JPH1058887A - Ball point pen refill filled with aqueous ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball point pen refill to be applicable to a knock type ball point pen to be carried with its tip in the face-down state and provide the smooth writing feeling and the sharp handwriting in which ink is not leaked out of the tip end and a ball is not feared to drop off when the impact is applied. SOLUTION: A ball point pen refill is formed of the constitution in which aqueous ink 2 provided with shear-thinning properties and an ink follower 3 following the ink 2 are stored in an ink storage cylinder 1 composed of a tip holder component 9 and an ink storage component 10, and a ball point pen tip 4 having a caulking section inner wall face 4f of an end edge 4b gripping the ball 6 formed into the same globular face same as the ball is fitted into an end opening 9a, and also a coil spring 7 pressing the ball 6 at all times is provided on the caulking section inner wall face 4b through a movabl ecomponent 8, and a tail cap 5 with a filtration means is fitted on the rear end. An interstructure section 9g including an ink flowing line controlling the flowing amount of ink 2 and a rear end face 9c is formed on a fitting section 9d with an ink storage component 10 of a tip holder component 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink storage cylinder formed by combining a tip holder member having an ink circulation hole communicating with a front end hole and an ink storage member, or a small diameter portion opening at the front end and an opening at the rear end. An ink container having a large-diameter portion, a water-based ink having a high viscosity in a static state, but having a shear-thinning property in which the viscosity is reduced by rotation of a ball;
The present invention relates to a ball-point pen refill comprising an ink follower which follows the consumption of ink and prevents backflow of ink at the rear part of the ink, and a ball-point pen tip is fitted with a tail plug provided with a ventilation means at the rear end in a tip end hole thereof. For more details,
A coil spring for constantly pressing the ball is provided on the inner wall surface of the tip edge holding the ball of the ballpoint pen tip, directly or via a movable member, from the tip inner hole into the tip hole of the ink storage cylinder. The present invention relates to a ballpoint pen refill intended to prevent ink drying and ink leakage from ink.

[0002]

2. Description of the Related Art A ballpoint pen refill shown in FIG. 7 is disclosed in Japanese Utility Model Laid-Open Publication No. 6-83379. That is, the ink container 1 is composed of a tip holder member 9 in which the ballpoint pen tip 4 is fitted in the tip end hole 9a and a cylindrical ink container member 10, and has a high viscosity in a static state inside, but has a high viscosity. An ink 2 provided with a shear thinning viscosity whose viscosity is reduced by rotation, and an ink follower 3 which follows the consumption of the ink and prevents the backflow of the ink are stored at the rear of the ink. A ball-point pen refill is formed by fitting a tail plug 5 provided with a ball-point pen.

The ballpoint pen refill shown in FIG. 8 is disclosed in Japanese Patent Application Laid-Open No. 7-251591. That is, the ink container 1 has a small diameter portion 1c opening at the front end and a large diameter portion 1d opening at the rear end, and is integrally formed.
A ball-point pen tip 4 is fitted into the tip hole 1a, and a caulked portion inner wall surface 4 of a tip edge 4b holding the ball 6 is provided.
f, a coil spring 7 for constantly pressing the ball is provided directly or via a movable member, and the ink 2 having shear thinning provided therein and the ink follower 3 at the rear of the ink are stored, and the rear end thereof is ventilated. A tail plug 5 provided with means is fitted to form a ballpoint pen.

[0004] Each of the illustrated types of ink storage cylinders is well known as a means for obtaining a large volume ink storage section.
Japanese Patent Laid-Open No. 251591 discloses a configuration of a ballpoint pen refill or a ballpoint pen in which an ink provided with shear thinning is directly packed.
No. 91 discloses a coil spring which presses the ball against the inner wall surface of the tip end edge which holds the ball, which is also a well-known technique, as means for preventing ink drying and ink leakage from the tip end. 1 shows a configuration of a ball-point pen provided directly or via a movable member.

[0005]

Conventionally, ballpoint pens using low-viscosity inks (water-based inks) have been made such that ink is absorbed in an ink occluding body in which cotton-like fibers are covered with a film-like outer cover, and the ink is chipped by a relay core. Like a batting-type water-based ball-point pen that leads to the tip, or a pen-core-type water-based ball-point pen that directly fills the ink container with ink, but uses a pen core member that has a function of adjusting ink discharge by comb grooves, ink grooves, and air grooves. A complicated configuration was required. A ballpoint pen that contains shear-thinned ink that provides sharp handwriting with a smooth writing feel like low-viscosity ink keeps the ink at a high viscosity in a static state, but the ball rotates. Then, a shearing action occurs in the ink in contact with the ball surface, and the viscosity instantaneously decreases to change into a fluid ink. Therefore, there is an advantage that the ink can be easily and directly filled in the ink container.

On the other hand, assuming that an impact force is applied to the refill or the ball-point pen, in the case of the refill or the ball-point pen as shown in FIG. When the ink oscillates due to the shearing action on the surface and the ink's own weight is directed upward, the ink is applied to the ink follower when the tip is directed upward, and when the tip is directed downward, the ball is pressed as an impact force to the ball. Will be. In the case of an ink follower, its viscosity and physical performance such as leakage from the inner surface of the ink storage cylinder can be compensated for, but the one that supports the impact load on the ball is the holding force by caulking the tip edge that holds the ball. When the impact force exceeds the ball holding force, the ball pushes the leading edge and falls off.

