JP2024010349A - ballpoint pen - Google Patents

Abstract

To provide a ballpoint pen that can sufficiently prevent the ball from falling off due to forward movement of ink even when subjected to impact such as dropping or knocking.SOLUTION: Provided is a ballpoint pen, in which a refill includes a writing tip that holds a writing ball at a tip of a holder, a storage tube that stores ink, and a joint that attaches the writing tip to the tip of the storage tube and allows the ink in the storage tube to flow to the writing tip, and the refill is stored in the shaft body. The ballpoint pen has improved impact resistance by including an impact suppression member at the rear end of the joint to suppress movement of ink due to impact, and including an impact suppression member at the rear end side of the joint that grips the ballpoint pen tip to suppress movement of ink due to impact from knocks or drops.SELECTED DRAWING: Figure 1

Description

The present invention relates to a ballpoint pen.

In recent years, in ballpoint pens using shear-thinning inks that contain large particles, ballpoint pen tips with a large flow rate have been required in order to obtain sufficient line density.

In a ballpoint pen tip, one way to ensure a large flow path is to increase the travel distance of the writing ball within the ball house (hereinafter referred to as clearance), but this does not impair the ability of the tip caulking part to hold the ball. To go.

In particular, in the case of shear-thinning ink, when an impact such as a drop or a knock is applied, the ink moves forward toward the chip due to the elasticity of the follower at the rear end of the ink. At this time, since there is wall resistance of the ink storage tube (tube), the amount of ink movement in the center of the storage tube is larger than in the vicinity of the wall surface, and the impact of the moved ink causes great damage to the tip of the ball. Therefore, with a tip having a weak ball holding power, there was a possibility that the writing ball would fall out of the ball house.

In order to prevent the ball from falling out of the ball house, a ballpoint pen has been disclosed in which a coil spring is provided at the rear of the ball to press the ball against the inner wall of the tip end, making it difficult for the writing ball to fall out of the ball house ( (See Patent Document 1). The ink used in this ballpoint pen contains pigments with particle sizes of 0.1 to 80 (μm), and a sealing surface that is approximately the same shape as the ball is provided on the inner wall of the tip of the tip. The clearance in the direction is 30 to 80 (μm), the ink consumption per 100 (m) is 200 to 800 (mg), and the holding force of the ball at the tip of the tip is such that the ballpoint pen refill is moved toward the rear end of the barrel. The pressing force is greater than that of the biasing coil spring to prevent the ball from falling off the tip end of the chip.

Japanese Patent Application Publication No. 2011-240503

However, in the ballpoint pen described in Patent Document 1, although the writing ball does not easily fall off from the ball house, there is a risk of consuming more ink than necessary, and a sufficient writing distance cannot be obtained. In addition, not only does the caulking part contact with the paper surface during writing, causing wear on the caulking part, but also the fibers of the paper rub against each other, and the scraped paper fibers enter the ball house as the writing ball rotates, causing ink to be absorbed. There were problems such as sometimes blocking passages.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a ballpoint pen that can sufficiently prevent the ball from falling off due to forward movement of ink even when subjected to impact such as dropping or knocking. .

The present invention provides a refill with a writing tip that holds a writing ball at the tip of a holder, a storage tube that stores ink, and the writing tip is attached to the tip of the storage tube and allows the ink in the storage tube to flow to the writing tip. The ballpoint pen has a joint and the refill is housed in a shaft body, and the ballpoint pen has an impact suppressing member at a rear end of the joint that suppresses movement of ink due to impact.

