting formed by the second tip member (the color of the second ink) may be yellow or light blue.

[0070] When a writing instrument contains a first ink and a second ink, it is necessary that the first ink and the second ink do not mix with each other. For example, the first ink and the second ink can be contained in the barrel without being mixed by using a barrel having two ink storage chambers formed by providing a partition wall on the inside, by arranging two ink occlusion bodies in the barrel, each containing the first ink and the second ink, or by providing a partition wall and arranging two ink occlusion bodies in the barrel, one containing the first ink and the other containing the second ink.

[0071] The shape of the writing portion of the second tip member is not particularly limited and may be substantially the same shape as the writing portion of the first tip member. For example, the writing portion of the first tip member and the writing portion of the second tip member may both be chisel-shaped. In this case, it is preferable that the color of the second ink is different from the color of the first ink, allowing writing marks of different colors to be formed using a single writing implement. Since it is easy to distinguish between areas written (marked) with the first tip member and areas written (marked) with the second tip member, it is more preferable that the color of the second ink is a color complementary to the color of the first ink.

[0072] The shape of the writing portion of the second tip member may be different from the shape of the writing portion of the first tip member. In the writing instrument of this embodiment, the writing portion of the first tip member is chisel-shaped, and the writing portion of the second tip member is bullet-shaped. The writing portion of the first tip member can form a colored area containing characters on the writing surface, and the first tip member can be used for bold writing. The writing portion of the second tip member can form a handwriting (line) thinner than the handwriting formed by the first tip member, and the second tip member can be used for fine writing. In this case, it is preferable that the color of the handwriting formed by the first tip member (the color of the first ink) is a color complementary to the color of the colored transparent sheet or the color of the writing instrument component, and the color of the handwriting formed by the second tip member (the color of the second ink) is a color identical to the color of the colored transparent sheet or the color of the writing instrument component, or a composite color formed by subtractive color mixing. For example, if a green colored area is formed by writing (marking) characters printed in normal black using the first tip component, the black characters will be visible in the colored area. If a red colored transparent sheet or a red writing implement component is placed on the colored area, the colored area will turn black due to the complementary color relationship between green and red, making the characters difficult to see, which is effective for memorization. Also, if a pink mark (character) is formed on the writing surface using the second tip component, the pink character will be visible in the written area. If a red colored transparent sheet or a red writing implement component is placed on the written area, the characters will be difficult to see because red is a subtractive color mixture of pink, which is effective for memorization. Therefore, since the shapes of the writing portion of the first tip member and the writing portion of the second tip member are different from each other, and the color of the handwriting formed by the first tip member and the color of the handwriting formed by the second tip member satisfy a predetermined color relationship with the colored transparent sheet or writing instrument parts, different types of memorization tasks can be performed using the same colored transparent sheet or writing instrument parts simply by changing the writing instrument, allowing for efficient learning.

[0073] The location where second tip member 12 is provided is not particularly limited, and for example, first tip member 50 and second tip member 12 may both be provided at one end of barrel 15 (the front end of front barrel 20 or the rear end of rear barrel 40). In this case, it is preferable that the first tip member is provided along central axis A, the second tip member is provided at an angle relative to the first tip member, and the writing tip of the first tip member and the writing tip of the second tip member are arranged with a gap between them. This allows the two writing parts to be used by simply rotating the writing instrument in the circumferential direction without having to change hands. Alternatively, first tip member 50 may be provided at one end of barrel 15 (the front end of front barrel 20), and second tip member 12 may be provided at the other end of barrel 15 (the rear end of rear barrel 40). In writing instrument 10 of this embodiment, the rear end of second tip member 12 protrudes rearward from the rear end of rear barrel 40 and forms a writing portion that forms handwriting. The front end of second tip member 12 is inserted into ink occlusion body 11 from the rear of ink occlusion body 11. A retaining member 70 that holds the second tip member and has two support portions 78 may be attached to the rear end of barrel 15 (rear barrel 40). A rear cap 13 that covers second tip member 12 or retaining member 70 to prevent ink from drying out in second tip member 12 may be attached to rear barrel 40.

[0074] In addition, an embodiment in which the support portion 78 is not formed as the main body portion of the retaining member 70, but is formed protruding rearward from the rear end opening of the barrel 15 (rear barrel 40), and extends in a direction approximately parallel to the extension direction of the rear portion of the second tip member 12 (i.e., an embodiment in which the retaining member 70 is not provided) is also one embodiment of the present invention. Also, an embodiment in which there is only one support portion 78 is also one embodiment of the present invention.

[0075] The writing instrument may further include a component (ink supply component) for supplying ink to the second tip component. The ink supply component is not particularly limited, and examples include an ink guide core made of a fiber bundle or the like, a comb-shaped ink flow rate adjusting component, a porous body with continuous pores that can be impregnated with ink, a pen core consisting of multiple disks arranged in parallel at comb-shaped intervals, with slit-shaped ink guide grooves that run vertically through the disks in the axial direction and wider vent grooves than the ink guide grooves, and an ink guide core arranged at the axial center to guide ink from the ink filling mechanism to the pen tip, and an ink flow rate adjusting component with a valve mechanism. The ink supply component is suitable for cases where ink is stored directly in the barrel or in a barrel with an ink storage chamber inside, and is provided between the rear end of the barrel and the second tip component.

[0076] When the writing instrument 10 is a writing instrument in which the first tip member 50 is provided at one end of the barrel 15 (the front end of the front barrel 20) and the second tip member 12 is provided at the other end of the barrel 15 (the rear end of the rear barrel 40) (i.e., a double-ended writing instrument), it is preferable to provide a retaining member 70 having a support portion at each of the front end of the front barrel 20 and the rear end of the rear barrel 40. In this case, the support portion of the retaining member (first retaining member) that retains the first tip member may be a color that is complementary to the color of the first ink, and the support portion of the retaining member (second retaining member) that retains the second tip member may be a color that is complementary to the color of the second ink. In this embodiment, when the support portion of the first retaining member is red, the color of the first ink may be green or blue, which is a complementary color of red. When the support portion of the second retaining member is green, the color of the second ink may be red or reddish purple, which is a complementary color of green. For example, if a character printed in normal black is marked with a first chip member to form a green colored area, the black character will be visible in the colored area. If a red colored transparent sheet or a red support member is placed on the colored area, the colored area will turn black due to the complementary color relationship between green and red, making the character difficult to read. Similarly, if a red colored area is marked with a second chip member to form a red colored area, the black character will be visible in the colored area. If a green colored transparent sheet or a green support member is placed on the colored area, the colored area will turn black due to the complementary color relationship between red and green, making the character difficult to read. Therefore, memorization tasks can be performed by changing the color of handwriting depending on the purpose (e.g., the importance of the character to be memorized). Furthermore, if the support member has a specific color, in addition to the above effects, a colored transparent sheet is not required, and memorization tasks can be performed immediately after writing while holding the writing instrument, resulting in excellent convenience and efficient learning.

[0077] Next, the process of attaching the tip member and the retaining member to the barrel will be described with reference to Figures 6A to 9D. Figures 6A to 9D are diagrams for explaining an example of the process of attaching tip member 50 and retaining member 70 to barrel 15 (front barrel 20).