[0007] Therefore, as a ballpoint pen that is used by directly filling the ink container provided with the shear-thinning ink into the ink container, the writing portion is covered with a cap having a clip provided so as to be able to be disengaged from clothes, and the tip is directed upward. There is no problem when used as a cap-type ballpoint pen carried in a state where it is carried, and it is used as such, but as a refill, the tip is stored in the shaft cylinder with the tip facing down and the writing part is pressed by a pressing operation on the pressing member. When used in a knock-type ballpoint pen that causes the ball to protrude and retract from the tip opening of the barrel, the ball may fall out of the tip of the tip due to the impact during the intrusion operation or the impact during carrying, causing the ball to fall off And ink will flow out from the tip of the tip and stain the barrel and clothes,
Heretofore, it has not been used as a refill of a knocking ballpoint pen.

An object of the present invention is to maintain good writing performance even when the writing portion is exposed to the outside air, and to obtain a good chip from both the ink composition side and the refill structure side which complements the properties of the ink. Even when the ball is in the downward position, ink leakage (dripping) from the tip of the chip is completely prevented, and furthermore, the ball is prevented from falling off due to the impact force, so that even if the ball falls, the ink is prevented from flowing out from the tip of the chip. In this way, it is an object of the present invention to obtain a ball-point pen refill directly filled with an aqueous ink which can be used for a knock-type ball-point pen with security.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of such a situation, and maintains a good writing performance even when a writing section is exposed to the outside air and keeps a tip in a downward state. As a means for imparting the performance of preventing the ink from leaking (dripping) from the tip of the chip, first, with respect to the ink, 2 to 10% by weight of the dye and 20 to 20% of the moisturizing wetting agent
30% by weight, urea 5-10% by weight, crosslinked acrylic acid polymer 0.2-0.4% by weight, xanthan gum 0.05-
The composition is composed of 0.2% by weight, 1.0% to 5.0% by weight of sorbit, and the balance water. In other words, good writing performance can be obtained by using a dye as a coloring material, the cross-linked acrylic acid polymer and xanthan gum make up for each other's drawbacks, and the synergistic effect of the addition of urea and sorbite makes it possible to write at the time of writing. An ink composition having good writing performance without crying, dents, and blurring, and having a shear-thinning property that has dry-up resistance and does not easily cause ink dripping.

On the other hand, with regard to the means for preventing the ball from falling off due to the impact force acting reversely by imparting the shear thinning property, the ink holding cylinder is combined with the chip holding member and the ink holding member.
In the case of an ink container having a small-diameter portion on which the chip is fitted and a large-diameter portion for storing ink, the ink partition member provided as a separate member in the connecting portion between the small-diameter portion and the large-diameter portion has the respective inks. A lateral groove formed in the axial direction with a radial direction passing through the flow passage to the ink circulation hole, and a longitudinal groove communicating with the lateral groove and the rear end face and restricting a flow amount of ink extending in the axial direction as an ink flow passage. It is formed by: As a result, the impact pressure of the ink that has been shaken by the impact is received at the rear end face of the chip holder member or the ink partition member, and most of the ink pressure from the opening of the vertical groove that regulates the flow rate of the ink. As for the ink load, the impact load is further reduced by the bent ink flow path formed by the vertical groove and the horizontal groove, so that the impact pressure applied to the ball is extremely small.

[0011] Further, as a means in the refill structure surface for maintaining good writing performance even when the writing portion is exposed to the outside air and completely preventing ink leakage (dripping) from the tip of the ball-point pen, In the caulking of the leading edge holding the ball, the inner wall surface of the caulked portion is formed into a spherical surface having the same shape as the ball by rolling caulking in which the caulked portion is pressed against the ball. As a result, the ball-point pen tip holding the ball receives the resilient force of the coil spring on the inner wall surface of the swaged portion of the ball-point tip, so that the valve mechanism at the tip end of the tip where the ball comes into contact makes contact with each other, thereby fulfilling the sealing function. Things.

