JP2003220791A - Gas-pressurized writing utensil and refill for writing utensil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas-pressurized writing utensil which is simply structured with a small number of parts and certainly prevents a gas from leaking and can make a wide range of selection of resins based on moldability, economy and the like and reduce a manufacturing cost, and a refill for a writing utensil. <P>SOLUTION: The gas-pressurized writing utensil comprises a tubular body 14, with an open rear part, which has a writing tip 10 fitted to the apex and internally stores an ink 12 to be supplied to the writing tip 10 and a storage barrel 18, with a closed rear end, which has a space formed communicating with the open rear part 14b of the tubular body 14 and envelops at least part of the tubular body 14. The storage barrel 18 has a gas barrier layer (18c and 18d) exhibiting low gas permeability and gas impermeability formed on at least part of the inner surface or outer surface of the storage barrel 18. Further, the space formed between the tubular body 14 and the storage barrel 18 is hermetically filled with a pressurizing gas. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a gas pressure type writing instrument and a refill for a writing instrument.

[0002]

2. Description of the Related Art Heretofore, various types of gas pressurizing writing instruments have been known in which a pressurized gas is sealed in a barrel and the pressure of the gas is used to push out the ink inside. This gas-pressurized writing instrument has the function of pushing out the ink by the pressurized gas inside, so that writing is possible smoothly and upward writing is also possible (normal ballpoint pens use air from the tip of the pen). Swallowed, the ink will flow back). The basic structure of this pressure ball-point pen is that the tip is a pen tip, an ink storage cylinder connected to the tip to store ink and pressurized gas therein, and a tail provided at the rear end of the ink storage cylinder. It consists of a stopper. As the ink storage cylinder, some technologies using transparent resin have been disclosed in order to make the remaining amount of internal ink visible. However, there is a problem that gas leaks depending on the resin used. That is, there is a problem that the pressurized gas passes through the resin and leaks from the inside of the ink containing cylinder to the outside.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art. A gas pressure type writing instrument and a refill for a writing instrument capable of preventing gas leakage with a simple structure having a small number of parts. The purpose is to provide.

[0004]

In order to solve the above problems, the following inventions are provided. The invention according to claim 1 is
A gas-pressurized writing instrument comprising a tube body having a writing tip provided at its tip and containing ink to be supplied to the writing tip inside and a closed rear end, and a pressurized gas sealed in the tube body. Thus, the present invention relates to a gas pressurizing writing instrument, wherein a gas barrier layer having low gas permeability or gas impermeable property is formed on at least a part of the inner surface or the outer surface of the tube body. The invention according to claim 2 is
The gas pressurizing writing instrument according to claim 1 is limited, and the material of the gas barrier layer is ethylene vinyl alcohol copolymer (EVOH). The invention according to claim 3 limits the gas pressure writing instrument according to claim 1, and the material of the tube body is polyethylene terephthalate (PET), nylon, polyethylene naphthalate (PEN), or polybutylene. Any one of terephthalate (PBT) is used, and the material of the gas barrier layer is ethylene vinyl alcohol copolymer (E
VOH). The invention according to claim 4 limits the gas pressure writing instrument according to claim 1, wherein at least a part of the tube body is made of transparent or translucent resin, and the internal ink is visually recognized. It is characterized by being possible. According to a fifth aspect of the present invention, a space is provided in which a writing tip is provided at the tip, ink for supplying to the writing tip is housed inside, and a tube body that is open at the rear side and the opening portion at the rear side of the tube body communicates with each other. And at least a part of the tube body, and a housing cylinder closed at the rear end, wherein the housing cylinder has a low gas permeability or at least a part of its inner surface or outer surface. A gas pressurizing writing instrument characterized in that a gas barrier layer exhibiting gas impermeability is formed, and a pressurizing gas is enclosed in a space provided between the tube body and the accommodating cylinder body. The invention according to claim 6 limits the gas pressurizing writing instrument according to claim 5, wherein the tube body is enclosed in the housing cylinder by joining the housing cylinder and the writing tip. The feature is that the tube body is prevented from coming into contact with the outside air. The invention according to claim 7 limits the gas pressurizing writing instrument according to claim 5, wherein a joining member for maintaining the airtightness of the space between the tube body and the accommodating cylinder is a tube body. It is characterized by being provided between the housing and the housing. The invention described in claim 8 is claim 5
The gas-pressurized writing instrument according to claim 1 is limited, and a joining member for maintaining the airtightness of the space between the tube body and the containing cylinder is provided between the containing cylinder and the writing tip. It is characterized in that the tube body is included in the housing cylinder so that the tube body does not come into contact with the outside air. The invention according to claim 9 limits the gas-pressurized writing instrument according to claim 7 or 8, wherein at least a part of the inner surface or the outer surface of the joining member has low gas permeability or gas impermeability. A gas barrier layer exhibiting properties is formed. The invention according to claim 10 limits the gas pressurizing writing instrument according to any one of claims 5 to 9, and the material of the gas barrier layer is an ethylene vinyl alcohol copolymer (EVOH). It is characterized by being.
The invention described in claim 11 limits the gas pressurizing writing instrument according to any one of claims 5 to 9,
The material of the container is polyethylene terephthalate (PET), nylon, polyethylene naphthalate (P
EN) or polybutylene terephthalate (PBT), and the material of the gas barrier layer is ethylene vinyl alcohol copolymer (EVOH). The invention according to claim 12 is the invention according to claims 7 to 11.
The gas pressurizing writing instrument according to any one of items 1 to 4 is limited, and the joining member is integrally formed with the accommodating cylinder. The invention described in claim 13 is claim 5
The gas pressurizing writing instrument according to any one of 1 to 12 is limited, and ink is brought into contact with the storage cylinder or / and the joining member (the storage cylinder or the joining member, or the storage cylinder and the joining member). Characterized by not doing. The invention described in claim 14 limits the gas pressurizing writing instrument according to any one of claims 5 to 13, and at least a part of the tube body and the containing cylinder is transparent or translucent. It is made of resin and the internal ink is visible. The invention described in claim 15 limits the gas pressurizing writing instrument according to any one of claims 5 to 14, and the volume of a space provided between the tube body and the housing cylinder body. Is 2 to 10 times the volume of the ink contained in the tube body in the initial state, and the pressure in the space is 0.15 MPa to 0.6 MPa in the state in which the ink has been consumed immediately before the end of writing. It is characterized in that a gas is sealed in. According to a sixteenth aspect of the present invention, the writing tip, the tube body and the accommodating cylinder body according to the fifth to fifteenth aspects are integrated into a refill that can be detachably mounted in the shaft cylinder of the writing instrument. Refills for writing instruments.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. (Embodiment 1) In Embodiment 1, as shown in FIG. 1, a writing tip 10 made of a metal holding a writing ball at its tip or a resin preferably having gas impermeability or low permeability is provided at a tube body tip 14a. Provided on the inside of the writing chip 10
Various kinds of ink 12 such as oil-based ink, water-based ink or ink having shear thinning property to be supplied to the ink (follower can be provided in the ink rear portion) and a rear (rear end) open cylindrical resin. Tube body 14
And a closed closed rear tubular body 18 that includes a space 16 that communicates with the rear open portion 14b of the tube body 14 and that contains the tubular body 14.
Is made of a material having low gas permeability or gas impermeability, and a pressurized gas (dry air or nitrogen gas) is enclosed in a space 16 provided between the tube body 14 and the housing cylinder 18. It is a gas pressure writing instrument.