The present invention provides a refill with a writing tip that holds a writing ball at the tip of a holder, a storage tube that stores ink, and the writing tip is attached to the tip of the storage tube and allows the ink in the storage tube to flow to the writing tip. a shaft body that accommodates the refill; a coil spring that biases the refill rearward; and a knock that is provided at the rear of the shaft body and rearward of the refill and interlocks with the refill. and a knock-type ballpoint pen that is set to a writing position by pressing the knock part forward and causing the refill to protrude from the tip of the shaft body, wherein the refill has a maximum capacity of ink stored in the refill. is 0.5 ml or more, and the tip of the writing tip is provided with a caulking portion that holds the writing ball, and the force of the caulking portion holding the writing ball is a knock load when pressing the knock portion. or less, and the clearance, which is the amount by which the writing ball can move in the axial direction of the writing tip within the holder, is less than 80 μm, and the average particle diameter of the coloring material contained in the stored ink is 0.1 μm. The ballpoint pen is characterized in that the writing tip is less than the above clearance, and has an impact suppressing member on the rear end side of the joint that grips the writing tip to suppress the movement of ink due to impact when knocked or dropped.

The present invention includes a writing tip that holds a writing ball at the tip of a holder, a storage tube that stores ink, and a joint that attaches the writing tip to the tip of the storage tube and allows the ink in the storage tube to flow to the writing tip. A cap-type refill, a shaft body that accommodates the refill with the tip of the writing tip protruding from the tip of the shaft body, and a cap that removably covers the tip of the shaft body. The ballpoint pen has a maximum capacity of ink stored in the refill of 0.5 ml or more, and has a clearance of less than 80 μm, which is the amount by which the writing ball can move in the axial direction of the writing tip within the holder. The average particle diameter of the coloring material contained in the stored ink is 0.1 μm or more and less than the clearance, and an impact suppressing member for suppressing movement of ink due to impact is provided on the rear end side of the joint that grips the writing tip. This is a ballpoint pen characterized by having:

In the present invention, a caulking portion for holding the writing ball is provided at the tip of the holder of the writing tip, and a caulking portion for holding the writing ball is provided in the internal space of the holder, and a ball is provided at the tip of the holder and into which the writing ball is inserted. A house, a back hole provided from the rear end of the holder to the vicinity of the ball house from the rear end of the holder, and an ink guide hole connecting the back hole and the ball house, and an ink guide hole is formed in the back hole. An elastic member is inserted that urges the writing ball in the distal direction, and the distal end portion of the elastic member extends linearly in the distal direction and passes through the ink guiding hole to the rear end of the writing ball. Preferably, it is formed as a biasing portion that comes into contact with and biases it.

In the present invention, the impact suppressing member is installed at the rear end of the joint so as to face the inside of the housing pipe, and has a hollow portion that communicates the joint and the housing pipe with each other, and the shock suppressing member has a rear end facing the inside of the housing pipe. It is preferable that the shielding structure is such that the radial center is closed and the peripheral part is open, with a meandering passage shape that continues from the opening in the peripheral part to the hollow part in the front interior.

In the present invention, the impact suppressing member is installed at the rear end of the joint so as to face the interior of the housing pipe, and has a hollow portion that communicates the joint and the housing pipe, and the inner diameter of the hollow portion is such that the inner diameter of the impact suppressing member is It is preferable that the amount is in the range of 5 to 30% of the outside diameter of the tube.

According to the present invention, since the movement of ink caused by impact is suppressed by the impact suppressing member at the rear end of the joint, even if an impact such as a drop or knock is applied, the ball is sufficiently prevented from falling off as the ink moves forward. This has the excellent effect of preventing