[0078] FIG. 6A is a diagram showing the tip member 50, the retaining member 70, and the front axle 20 before the retaining member 70 is attached to the front axle 20, and is a longitudinal cross-sectional view corresponding to line AA in FIG. 3. FIG. 6B is a longitudinal cross-sectional view corresponding to line BB in FIG. 3 at the same time as FIG. 6A. In this embodiment, the inner rib 71 and the claw portion 80 of the retaining member 70 are disposed at a 45-degree angle around the central axis A. In the longitudinal cross-sectional view corresponding to line AA in FIG. 3, the cross section of the claw portion 80 appears, but the cross section of the inner rib 71 does not appear. In addition, in the longitudinal cross-sectional view corresponding to line BB in FIG. 3, the cross section of the inner rib 71 appears, but the cross section of the claw portion 80 does not appear.

[0079] First, the tip member 50 is attached to the holding member 70. In this embodiment, the tip member 50 is inserted into the holding member 70 from the rear. The holding member 70 has an inner inclined surface 86 provided on the inner surface of the claw portion 80. As shown in FIG. 6A , when the holding member 70 is not attached to the barrel tube 15 (front axle 20), the inner inclined surface 86 extends outward toward the rear. In other words, the inner inclined surface 86 extends inward toward the front. Therefore, the tip member 50 that comes into contact with the inner inclined surface 86 and moves forward relative to the holding member 70 is guided by the inner inclined surface 86 and approaches the central axis A. In other words, the inner inclined surface 86 also functions as a guide surface when the tip member 50 is inserted into the holding member 70.

[0080] After the tip member 50 is inserted into the holding member 70, the writing portion 52 of the tip member 50 passes through the region of the holding member 70 where the inner rib 71 is formed and protrudes forward. Then, the middle portion 54 of the tip member 50 is pressed into the region of the holding member 70 where the inner rib 71 is formed. As a result, the outer peripheral surface of the tip member 50 (middle portion 54) is pressed against the inner rib 71 and deformed inward. At this time, a frictional force is generated between the outer peripheral surface of the tip member 50 (middle portion 54) and the inner rib 71. As a result, the tip member 50 is temporarily fixed to the holding member 70. In this state, even if the holding member 70 is held with the writing portion 52 facing upward, for example, the tip member 50 is fixed to the holding member 70 with a force that is strong enough to prevent the tip member 50 from falling out of the holding member 70 due to gravity.

[0081] Fig. 7A is a diagram showing tip member 50, retaining member 70, and front axle 20 when retaining member 70 has been inserted into front axle 20 from the front of front axle 20 and protrusion 82 of retaining member 70 has come into contact with barrel-side inclined surface 25 of front axle 20, and is a longitudinal cross-sectional view corresponding to line AA in Fig. 3. Fig. 7B is an enlarged view of the portion marked 7B in Fig. 7A. Fig. 7C is a longitudinal cross-sectional view corresponding to line BB in Fig. 3 at the same time as Fig. 7A. Fig. 7D is an enlarged view of the portion marked 7D in Fig. 7C.

[0082] Retaining member 70, to which tip member 50 is attached, is inserted into front axle 20 from the front. Retaining member 70 is inserted into front axle 20 so that protrusion 82 of claw portion 80 enters groove 23 of front axle 20. While protrusion 82 is positioned within groove 23, claw portion 80 does not deform in the radial direction. Thereafter, as shown in Figures 7A and 7B, protrusion 82 of claw portion 80 comes into contact with barrel-side inclined surface 25 of groove 23.

[0083] Figure 8A is a diagram showing tip member 50, retaining member 70, and front axle 20 when retaining member 70 has moved further rearward relative to front axle 20 and protruding portion 82 of claw portion 80 is pressed against pressing surface 27 of front axle 20, and is a longitudinal cross-sectional view corresponding to line AA in Figure 3. Figure 8B is an enlarged view of the portion labeled 8B in Figure 8A. Figure 8C is a longitudinal cross-sectional view corresponding to line BB in Figure 3 at the same time as Figure 8A. Figure 8D is an enlarged view of the portion labeled 8D in Figure 8C.

[0084] When the retaining member 70 is moved further rearward relative to the front axle 20, the protrusions 82 of the claws 80 are guided by the barrel-side inclined surfaces 25 of the grooves 23 and move radially inward. At this time, the claws 80 deform radially inward (see FIGS. 8A and 8B). This causes the claws 80 to come into contact with the tip member 50. When the retaining member 70 is moved further rearward relative to the front axle 20, the protrusions 82 are pressed radially inward by the pressing surfaces 27 located rearward of the barrel-side inclined surfaces 25. This causes the claws 80 to grip the tip member 50 with a relatively large force, restricting movement of the tip member 50 in the axial direction da relative to the retaining member 70. Note that at this time, the inner inclined surfaces 86 of the claws 80 become approximately parallel to the outer peripheral surface of the tip member 50 (intermediate portion 54). This increases the contact area between the claws 80 and the tip member 50, and reduces the radial deformation of the tip member 50 even when the claws 80 grip the tip member 50 with a relatively large force. Therefore, the flow of ink inside the tip member 50 is not impeded.

[0085] At this point, the locking portion 74 of the holding member 70 is located forward of the locked portion 29 of the front axle 20, and the locking portion 74 is not locked to the locked portion 29 (see FIGS. 8C and 8D).

[0086] Figure 9A is a diagram showing tip member 50, retaining member 70, and front axle 20 when retaining member 70 has moved further rearward relative to front axle 20 and protruding portion 82 of claw portion 80 is pressed against pressing surface 27 of front axle 20, and is a longitudinal cross-sectional view corresponding to line AA in Figure 3. Figure 9B is an enlarged view of the portion labeled 9B in Figure 9A. Figure 9C is a longitudinal cross-sectional view corresponding to line BB in Figure 3 at the same time as Figure 9A. Figure 9D is an enlarged view of the portion labeled 9D in Figure 9C.

[0087] When retaining member 70 is moved further rearward relative to front axle 20, locking portion 74 of retaining member 70 locks onto locked portion 29 of front axle 20, and retaining member 70 is fixed to front axle 20 (see FIGS. 9C and 9D). In this embodiment, locking portion 74 is an annular convex portion formed on the outer circumferential surface of retaining member 70 and extending in the circumferential direction, and locked portion 29 is an annular convex portion formed on the inner circumferential surface of front axle 20 and extending in the circumferential direction. In this case, the convex portion of locking portion 74 rides over the convex portion of locked portion 29, thereby locking portion 74 to locked portion 29. When the convex portion of locking portion 74 rides over the convex portion of locked portion 29, a relatively large vibration is momentarily generated in retaining member 70. In this embodiment, after the claw portion 80 restricts movement of the tip member 50 in the axial direction da relative to the holding member 70, the locking portion 74 locks with the locked portion 29. Therefore, even if a relatively large vibration occurs in the holding member 70, movement of the tip member 50 relative to the holding member 70 is suppressed.

[0088] The writing instrument 10 of this embodiment comprises a barrel 15, a tip member 50 having a writing portion 52 for forming handwriting, and a holding member 70 that is attached to the barrel 15 and holds the tip member 50. The holding member 70 has a plurality of ribs (inner ribs) 71 that protrude inward and contact the tip member 50, and a plurality of claw portions 80 that extend rearward and are arranged on the outside of the tip member 50. When the holding member 70 is attached to the barrel 15, the claw portions 80 deform inward and contact the tip member 50, thereby restricting movement of the tip member 50 in the axial direction da relative to the holding member 70.