In this gas pressurizing writing instrument, a joining member 20 for maintaining the airtightness of the space 16 between the tube body 14 and the containing cylinder 18 is provided (in this embodiment, the joining member 2 is used).
0 is bonded to the writing chip 10 and the housing cylinder 18), and the bonding member 20 is formed of a material having low gas permeability or gas impermeable property. Note that “joining” is a concept including fitting, adhesion, welding, and the like.

The joining member 20 has a substantially hollow cylindrical shape having a front end portion 20a that expands like a flange (having a through hole 30 penetrating therethrough), and most of the other parts are the front end portion of the accommodating cylindrical body 18. However, the flange-like front end portion 20a prevents the tube body 14 from further diving.

A joining member 20 formed of a material exhibiting low gas permeability or gas impermeability is provided for holding the airtightness of the space between the tube body 14 and the accommodating cylinder 18 and the accommodating cylinder 18 and the writing tip. 10, the writing tip 10 is inserted into the insertion hole 30 provided in the joining member 20, and the tube body 14 connected to the rear end of the writing tip 10 is accommodated in the accommodating cylinder body 18.
It is contained inside so that the tube body 14 does not come into contact with the outside air. By doing this, the tube body 14
The material selection range is widened, and for the tube body 14, a resin material other than low gas permeability or impermeability can be used. As a result, for example, oil resistance, liquid resistance, transparency,
A material having high moldability and high clear drain property can be used. For example, polypropylene (PP), polyethylene (PE) or the like can be used. The joining member 20
By coloring the ink, it becomes possible to judge the ink color.

Here, the periphery of the joining member 20 will be described in detail. In the periphery of the joining member 20, as shown in FIG. 2, the tapered outer peripheral surface of the tapered front end of the chip holding body 24 faces the tapered inner peripheral surface of the front portion 22f of the exterior member 22. The writing tip 10 has a step contact portion 10b which is a step.
The tip holding body 24 having a locking portion 24a for restricting the forward movement of the writing tip 10 is formed on the tip 10a of the writing tip 10. Is provided in front of the barrel 28 (on the side of the writing tip 10). More specifically, the tip holder 24 covers the joint between the writing tip 10 and the joint member 20 and the joint between the housing cylinder 18 and the joint member 20 with the tip 10a of the writing tip 10 facing the outside. However, it is locked to the housing cylinder 18. The chip holder 24 can be locked to the joining member 20. When the tip holder 24 is locked to the joining member 20, it is desirable to cover the joining portion between the writing chip 10 and the joining member 20 with the tip holder 24. Further, when the housing cylinder 18 is joined to the writing chip 10 without providing the joining member 20, it is desirable to cover the joining portion with the tip holder 24. By providing such a tip holder 24, it is possible to prevent the writing tip from popping out due to the pressurized gas.

A reduced diameter portion 10d having a smaller diameter is provided behind the writing tip 10. This reduced diameter portion 10
The diameter of d is smaller than that of the large-diameter portion 10e in front of the stepped portion 10c. The reduced diameter portion 10d is thus formed by the step portion 1
It is not limited to the case of forming at 0c as a boundary, and it is also possible to form so that the diameter becomes gradually smaller by taper or the like. The rear end of the reduced diameter portion 10d has a tube body 14
Inserted and fixed. Further, in the portion of the reduced diameter portion 10d, which is sandwiched between the step portion 10c and the fixing portion of the tube body 14 and the reduced diameter portion 10d, the front inner peripheral surface of the joining member 20 (in the through hole 30 The peripheral surface) is welded and joined by heat to maintain airtightness. Also, by joining in this way,
It also prevents the writing tip 10 from coming off the tube body 14. If the joining member 20 is not provided, the housing cylinder 18
Can be directly joined to the reduced diameter portion 10d.

The connecting member 20 or the containing cylinder 18 is replaced with the reduced diameter portion 1
By joining to 0d, it has the following effects. In general, in a writing instrument, it is preferable that the diameter of the parts arranged around the writing tip 10 is smaller (the diameter is preferably smaller as it is closer to the pen tip). This is because when a part with a large diameter is placed, the part interferes with it, and the pen tip cannot be seen sufficiently (writing is poor) at the time of writing, and the smartness is lost, which is not desirable in appearance. Because. When joining the joining member 20 and the housing cylinder 18, it is possible to join the large diameter portion 10e. However, the large-diameter portion 10e is closer to the pen tip and has a larger diameter. Therefore, when joined to the large-diameter portion 10e, the joining member 20 and the accommodating cylinder are located closer to the pen tip, so that these parts may hinder the visibility of the pen tip during writing. is there. In addition, the appearance is not smart, which is not preferable. At the rear of the writing tip, a reduced diameter portion with a reduced diameter is provided, and the rear end of the reduced diameter portion is fixed to the tube body,
By joining the joining member or the housing cylinder to the reduced diameter portion, it is possible to make the pen tip easy to see and to make the appearance smart.

A metallic ring 25 is interposed between the joining member 20 and the accommodating cylinder 18, and the ring 25
Induction heating (electromagnetism) or the like is performed to heat the joining member 20 and the housing cylinder 18 and then to cool and join (weld) to maintain airtightness.