In addition, as a means for preventing the ink from flowing out from the tip of the tip in the event that the ball falls due to abrasion of the tip edge of the tip or the like, the ink penetrating hole penetrating through the rear hole in the above-mentioned processing of the ballpoint pen tip. Is provided at a predetermined length in the axial direction so that the opening with the rear hole is maintained in a perfect circle, and the ball pressing portion of the movable member has a tip portion directed toward the ink rectification portion. A connecting portion for connecting to a core portion having a diameter larger than the distal end portion is formed on a tapered surface. Thus, when the ball falls, the movable member moves in the tip direction, and a new valve mechanism is brought into contact with the opening of the ink conduction hole of the chip and the connecting portion of the movable member, so that the ink flows from the tip of the chip. Will be blocked.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention in which each of the above means is employed has an ink circulation hole which does not reach a rear end surface in which a tip holder member communicates with a front end hole,
The fitting portion where the ink containing member fits is provided with a radial groove formed in the radial direction communicating with the ink circulation hole, and a longitudinal groove extending in the axial direction as an ink flow passage communicating with the lateral groove and the rear end face. A partition wall including a rear end surface for regulating a flow amount of ink passing through the vertical groove is formed, and dyes 2 to 1 are provided in an ink storage cylinder in which an ink storage member is combined with a fitting portion of the chip holder member.
0% by weight, moisturizing moisturizer 20-30% by weight, urea 5-10
% By weight, 0.2 to 0.4% by weight of a crosslinked acrylic acid polymer, 0.05 to 0.2% by weight of xanthan gum, 1.0 to 5.0% by weight of sorbit, and the balance water. The ink follower is stored in the rear part, and the inner wall surface of the caulking part of the tip edge that holds the ball is formed into a spherical surface of the same shape as the ball, and an ink conduction hole that penetrates the rear hole is provided at a predetermined length in the axial direction. The tip of the tip holder member is fitted with a ball-point pen tip having an opening with the rear hole formed in a perfect circle, and a coil spring that constantly presses the ball against the inner wall surface of the tip is brought into contact with the ball surface. A ball pressing portion having a tapered surface formed with a tip portion and a connection portion connected to a core portion having a larger diameter than the tip portion located behind and near the tip portion, and an ink rectification portion provided with an ink passage on the outer periphery thereof. Consisting of Through the rotary members is disposed, the water-based ink comprising by fitting the tail plug provided with a ventilation means at the rear end of the ink reservoir member is a ball-point pen refill which is packed directly.

Next, in a second embodiment, an ink container made of a metal material having a small-diameter portion opening at the front end and a large-diameter portion opening at the rear end has a connecting portion in which the small-diameter portion and the large-diameter portion continue.
An ink flow passage that penetrates in the axial direction through the ink flow passage that penetrates in the axial direction and that does not reach the rear end surface; An ink partition member formed by a lateral groove formed in the radial direction communicating with the hole toward the axis, and a longitudinal groove extending in the axial direction by regulating the flow rate of the ink communicating with the lateral groove and the rear end face. 2 to 10% by weight of a dye, 20 to 30% by weight of a moisturizing humectant, 5 to 10% by weight of urea, 0.2 to 0.4% by weight of a cross-linked acrylic acid polymer, and 0.1% of xanthan gum in the ink container. 0.5-0.2% by weight, sorbit
An ink consisting of 0 to 5.0% by weight and the balance of water and an ink follower are stored at the rear of the ink, and a caulking portion inner wall surface at the leading edge for holding the ball is formed into a spherical surface having the same shape as the ball. An ink passage hole penetrating through the hole is provided at a predetermined length in the axial direction, and the opening with the rear hole is formed in a perfect circle. A ballpoint pen tip is fitted into the tip hole of the ink containing cylinder, and the tip is swaged. A ball spring having a tapered surface formed by a coil spring that constantly presses the ball against the inner wall surface, and a connecting portion that connects a tip portion that contacts the ball surface and a core portion that is larger in diameter than the tip portion located behind and near the tip portion. A water-based ink, which is disposed via a movable member including a pressing portion and an ink straightening portion provided on an outer periphery of an ink passage, and a tail plug provided with a ventilation means is fitted to a rear end of the ink storage cylinder. Ball stuffed directly A refill.

The ballpoint pen refill constructed as described above is housed in the barrel with the tip facing downward and the writing section exposed to the outside air, and the writing section is moved to the tip of the barrel by a pressing operation on the pressing member. The knock-type ballpoint pen that appears and disappears from the opening can be used with confidence. In other words, the ink has excellent writing performance in terms of the composition of the ink, has good writing performance without crying, rubbing, and blurring during writing, and hardly leaks (hangs) from the tip of the tip even when the tip is placed in a downward position. In addition to improving the ink, on the refill structure side, if a shock is applied due to the nature of the ink, the whole ink will swing and the ball will not act as an impact load on the ball. In addition, in order to completely prevent ink leakage from the tip of the tip, the inner wall surface of the tip of the tip that holds the ball is formed into a spherical surface of the same shape as the ball, so that the pressed ball comes into close contact. In the event that the ball falls off, the opening of the ink conduction hole of the chip and the bob of the movable member which is repelled by the coil spring and presses the ball Each improvement to prevent ink flow out from the tip end by the new valve mechanism by the pressing portion is achieved, it is obtained by completing the refill which can be used for knock-type ballpoint pen with confidence as above follow.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings showing embodiments. Note that the same reference numerals as those used in the description of the above-described prior art examples denote the same members and parts, and the description will be made using the same reference numerals.

FIG. 1 is a longitudinal sectional view showing a ball-point pen refill which can be mounted on a knock-type ball-point pen according to a first embodiment of the present invention and is directly filled with an aqueous ink having a shear thinning property. The ball-point pen refill according to the present invention has a high viscosity in a static state, but has a low viscosity due to the rotation of the ball, in the ink storage cylinder 1 in which a chip holder member 9 made of a plastic material and an ink storage member 10 are combined. And a paste-like ink follower 3 which follows the consumption of the ink and prevents the backflow of the ink at the rear of the ink, and the tip hole 9a of the tip holder member is formed from a stainless steel wire rod. A coil spring 7 that fits the chip 4 and constantly presses the ball on the inner wall surface 4f that holds the ball 6 is provided via a movable member 8 , and ventilation means is provided at the rear end of the ink containing member. It is configured by fitting a tail plug 5.