[0089] With this writing instrument 10, the frictional force generated between the outer peripheral surface of the tip component 50 and the rib 71 temporarily fixes the tip component 50 to the holding component 70. Furthermore, the claws 80 deform inward and come into contact with the tip component 50, allowing the claws 80 to grip the tip component 50 with a relatively large force and restrict movement of the tip component 50 in the axial direction da relative to the holding component 70. This prevents the tip component 50 from moving backward relative to the holding component 70, even if a backward force acts on the tip component 50 due to writing pressure when writing with the writing instrument 10. Furthermore, even if a force acts on the tip component 50 in the axial direction da due to an impact such as being dropped on the writing instrument 10, the tip component 50 is prevented from moving in the axial direction da relative to the holding component 70. Therefore, the tip component 50 can be more firmly fixed with a simple configuration.

[0090] In the writing instrument 10 of this embodiment, the rib 71 extends linearly in the axial direction da.

[0091] According to this writing instrument 10, the tip member 50 can be easily inserted into the holding member 70.

[0092] The writing instrument 10 of this embodiment has three or more claw portions 80.

[0093] According to such a writing instrument 10, the tip member 50 can be more firmly fixed by the three or more claw portions 80.

[0094] The writing instrument 10 of this embodiment is provided with a barrel-side inclined surface 25 that is provided on the inner surface of the barrel 15 and extends inward as it moves toward the rear, and / or a claw-side inclined surface 84 that is provided on the outer surface of the claw portion 80 and extends inward as it moves toward the rear.

[0095] According to such writing instrument 10, claw portion-side inclined surface 84 cooperates with barrel-side inclined surface 25 of front barrel 20 to smoothly deform claw portion 80 radially inward. Furthermore, even if misalignment occurs between the central axis of retaining member 70 and the central axis of front barrel 20 when retaining member 70 is inserted into front barrel 20 from the front-end opening of front barrel 20, claw portion-side inclined surface 84 functions as a guide surface, allowing retaining member 70 to be smoothly inserted into front barrel 20.

[0096] The writing instrument 10 of this embodiment includes a protrusion 82 formed on the outer surface of the nail portion 80.

[0097] According to this writing instrument 10, the claw portion 80 has the protrusion 82, which reduces the radial thickness of the main body of the claw portion 80. Therefore, the claw portion 80 can be easily deformed radially inward.

[0098] The writing instrument 10 of this embodiment is provided with an inner inclined surface 86 that is provided on the inner surface of the claw portion 80 and extends outward toward the rear when the holding member 70 is not attached to the barrel 15.

[0099] With this writing instrument 10, when the retaining member 70 is attached to the front barrel 20 and the pawl portion 80 is deformed inward, the inner inclined surface 86 becomes generally parallel to the outer peripheral surface of the tip member 50 (intermediate portion 54). This increases the contact area between the pawl portion 80 and the tip member 50, making it possible to more appropriately restrict movement of the tip member 50 in the axial direction da relative to the retaining member 70.

[0100] Furthermore, when the tip member 50 is inserted into the holding member 70 from the rear, the tip member 50 comes into contact with the inner inclined surface 86 and moves forward relative to the holding member 70, and is guided by the inner inclined surface 86 to approach the central axis A. In other words, the inner inclined surface 86 also functions as a guide surface when the tip member 50 is inserted into the holding member 70.

[0101] The writing instrument 10 of this embodiment has a locking portion 74 provided on the outer surface of the holding member 70 and a locking portion 29 provided on the inner surface of the barrel 15, and when the holding member 70 is attached to the barrel 15, the locking portion 74 locks onto the locking portion 29.

[0102] According to such writing instrument 10, retaining member 70 is fixed to front barrel 20 by locking portion 74 and locked portion 29. Therefore, retaining member 70 and front barrel 20 can be fixed to each other with a relatively simple configuration.

[0103] In the writing instrument 10 of this embodiment, the locking portion 74 is located forward of the claw portion 80 .

[0104] In the writing instrument 10 of this embodiment, when the holding member 70 is attached to the barrel 15 from the front, the claw portion 80 restricts the movement of the tip member 50 in the axial direction da relative to the holding member 70, and then the locking portion 74 locks onto the locked portion 29.

[0105] When the convex portion of locking portion 74 passes over the convex portion of locked portion 29, a relatively large vibration is momentarily generated in holding member 70. According to writing instrument 10 of this embodiment, locking portion 74 locks with locked portion 29 after claw portion 80 restricts movement of tip member 50 in the axial direction da relative to holding member 70, so that even if a relatively large vibration is generated in holding member 70, tip member 50 is prevented from moving relative to holding member 70.

[0106] The ink contained in the ink reservoir may be either a water-based ink or an oil-based ink for writing. The colorant contained in the ink may be a non-discoloring colorant selected from the group consisting of dyes, pigments, and resin particles. Examples of dyes include acid dyes, basic dyes, and direct dyes. Examples of pigments include inorganic pigments, organic pigments, luster pigments, metal powder pigments, fluorescent pigments, and phosphorescent pigments. The pigment may be a microcapsule pigment in which the above-mentioned dye or pigment is encapsulated in a microcapsule. The resin particles may be white resin particles containing no colorant, or colored resin particles containing a dye or pigment. Examples of colored resin particles include colored resin particles in which a dye is homogeneously dissolved or dispersed in resin particles, colored resin particles in which a dye is dyed onto resin particles, colored resin particles in which a pigment is dispersed in resin particles, and colored resin particles in which the surface of resin particles is coated with a pigment. Note that the resin particles also include solid resin particles and hollow resin particles.

[0107] The colorant contained in the ink may be a thermochromic material that changes color depending on temperature. As the thermochromic material, a reversible thermochromic material is preferred because it can repeatedly exhibit color changes due to temperature changes, and is used as a reversible thermochromic colorant. Examples of reversible thermochromic materials include reversible thermochromic compositions containing at least three essential components: (i) an electron-donating color-forming organic compound, (ii) an electron-accepting compound, and (iii) a reaction medium that determines the temperature at which the color-changing reaction between the two occurs. The reversible thermochromic material may be a reversible thermochromic microcapsule pigment in which the reversible thermochromic composition is encapsulated in microcapsules, or reversible thermochromic resin particles in which the reversible thermochromic composition is dispersed in resin particles. Reversible thermochromic materials include thermal decolorization types that are decolorized from a colored state by heating, color memory retention types that alternately retain the colored or decolorized state within a specific temperature range, and thermal color development types that develop color from a decolorized state by heating and return to the decolorized state by cooling from the colored state. Various types can be used alone or in combination.

[0108] The use of a non-color-changing colorant and a reversible thermochromic colorant in combination as colorants can produce an ink that exhibits an entropic color change from a first color to a second color. This is because the reversible thermochromic colorant reversibly changes color from a colored state to a decolorized state in response to a temperature change. The "first color" refers to the color exhibited by the reversible thermochromic colorant when it is in its colored state, and is a mixture of the color of the reversible thermochromic colorant in its colored state and the color of the non-color-changing colorant. The "second color" refers to the color exhibited by the reversible thermochromic colorant when it is in its decolorized state, and is the color exhibited only by the non-color-changing colorant. The entropic color change from the first color to the second color can include a change in color tone (e.g., from a dark color to a light color) or a change in hue (e.g., from purple to pink, or from green to yellow).