A gap d is provided between the engaging portion 24a of the tip holder 24 and the tip contact portion 10b.
In the present embodiment, when the bonding member 20 or the like swells or expands due to moisture absorption or the like, the bonding member 20 may come into contact with the chip holder 24 and the chip holder 24 may come off. It becomes difficult to prevent the writing tip 10 from unexpectedly popping out due to the pressurized gas. Therefore, in the present embodiment, the gap d is provided to prevent the above-described problem that occurs when the joining member 20 abuts on the chip holder 24. The chip holder 24 and the housing cylinder 18 are provided with a chip holder rear locking portion 27b and a housing cylinder rear locking portion 27a, respectively. Has been done.

In the present embodiment, the joining member 20 and the housing cylinder 18 are joined by welding by heat, but the rear engaging portion 27 is a portion other than this joining portion (specifically, the joining portion). (In front of). Here, the rear locking portion 27
The term "retains" the tip holding body rear locking portion 27b or the housing cylindrical body rear locking portion 27a, which locks the chip holding body provided on the housing cylindrical body or the joining member. For example, there are locking protrusions and recesses. When the joining member 20 and the containing cylinder 18 are joined by welding by heat, the containing cylinder 18 and the like are likely to be thermally deformed. If the chip holder 24 is locked at such a position, a sufficient locking force may not be obtained. By providing the rear locking portion 27 at a position other than the joining portion, it is possible to obtain a sufficient locking force for the chip holder.

Further, an airtight holding joint portion 3 for holding the airtightness of the space between the tube body 14 and the housing cylinder 18
1 are concentrated around the writing chip 10. Here, the “airtightness holding and joining point” means the joining point between the writing tip 10 and the housing cylinder 18, and the writing tip 10 and the joining member 20.
4 and the joining portion between the housing cylinder 18 and the joining member 20, and when the tail plug 26 is provided at the rear end of the housing cylinder 18 as shown in FIG. It is a joint part or the like, and is a part that joins parts together and blocks the outside air from the inside of the housing cylinder.

For example, if the tail plug 26 or the like is attached to the rear end of the accommodating cylinder 18, it is necessary to take measures to prevent the tail plug 26 from popping out by the pressurized gas. If there are a plurality of such joints, it is necessary to take measures to prevent them from popping out, which hinders efficient design and increases the cost. On the other hand, since the writing chip 10 is usually made as a separate component, it must be joined to another component. Therefore, the writing tip is always provided with at least one joining portion. If other joints are provided around this writing chip, safety measures such as pop-out measures need only be provided only around this writing chip, and the number of places for pop-out prevention measures can be reduced. For example, in FIG. 1, the chip holder 24 corresponds to a component required to prevent popping-out, and the pop-out countermeasure is realized by molding the housing cylinder 18 into one cup-shaped component.

The chip holder 24 can be colored not only transparent but also opaque or semi-transparent. In this way, ink stains inside the writing instrument (writing tip 1
It is possible to prevent the outside of 0 from being easily seen from the outside at the time of assembly, which improves the appearance and appearance quality. Further, the opaque or semi-transparent coloring can be displayed in color, and at that time, it is desirable that the color corresponds to the ink. The housing cylinder 18 may be located inside the joining member 20. Further, the fixing of the joining member 20 and the fixing between other members are not limited to the welding fixing, and it is conceivable that the fixing is performed by various fixing means such as fitting and adhesion. It is also conceivable to mold the joining member in two colors. In addition, as an adhesive material at the time of adhering, a material having a sealing property is preferable, and examples thereof include a polyvinyl alcohol solution, a two-component mixed epoxy, and hot melt. At the time of adhesion, it is better to use together with an undercut seal (fitting) in order to ensure the gas barrier property. It is extremely difficult to select an adhesive having both sealing property and adhesive property. Therefore, it is desirable that the joining is performed by welding.

The housing cylinder 18 and the chip holder 24 are surrounded by a moisture-proof exterior member 22. The exterior member 22 is divided into front and rear parts (indicated by a front part 22f and a rear part 22r), and encloses the accommodating cylinder 18 and is integrated by screwing, crimping, or adhering at the dividing part 22b. If possible, it is advantageous to seal the dividing portion 22b.

By forming the accommodating cylinder 18 or the like with a material exhibiting low gas permeability or gas impermeability, it is possible to provide a gas pressure type writing instrument. However, this gas low permeability or gas impermeable property can be provided. Most of the materials shown are (for example, ethylene vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyacrylonitrile (P
AN), nylon), when the relative humidity of the surroundings increases,
The gas permeability increases, and the gas easily permeates. For example, ethylene vinyl alcohol copolymer (EVOH) has a very high barrier in a dry state, but the barrier property decreases as the relative humidity increases. By covering the periphery of the tube body and / or the housing cylinder body with the moisture-proof exterior member 22, it is possible to suppress the deterioration of the barrier property.
It is most preferable that the portion covered with the exterior member 22 covers the entire portion of the material exhibiting low gas permeability or gas impermeability, but it is also possible to cover a portion thereof. When covering a part, it is preferable that the user's hand touches it, and the most preferable position is the grip portion (grip portion 3).
2). The exterior member may have a closed structure in which the inside is shielded from the outside air. By doing so, heat resistance and moisture resistance can be improved. The hermetically sealed structure is formed by joining (fitting, adhering, welding, etc.) the exterior member to the housing cylinder, the chip holder, the joining member, the tail plug, or the like.

The exterior member 22 has more heat resistance and / or moisture resistance than the housing cylinder 18. As described above, when the low gas permeability or gas impermeable resin used for the housing cylinder 18 is selected from various resin materials, the influence of hand sweat on the shaft when the user holds and writes is taken into consideration. It is necessary, or it is necessary to consider when the writing instrument becomes hot on the top surface of the dashboard of the vehicle. However, it is difficult to select a resin material that has low gas permeability and heat resistance and humidity resistance. Therefore, when the housing cylinder 18 containing the gas is selected from various resin materials showing low gas permeability or gas impermeability, if the exterior member 22 has heat resistance or moisture resistance, It is not necessary to take such heat resistance or moisture resistance into consideration in the containing cylinder 18 itself, so that the range of resin selection is expanded and the functionality is improved. As the resin selected for the exterior member 22,
Polypropylene (PP), polyethylene (PE), polyolefin, cyclic polyolefin, polyethylene terephthalate (PET), polyethylene naphthalate (PE
N), vinylidene chloride and the like are preferable. Especially when the accommodating cylinder is an ethylene vinyl alcohol copolymer (EVOH), polypropylene (PP) or polyethylene (P
E) It is preferable to use a resin. This is because it is excellent in heat resistance, rigidity and adhesion. Further, while maintaining the gas barrier effect, it is possible to improve the moisture proof property and the internal visibility (light transmittance) such that the remaining amount of the internal ink can be easily grasped.