FIG. 2 is an explanatory diagram of the ballpoint pen according to the first embodiment, in which (a) is a front view, (b) is a side view rotated 90 degrees in the circumferential direction from (a), and (c) is a C- It is a longitudinal cross-sectional view along the C line. FIG. 3 is an explanatory diagram of the refill according to the first embodiment, in which (a) is a front view, (b) is a longitudinal cross-sectional view along line BB in (a), and (c) is an enlarged cross-section around the impact suppressing member. It is a diagram. 3 is a component diagram of the impact suppression member according to the first embodiment, in which (a) is a front perspective view, (b) is a view from the front, (c) is a perspective view from slightly behind, and (d) is a side view. (e) is a longitudinal cross-sectional view taken along line EE in (d), (f) is a cross-sectional view taken along line F-F in (d), (g) is a perspective view from the rear, (h ) is a view from the rear. FIG. 3 is an explanatory diagram of a ballpoint pen according to a second embodiment, in which (a) is a front view, (b) is a side view rotated by 90 degrees in the circumferential direction from (a), and (c) is a C- It is a longitudinal cross-sectional view along the C line. FIG. 6 is an explanatory diagram of a refill according to a second embodiment, in which (a) is a front view, (b) is a longitudinal cross-sectional view along line BB in (a), and (c) is an enlarged cross-section around the impact suppressing member. It is a diagram. FIG. 6 is a component diagram of a shock suppressing member according to a second embodiment, in which (a) is a front perspective view, (b) is a view from the front, (c) is a side view, and (d) is a D of (c). - A vertical cross-sectional view taken along line D, and (f) is a view from the rear.

Hereinafter, a ballpoint pen according to an embodiment will be described with reference to the accompanying drawings.

[First embodiment]
FIG. 1 is an overall explanatory diagram of a knock-type ballpoint pen according to the first embodiment, FIG. 2 is an explanatory diagram of a refill, and FIG. 3 is a component diagram of an impact suppressing member.

As shown in FIG. 1, the knock-type ballpoint pen according to the first embodiment has a refill 10 that contains a writing tip (ballpoint pen tip) 16 that serves as a writing part that holds a writing ball 12 at the tip of a holder 14, and ink. A storage tube (also referred to as an ink storage tube) 18, and a joint 20 that attaches the writing tip 16 to the tip of the storage tube 18 and allows the ink in the storage tube 18 to flow to the writing tip 16. It's about the contained ballpoint pen.

As shown in FIG. 2, the rear end of the joint 20 has an impact suppressing member 24 that suppresses the movement of ink due to impact when knocked or dropped. The joint 20 has a generally tubular shape, the writing tip 16 is inserted into the front part, and a constriction part 20a is provided in the middle of the flow path to narrow down the flow path diameter, and the joint 20 is positioned by abutting the tip end surface of the housing tube 18 on the outer periphery of the rear part. A flange 20b is formed to protrude in the outer radial direction, and an impact suppressing member 24 is fitted into the rear portion to suppress movement of ink due to impact such as knocking or dropping. Note that since the flow path diameter of the constricted portion 20a is also smaller than that of other portions, it has the effect of suppressing ink movement due to impact.

[Impact suppression member 24]
As shown in FIG. 2, the impact suppressing member 24 according to the first embodiment has a structure in which the ink flow path that suppresses the movement of ink due to impact is meandered, and the rear center is closed.

In detail, as shown in FIGS. 2 and 3, the impact suppressing member 24 according to the first embodiment is installed at the rear end of the joint 20 so as to face into the accommodation pipe 18, and the impact suppression member 24 is arranged so that the joint 20 and the accommodation pipe 18 It has a hollow part 24a that communicates with the other parts.
The impact suppressing member 24 has a lid-like shielding structure 24b that closes the radial center at the rear facing into the housing tube 18 and is open at the periphery. A meandering passage (ink flow path, channel) ch (shown by a two-dot chain line in FIGS. 2 and 3) is formed that continues from the opening 24b1 formed in the front inner hollow portion 24a.

As can be understood from the cross-sectional views in FIGS. 3(e) and 3(f), there are four locations in the impact suppressing member 24 extending from the outer periphery of the shielding structure 24b at the rear end toward the front to the hollow portion 24a. is cut into a rectangular cross section to form an opening 24b1. As shown in FIGS. 2 and 3, the meandering path ch leading from the opening 24b1 to the hollow part 24a is oriented toward the inner circumference from the opening 24b1 at a position in front of the shielding structure 24b at the rear end of the impact suppressing member 24, and extends from the opening 24b1 to the hollow part 24a. 24a, and is formed in the shape of a meandering passage approximately in the shape of a crank.

Note that the impact suppressing member 24 has an outer peripheral surface formed in a tapered shape, making it easy to fit into the joint 20.