[0109] The first ink ejected by the first tip member may be a color-changing ink containing a dye that changes color or fades due to reduction and water. The color-changing ink can be changed or faded by the color-changing liquid described below. Examples of dyes that change color or fade due to reduction include methine dyes, trimethylmethane dyes, diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, cyanine dyes, azo dyes, anthraquinone dyes, etc. Specific examples include CI Basic Blue 1, CI Basic Blue 3, CI Basic Blue 7, CI Basic Blue 54, CI Basic Blue 65, CI Basic Blue 69, CI Basic Orange 21, CI Basic Orange 46, CI Basic Red 13, CI Basic Red 14, CI Basic Red 37, CI Basic Red 49, CI Basic Green 1, CI Basic Green 4, CI Basic Violet 1, CI Basic Violet 10, CI Basic Violet 15, CI Basic Violet 27, CI Basic Yellow 49, CI Acid Blue 93, CI Acid Red 92, CI Acid Green 3, CI Acid Violet 19, CI Acid Yellow 23, etc. By using a dye that changes or fades due to reduction together with a dye or pigment that does not change or fade due to reduction, handwriting is formed in a color that is a mixture of the color of the dye that changes or fades due to reduction and the color of the dye or pigment that does not change or fade due to reduction. By applying a color-changing liquid (described below) to this handwriting, the dye that changes or fades due to reduction changes or fades, resulting in handwriting of a different color.

[0110] To improve the color development of the color-changing ink, the pH of the ink is preferably in the acidic range, more preferably from 3 to 5. When the pH of the ink is adjusted to be in the acidic range of from 1 to 6, an acidic substance is added. Examples of acidic substances include formic acid, acetic acid, propionic acid, lactic acid, oxalic acid, succinic acid, malic acid, citric acid, tartaric acid, malonic acid, phosphoric acid, phosphorous acid, carbonic acid, sulfonic acids such as paratoluenesulfonic acid, hydrochloric acid, sulfuric acid, nitric acid, glycolic acid, and gluconic acid.

[0111] The color-changing ink comprises water. The water is not particularly limited, and examples thereof include tap water, ion-exchanged water, ultrafiltered water, and distilled water.

[0112] The color-changing ink may also contain various other additives as required. Examples of additives include water-soluble organic solvents, shear thinning agents, water-soluble resins, specific gravity adjusters, surfactants, pH adjusters, resin particles, rust inhibitors, wetting agents, viscosity adjusters, preservatives or antifungal agents, bubble absorbers, antifoaming agents, antioxidants, ultraviolet absorbers, lubricants, etc. These additives can be selected from those conventionally used in water-based inks and used as appropriate.

[0113] The second ink ejected by the second tip member is not particularly limited and may be either a color-changing ink or a non-color-changing ink. If the first ink is a color-changing ink and the second ink is a non-color-changing ink, the handwriting formed by the second tip member will not be discolored or erased by the color-changing liquid, so there is no risk of the user accidentally erasing the handwriting formed by the second tip member.

[0114] The color-changing liquid can change or decolorize the color-changing ink containing the dye that changes or decolorizes due to the above-mentioned reducing action. The color-changing liquid contains a reducing agent and water.

[0115] Examples of reducing agents include sodium sulfite, potassium sulfite, lithium sulfite, calcium sulfite, ammonium sulfite, zinc sulfite, sodium thiosulfate, potassium thiosulfate, ammonium thiosulfate, sodium hypochlorite, tin chloride, hydrosulfite, etc. From the viewpoints of safety and the discoloration or decolorization properties of discolorable inks, sodium sulfite is preferred.

[0116] Writing instrument 10 may further include third tip member 60 having an applicator portion. Third tip member 60 is a member that applies a color-changing liquid, discoloring or erasing handwriting made with color-changing ink formed by first tip member 50 or second tip member 12. Third tip member 60 is made of a material that allows the color-changing liquid to flow through it in the axial direction da. Third tip member 60 may be made of a material similar to first tip member 50 and second tip member 12 described above. By providing the writing instrument with a third tip member, it is possible to form handwriting using color-changing ink and erase the handwriting using color-changing liquid using a single writing instrument, making the writing instrument more portable and convenient to use.

[0117] When a writing instrument has a third tip member and contains a color-changing liquid, it is necessary that the color-changing ink and the color-changing liquid do not mix with each other. For example, by using a barrel having two ink storage chambers formed by providing a partition on the inside, by arranging two ink occlusion bodies in the barrel, one containing the color-changing ink and the other containing the color-changing liquid, or by providing a partition and arranging an ink occlusion body in the barrel, one containing the color-changing ink and the other containing the color-changing liquid, the color-changing ink and the color-changing liquid can be contained in the barrel without being mixed.

[0118] The shape of the application portion of the third tip member is not particularly limited and may be substantially the same as the shape of the writing portion of the first tip member. In the writing instrument 10 of this embodiment, the writing portion of the first tip member 12 and the application portion of the third tip member are both chisel-shaped. Because it is easy to discolor or erase the handwriting made with the color-changing ink by the first tip member, it is preferable that the application portion of the third tip member be capable of forming a line with a width thicker than the line width formed by the writing portion of the first tip member. In other words, it is preferable that the application portion of the third tip member is larger than the writing portion of the first tip member. This allows the application portion of the third tip member to abut against the area marked by the writing portion of the first tip member to apply the color-changing liquid to the marked area, so that the color-changing liquid is applied so as to cover the color-changing ink even if it is slightly displaced from the marked area, thereby enabling the color-changing ink to be reliably and easily discolored or erased.

[0119] The shape of the application portion of the third tip member may be different from the shape of the writing portion of the first tip member. Since the third tip member can be used for decorative purposes, it is preferable that the application portion of the third tip member can form lines with a narrower line width than the line width formed by the writing portion of the first tip member. In other words, it is preferable that the application portion of the third tip member is smaller than the writing portion of the first tip member. For example, a configuration in which the first tip member is chisel-shaped and the third tip member is bullet-shaped can be exemplified. The first tip member can form thicker handwriting (lines) than the handwriting formed by the third tip member, and can be used for thick writing. The third tip member can form thinner handwriting (lines) than the handwriting formed by the first tip member, and can be used for fine writing. For example, the first tip member is used to form images such as figures, letters, symbols, and pictures on the writing surface. Then, when figures, letters, or symbols are written on these images using the third tip member, the written areas change color or disappear, making it possible to decorate the image or to form white or colored letters or illustrations on the image. It can also be used for managing tasks (ToDo lists) such as work and schedules. For example, a task is written on the writing surface of a notebook or the like using a regular writing implement (e.g., a mechanical pencil or ballpoint pen), and a figure (e.g., a square or rectangle) is formed on either side (e.g., the left side) of the written task using the first tip member. After completing the task, a symbol (e.g., a check mark) is written inside the figure using the third tip member. The written portion then discolors or fades, forming a white or colorless symbol image inside the figure, making it easy to determine when the task has been completed and facilitating task management.

[0120] The location where the third tip member 60 is provided is not particularly limited, and for example, the first tip member 50 and the third tip member 60 may both be provided at one end of the barrel 15. Alternatively, the first tip member 50 may be provided at one end of the barrel 15, and the third tip member 60 may be provided at the other end of the barrel 15. A retaining member 70 that holds the third tip member 60 and has a support portion 78 may be attached to the rear end of the barrel 15. A rear cap 13 that covers the third tip member 60 or the retaining member 70 and prevents the ink on the third tip member 60 from drying out may be attached to the other end of the barrel.