Although the exterior member 22 has a shaft cylinder structure which is a separate body from the housing cylinder 18, the exterior member 22 is not limited to being a separate body from the housing cylinder 18, and the housing cylinder 18 is not limited thereto.
It is also possible to form the exterior member 22 so as to integrally cover all or all of the writing chip 10 except the tip 10a (two-color molding, vapor deposition, laminate, etc.). Furthermore, the exterior member 2
Of the two, the thickness of the grip portion 32 gripped by the user is made larger than the other portions. The grip portion 32 held by the user is most affected by the user's hand sweat. If the thickness of this portion is made larger than that of the other portion of the exterior member, it has the effect of reducing the influence on the housing cylinder 18 inside the exterior member. The method for increasing the wall thickness is not limited to simply increasing the wall thickness, but may be a method of attaching a grip 33 which is a separate component as in the embodiment shown in FIG.

Further, when heated by incineration or the like, the accommodating cylinder 18 is first decomposed to let the enclosed gas escape to the outside of the space. In the present specification, disassembly means that the storage cylinder 18 is melted, cracked or cracked, a hole is formed, or if there is a joint, the joint is removed. . First, the containing cylinder 18
Since the pressurized gas can be discharged to the outside by decomposing, the pressure applied to the writing tip 10 can be reduced, and the risk of the writing tip 10 being blown out (jumping out) by the pressure can be reduced. .

In this case, it is preferable that the material of the chip holder 24 is more heat-resistant than the accommodating cylinder 18, for example, polypropylene (PP), polyethylene (PE), polybutylene terephthalate (PBT), Cyclic polyolefin, polyethylene terephthalate (PE
T), polyoxymethylene (POM), polyethylene naphthalate (PEN) and polyvinyl chloride are suitable.

As the material used for the accommodating cylinder 18 and the joining member 20, for example, a gas low permeability or gas impermeable material such as ethylene vinyl alcohol copolymer (EVOH), nylon, transparent nylon, polyethylene terephthalate. (PET) can be used, and ethylene vinyl alcohol copolymer (EVOH) is particularly preferable. The reason will be described later.

A tip holder 24 is provided which also prevents the writing tip 10 from coming off, and even if the tip holder 24 is incinerated after use, the rigidity of the housing cylinder 18 drops at a predetermined temperature and gas leakage occurs. Since the gas pressure in the space 16 is released, the writing tip 10 does not come out vigorously from the writing instrument or the front of the refill.

The pressurized gas sealed in the space 16 may be nitrogen (N ₂ ) gas or air and has a humidity of 6%.
Dry nitrogen gas of 0% (25 ° C.) or less and dry air are preferable.

Further, the volume of the space 16 provided between the tube body 14 and the accommodating cylinder body 18 is such that the tube body 1 is in the initial state.
The volume of the ink contained in No. 4 is 2 to 10 times, and the pressure in the space 16 is 0.15 MPa to 0.6 MPa immediately before the end of writing when the ink is consumed.

The relationship between the volume of pressurized gas and the volume of ink is 2 to
If the volume of the pressurized gas is less than twice the volume of the ink, the volume of the ink is consumed by writing, and the volume of the ink is reduced, so that the force for pushing out the ink is sufficient. This is because the pressure difference between the initial stage and the end stage is large and the pressure change is too large. on the other hand,
This is because if it exceeds 10 times, a wasteful space is required, resulting in a high cost and an appearance problem that the ink amount looks relatively small.

The pressure in the space 16 in the ink consumption state immediately before the end of writing is set to 0.15 MPa to 0.6 MPa. When the pressure is less than 0.15 MPa, the pressure for pushing out ink is insufficient and the writing is smooth. It becomes difficult to obtain a feeling, and it is easy for water to be caught in the writing tip 10 when writing on a wet paper sheet, and furthermore, water easily enters the writing tip 10 when dropped into water. Is. On the other hand, when it exceeds 0.6 MPa, it becomes difficult to prevent ink leakage from the pen tip.

Further, it is preferable that ink does not come into contact with the accommodating cylinder 18 and / or the joining member 20. In this case, it is possible to select the material without considering the ink resistance of the containing cylinder and / or the joining member 20. Here, as described above, "the ink does not come into contact with the containing cylinder 18 or / and the joining member 20" means that the ink is contained in the containing cylinder 1.
8 and / or not only the fact that it does not come into contact with the joining member 20 at all, but the concept also includes the case where a small amount of ink adheres. For example, ink may adhere to the housing cylinder 18 and the joining member 20 when manufacturing a writing instrument. Such an adhered state also indicates that "the ink is contained in the cylindrical body 18 and / or the joining member 2
Do not touch 0 ”.

It is preferable that at least a part of the tube body 14 and the accommodating cylinder body 18 be made of a transparent or translucent resin because the ink remaining amount can be easily confirmed. Further, for the same reason, at least a part of the exterior member 22 and the chip holder 24 can be made transparent. In addition, the writing tip, the tube body and the containing cylinder body,
The refill can be integrated and detachably mounted in the barrel of the writing instrument. Further, the writing tip, the tube body, the accommodating cylinder body, and the exterior member can be integrated into a refill.

(Second Embodiment) FIG. 3 is a second embodiment showing a modification of the shape of the joining member 20. In the second embodiment, the joining member 20 is joined to the tube body 14 and the housing cylinder body 18, so that most of the tube body 14 is housed in the housing cylinder body 1.
It is included in 8.

When a resin material other than low gas permeability or impermeability is used for the tube body 14, in order to prevent gas permeation from the housing cylinder 18 through the tube body 14, low gas permeability It is preferable to cover the front end of the tube body 14 with a chip holder 24 made of a resin material that is permeable or impermeable. More specifically, the chip holder 24 is
The writing chip 10 and the housing cylinder 18 are joined (bonding methods include heat welding, ultrasonic welding, and adhesion) to prevent leakage of pressurized gas. The chip holder 2
No. 4 does not necessarily require the use of a resin material having a low gas permeability or an impermeable gas when a resin material having a low gas permeability or an impermeable gas is used for the tube 14, and the joining such as welding is not always necessary. I don't need it. Other configurations are basically similar to those of the first embodiment shown in FIG.