[Refill 10]
As shown in FIGS. 1 and 2, the refill 10 includes a writing tip 16, which is a writing portion, at the tip. In this case, the writing tip 16 is fitted into the distal end of the joint 20, the joint 20 is fitted into the distal end of the housing tube 18, and the writing tip 16 is provided at the distal end of the housing tube 18 via the joint 20. Note that a follower 18a of liquid or the like is housed in the housing tube 18 behind the ink (not shown) to prevent the housed ink (not shown) from drying out.

As shown in FIG. 1, the ballpoint pen according to the embodiment includes a coil spring 26 for biasing the refill 10 rearward in a shaft body 22 that accommodates the refill 10, and a coil spring 26 provided at the rear of the shaft body 22. 10 and a knocking part 28 that is interlocked with the refill 10, and the knocking part 28 is pressed forward to push the refill 10 through the opening 22a at the tip of the shaft body 22 and the tip of the holder 14 of the writing tip 16. This is a knock-type ballpoint pen that functions as a writing position by protruding. The knock type structure can be a well-known Kern knock type.

A soft elastomer portion 22b is provided to cover the front outer periphery of the shaft body 22, and a protruding clip 22c for fixing in a pocket is provided on the rear outer periphery.

[Writing tip 16]
As shown in FIGS. 1 and 2, the writing tip 16 includes a writing ball 12 and a holder 14 that holds the writing ball 12 at its tip.

As shown in FIG. 2, in the writing tip 16, a caulking portion 14a that holds the writing ball 12 is provided at the tip of the holder 14, and a caulking portion 14a that holds the writing ball 12 is provided in the internal space of the holder 14. A ball house 14b into which the holder 12 is inserted, a back hole 14c provided from the rear end of the holder 14 to the vicinity of the ball house 14b in the distal direction, and an ink guide hole 14d connecting the back hole 14c and the ball house 14b are formed. ing.

Although detailed illustrations are omitted, the ball house 14b has a cylindrical surface that is approximately parallel to the axis, a bottom surface that is a conical surface that continues to the cylindrical surface and decreases in diameter toward the rear, and a curved surface of a writing ball on the bottom surface. It has a transferred ball catch. Ink grooves, which are radial grooves drilled rearward from the ball house 14b side, are formed at a plurality of locations equally distributed around the ink guide hole 14d.

A resilient member 30 that urges the writing ball 12 toward the distal end is inserted into the back hole 14c, and the distal end portion of the resilient member 30 extends linearly toward the distal end and passes through the ink guiding hole 14d. It is formed as a biasing portion that comes into contact with the rear end of the writing ball 12 and biases it.

The maximum capacity of the ink contained in the refill 10 is 0.5 ml or more, and the force of the caulked portion 14a to hold the writing ball 12 is less than or equal to the knocking load when pressing the knocking portion 28.

The clearance, which is the amount by which the writing ball 12 can move in the axial direction of the writing tip 16 within the holder 14, is less than 80 μm, and the average particle diameter of the coloring material contained in the stored ink is 0.1 μm or more and less than the clearance. This is a knock-type ballpoint pen that has a knock mechanism that allows the tip of the refill 10 to be drawn out from the tip (opening 22a at the tip) of the shaft body 22 or pulled into the interior.

The joint 20 that grips the writing tip 16 has an impact suppressing member 24 on the rear end side for the purpose of suppressing movement of ink due to impact when knocked or dropped.
The impact suppressing member 24 has a meandering passage channel (indicated by a two-dot chain line in FIGS. 2 and 3) extending from the opening 24b1 around the lid-shaped shielding structure 24b at the rear end to the hollow portion 24a. It is formed in a generally crank-shaped meandering passage shape, which is connected to the hollow portion 24a and faces toward the inner circumferential direction at a position in front of the shielding structure 24b at the rear end. Therefore, even if the ballpoint pen of the embodiment is subjected to impact such as dropping or knocking, the force of the ink passing through the meandering channel channel is reduced and alleviated, and the ball is sufficiently prevented from falling off due to the forward movement of the ink. Can be done.