FIG. 2 is a longitudinal sectional view showing a ball-point pen refill directly filled with a water-based ink having a shear-thinning property which can be mounted on a knock-type ball-point pen in the same manner as the first embodiment in the second embodiment of the present invention. is there. Ballpoint refill of the present invention, the ink reservoir tube 1 formed by molding a stainless material having a large diameter portion 1d that is open at the small diameter portion 1c and a rear end which is open at the tip, the ink partition wall member 11 and the small-diameter portion larger A ball-point pen tip is disposed in the connecting portion 1b of the diameter portion, and further contains an aqueous ink 2 provided with shear thinning and an ink follower 3 at the rear portion of the ink, and a tip end hole 1a of the small diameter portion is formed from a stainless steel wire. 4 as well as fitted, and the coil spring 7 that always presses the ball into the caulking portion wall 4f for holding the ball 6 is disposed through the movable member 8, provided with ventilation means to the rear end of the large diameter portion tail It is configured by fitting a stopper 5.

Next, the composition and characteristics of the water-based ink provided with shear thinning viscosity used in the examples of the present invention will be described in detail.

The composition of the ink is as follows: Direct Black 154 7.5% by weight Ethylene glycol 20.0% by weight Urea 10.0% by weight Sorbit 1.0% by weight Rust preventive lubricant (phosphate ester surfactant) 0.5 % By weight pH adjuster (triethanolamine) 0.5% by weight Antibacterial agent (XL-2) 1.0% by weight Crosslinked acrylic acid polymer 0.25% by weight Xanthan gum 0.15% by weight Ion-exchanged water Remaining ions Mix exchange water and ethylene glycol, then add urea, sorbite, dye, rust preventive lubricant, pH adjuster, and antibacterial agent, mix with stirring, and then add and mix cross-linked acrylic acid polymer and xanthan gum. Ink was used.

The ink having the above-mentioned composition shows good results without crying, scumming and blurring in writing performance, and has a dry-up resistance of 3 months in a horizontal state in an environment of 50 ° C. and 30% RH. Thereafter, when the temperature is returned to room temperature and a straight line is written, the line has a performance of good writing without causing line skipping and blurring within 3 cm.
After leaving for 3 months in a horizontal position in an environment of 0 ° C. and 0% RH,
The ink shows good performance with no precipitate in the ink and a viscosity increase rate of 30% or less.

The first feature of the ink used in the present invention resides in that a dye is used as a coloring material instead of a pigment. When a dye is used as a coloring agent, there is an advantage that even if the water in the ink evaporates and the ink at the tip of the chip is solidified, the ink is re-dissolved when the ink is supplied and writing can be performed without problems. The use ratio of the dye is 2 to 10% by weight. If it is less than 2% by weight, the handwriting is light, and if it is more than 10% by weight, solidification at the time of dry-up is severe and writing performance deteriorates.

A second feature of the ink used in the present invention resides in that a crosslinked acrylic acid polymer and xanthan gum are used in combination to impart shear thinning to the ink. The crosslinked acrylic acid polymer does not remarkably thicken or form a film even when the water in the ink evaporates. However, there is a problem that it is difficult to lower the viscosity to a desired viscosity at the time of writing and to maintain a high viscosity at rest at the time of writing because the degree of sway is small, and the shear thinning action is not sufficient. Further, since xanthan gum has a large degree of swaying and a large shear thinning property, the ink does not hang down from the ballpoint pen when used in a ballpoint pen, and it is easy to adjust the viscosity to a good handwriting when writing. There is a problem that writing becomes impossible due to remarkable thickening due to water evaporation and film formation at the tip of the chip. The ink used in the present invention uses a cross-linked acrylic acid polymer as a main shear-thinning agent in order to prevent deterioration of writing performance due to moisture evaporation, and is insufficient for preventing ink dripping and maintaining high viscosity at rest. Is supplemented with the addition of xanthan gum,
These synergistic effects achieve good writing performance with no crying, no dents, no blemishes, etc. In addition, there is no significant thickening or film formation even when the water in the ink evaporates, and the dry-up resistance is also good. What was done. The use ratio of the crosslinked acrylic acid polymer is 0.2 to 0.4% by weight.
At 0.2% by weight or less, the desired ink viscosity is not obtained and the writing performance is impaired, and the dry-up resistance is poor. At 0.4% by weight or more, the viscosity is sufficiently reduced due to the shearing force of the ball during writing. The writing performance is not good. Further, the usage ratio of xanthan gum is 0.05 to 0.2% by weight.
If the content is less than 0.05% by weight, the desired viscosity cannot be obtained and the performance is lowered. If the content is more than 0.2% by weight, not only does the film formation at the tip of the chip become strong and the writing becomes poor, but also inside the chip during dry-up. Precipitates are generated and the ink becomes unstable.