(Embodiment 3) In FIG. 4, the joining member 20 is extended rearward to be integrally molded with the housing cylinder 18, and the tail plug 26 is
It shows the third embodiment joined (fitted) with the housing cylinder 18 and the exterior member 22. The housing cylinder 18 and the joining member 20 are
In this way, it is possible to combine with other parts such as the tail plug 26 and the like, or it is possible to interpose some other parts. However, the tail plug 26 in this case is required to have low gas permeability or gas impermeability (gas barrier property) except when a gas barrier layer or the like described later is provided, and to prevent some kind of blowout (jumping out) such as welding. Is preferably adopted.

In the present embodiment, the accommodating cylinder 1
8 and the writing tip 10 are joined together to form the tube body 1
All of No. 4 are contained in the containing cylinder body 18 so that the tube body 14 does not come into contact with the outside air. Since the tube body 14 does not come into contact with the outside air, it is possible to use a material that transmits the pressurized gas. Therefore, the selection range of the material of the tube body 14 is widened, and various materials such as a highly transparent material, a material that can be easily molded, and a material that has a good clear drain property can be used.

Although the joining member 20 and the accommodating cylinder 18 are integrally molded as described above, the number of parts can be reduced. When the plug 26 is provided, the number of parts does not change, but it becomes possible to select and design parts with shapes that are easy to mold, and overall costs can be reduced, size can be minimized, and transparency can be increased. can do.

The accommodating cylinder 18 is formed of two parts, and the parts are joined together. The structure is such that a joining part having a joining force smaller than that of the joining part of the writing chip 10 is provided. Is shown. As for the joining portion of the writing tip 10, for example, the writing tip 10 and the tube body 14,
The writing tip 10 and the tip holding body 24, and the writing tip 10 and the accommodating cylinder 18 can be mentioned. The present embodiment is provided with a joining portion joined with a joining force smaller than those joining portions. Examples of such joints include, for example, when the tail plug 26 is provided in the storage cylinder 18 or the tube body 14,
There are a case where the housing cylinder 18 is formed by two parts, and a case where a hole is opened in the housing cylinder 18 and a part of a shape filling this part is joined. It is also conceivable to fill the holes of the housing cylinder 18 with an adhesive or resin. Examples of a method of changing the joining force include changing the amount of adhesive, changing the amount of riding when fitting, and changing the joining area. In the third embodiment, the tail plug 26 is provided at the rear end of the housing cylinder 18. The joining force between the tail plug 26 and the containing cylinder 18 is smaller than the joining force between the writing tip 10 and the containing cylinder 18. With such a configuration, even if the gas pressurizing writing instrument of the present invention is heated, the pressurizing gas can be exhausted to the outside by removing the joint part other than the joint force of the joint part of the writing tip 10. The pressure applied to the writing chip 10 can be reduced, and the risk of the writing chip 10 and the ink 12 being blown out (jumping out) due to the pressure can be reduced. The joining force is measured by applying a tensile force in the axial direction to the joint.

In the case where the joining member 20 is provided between the housing cylinder 18 and the writing tip 10 as in the first embodiment shown in FIG. 1, for example, the writing tip 10 and the joining member 2 are provided.
The joining force at the joining point with 0 or the housing cylinder 18 and the joining member 2
0 of the joining forces at the joining points of 0,
It is also possible to provide a joining portion formed with a small joining force.

As the "joint portion formed with a small joining force" as described above, for example, when the tail plug 26 is provided in the storage cylinder 18 or the tube body 14 as in the above, the storage cylinder 1
There are a case where 8 is formed by two parts, and a case where a hole is opened in the accommodating cylinder 18 and a part of a shape filling this part is joined. It is also conceivable to fill the holes of the housing cylinder 18 with an adhesive or resin. Examples of a method of changing the joining force include changing the amount of adhesive, changing the amount of riding when fitting, and changing the joining area. It is also possible to form the housing cylinder 18 from two parts. As a method thereof, when the tail plug 26 is provided on the housing cylinder 18 or the tube body 14, the housing cylinder 18 is formed into two parts.
Examples include a case where the parts are formed and joined, or a case where a hole is made in the housing cylinder 18 and the parts are filled to join the parts.

The joining force of the joining portion between the writing tip 10 and the joining member 20 or the joining force of the joining portion between the housing cylinder 18 and the joining member 20 is smaller than the joining force which is smaller. By providing the location, even if the gas pressure writing instrument is heated, the joining point other than the joining point between the writing tip and the joining member and the joining portion between the housing cylinder and the joining member may be removed. Since the pressurized gas can be discharged to the outside, the pressure applied to the writing tip can be reduced, and the risk of the writing tip 10 and the ink 12 being blown out (jumping out) by the pressure can be reduced.
When there are a plurality of joints, the joint of the writing tip 10 (for example, the joint of the writing tip 10 and the joint member 20 or the joint of the writing tip 10 and the housing cylinder 18).
It is desirable to maximize the bonding strength of the. This is because the joint portion of the writing chip 10 is apt to be weakened and easily blown (jumps out) because the writing load is constantly applied.

As described above, when the accommodating cylinder 18 is first disassembled, when a joining portion having a joining force smaller than the joining force of the joining portion of the writing tip is provided, and at the joining portion between the writing tip and the joining member. In the case of providing a joining portion formed with a joining force or a joining force of the joining portions of the housing cylinder and the joining member that is smaller than the joining force having a smaller joining force, the accommodation cylinder (including tail plug etc.) The material is preferably ethylene vinyl alcohol copolymer (EVOH).

In a warehouse or the like for storing writing instruments, it may reach up to about 50 to 70 degrees depending on the case. There is a problem that if the housing cylinder or the like is decomposed in this temperature range, it cannot be handled as a product. Ethylene vinyl alcohol copolymer (EVOH) does not decompose at these temperatures,
Decomposition starts at a predetermined temperature of 90 degrees or more, which is higher than these temperatures. For this reason, storage and the like are facilitated, and when it is placed in a state such as incineration, it is easily decomposed and the pressurized gas can be discharged to the outside. Furthermore, the gas permeability is low, and it also has the function of making it difficult for the gas to permeate to the outside in a normal state. Other materials include nylon, transparent nylon, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyacrylonitrile (PAN), and the like.