That is, there is a mechanism in which when an impact is applied to the refill 10, such as a drop impact, the ink in the storage tube 18 and the follower 18a move rapidly, and the writing ball 12 is pushed out from inside. In the storage tube 18, the amount of movement of the ink and the follower 18a is greatest at the center, while the amount of movement of the ink and the follower 18a is the largest at the center. In response to such a phenomenon, the impact suppressing member 24 absorbs the impact of the ink with a lid-shaped shielding structure 24b, and further prevents the movement of ink in the center from being transmitted to the writing tip 16. This is to reduce the impact, and to obtain the effects thereof, the ink can sufficiently flow to the writing tip 16 side. The same principle can be used to reduce the impact caused by the knock operation.

[Second embodiment]
FIG. 4 is an overall explanatory diagram of a cap-type ballpoint pen according to the second embodiment, FIG. 5 is an explanatory diagram of a refill, and FIG. 6 is a component diagram of an impact suppressing member. Components similar to those of the ballpoint pen of the first embodiment shown in FIGS. 1 and 2 are given the same reference numerals.

Second, the ballpoint pen of the embodiment includes, as shown in FIG. A refill 34 is attached to the housing tube 18 and includes a joint 20 that allows ink in the storage tube 18 to flow to the writing tip 16, and the refill 34 is housed with the tip of the writing tip 16 protruding from the opening 36a at the tip of the shaft body 36. A cap type having a shaft main body 36 (the front shaft 36f is screwed or fitted into the front part of the rear shaft 36r and is integrated), and a cap 38 that removably covers the tip of the shaft main body 36. It is a ballpoint pen.

The maximum capacity of the ink stored in the refill 34 is 0.5 ml or more, and the clearance that allows the writing ball 12 to move in the axial direction of the writing tip within the holder 14 is less than 80 μm, and the ink stored in the refill 34 is The average particle diameter of the coloring material contained in the writing tip is 0.1 μm or more and less than the clearance, and an impact suppressing member 40 is provided on the rear end side of the joint 20 that grips the writing tip 16 to suppress movement of ink due to impact. Note that an open tail plug 18b is fitted into the rear end of the housing tube 18.

As shown in FIG. 5, the impact suppressing member 40 is installed at the rear end of the joint 20 so as to face into the housing tube 18, and has a hollow portion 40a that communicates the joint 20 and the housing tube 18. The inner diameter of the hollow portion 40a is in the range of 5-30% of the outer diameter of the housing tube 18.

Specifically, as shown in FIG. 6, the impact suppressing member 40 has a front end surface tapered toward the hollow portion 40a in a conical shape 40c, and a flange 40b protruding radially outward on the outer periphery of the rear end. Ru. The impact suppressing member 40 is positioned so that the front part fits into the rear part of the joint 20 and the flange 40b abuts the rear end of the joint 20 at the rear end so that it does not fit into the joint 20 too much.
In the impact suppressing member 40, the inner diameter of the hollow portion 40a is in the range of 5 to 30% of the outer diameter of the housing tube 18. Therefore, even if the ballpoint pen of the embodiment is subjected to an impact such as being dropped, the small diameter of the hollow part 40a reduces and alleviates the force of the ink passing through the hollow part 40a, and the ball falls off as the ink moves forward. can be sufficiently prevented.

In the present invention, the optimal configuration of the impact suppressing member added to the rear end of the joint differs depending on the viscosity range of the ink contained in the refill.

Optimal embodiments for each viscosity range are shown below.

[Viscosity range of ink according to first embodiment]
The knock type ballpoint pen according to the first embodiment has a viscosity of 600 mPa·s (25°C) at 1 rpm, 120 mPa·s (25°C) at 10 rpm, and 37 mPa·s (25°C) at 100 rpm. Among aqueous gel inks with a shear thinning index of 0.40, in a relatively low viscosity region, the amount of movement of ink due to impact such as dropping or knocking is relatively large, so the center of the impact suppressing member 24 is blocked. The shape is as shown in Figures 1 to 3. Note that the ink viscosity is preferably 10-200 mPa·s at 100 rpm.