A third feature of the ink used in the present invention is that urea is added. Urea has a function of dissolving the dye together with the action of suppressing the evaporation of water, and has a great function as a dissolution aid against re-dissolution when the water in the ink evaporates and the dye solidifies. In this case, the combination with urea greatly contributes to improvement of dry-up resistance and re-dissolution. The use ratio of urea is 5
-10% by weight. If it is less than 5% by weight, the moisturizing performance and the dye dissolving ability are reduced, and the dry-up resistance is not good.
If it is more than 10% by weight, the difference in viscosity between when a shearing force is applied and when it is not applied becomes small, and good writing performance cannot be obtained.
In addition, urea crystals precipitate during water evaporation, which hinders the flow of ink.

A fourth feature of the ink used in the present invention is that sorbite is added. Sorbit is rich in hygroscopicity, has a large function in retaining moisture in ink, and has a relatively small increase in the viscosity of sorbit due to dry-up, so that it greatly contributes to maintaining ballpoint pen performance over time. The use ratio of sorbit is 1.0 to 5.0% by weight. When the content is 1.0% by weight or less, the moisture retention is insufficient and the dry-up resistance is poor. When the content is 5.0% by weight or more, the ink thickening rate at the time of dry-up is increased and the dry-up resistance is reduced.

The moisturizing moisturizer is one or two selected from dihydric alcohols, trihydric alcohols and derivatives of these alcohols.
That is all. Specifically, it is one or more selected from ethylene glycol, polyethylene glycol, and glycerin. The usage ratio of the moisturizing moisturizing agent is 20 to 30% by weight. If it is less than 20%, the dry-up resistance is low and the ink solidifies at the tip of the chip. If it is 30% or more, the dry-up resistance is good, but bleeding, crying, and dents occur in the handwriting.

In addition, 0.2 to 2.0% by weight of a rust preventive lubricant, 0.5 to 2.0% by weight of a pH adjuster, and 1.
0-2.0% by weight can be added. The rust inhibitor is at least one selected from a phosphate ester surfactant, benzotriazole, and a fatty acid ester. The pH adjuster is triethanolamine, and the antibacterial agent is 1,2-benzisothiazolin-3-one (XL-2: Zeneca Corporation)
Manufactured).

The ink used in the present invention having the above composition is intended to be used for a ballpoint pen refill mounted on a knock-type ballpoint pen which is carried with the tip end facing down and exposed to the outside air. .
Therefore, since the ink is provided with shear thinning, it maintains a high viscosity in a static state, but when a shearing force is applied by the rotation of the ball during writing, the viscosity is instantaneously reduced and the ink becomes fluid. The advantage is that clear handwriting can be obtained with a smooth writing feel. However, on the other hand, when an impact is applied to the refill, a shear force acts on the contact surface between the ink container and the ink, and the entire ink swings, and the ink weight becomes an impact force.
Because it has the property of directly hitting the ball and ink follower,
A means corresponding to this property is required in the structure of the refill.

The ink reservoir tube 1 of the ballpoint pen of a first embodiment of the present invention refill (see FIG. 1) is fitted the ink reservoir member 10 to the fitting portion 9d cylindrical tip holder member 9 made of plastic material The chip holder member is configured as follows in order to supplement the properties of the ink 2 used in the present invention having the above-mentioned shear thinning property. As shown in the enlarged view of FIG. 3, the tip holder 9 has a tip hole 9a into which the ball-point pen tip 4 made of stainless steel wire is fitted.
And an abutting flange 9h which is in contact with the front end surface of the ink storage member 10 on the outer periphery and an ink storage member is provided at the rear of the abutting flange. A lateral groove 9e formed in the fitting portion 9d, which is formed in the radial direction and communicates with the ink circulation hole, and a longitudinally extending axial direction which serves as an ink flow passage communicating with the lateral groove and the rear end face. Groove 9
f, and a partition wall 9g including a rear end surface 9c for regulating the flow of ink is formed. The cross-sectional area of the vertical groove that opens at the rear end surface that regulates the flow amount of ink should be at least 0.2
mm ² is sufficient, and it is important not to make it larger than necessary.

[0030] ink reservoir tube 1 a stainless steel material made by molding of ballpoint refill in the second embodiment of the present invention (see FIG. 2), the small diameter portion 1c and the large diameter ink partition wall member 11 made of plastic material The partition part 9 of the chip holder member 9 of the first embodiment is disposed in the connecting part 1b of the part 1d.
Like g, it is a means for supplementing the properties of the ink 2 used in the present invention. That is, the ink partition member 11, as shown in the enlarged view of FIG. 4, a small diameter portion 1c of the ink accommodating tube 1
And a rear end portion 11b located in the large diameter portion 1d. The front end portion 11a has a front end surface as a spring receiving portion 11c for supporting the rear end of the coil spring 7,
An ink circulation hole 11e opened at the front end surface and not penetrating to the rear end surface 11d communicates with the rear end portion 11b, and a lateral groove 11f formed in the rear end portion in a radial direction communicating with the ink circulation hole.
And a vertical groove 11g communicating with the horizontal groove and opening the rear end face thereof to regulate the flow of ink. The same applies to the tip holder member 9 of the first embodiment, in which a plurality of horizontal and vertical grooves of the ink flow path are provided at symmetrical positions in the radial direction, but one of the ink flow paths is clogged. The point that the performance is not affected even if a defect such as occurs.In addition, on the part processing side where resin material is injection molded,
There are advantages such as stabilizing the cantilever core pin of the ink circulation hole by sandwiching it from both upper and lower sides. Also, the ink barrier rib member 11 which is disposed in the ink reservoir tube 1, the deformable portion 1e which is plastically deformed from the outside to the point or linear towards the axis of the ink accommodating tube in its installed position, integral to the ink accommodating tube It is preferable that they are fixed securely. As a fixing means, there is a separate method such as press-fitting, but it is important to integrally fix so as not to be positioned over time.