Further, a thin portion 36 may be provided on a part of the housing cylinder 18. In addition, a fourth embodiment of FIG.
It is also possible to form the thin portion 36 on the bottom of the housing cylinder 18 as shown in FIG. With such a configuration, when heated by incineration or the like, decomposition can be promoted first from the thin portion 36 and the pressurized gas can be smoothly discharged. The other configurations are basically the same as those of the first embodiment.

(Embodiment 4 and Embodiment 7) FIG. 5 is a gas pressure type writing instrument in which a moisture-proof layer 18a is integrally provided on the outer surface of the housing cylinder 18 and the outer surface of the joining member 20 by fusion bonding by two-color molding. It is Embodiment 4 which showed. In the present embodiment, the moisture-proof layer 18a is formed on the entire outer surface of these. In this case, since the moisture-proof layer 18a plays a part of the role of the exterior member 22, the exterior member 22 is an optional component.

It is not necessary to provide the moisture-proof layer 18a on the entire surface, but it is preferable to provide the moisture-proof layer 18a at least on an exposed portion in contact with the outside air. Further, when the moisture-proof layer 18a is partially provided, it is preferable to form the moisture-proof layer 18a on the grip portion 32 that is held by fingers.

Here, as the material of the moistureproof layer 18a on the outer surface of the accommodating cylinder 18, polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PE) is used.
T), polybutylene terephthalate (PBT), modified polyethylene terephthalate (m · PPE), cyclic polyolefin, vinylidene chloride, paraffin and the like can be used from the viewpoint of improving moisture resistance. Especially for two-color molding, polypropylene (PP) or polyethylene (PE) is preferable, and the accommodating cylinder is an ethylene vinyl alcohol copolymer (E).
In the case of VOH, it is preferable to use polypropylene (PP) or polyethylene (PE) resin. This is because while maintaining the gas barrier effect, it is possible to improve the moisture proof property and the internal visibility (light transmittance) such that the remaining amount of the internal ink can be easily grasped. Further, it is also excellent in heat resistance, rigidity and adhesion.

When the joining member 20, which is formed as a separate component, is fitted or joined to the housing member 18 for the two-color molding of the moisture-proof layer 18a, the chip holder 24 and the exterior member 22 have a moisture-proof function. Each member 1 except for the case where
It is necessary to perform the two-color molding of the moisture-proof layer on each of 8 and 20. Figure 4
In the case where the joining member 20 is extended rearward to form the housing cylinder 18 as an integrated member as in the third embodiment shown in FIG. 2, the two-color molding of the moisture-proof layer 18a on the outer surface can be collectively performed. Assembling man-hours can be reduced and a completely sealed state can be achieved.

The moisture-proof layer 18a has a thickness of 0.2 to 2.0 mm.
Is appropriate. If it is less than 0.2 mm, the moisture resistance and moldability are poor, and if it is more than 2.0 mm, the shaft diameter becomes large and the usability is poor, and the transparency is poor. The thickness is more preferably 0.4 to 1.0 mm, further preferably 0.5 to 0.8 mm.

Further, although it is originally desirable to hermetically seal, a gap 34 is provided between the exterior member 22 and the accommodating cylinder 18, and a vent hole 35 communicating with the outside is provided in the exterior member 22 so that the gap 34 can be communicated. It may be configured to communicate with the outside through the pores 35. As a method of forming the gap 34, a groove may be formed on the inner surface of the exterior member 22 or the outer surface of the housing cylinder 18. In the present invention, the gap 34 is provided between the exterior member 22 and the housing cylinder 18, and the ventilation hole 35 communicating with the outside is provided in the exterior member 22, so that the housing cylinder 18 is disassembled and leaks. The pressurized gas is smoothly discharged to the outside to prevent the writing tip 10 and the ink 12 from jumping out.

The ventilation hole 35 is provided near the rear end of the exterior member 22. By providing the ventilation hole at the rear end of the exterior member 22 opposite to the joining portion of the writing tip 10, the pressure applied to the front where the writing tip is arranged can be prevented as much as possible. The outer layer member 22 may also be made of a material that decomposes at a predetermined temperature. Other configurations are basically the same as those of the first embodiment.

It should be noted that the writing tip 10 is provided at the front end, the ink 12 to be supplied to the writing tip 10 is accommodated inside, and the rear end is closed, and is made of a material having a low gas permeability or a gas impermeable property. A gas-pressurized writing instrument comprising a tube body (14) and a pressurized gas enclosed in the tube body (14), wherein a moisture-proof layer (18a) is provided on at least a part of the outer surface of the tube body (14) in the same two colors as above. It can also be integrally provided by molding. Embodiment 7 which is this embodiment is shown in FIG. The outer surface may be provided at a portion in contact with the outside air, or it may be provided at the entire surface. The above-mentioned outer layer member 22 can be provided in the tube body 14 of each embodiment shown in FIG. 9.

(Fifth Embodiment and Eighth Embodiment) FIG. 6 shows a fifth embodiment, in which a gas barrier made of a material having a low gas permeability or a gas impermeable property on the inner surface or the outer surface of the housing cylinder 18. The layers 18c and 18d are provided. In this embodiment, the gas barrier layer 18c is provided on the inner surface and the gas barrier layer 18d is provided on the outer surface.

Here, as the material of the gas barrier layers 18c and 18d on the inner surface and the outer surface of the housing cylinder 18, ethylene vinyl alcohol copolymer (EVOH), polybutylene terephthalate (PBT), polyethylene terephthalate (PET) are used. , Polyoxymethylene (POM), nylon, polyethylene naphthalate (PEN), polyacrylonitrile (PAN) and the like can be used. The material of the gas barrier layers 18c and 18d is preferably ethylene vinyl alcohol copolymer (EVOH) because it has very good gas barrier properties and good moldability, and when used in combination with other materials, The ratio is preferably at least 50% or more (less than 100%). The reason is that if it is less than 50%, it becomes difficult to maintain the gas barrier property. Further, the material of the housing cylinder 18 may be any one of polyethylene terephthalate (PET), nylon, polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT), which have moderate gas barrier properties, and these It is also possible to form the gas barrier layers 18c and 18d made of ethylene vinyl alcohol copolymer (EVOH) on the storage cylinder 18 made of the above material. This is because the gas barrier property can be further improved by using any of the materials, and when polyethylene terephthalate (PET) is used, the moisture resistance can be increased and the cost can be reduced. This is because, when nylon is used, the moldability is good and the cost can be reduced, and polyethylene naphthalate (PE
This is because when N) is used, transparency and water resistance can be increased, and when polybutylene terephthalate (PBT) is used, moldability is good and cost can be reduced. Further, the gas barrier layers 18c and 18d are preferably formed thin from the viewpoint of ensuring the visibility of the ink inside, and can be provided on the housing cylinder 18 by using various methods such as printing, transfer, vapor deposition, and painting. . A moisture barrier layer may be provided on the gas barrier layer 18d on the outer surface.