[Viscosity range according to second embodiment]
In the cap type ballpoint pen according to the second embodiment, the viscosity at 1 rpm is 1150 mPa·s (25°C), the viscosity at 10 rpm is 200 mPa·s (25°C), and the viscosity at 100 rpm is 50 mPa·s (25°C). Among water-based gel inks with a shear thinning index of 0.32, in a relatively high viscosity region, the amount of movement of ink due to impact such as dropping or knocking is relatively small, so it is not necessary to block the center of the impact suppressing member 40. Instead, the hollow portion 40a has a shape that narrows the flow path as shown in FIGS. 4 to 6. Note that the ink viscosity is preferably 10-200 mPa·s at 100 rpm.

At this time, it is particularly effective when the inner diameter of the impact suppressing member 40 is within a range of 5 to 30% of the outer diameter of the housing tube 18.

Regarding the ballpoint pen shown in the first embodiment, the diameter A of the writing ball 12 used for the ballpoint pen tip is 0.38 mm, and the ink is black, which is used in a commercially available water-based gel ballpoint pen (UMN-S-38, manufactured by Mitsubishi Pencil). ink is used. As shown in FIGS. 1 to 3, the rear end side of the joint 20 has a shape shown in FIG. The refill 10 equipped with the impact suppressing member 24, which has a shape with four meandering channels each having an opening 24b1 width of 0.5 mm, is inserted into the shaft (shaft main body 22) of the product, and is placed in the concrete. The ball was dropped from the rear end of the shaft from a height of 1 m onto the ground, and the presence or absence of ball flight was confirmed. Table 1 shows the number of falls required for the ball to fly. In each test, the ballpoint pen was dropped from a height of 1 m onto the concrete ground with the rear end of the shaft facing downward, and the presence or absence of ball flight (12 writing balls) was confirmed (number of tests (n = 5)) ). Table 2 shows the average number of falls required for the ball to fly.

As shown in Table 1, it was confirmed that the ball flight resistance effect was significantly improved by having the impact suppressing member. Furthermore, regarding the amount of ink flowing out, even with the impact suppression member, there was no significant decrease in writing using a writing tester compliant with JIS S 6061 (writing speed 4.5 m/min, writing angle 60°, writing force 1N). It wasn't done.

Regarding the ballpoint pen shown in the second embodiment, the diameter A of the writing ball used for the ballpoint pen tip is 0.7 mm, the outer diameter of the ink storage tube is 6 mm, and the ink is a commercially available water-based gel ballpoint pen (URR-100-07, Mitsubishi Using the black ink used for pencils (made with pencils), the shock suppressing member (inner diameter of the hollow part 7 A test was conducted to determine the presence or absence of ball flight with respect to the product of the present invention, in which the refill 34 loaded with the product (type) was inserted into the shaft (shaft body 36) of the product. In each test, the ballpoint pen was dropped from a height of 1 m onto the concrete ground with the rear end of the shaft facing downward, and the presence or absence of ball flight (12 writing balls) was confirmed (number of tests (n = 5)) ). Table 2 shows the average number of falls required for the ball to fly.

As shown in Table 2, it was confirmed that the ball flight resistance effect was significantly improved by having the impact suppressing member whose inner diameter of the hollow part was 5% or more of the outer diameter of the housing tube.

Although the first embodiment and the second embodiment have been illustrated, the present invention is not limited thereto and can be freely modified within the scope of the present invention.

The ballpoint pen of the present invention can be used in various types of ballpoint pens, such as knock-type and cap-type ballpoint pens.