[0121] In addition, one aspect of the present invention is also one in which the support portion 78 is not formed as the main body portion of the retaining member 70, but is formed protruding rearward from the rear end opening of the barrel 15 (rear barrel 40), and extends in a direction approximately parallel to the extension direction of the rear portion of the third tip member 12 (i.e., an aspect in which the retaining member 70 is not provided). Also, an embodiment in which there is only one support portion 78 is also one embodiment of the present invention.

[0122] In the writing instrument 10 of this embodiment, an ink supply member 17A (first ink supply member) is provided at the front end of the barrel 15, and a first tip member 50 is provided at the front end of the ink supply member 17A via a retaining member 70. An ink supply member 17B (second ink supply member) is provided at the rear end of the barrel 15, and a third tip member 60 is provided at the rear end of the ink supply member 17B via a retaining member 70. Two ink reservoirs (a first ink reservoir 90A and a second ink reservoir 90B) are provided inside the barrel 15, and the ink supply members are fitted into them. The two ink reservoirs are formed by connecting one end of a partition wall 91 to the inner surface of the barrel side wall near the first ink supply member 17A and the other end of the partition wall 91 to the inner surface of the barrel side wall near the second ink supply member 17B. In this embodiment, the ink chamber 90 comprises a central wall 92 extending substantially parallel to the axial direction, and inclined wall 93 and inclined wall 94 extending from both ends of the central wall and inclined with respect to the axis. The inclined wall 93 is integrally connected to the inner surface of the barrel side wall near the first ink supply member 17A, and the inclined wall 94 is integrally connected to the inner surface of the barrel side wall near the second ink supply member 17B. The partition 3 defines a first ink reservoir 95A and a second ink reservoir 95B in a two-layered state, overlapping radially with the partition interposed therebetween. The first ink reservoir 95A is formed in the first ink chamber 90A, and the second ink reservoir 95B is formed in the second ink chamber 90B. In this embodiment, color-changing ink 18A is stored in the first ink reservoir 95A, and color-changing liquid 18B is stored in the second ink reservoir 95B. Ink supply members 17A and 17B are each composed of a number of disks arranged in parallel at comb-like intervals. Each disk has a slit-shaped ink guide groove running axially through it, along with a wider vent hole. An ink guide wick is disposed at the axis and connected to first tip member 50 or third tip member 60. Holding member 70 has two support portions 78, between which is disposed writing portion 52 of first tip member 12 or application portion 62 of third tip member 60, respectively. Support portion 78 is intended to come into contact with a writing surface (application surface), such as paper, during writing or application. The front end of the support portion 78 of the holding member 70 that holds the first tip member 12 is located rearward of the front end of the writing portion 52.The rear end of the support portion 78 of the holding member 70 that holds the third tip member 60 is located forward of the rear end of the applicator portion 62. In this embodiment, the writing portion 52 and the applicator portion 62 are flexible enough to bend in a direction perpendicular to the longitudinal direction in the cross section (lateral direction, left-right direction in FIG. 3 ) due to writing pressure. When writing or applying, the support portion 78 comes into contact with the writing surface or application surface, thereby controlling the amount of bending of the writing portion 52 and the application portion 62 within a predetermined range. This prevents the writing portion 52 and the application portion 62 from being damaged or broken due to excessive bending. Furthermore, by moving the writing instrument 10 while the two support portions 78 are in contact with the writing surface (application surface), application can be performed with the writing portion 52 and the application portion 62 maintaining a constant amount of bending. Therefore, it becomes possible to mark desired locations on paper placed in an unstable location or on a curved paper surface as intended, and further, application of color-changing liquid to locations other than the handwriting formed with the color-changing ink is prevented, making it possible to change color or erase color as intended.

[0123] An embodiment of the present invention also includes writing instrument 10 having first, second, and third tip members. An example of such writing instrument 10 is one in which first and second tip members 50 and 12 are both provided at one end of barrel 15 (e.g., the front end of front barrel 20), and third tip member 60 is provided at the other end of barrel 15 (e.g., the rear end of rear barrel 40).

[0124] The writing instrument of this embodiment may be combined with the above-mentioned colored transparent sheet to form a writing instrument set. That is, the writing instrument set includes the writing instrument and the colored transparent sheet. Here, the color of the handwriting formed by the first tip member (the color of the first ink) is a color that is complementary to the color of the colored transparent sheet. Furthermore, the first ink may be a color-changing ink. By forming the writing instrument set, memorization work can be performed more efficiently. Specific examples of writing instrument sets include (1) a writing instrument set comprising a writing instrument equipped with a first tip member having a chisel-shaped writing portion that forms green writing marks at one end of the barrel, and a red colored transparent sheet; and (2) a writing instrument equipped with a first tip member having a chisel-shaped writing portion that forms red writing marks at one end of the barrel, and a green colored transparent sheet.

[0125] The writing instrument in the writing instrument set includes a first tip member and a second tip member, and the color of the writing formed by the first tip member (the color of the first ink) and the color of the writing formed by the second tip member (the color of the second ink) may both be colors that are complementary to the color of the colored transparent sheet. In other words, the color of the first ink and the color of the second ink may be the same. Furthermore, the first ink and the second ink may be color-changing inks. Specific examples of writing instrument sets include (3) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion that forms red writing at one end of the barrel and a second tip member with a bullet-shaped writing portion that forms red writing at the other end of the barrel, and a green colored transparent sheet; and (4) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion that forms green writing at one end of the barrel and a second tip member with a bullet-shaped writing portion that forms green writing at the other end of the barrel, and a red colored transparent sheet.

[0126] The writing instrument in the writing instrument set includes a first tip member and a second tip member, and the color of the writing formed by the first tip member (the color of the first ink) may be complementary to the color of the colored transparent sheet, and the color of the writing formed by the second tip member (the color of the second ink) may be the same color as the colored transparent sheet or a subtractive color of the colored transparent sheet. In other words, the colors of the first ink and the second ink may be different. The first ink and the second ink may be color-changing inks. Specific examples of writing instrument sets include (5) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion that forms blue writing at one end of the barrel and a second tip member with a bullet-shaped writing portion that forms orange writing at the other end of the barrel, and a red colored transparent sheet; and (6) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion that forms green writing at one end of the barrel and a second tip member with a bullet-shaped writing portion that forms orange writing, and a red colored transparent sheet. Another example is (7) a writing instrument set including a writing instrument having a first tip member with a chisel-shaped writing part that forms red writing at one end of the barrel and a second tip member with a chisel-shaped writing part that forms green writing at the other end of the barrel, and a red colored transparent sheet. However, the above writing instrument set may further include a green colored transparent sheet. That is, it may include both a red colored transparent sheet and a green colored transparent sheet. An embodiment in which the colored transparent sheet is red and green is also one aspect of the present invention.

[0127] The writing instrument in the writing instrument set may include a first tip member and a third tip member, wherein the color-changing ink is ejected from the first tip member and the color-changing liquid is ejected from the third tip member. Specific examples of writing instrument sets include (8) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion at one end of the barrel that forms green writing marks with color-changing ink, and a third tip member with a chisel-shaped application portion at the other end of the barrel that applies color-changing liquid, and a red colored transparent sheet; and (9) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion at one end of the barrel that forms red writing marks with color-changing ink, and a third tip member with a chisel-shaped application portion at the other end of the barrel that applies color-changing liquid, and a green colored transparent sheet.