These gas barrier layers (18c, 18d)
The appropriate thickness is 1 μm to 2.0 mm. This is because if it is smaller than 1 μm, the gas barrier property is poor, and if it is larger than 2.0 mm, it becomes expensive and the transparency is deteriorated. The thickness is more preferably 0.1 mm to 1.0 mm, still more preferably 0.4 mm to 0.8 mm.

Various resins other than the above can be used for the housing cylinder 18 which is the base. For example, polypropylene (PP), polyethylene (PE) or the like having high moisture resistance can be used. Further, if the gas barrier layer 18c is provided on the inner surface of the housing cylinder 18, a moisture-proof effect can be obtained by the housing cylinder 18, and the gas barrier layer 18c on the inner surface can serve as a gas barrier, and both the moisture-proof property and the gas barrier property can be obtained. Accommodating cylinder 18
Can be fulfilled only. In this way, the gas barrier layer is less exposed to the outside air when it is provided on the inner surface 18c than when it is provided on the outer peripheral surface 18d (especially when the pressurized gas is nitrogen gas, it is more effective because it does not contain oxygen). ), The functional deterioration of the gas barrier property can be further prevented.

Further, it is also preferable to provide a moisture-proof layer on the inner surface or the outer surface of the joining member 20, and it is possible to obtain the same effect as the case where the housing cylinder 18 is provided with the gas barrier layer.
As the material used for the gas barrier layer of the joining member 20, ethylene vinyl alcohol copolymer (EVOH), polybutylene terephthalate (PB) is used as in the above case.
T), polyethylene terephthalate (PET), polyoxymethylene (POM), nylon, etc., and various resins (polypropylene (PP), polyethylene (PE), etc.) are used for the joining member 20 itself which is the base. You can

Further, if the housing cylinder 18 and the joining member 20 are integrally molded, the gas barrier layer can be provided at one time, and the number of steps is reduced as compared with the case where the gas barrier layer is formed separately.
Moreover, since there is no joint between the joint member 20 and the housing cylinder 18, the gas barrier property can be improved.

Although the gas barrier layer can be provided in a part, it is preferable to provide the gas barrier layer in its entirety in order to obtain the effect of preventing gas leakage for a long period of time. Further, the gas barrier layer may be either the inner surface or the outer surface of the housing cylinder 18. In order to obtain the effect of preventing gas leakage for a long time, it is preferable to provide it on both sides. The rest of the configuration is basically the same as that of the first embodiment shown in FIG.

It should be noted that the writing tip 10 is provided at the tip, the ink 12 to be supplied to the writing tip 10 is accommodated inside, and the tube body 14 closed at the rear end, and the addition inside the tube body 14. A gas pressure type writing instrument comprising a pressurized gas, wherein a gas barrier layer showing low gas permeability or gas impermeability is formed on at least a part of the inner surface or the outer surface of the tube body 14 in the same manner as described above. It is also possible to form it like Embodiment 8 shown in FIG. The gas barrier layer may be provided on both the inner surface and the outer surface, or may be provided only on the portion in contact with the outside air. Further, it is possible to provide all of them.

(Embodiments 6 and 9) FIG.
The moisture-proof layer 18e is transferred or printed on the entire outer surface of 8.
Alternatively, it is a sixth embodiment showing a gas pressure type writing instrument formed by coating or vapor deposition. The moisture-proof layer 18e may be provided on the whole as described above, or may be provided on a part thereof. In this case, the grip portion 32 that is gripped by the fingers
Is desirable.

A moistureproof layer 18e is also formed on the outer surface of the joining member 20. It is more preferable that the moisture-proof layer 18e is formed on the entire surface, but it is preferable that the moisture-proof layer 18e is provided at least at a portion in contact with the outside air.

Here, as the material of the moisture-proof layer 18e on the outer surface of the housing cylinder 18, polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PE) is used.
T), polybutylene terephthalate (PBT), modified polyethylene terephthalate (m · PPE), polyethylene naphthalate (PEN), vinylidene chloride, paraffin, and the like. Especially in the case of transfer, polypropylene ( PP), polyethylene (P
E) is preferred.

The moisture-proof layer 18e has a thickness of 0.2 to 2.0 mm.
Is appropriate. If it is less than 0.2 mm, the moisture resistance and moldability are poor, and if it is more than 2.0 mm, the shaft diameter becomes large and the usability is poor, and the transparency is poor. The thickness is more preferably 0.4 to 1.0 mm, further preferably 0.5 to 0.8 mm.

The following methods are suitable for forming the moisture-proof layer 18e. In the case of transfer, for example, a film on which a metal or inorganic layer is formed is attached in layers. In the case of printing, a gas barrier substrate and a metal or an inorganic substance are printed. In the case of coating, ethylene vinyl alcohol copolymer (EVO
H), vinylidene chloride, etc. are applied. Also, wax is applied. Wax is preferable because it is not so limited by the material of the other party to which it is applied (transfer or the like has a problem that it is easily peeled off depending on the material of the other party). Here, the wax means an organic substance that becomes a low-viscosity liquid when it is solidly heated at room temperature, and examples thereof include natural waxes such as animal and vegetable waxes, mineral waxes, and petroleum waxes extracted from petroleum (paraffin wax, microcrystalline wax). Wax, petrolatum), synthetic wax Fischer-Tropsch wax, polyethylene wax and the like. In the case of vapor deposition, a metal such as aluminum is vapor deposited and overcoated. Alternatively, an inorganic material such as silicon oxide is vapor-deposited or overcoated. Other configurations are basically similar to those of the first embodiment shown in FIG.