10 Refill 12 Writing ball 14 Holder 16 Writing tip 18 Storage tube 20 Joint 22 Shaft body 24 Impact suppression member (first embodiment)
26 Coil spring 28 Knock part 30 Resilient member 34 Refill 36 Shaft body 38 Cap 40 Impact suppressing member (second embodiment)

Claims (6)

The refill includes a writing tip that holds a writing ball at the tip of the holder, a storage tube that stores ink, and a joint that attaches the writing tip to the tip of the storage tube and allows the ink in the storage tube to flow to the writing tip. , a ballpoint pen in which the refill is housed in a shaft body,
A ballpoint pen characterized in that the joint has an impact suppressing member at a rear end portion thereof that suppresses movement of ink due to an impact. The refill includes a writing tip that holds a writing ball at the tip of the holder, a storage tube that stores ink, and a joint that attaches the writing tip to the tip of the storage tube and allows the ink in the storage tube to flow to the writing tip. ,
A shaft body that accommodates the refill, a coil spring that biases the refill rearward, and a knock portion that is provided at the rear of the shaft body and rearward of the refill and that operates in conjunction with the refill. A knock-type ballpoint pen that is set to a writing position by pressing the knock portion forward to cause the refill to protrude from the tip of the shaft body,
The maximum capacity of the ink contained in the refill is 0.5 ml or more,
The tip of the writing tip is provided with a caulking portion that holds the writing ball, and the force of the caulking portion holding the writing ball is less than or equal to the knocking load when pressing the knocking portion,
The clearance, which is the amount by which the writing ball can move in the axial direction of the writing tip within the holder, is less than 80 μm, and the average particle diameter of the coloring material contained in the ink contained is 0.1 μm or more and less than the clearance. is,
A ballpoint pen characterized in that it has an impact suppressing member on the rear end side of a joint that grips the writing tip to suppress movement of ink due to impact when knocked or dropped. a writing tip that holds a writing ball at the tip of the holder, a storage tube that stores ink, and a refill that includes a joint that attaches the writing tip to the tip of the storage tube and allows the ink in the storage tube to flow to the writing tip;
A cap-type ballpoint pen, comprising: a shaft body that accommodates the refill with the tip of the writing tip protruding from the tip of the shaft body; and a cap that removably covers the tip of the shaft body. ,
The maximum capacity of the ink contained in the refill is 0.5 ml or more,
The clearance, which is the amount by which the writing ball can move in the axial direction of the writing tip within the holder, is less than 80 μm, and the average particle diameter of the coloring material contained in the ink contained is 0.1 μm or more and less than the clearance. is,
A ballpoint pen characterized in that it has an impact suppression member on the rear end side of a joint that grips the writing tip to suppress movement of ink due to impact. A caulking part for holding the writing ball is provided at the tip of the holder of the writing tip, and a ball house provided at the tip of the holder and into which the writing ball is inserted, and a ball house in the internal space of the holder, and a ball house into which the writing ball is inserted. A back hole provided from the rear end to the vicinity of the ball house in the distal direction, and an ink guide hole connecting the back hole and the ball house,
A resilient member that urges the writing ball in the distal direction is inserted into the back hole, and the distal end portion of the resilient member extends linearly in the distal direction and passes through the ink guiding hole. The ballpoint pen according to any one of claims 1 to 3, wherein the ballpoint pen is formed as a biasing portion that contacts and biases the rear end of the writing ball. The impact suppressing member is installed at the rear end of the joint so as to face the inside of the housing pipe, has a hollow portion that communicates the joint and the housing pipe, and has a radial direction at the rear end facing into the housing pipe. 4. The shielding structure according to claim 1, wherein the shielding structure is closed at the center and opened at the periphery, and has a meandering passage shape that continues from the opening at the periphery to the hollow section in the front interior. Ballpoint pen. The impact suppressing member is installed at the rear end of the joint so as to face the inside of the housing tube, and has a hollow portion that communicates the joint and the housing tube, and the inner diameter of the hollow portion is equal to the outer diameter of the housing tube. The ballpoint pen according to any one of claims 1 to 3, characterized in that the amount is in the range of 5 to 30%.

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