When an impact force is applied to the refill in the state where the tip end is downward by the means of the first and second embodiments, most of the impact load caused by the ink oscillated in the ink storage cylinder 1 is reduced to the first embodiment. In the case of the example, a chip holder member
A rear end surface 9c of 9 In the case of the second embodiment will be received in the rear end surface 11d of the ink partition wall member 11, longitudinal grooves 9f which respectively open at the rear end face, the ink load even lateral groove 9e through 11g, at 11f Since the ball is received, the impact load of the ink applied to the ball 6 is limited to a very small amount of ink load from the ink circulation holes 9b and 11e to the ball, and cannot be an impact force for pushing the ball outward, and therefore is applied to the refill. This prevents the ball from falling off due to the impact force.

The ballpoint pen tip 4 obtained by processing a stainless steel wire rod used in the present invention can be obtained by substantially the same processing means as a normal ballpoint pen tip. However, as shown in FIG. The ball 6 inserted therein is supported by a ball seat 4c in which a plurality of ink grooves 4g are formed in the bottom of the ball house, and the other end edge 4
Then, the caulking jig T is pressed against the ball to be pressed against the ball, and the inner wall surface 4f of the caulked portion is formed into a spherical surface having the same shape as the ball. Thereafter, the upper surface of the ball exposed from the leading edge is hammered with a hammer rod H. Then, the ball seat is plastically deformed in the rear end direction by a predetermined amount to secure a clearance Q with the ball in the ball house.

Further, in the ball-point pen tip 4 , the length of the ink passage hole 4e communicating with the ball house 4a and the rear hole 4d is set to be slightly longer than that of a normal ball-point tip, and the ink to be engraved on the ball seat 4c is formed. When processing the groove 4g or rolling and caulking the leading edge 4b, the upper surface of the ball is hammered to plastically deform the ball seat portion. It is manufactured such that the length is set and the opening 4h opened by the rear hole is formed in a perfect circle.

According to the present invention, the ball-point pen tip 4 formed as described above is fitted in the tip hole 9a of the tip holder member 9 in the first embodiment, and in the tip hole 1a of the ink container 1 in the second embodiment. With the leading edge 4 holding the ball 6
In the first embodiment, a coil spring 7 for constantly pressing the ball against the inner wall surface 4f of the caulking portion 4b is provided at the tip end hole of the tip holder member via the movable member 8 , and in the second embodiment, the spring receiving portion 11c of the ink partition member 11 is provided. The rear end is supported and arranged.

As shown in FIGS. 3 and 4, the movable member 8 interposed between the ball 6 and the coil spring 7 has an ink passage hole 4 of the tip 4 whose tip surface contacts the ball surface.
ball pressing portion 8a including a tip portion 8c having a diameter smaller than the diameter of e
The ink passage 8f is provided on the outer periphery thereof, and a rear end face 8e is formed by an ink rectifying portion 8b which is in contact with the coil spring 7. Further, the tip 8c of the ball pressing portion 8a has an ink rectifying portion 8c.
The connecting portion 8h connecting to the core portion 8d having a larger diameter than the tip portion toward the tip b is a tapered surface. The circumference of the ink is divided at equal intervals by the rib-shaped blades 8g.
f is formed. In the embodiment, the ink passage is defined by the rib-shaped blade portion. However, the present invention is not limited to this, and the point is that the ink passing through the position where the coil spring is disposed can smoothly flow without causing turbulent flow. It should be taken into consideration that it flows into the department.

According to the present invention, when the refill is carried or left with the chip facing downward, ink leakage from the tip of the chip (when the refill is carried by the ball pen tip 4 and the movable member 8 pressed by the coil spring 7). In addition to preventing dripping, the ink can be prevented from flowing out from the tip when the ball falls outside due to abrasion of the edge of the tip by writing or the like.

That is, the ball 6 of the ball-point pen tip 4
The inner wall surface 4f of the caulked portion of the leading edge 4b for holding the ball is formed into a spherical surface of the same shape as the ball, so that mutual contact with the ball pressed via the movable member 8 by the resilient force of the coil spring 7 Naturally, the surface makes a surface contact instead of a linear contact, so that the prevention of ink leakage from the tip of the chip increases the structural reliability. In addition, it should be noted that, due to writing, fibers such as paper adhere to the contact surface between the inner wall surface of the caulked portion and the ball, and the degree of close contact between the inner wall surface of the caulked portion and the ball surface is temporarily impaired, and the written portion is exposed to the open air. The water-based ink 2 used in the present invention described above even when exposed to water.
In combination with the improved characteristics of the above, that is, the dry-up resistance, the anxiety of ink leakage from the tip of the chip and the anxiety that the writing performance deteriorates can be solved.