As in the above, the writing tip 10 is attached to the tip.
A tube body 14 made of a material having low gas permeability or gas impermeability, in which the ink 12 to be supplied to the writing chip 10 is housed and the rear end is closed.
And a pressurized gas enclosed in the tube body 14, which is a gas-pressurized writing instrument, wherein the moisture-proof layer 18e is transferred or printed, or applied or vapor-deposited on at least a part of the outer surface of the tube body. It can also be formed.
Embodiment 9 showing this embodiment is shown in FIG.
Also in this case, the moisture-proof layer 18e can be provided only in a portion in contact with the outside air. It can also be provided on the entire surface. Further, although it may be provided in one portion, in this case, it is preferable to provide it in the grip portion 32.

FIG. 8 more specifically shows the writing instrument of the first embodiment, in which the writing tip, the tube body and the accommodating cylinder are integrally attached to and detached from the shaft cylinder of the writing instrument which is the exterior member 22. It is a refill that can be installed.

[0067]

According to the present invention, it is possible to provide a gas pressure type writing instrument and a refill for a writing instrument which can prevent gas leakage with a simple structure having a small number of parts.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional explanatory view of a gas pressure type writing instrument applied to a first embodiment of the present invention.

FIG. 2 is a vertical half cross-sectional explanatory view for explaining the periphery of the joining member 20 of FIG.

FIG. 3 is a vertical cross-sectional explanatory view of a gas pressurizing writing instrument applied to Embodiment 2 of the present invention.

FIG. 4 is a vertical cross-sectional explanatory view of a gas pressurizing writing instrument applied to a third embodiment of the present invention.

FIG. 5 is a vertical cross-sectional explanatory view of a gas pressurizing writing instrument applied to Embodiment 4 of the present invention.

FIG. 6 is a vertical cross-sectional explanatory view of a gas pressure type writing instrument applied to Embodiment 5 of the present invention.

FIG. 7 is a vertical cross-sectional explanatory view of a gas pressure type writing instrument applied to Embodiment 6 of the present invention.

FIG. 8 is a vertical cross-sectional explanatory view of a gas pressure type writing instrument more specifically showing the writing instrument according to the first embodiment of the present invention.

FIG. 9 is a vertical cross-sectional view of a gas pressurizing writing instrument showing Embodiments 7, 8 and 9 of the present invention.

[Explanation of symbols]

10 Writing chips 10a tip 10b Tip contact part 10c step 10d reduced diameter part 10e Large diameter part 12 ink 14 tube body 14a tip 14b rear opening 16 spaces 18 Housing cylinder 18a moisture barrier 18c gas barrier layer 18d gas barrier layer 18e moisture barrier 20 Joining member 22 Exterior material 22a tip opening 24 chip holder 24a locking part 26 tail plug 27 Rear locking part 27a Housing cylinder rear locking part 27b Tip holder rear locking part 28 shaft cylinder 29 Locking protrusion 30 insertion hole 31 Airtight holding joint 32 Grip part 33 grip 34 Gap 35 Vent 36 Thin part

Claims (16)

[Claims] 1. A gas comprising a tube body having a writing tip at its tip and containing ink to be supplied to the writing tip inside and a closed rear end, and a pressurized gas sealed in the tube body. A pressure-type writing instrument, characterized in that a gas barrier layer exhibiting low gas permeability or gas impermeability is formed on at least a part of an inner surface or an outer surface of the tube body. 2. The gas pressure writing instrument according to claim 1, wherein the material of the gas barrier layer is ethylene vinyl alcohol copolymer (EVOH). 3. The tube body is made of polyethylene terephthalate (PET), nylon, polyethylene naphthalate (PEN), or polybutylene terephthalate (PBT), and the gas barrier layer is made of ethylene vinyl alcohol. The gas pressure writing instrument according to claim 1, wherein the writing instrument is a polymer (EVOH). 4. The gas-pressurized writing instrument according to claim 1, wherein at least a part of the tube body is made of a transparent or translucent resin, and the internal ink is visible. 5. A writing tip is provided at the tip of the tube body, in which ink to be supplied to the writing tip is stored, and a rear open tube body is provided, and a space communicating with the open portion at the rear side of the tube body is provided. And a housing cylinder with a closed rear end that encloses at least a part of the tube body, wherein the housing cylinder has a low gas permeability or gas impermeability on at least a part of its inner surface or outer surface. And a pressurized gas is enclosed in a space provided between the tube body and the accommodating cylinder body. 6. The tube body is housed in the housing cylinder by joining the housing cylinder and a writing tip so that the tube body does not come into contact with the outside air. Gas pressure type writing instrument. 7. The joint member for maintaining the airtightness of the space between the tube body and the containing cylinder body is provided between the tube body and the containing cylinder body. Gas pressure type writing instrument. 8. The tube body is enclosed in the accommodating cylinder body by providing a joining member for maintaining the airtightness of the space between the tube body and the accommodating cylinder body between the accommodating cylinder body and the writing tip. The gas-pressurized writing instrument according to claim 5, wherein the tube body is prevented from coming into contact with the outside air. 9. The gas additive according to claim 7, wherein a gas barrier layer exhibiting low gas permeability or gas impermeability is formed on at least a part of the inner surface or the outer surface of the joining member. Pressure writing instrument. 10. The gas-pressurized writing instrument according to claim 5, wherein the material of the gas barrier layer is ethylene vinyl alcohol copolymer (EVOH). 11. The material of the container is any one of polyethylene terephthalate (PET), nylon, polyethylene naphthalate (PEN), or polybutylene terephthalate (PBT), and the gas barrier layer is made of ethylene vinyl alcohol. The gas-pressurized writing instrument according to any one of claims 5 to 9, wherein the writing instrument is a copolymer (EVOH). 12. The gas pressurizing writing instrument according to claim 7, wherein the joining member is integrally formed with the housing cylinder. 13. The gas-pressurized writing instrument according to claim 5, wherein ink does not come into contact with the housing cylinder and / or the joining member. 14. The tube body and the accommodating cylinder body are at least partially made of transparent or translucent resin, and the internal ink is visible. The gas-pressurized writing instrument according to the item. 15. The volume of the space provided between the tube body and the containing cylinder body is 2 to 10 times the volume of the ink contained in the tube body in the initial state, and the ink is consumed immediately before the end of writing. The pressure in the space is 0.15
The gas pressurizing writing instrument according to any one of claims 5 to 14, wherein a gas is enclosed in the space so as to have a pressure of MPa to 0.6 MPa. 16. A refill for a writing instrument, characterized in that the writing tip, the tube body, and the accommodating tubular body according to any one of claims 5 to 15 are integrated into a refill that can be detachably mounted in a shaft tube of the writing instrument.