[0128] The third tip member having an applicator portion for applying the color-changing liquid may be provided in an applicator separate from the writing instrument 10 of this embodiment. That is, handwriting made with color-changing ink formed by the first tip member or the second tip member can be discolored or erased by an applicator equipped with the third tip member. Separate writing instruments and applicators are also preferable because if the ink contained in the writing instrument or the color-changing liquid contained in the applicator runs out during use and the writing instrument or applicator becomes unusable, or if a malfunction occurs in the writing instrument or applicator and the writing instrument or applicator becomes unusable, the user can purchase only the unusable writing instrument or applicator and resume rote learning. In the following description of the applicator and the drawings used in the following description, parts that can be configured in the same way as in the above-mentioned embodiment will be designated by the same symbols as those used for the corresponding parts in the above-mentioned embodiment, and duplicate descriptions will be omitted.

[0129] The form of the applicator is not particularly limited as long as it contains a color-changing liquid in a barrel and has a third tip member that dispenses the color-changing liquid. Examples include various writing implement forms such as a ballpoint pen, a marking pen (marker), a fountain pen, a brush pen, and a calligraphy pen. Marking pen (marker) forms and felt-tip pen forms are preferred as applicators, as they make it easy to apply the color-changing liquid to the colored area formed with the color-changing ink. In addition, the ink contained in the barrel of the writing instrument of this embodiment may be a color-changing liquid. That is, an applicator in which the first tip member and the second tip member are used as a third tip member can be used. The applicator may be a double-ended applicator that includes a third tip member with a chisel-shaped applicator portion at one end of the barrel and a third tip member (third' tip member) with a bullet-shaped applicator portion at the other end of the barrel. A double-ended applicator is also preferable because it makes it easier to discolor or erase a desired area of ​​an area colored with color-changing ink. The applicator may be fitted with a holding member that holds the third tip member and has two support parts, and may also be fitted with a cap that covers the third tip member 12 or the holding member to prevent the discoloring liquid from drying out on the third tip member.

[0130] In addition, one aspect of the present invention is one in which the support portion is not formed as the main body portion of the holding member, but is formed by protruding forward from the opening of the barrel that constitutes the applicator, and extends in a direction approximately parallel to the extension direction of the front portion of the third tip member (i.e., an aspect in which a holding member is not provided). An embodiment in which there is only one support portion is also one embodiment of the present invention.

[0131] The applicator may further include a member for supplying the color-changing liquid to the third tip member (color-changing liquid supply member). The color-changing liquid supply member is not particularly limited, and the same member as the ink supply member described above can be used.

[0132] The applicator may be a retractable applicator that houses a refill containing the color-changing liquid in a barrel and has a retractable mechanism that allows the applicator part attached to the refill to be retracted from the barrel opening. Any retractable applicator can be used as long as the applicator part is housed within a barrel and exposed to the outside air, and the applicator part protrudes from the barrel opening when the retractable mechanism is activated. The retractable mechanism may be the same as the retractable mechanism in the retractable writing instrument described above.

[0133] When a color-changing ink is used in the writing instrument of this embodiment, the writing instrument of this embodiment may be combined with the above-mentioned applicator to form a writing instrument set. That is, the writing instrument set includes the writing instrument and the applicator. Specific examples of writing implement sets include: (1) a writing implement set comprising a writing implement having a first tip member with a chisel-shaped writing portion that forms green writing marks with color-changing ink at one end of the barrel, and an applicator having a third tip member with a chisel-shaped applicator portion that applies color-changing liquid; and (2) a writing implement set comprising a first tip member having a chisel-shaped writing portion that forms red writing marks with color-changing ink at one end of the barrel, and an applicator having a third tip member with a chisel-shaped applicator portion that applies color-changing liquid at the other end of the barrel. a writing instrument set including: (3) a writing instrument having a second tip member with a bullet-shaped writing portion for applying a color-changing liquid to one end of the barrel; and a third tip member having a chisel-shaped applicator portion for applying a color-changing liquid to one end of the barrel, and a third' tip member having a bullet-shaped applicator portion for applying a color-changing liquid to the other end of the barrel; Examples of such a writing instrument set include (4) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion that forms red writing marks with color-changing ink at one end of the barrel and a second tip member with a chisel-shaped writing portion that forms green writing marks with color-changing ink at the other end of the barrel, and an applicator having a third tip member with a chisel-shaped applicator that applies color-changing liquid; and (5) a writing instrument set comprising a writing instrument having a first tip member with a chisel-shaped writing portion that forms green writing marks with color-changing ink at one end of the barrel and a second tip member with a bullet-shaped writing portion that forms orange writing marks with non-color-changing ink at one end of the barrel, and an applicator having a third tip member with a chisel-shaped applicator that applies color-changing liquid.

[0134] The above-mentioned writing instrument set may be further combined with the above-mentioned colored transparent sheet to form a writing instrument set, that is, a writing instrument set comprising a writing instrument, an applicator, and a colored transparent sheet. [Example]

[0135] Examples are shown below. Unless otherwise specified, "parts" in the examples refer to "parts by mass."

[0136] Preparation of color-changing ink A A green color-changing ink was prepared by mixing 1.5 parts of a green dye (CI Basic Green 1), 3 parts of malic acid, 1 part of sodium dihydrogen phosphate, 1 part of a surfactant, 0.3 parts of carbolic acid, 20 parts of diethylene glycol, and 73.2 parts of water.

[0137] Preparation of color-changing ink B A red color-changing ink was prepared by mixing 2 parts of a red dye (CI Basic Red 14), 0.5 parts of a surfactant, 0.1 parts of carbolic acid, 15 parts of glycerin, and 82.4 parts of water.

[0138] Preparation of color changing solution A discoloring liquid was prepared by mixing 10 parts of sodium sulfite, 1 part of potassium carbonate, 0.2 parts of a surfactant, 0.1 parts of carbolic acid, 10 parts of glycerin, and 78.7 parts of water.

[0139] Example 1 Making writing implements A double-ended writing instrument (marking pen) was produced by impregnating an ink occlusion body with discolorable ink A and housing it in a barrel having front and rear openings, connecting a chisel-shaped first tip member to one end of the barrel via a holding member having two supports, connecting a bullet-shaped second tip member to the other end of the barrel, and attaching caps to both ends of the barrel. The writing part of the first tip member was positioned between the two supports, and was flexible enough to bend and deform in a direction perpendicular to the longitudinal direction (lateral direction) in cross section when pressure was applied.

[0140] When black characters printed on a piece of paper (writing surface) were marked with the first tip member of the writing instrument to form a green colored area, the black characters were visible in the colored area. Placing a red colored transparent sheet over the colored area turned the colored area black, making the characters difficult to see, making this a useful writing instrument for memorization tasks. Furthermore, the two support parts allowed for marking of the desired area as intended, and the flexibility of the first tip member allowed for stable marking even on paper placed in an unstable location or on a curved paper surface. Furthermore, the first tip member and the second tip member could be switched appropriately depending on the size of the characters, making this a highly convenient writing instrument. Furthermore, the above writing implements could be combined with a red colored transparent sheet to form a writing implement set. By using this writing implement set, memorization work could be performed more efficiently.