Further, as shown in FIG.
4 is an opening 4 in which the ink passage hole 4e is opened at the rear hole 4d.
h is formed in a perfect circle, and the connecting portion 8h connected to the core portion 8d in the vicinity of the tip 8c of the ball pressing portion 8a of the movable member 8 is formed on a tapered surface. The opening 4h of the tip 4 and the connecting portion 8h of the movable member 8 come into contact with each other, and a new valve mechanism for preventing the ink from flowing out from the tip of the tip operates. The configuration of the new valve mechanism of the present invention for preventing ink from flowing out when the ball falls off is exemplified by one configuration in the embodiment, and the ink conduction hole 4e of the ballpoint pen tip 4 is connected to the rear hole 4d. A valve portion (not shown) that replaces the connecting portion 8h may be provided around the opening 4h to be opened and near the tip 8c of the ball pressing portion 8a of the movable member 8 to constitute a new valve mechanism with another configuration. What can be done is, of course.

Although the ball-point pen refill of the present invention is intended to be mounted on a knock-type ball-point pen, there is no problem in using the ball-point pen refill in a barrel of a cap-type ball-point pen. However, in the refill used for the cap-type ball-point pen, there is an air supply hole for supplying air corresponding to the ink consumed for writing at the tip end side (the air intake in the embodiment of the present invention is a tail plug). There is a type in which a cap is fitted to prevent ink evaporation. This type of refill is a chip holder member 9 shown in FIG.
In this case, the abutting flange 9h abuts against the step of the shaft cylinder of the other party to block the outside air flow in the front-rear direction. In the ink container 1 shown in FIG. The connecting portion 1b of 1d comes into contact with the step portion of the barrel, and the outside air flow in the front-rear direction is shut off. Therefore, in order to be applicable to this type of cap-type ballpoint pen, for example, in the case of using the tip holder member 9 shown in FIG.
It is preferable to provide an air groove 9j extending in the axial direction and opening at the outer peripheral surface. As a result, the air that is pressurized when the cap is fitted to the barrel is passed through the air groove 9j and flows into the rear barrel having a large volume, so that adverse effects on the performance of the refill can be avoided. Become.

As described above, the ballpoint pen refill of the present invention takes appropriate measures from both the ink composition side and the refill structure side which complements the properties of the ink, and is good even when the writing portion is exposed to the outside air. Even if the ball is dropped, the ink can be completely prevented from leaking from the tip of the tip even when the ball is dropped. By preventing the ink from flowing out, a ball-point pen refill directly filled with water-based ink that can be used for a knock-type ball-point pen with security can be obtained.

[0041]

According to the present invention, when the ink is imparted with a shear thinning property, the ink has a high viscosity in a static state. Therefore, the ink does not require a member such as an ink occluding body, a relay core or a pen core having an ink discharge adjusting function. There is an advantage that the ink can be directly filled in the storage cylinder and the viscosity of the ink is instantaneously reduced by the rotation of the ball at the time of writing, and a clear handwriting can be obtained with a smooth writing feeling,
For the problem that the ball may fall off due to ink leakage or impact from the tip of the chip, a sealing member (using an elastic member such as silicone rubber) that seals the tip of the chip is fitted in the cap. The cap-type ballpoint pen aiming at (1) is commercialized first, and the market evaluation is extremely good. Therefore, the present invention is applied to a knock-type ballpoint pen in which the writing unit is exposed to the outside air and the tip is stored in the barrel in a downward state, and the writing unit protrudes and retracts from the opening at the tip of the barrel by a pressing operation on the pressing member. The effect of the present invention completed in a ballpoint pen refill that can be achieved is no different from the cap type that was commercialized earlier in terms of performance, and from the inconvenience of removing and fitting the cap by using this for the knock type It is open and adds more functionality and convenience, so that new products such as knock-type ballpoint pens can be developed.
The effect is immense.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a ballpoint pen refill according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a ballpoint pen refill according to a second embodiment of the present invention.

FIG. 3 is a longitudinal cross-sectional view of a first embodiment in which a front end portion of a refill is notched and enlarged.

FIG. 4 is a longitudinal sectional view of the refill tip of the second embodiment with a notch enlarged.

FIG. 5 is a process drawing in which only a tip end portion of the ball-point pen tip manufacturing method of the present invention is cut away in vertical section.

FIG. 6 is an explanatory view in which a tip end portion showing a state at the time of dropping of a ball is partially cut away in vertical section.

FIG. 7 is a longitudinal sectional view showing a conventional ballpoint pen refill.

FIG. 8 is a longitudinal sectional view showing a conventional ballpoint pen.

[Description of Signs] 1 Ink storage cylinder 1a Tip hole 1b Connecting portion 1c Small diameter portion 1d Large diameter portion 2 Water-based ink 3 Ink follower 4 Ballpoint pen tip 4a Ball house 4b Tip edge 4c Ball seat 4d Rear hole 4e Ink communication hole 4f Inside caulking portion Wall surface 4h Opening portion 5 Tail plug 6 Ball 7 Coil spring 8 Moving member 8a Ball pressing portion 8b Ink rectifying portion 8c Tip portion 8d Core portion 8e Rear end surface 8f Ink passage 8h Connecting portion 9 Tip holder member 9a Tip hole 9b Ink circulation hole 9c Rear end face 9d Fitting part 9e Horizontal groove 9f Vertical groove 9g Partition part 10 Ink storage member 11 Ink partition member 11c Spring receiving part 11d Rear end face 11e Ink circulation hole 11f Horizontal groove 11g Vertical groove H Hammer rod Q Clearance T Caulking jig