[0141] Example 2 Making writing implements The ink occlusion body was impregnated with color-changing ink A and housed in a bottomed, cylindrical barrel with an opening at its front end. A chisel-shaped first tip member was connected to the ink occlusion body from the opening of the barrel via a holding member with two red supports, and a cap was attached to the opening of the barrel to produce a writing instrument (marking pen). The writing part of the first tip member was positioned between the two supports, and the writing part was flexible enough to bend and deform in the direction perpendicular to the longitudinal direction in the cross section (lateral direction) when pressure was applied.

[0142] Fabrication of applicator The ink occlusion body was impregnated with a color-changing liquid and housed in a barrel with a bottom and a front-end opening, and a chisel-shaped third tip member was connected to the ink occlusion body from the opening of the barrel via a holding member with two support parts, and a cap was attached to the opening of the barrel to produce an applicator in the form of a marking pen. The applicator part of the third tip member was positioned between the two support parts, and the applicator part was flexible enough to bend and deform in the direction perpendicular to the longitudinal direction in the cross section (lateral direction) when pressure was applied to the pen.

[0143] When the first tip member of the writing instrument was used to mark black characters printed on paper (the writing surface), creating a green colored area, the black characters were visible in the colored area. When the red support member was placed over the colored area, the colored area turned black, making the characters difficult to see, making the writing instrument effective for memorization tasks. Because the support member functions as a transparent coloring sheet, memorization tasks could be performed using only the writing instrument without the need for a transparent coloring sheet. This eliminated the hassle of selecting the color of the sheet and the risk of losing the sheet, making the writing instrument highly portable and easy to store. Furthermore, the two support members allowed for marking of the desired area as intended, and the flexibility of the first tip member allowed for stable marking even on paper placed in an unstable location or on a curved surface. When the third tip member of the applicator was used to apply color-changing liquid to a colored area stained with color-changing ink, the color disappeared. The two support parts allowed the color-changing liquid to be applied to the colored area as intended, preventing the color-changing liquid from being applied to areas other than the colored area. Furthermore, the flexibility of the third tip member allowed the color-changing liquid to be applied stably even to paper surfaces placed in an unstable location or that curved. Furthermore, the above-mentioned writing implement and applicator could be combined to form a writing implement set, which allowed for the more efficient erasing or discoloring of memorized portions.

[0144] Example 3 Making writing implements The barrel had two ink-reservoir chambers formed by providing a partition inside the barrel, and a front-end opening and a rear-end opening. Color-changing ink A was stored in one of the ink-reservoir chambers (the first ink-reservoir chamber), a pen core was connected to one end of the barrel as a first ink supply member, and a chisel-shaped first tip member was connected to the front end of the pen core via a holding member having two supports. Furthermore, color-changing ink B was stored in the other ink-reservoir chamber (the second ink-reservoir chamber), a pen core was connected to the other end of the barrel as a second ink supply member, and a chisel-shaped second tip member was connected to the rear end of the pen core via a holding member having two supports. Caps were attached to both ends of the barrel to produce a double-ended writing instrument (marking pen). The writing parts of the first tip member and the second tip member are arranged between two support parts, and the writing parts have flexibility that allows them to bend and deform in a direction perpendicular to the longitudinal direction in the cross section (lateral direction) due to writing pressure.

[0145] When the first tip member of the writing instrument was used to mark black characters printed on paper (the writing surface), creating a green-colored area, the black characters were visible in the colored area. Placing a red-colored transparent sheet over the colored area made the colored area black, making the characters difficult to see, making the writing instrument effective for memorization tasks. Similarly, when the second tip member of the writing instrument was used to mark red, the black characters were visible in the colored area. Placing a green-colored transparent sheet over the colored area made the colored area black, making the characters difficult to see, making the writing instrument effective for memorization tasks. Therefore, memorization tasks could be performed by changing the color of the handwriting depending on the importance of the characters to be memorized. Furthermore, the two support parts allowed for marking of the desired area as intended, and the flexibility of the first and second tip members allowed for stable marking even on paper placed in an unstable location or on a curved paper surface. Furthermore, the above writing implements could be combined with a red colored transparent sheet and a green colored transparent sheet to form a writing implement set. By using this writing implement set, memorization work could be performed more efficiently.

[0146] Example 4 Making writing implements The barrel had two ink-reservoir chambers formed by providing a partition inside the barrel, and a front-end opening and a rear-end opening. One of the ink-reservoir chambers (the first ink-reservoir chamber) contained color-changing ink A, and a pen core was connected to one end of the barrel as a first ink supply member, and a chisel-shaped first tip member was connected to the front end of the pen core via a holding member having two support portions. Furthermore, a color-changing liquid was contained in the other ink-reservoir chamber (the second ink-reservoir chamber), and a chisel-shaped third tip member was connected to the other end of the barrel as a second ink supply member (color-changing liquid supply member) via a holding member having two support portions at the rear end of the pen core. Caps were attached to both ends of the barrel to produce a double-ended writing instrument (marking pen). The writing part of the first tip member and the application part of the third tip member are arranged between two support parts, and the writing part and application part have flexibility that allows them to bend and deform in a direction perpendicular to the longitudinal direction in the cross section (lateral direction) due to writing pressure.

[0147] When the first tip member of the writing instrument was used to mark black characters printed on paper (writing surface), creating a green colored area, the black characters were visible in the colored area. Placing a red colored transparent sheet over the colored area turned the colored area black, making the characters less visible, making the writing instrument effective for memorization. Furthermore, the two support parts allowed for marking of the desired area as intended, and the flexibility of the first tip member allowed for stable marking even on unstable or curved paper surfaces. Next, when a color-changing liquid was applied to the colored area using the color-changing ink with the third tip member of the applicator, the colored area disappeared. The two support parts allowed for the color-changing liquid to be applied to the colored area as intended, preventing the color-changing liquid from being applied to areas other than the colored area. Furthermore, the flexibility of the third tip member allowed for stable application of the color-changing liquid even on unstable or curved paper surfaces. The above-mentioned writing instrument allows the formation of colored areas using color-changing ink and the erasure of colored areas to be performed with a single writing instrument, making it possible to more efficiently perform the memorization task and the erasure or discoloration of memorized areas, and is therefore an excellent writing instrument in terms of portability and convenience. Furthermore, the above writing implements could be combined with a red colored transparent sheet to form a writing implement set, which allowed students to memorize more efficiently.

[0148] Example 5 Making writing implements A first ink reservoir was impregnated with a non-discoloring blue ink and housed in a barrel having front and rear openings. A chisel-shaped first tip member was connected to one end of the barrel via a holding member having two supports. A second ink reservoir was impregnated with a non-discoloring orange ink and housed in the barrel. A bullet-shaped second tip member was connected to the other end of the barrel. Caps were attached to both ends of the barrel to produce a double-ended writing instrument (marking pen). The writing tip of the first tip member was positioned between the two supports, and the writing tip was flexible enough to bend and deform in a direction perpendicular to the longitudinal direction (lateral direction) in the cross section when pressure was applied.