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuhiko Sasaki 174-2-2, Naganumacho, Isesaki-shi, Gunma Inside the pilot Isesaki Plant Co., Ltd. (72) Inventor Takashi Ono 174-2-2, Naganuma-cho, Isesaki-shi, Gunma Pilot Isesaki Plant Inside

Claims (4)

[Claims] An ink container having a cylindrical ink storage member integrated with a fitting portion of a chip holder member having an ink circulation hole communicating with a tip end hole has a high viscosity in a static state, but has a high viscosity. A water-based ink provided with a shear-thinning viscosity, the viscosity of which decreases with rotation, and an ink follower that follows the consumption of the ink and prevents the backflow of the ink are stored at the rear of the ink, and the ballpoint pen tip is fitted into the tip hole. At the same time, a coil spring that constantly presses the ball is disposed directly or via a movable member on the inner wall surface of the caulking portion at the leading edge that holds the ball, and a tail plug provided with ventilation means is fitted at the rear end. In a ball-point pen refill filled directly with ink, the water-based ink (2) imparted with shear thinning contains 2 to 10% by weight of a dye and 20 to 30% of a moisturizing wetting agent.
Wt%, urea 5-10 wt%, crosslinked acrylic acid polymer 0.2-0.4 wt%, xanthan gum 0.05-0.
An ink comprising 2% by weight, 1.0% to 5.0% by weight of sorbit, and the balance water, wherein the tip holder member ( 9 ).
Is a tip hole (9) into which the ballpoint pen tip ( 4 ) is fitted.
a) having an ink circulation hole (9b) which does not reach the rear end face (9c) communicating with the ink storage member (10); And a longitudinal groove (9f) extending in the axial direction and serving as an ink flow passage communicating with the lateral groove and the rear end face.
A ball-point pen refill directly filled with water-based ink, wherein a partition wall (9 g) including a rear end surface for regulating the amount of ink flowing through the vertical groove is formed. 2. An ink container having a small-diameter portion opening at the front end and a large-diameter portion opening at the rear end is provided with a shear thinning viscosity that has a high viscosity in a static state but decreases with the rotation of the ball. A water-based ink and an ink follower that follows the consumption of the ink and prevents the backflow of the ink are stored in the rear part of the ink, and a ball-point pen tip is fitted into the front-end hole thereof, and a tip edge for holding the ball is swaged. A coil spring that constantly presses the ball is provided directly or via a movable member on the inner wall surface, and a tail plug provided with a ventilation means is fitted at the rear end thereof. The water-based ink (2) provided with viscosity contains 2 to 10% by weight of a dye and 20 to 30% of a moisturizing wetting agent.
Wt%, urea 5-10 wt%, crosslinked acrylic acid polymer 0.2-0.4 wt%, xanthan gum 0.05-0.
An ink comprising 2% by weight, 1.0% to 5.0% by weight of sorbit, and the balance water, wherein the ink container ( 1 ) is formed of a metal material and a ballpoint pen tip ( 4 ) of the ink container is fitted. The connecting portion (1b) of the small-diameter portion (1c) to be attached and the large-diameter portion (1d) for storing ink has an ink flow passage penetrating in the axial direction, and has a front end face behind the coil spring (7). An ink partition member ( 11 ), which is formed as a spring receiving portion (11c) for supporting the end, and has an opening portion of an ink flow passage for regulating the flow of ink formed as a rear end surface (11d), is provided. The ink flow passage of the partition member
Ink holes (11) that open at the leading end and do not reach the trailing end
e), a lateral groove (11f) drilled toward the axis in the radial direction communicating with the ink flow hole, and a longitudinal groove (11g) extending in the axial direction communicating with the lateral groove and the rear end face. A ballpoint pen refill filled with water-based ink. 3. A caulking jig (T) is pressed against a tip edge (4b) with the ball (6) positioned in the ball house (4a) by the ballpoint pen tip ( 4 ), and a caulked portion is formed on the ball. Rolling and caulking are performed to form the inner wall surface (4f) of the caulked portion into a spherical surface of the same shape as the ball.
The upper surface of the ball exposed from the tip edge is hammer rod (H)
The ball seat (4c) is plastically deformed toward the rear end by a predetermined amount to secure a clearance (Q) with the ball in the ball house, and the rear hole (4c).
An ink passage hole (4e) penetrating through d) is provided at a predetermined length in the axial direction so that an opening (4h) with the rear hole is formed in a perfect circle. A ball-point pen refill directly filled with the aqueous ink according to claim 2. 4. A ball pressing portion (8a) including a tip (8c) having a diameter smaller than the diameter of an ink conducting hole (4e) of a chip 4 abutting the tip surface of the ball (6), and an ink passage (8f). Is provided on the outer periphery of the movable member ( 8 ), which is formed by an ink rectifying portion (8b) having a rear end surface (8e) in contact with the coil spring (7). The ball-point pen refill according to claim 3, wherein the connecting portion (8h) connecting to the core portion (8d) having a diameter larger than the diameter of the ink conducting hole is formed on the tapered surface.