[0149] When the first tip member of the writing instrument was used to mark black characters printed on paper (writing surface) to form a blue colored area, the black characters were visible in the colored area. Placing a red colored transparent sheet over the colored area turned the colored area black, making the characters difficult to see, making the writing instrument effective for memorization. Furthermore, the two support parts allowed for marking of the desired area as intended, and the flexibility of the first tip member allowed for stable marking even on paper placed in an unstable location or on a curved surface. Furthermore, when the second tip member of the writing implement was used to write orange marks (characters) on a piece of paper (writing surface), the characters were visible at the written area. Placing a red transparent sheet over the written area made the characters difficult to see, making the writing implement effective for memorization tasks. Therefore, different types of memorization tasks could be performed using the same transparent sheet by simply changing the writing implement. Furthermore, the above writing implements could be combined with a red colored transparent sheet to form a writing implement set. By using this writing implement set, memorization work could be performed more efficiently.

[0150] Example 6 Making writing implements The first ink reservoir was impregnated with color-changing ink A, and the second ink reservoir was impregnated with orange color-non-changing ink. These were housed in a bottomed, cylindrical barrel with an opening at the front end. A chisel-shaped first tip member was connected to the first ink reservoir through the opening of the barrel via a holding member with two supports. A bullet-shaped second tip member was connected to the opening of the barrel. The first tip member was arranged along the central axis of the barrel, and the second tip member was arranged at an angle relative to the first tip member, with the writing portion of the first tip member and the writing portion of the second tip member spaced apart. The writing portion of the first tip member was arranged between the two supports, and the writing portion was flexible enough to bend and deform in a direction perpendicular to the longitudinal direction (lateral direction) in the cross section due to writing pressure.

[0151] Fabrication of applicator The ink occlusion body was impregnated with a color-changing liquid and housed in a barrel with a bottom and a front-end opening, and a chisel-shaped third tip member was connected to the ink occlusion body from the opening of the barrel via a holding member with two support parts, and a cap was attached to the opening of the barrel to produce an applicator in the form of a marking pen. The applicator part of the third tip member was positioned between the two support parts, and the applicator part was flexible enough to bend and deform in the direction perpendicular to the longitudinal direction in the cross section (lateral direction) when pressure was applied to the pen.

[0152] When the first tip member of the writing instrument was used to mark black characters printed on paper (writing surface), creating a green colored area, the black characters were visible in the colored area. Placing a red colored transparent sheet over the colored area turned the colored area black, making the characters difficult to see, making the instrument effective for memorization. Furthermore, the two support parts allowed marking of the desired area as intended, and the flexibility of the first tip member allowed stable marking even on paper placed in a difficult location or on a curved surface. Furthermore, when orange handwriting (characters) was formed on a piece of paper (writing surface) using the second tip member of the writing instrument, the characters were visible at the written location. Placing a red colored transparent sheet over the written location made the characters at the written location less visible, making this a useful writing instrument for memorization tasks. Therefore, different types of memorization tasks could be performed using the same colored transparent sheet by simply rotating the writing instrument in a circumferential direction without having to change hands. When the third tip member of the applicator was used to apply color-changing liquid to a colored area stained with color-changing ink, the colored area disappeared. The two support parts allowed the color-changing liquid to be applied to the colored area as intended, preventing the color-changing liquid from being applied to areas other than the colored area. Furthermore, the flexibility of the third tip member allowed the color-changing liquid to be applied stably even to paper placed in an unstable location or a curved surface. Furthermore, the handwriting formed by the second tip member did not discolor or fade due to the color-changing ink, preventing the user from accidentally erasing the handwriting formed by the second tip member. Furthermore, a writing set was made by combining the above writing implement, the above applicator, and a red colored transparent sheet. By using this writing set, memorization and the process of erasing or discoloring the memorized parts could be carried out more efficiently. [Explanation of symbols]

[0153] 10 Writing instruments 11 Ink occlusion body 12 second chip member 13 Rear cap 15 Shaft tube 17A First ink supply member 17B Second ink supply member 18A Color-changing ink 18B Discoloration liquid 20 front axle 21 Tsuba 23 Groove 25 Shaft cylinder side inclined surface 27 Pressing surface 29 Locked part 40 rear axle 50 first chip member 52 Writing section 54 Middle section 56 Rear end 60 Third chip member 62 Application section 70 Retaining member 71 Rib (inner rib) 72 outer rib 73 Main body 74 Locking part 75 Tsuba 77 Ventilation groove 78 Support part 79 Thick part 80 Claw 82 Protrusion 84 Claw side inclined surface 85 Gap 86 Inner slope 90A First ink chamber 90B Second ink chamber 91 Bulkhead 92 Central wall 93 Slanted wall section 94 Slanted wall section 95A First ink reservoir 95B Second ink reservoir 100 applicators A Center axis da axial direction

Claims

1. A shaft cylinder and a first tip member having a writing portion for forming handwriting; a support portion extending in a direction substantially parallel to the extension direction of the front portion of the first tip member; A writing instrument comprising: A writing implement, wherein the color of the writing formed by the first tip member is a color that is complementary to the color of the colored transparent sheet.

2. 2. The writing instrument according to claim 1, further comprising a second tip member having a writing portion for forming handwriting, wherein the color of the handwriting formed by said second tip member is selected from the group consisting of a color that is complementary to the color of said colored transparent sheet, a color that is the same color as the color of said colored transparent sheet, and a constituent color obtained by subtractive color mixing of the color of said colored transparent sheet.

3. A shaft cylinder and a first tip member having a writing portion for forming handwriting; a support portion extending in a direction substantially parallel to the extension direction of the front portion of the first tip member; A writing instrument comprising: A writing instrument, wherein the color of the writing formed by the first tip member is a color complementary to the color of a writing instrument component that constitutes the writing instrument, and the writing instrument component is transparent.

4. 4. The writing implement according to claim 3, wherein the writing implement part is the support portion.

5. 5. The writing instrument according to claim 3 or 4, further comprising a second tip member having a writing portion for forming handwriting, wherein the color of the handwriting formed by said second tip member is selected from the group consisting of a color that is complementary to the color of said writing instrument component, a color that is the same color as the color of said writing instrument component, and a constituent color obtained by subtractive color mixing of the color of said writing instrument component.

6. 3. The writing implement according to claim 1, wherein said writing implement contains color-changing ink containing a dye that changes color or loses color through reduction and water, said color-changing ink being ejected by said first tip member.

7. 6. The writing implement according to claim 3, wherein the writing implement contains a color-changing ink containing a dye that changes color or loses color through reduction and water, and the color-changing ink is ejected by the first tip member.

8. 8. The writing implement according to claim 6, further comprising a third tip member having an application portion for applying a color-changing liquid, the color-changing liquid discoloring or erasing handwriting formed with the color-changing ink.

9. 8. The writing implement according to claim 2, wherein the first tip member is provided at one end of the barrel, and the second tip member is provided at one end or the other end of the barrel.

10. The writing implement according to claim 2 , wherein the writing portion of the first tip member and the writing portion of the second tip member have different shapes.

11. 9. The writing implement according to claim 8, wherein the first tip member is provided at one end of the barrel, and the third tip member is provided at one end or the other end of the barrel.

12. The writing implement according to claim 8 or 11, wherein the application portion of the third tip member is larger than the writing portion of the first tip member.

13. A writing instrument according to any one of claims 1, 2, 6, or 8 to 12; A colored transparent sheet, A writing instrument set comprising:

14. A writing instrument according to any one of claims 6, 9, or 10; an applicator containing a color-changing liquid that discolors or erases handwriting formed with the color-changing ink and including a third tip member having an applicator portion that applies the color-changing liquid; A writing instrument set comprising:

15. 15. The writing instrument set according to claim 14, further comprising a colored transparent sheet.

Images