JPH0483695A - Writing instrument containing aqueous ink - Google Patents

Abstract

PURPOSE:To extremely simply obtain a positive and negative gas pressure change treating mechanism by opening the rear end of a cylinder, and forming a tail plug containing liquid of a water repelling member having air permeability in the rear end of the cylinder. CONSTITUTION:When a writing member 4 is disposed in an upward state, a water repelling member 6a having air permeability is sole, and hence the ventilation is free. A water repelling member 6b having air permeability of a tail plug 8 is blocked with aqueous ink (i) by a liquid plug state inside a cylinder 2, and a water repelling member 6c having air permeability is blocked with liquid 9. Accordingly, since the plug 8 is blocked externally from the interior of the cylinder 2, ventilation is impossible, but the cylinder 2 is externally ventilated from the exterior to the interior. If gas in the cylinder 2 is expanded due to an environmental change therearound, i.e., a temperature rise, an atmospheric pressure drop, since the member 6a having the air permeability is sole, the cylinder 2 is ventilated from the interior to the exterior, thereby holding the interior of the cylinder 2 in an atmospheric pressure state.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention is directed to a writing instrument that achieves a writing state by guiding water-based ink contained in a cylinder to the tip of a writing member attached to the front end of the cylinder. .

"Prior Art and Problems to be Solved by the Present Invention" Writing instruments have been widely known in the past, which have a structure in which water-based ink is accommodated in a cylinder and the ink is guided to the end of the writing brush using the capillary action of writing Bβ material. It is being For this type of writing instrument, it is essential to have a mechanism that can cope with changes in the positive and negative pressure of the air inside the cylinder during the process of continuing the writing state or under rapidly changing environments in a stationary state. , - A "pen core mechanism" consisting of comb grooves etc. that temporarily accumulates ink is employed in connection with the structure of the writing member.

In the pen core mechanism, when writing, outside air is introduced through the ventilation groove to maintain atmospheric pressure inside the cylinder, in response to negative pressure of air inside the cylinder, and when the air expands, positive pressure is maintained. The ink that oozes out under pressure is temporarily retained in the comb grooves, thereby preventing the ink from flowing out from the writing member.

However, this pen core mechanism is structurally complex due to its relationship with the writing member, and requires precision, making it difficult to handle.

Note that there are various other writing instruments that have a mechanism that deals with the positive and negative pressure states of the air inside the cylinder. For example, there is a method in which a pipe member for intake and exhaust is inserted into a cylinder to cope with the occurrence of positive and negative pressure phenomena, but this method lacks reliability in practical use.

"Means for Solving Problems" The present invention has been made in view of the state of the prior art, and includes a water-repellent portion that allows ventilation at the front end of a closed cylinder to which a writing member is attached. A means to solve the problem is to open the rear end of the cylinder and form a tail plug in the rear end of the cylinder that stores a breathable water-repellent liquid. It is said that

"Example" Hereinafter, the present invention will be described in detail with reference to the drawings.

A writing instrument 1 according to the present invention stores water-based ink 1 in an ink chamber 12 within a cylinder body 2, and is equipped with a writing member 4 attached to a front end portion 3 of the cylinder body. Ink 1 is guided to the brush end BB 4 a to achieve a writing state.

As shown in the drawing, the writing member 4 is composed of a tip ball portion 4a that caulks and holds the ball, and an ink guiding member 4b that guides the water-based ink 1 to the tip ball portion 4a, that is, to the writing hole. However, the present invention is not limited to this, and may be, for example, a felt-tip pen made of fiber bundle material.

A water-repellent portion 5 that allows ventilation is formed on the front end portion 3 of the cylinder. It is important that the water repellent member 6 is formed with air permeability to prevent leakage.

In the case illustrated in FIGS. 1 and 2, a ventilation hole 5a is bored at an appropriate location in the closed front end 3,
is shielded with a breathable water-repellent member 6 (6a), FIG. 1 shows the shield set in one part, and Figure 2 shows the shield set in multiple parts. It is.

Further, in FIG. 3, the entire front end portion 3 of the cylindrical body is formed of a water-repellent member 6 (6d) having air permeability.

As the breathable water-repellent member 6, those processed from fluororesin materials are widely known.For example, there are filter-shaped ones, fiber sheet-shaped ones, and plate-shaped ones. , FIGS. 1 and 2, the breathable water-repellent member 6 used is a fiber sheet-like material 6 (6
A) is easy to use, and a plate-shaped material 6 (6d) is suitable as a constituent material for the water-repellent portion 5 that allows ventilation as shown in FIG.

The rear end 7 of the cylindrical body 2 is open, and inside the rear end 7 there are two air-permeable water repellent members 6 (6b) arranged in two stages.
), 6 (6c), leaving an appropriate gap S between the liquid 9
A tail plug part 8 is formed that stores the. It is important that the structure of the tail plug part 8 is such that the water-repellent member 6 having air permeability stores the liquid 9.

As described above, the tail plug part 8 can be easily formed and has a structure that stores the liquid 9 between the breathable aqueous member 6 (6b) + 6 (6c), as illustrated. , can be said to be the most preferable specification since it is also excellent in terms of effectiveness, but it is of course not limited to this specification.

"Action" Hereinafter, the action of the present invention will be explained based on Examples.

First, regarding the water repellent member 6 having air permeability, as shown in FIG.
This will be explained using 1) and (2).

In the case of the breathable water-repellent member 6 alone shown in FIG. 4(1),
Ventilation is free. Further, FIG. 4(2) shows a case where liquid 9 is present on the water-repellent member 6 having air permeability.

As a natural phenomenon, gas moves from the bottom to the top of the liquid due to the difference in specific gravity. Therefore, if the liquid 9 exists on the air-permeable water-repellent member 6, ventilation from the bottom to the top is possible; Since liquid 6 is water repellent and does not pass through, liquid 9 acts as a liquid stopper, making ventilation impossible.

FIG. 1 (1) shows the writing member 4 in a downward position. The air-permeable water-repellent member 6a serves as a liquid stopper for the water-based ink 1 on the inside of the cylindrical body 2, and communicates with the outside air through the vent hole 5a on the outside of the cylindrical body 2. Therefore, in this part, ventilation from the outside of the cylinder 2 to the inside is possible, but the cylinder 2
Ventilation from the inside to the outside is impossible due to the presence of the water-based ink 1, and the flow is one-way from the outside to the inside of the cylindrical body 2.

In addition, in the tail plug part 8, there is an appropriate gap S between the breathable water-repellent members 6 (6b) + 6 (6c) arranged in two stages.
, and liquid 9 is stored. In addition, the water repellent member having air permeability is not limited to two stages; the existence of this gap S increases the volume when gas passes through the liquid 9 during ventilation, and increases the volume of the liquid 9 due to changes in the surrounding environment. This is to accommodate changes in volume. When the writing member 4 is in the downward state, this liquid 9 is absorbed by the water-repellent member 6 (6b) having breathability.
) side.

In this part, ventilation from the inside of the cylinder 2 to the outside passes through the water-repellent member 8 (6b) having air permeability, through the liquid 9, and through the water-repellent member 6 (6c) having air permeability. It is possible by doing this.

In addition, ventilation from the outside of the cylinder 2 to the inside passes through the water-repellent member 6 (6c) that has air permeability, but due to the presence of the liquid 9 on the water-repellent member 6 (6b) that has air permeability, the liquid stopper It is impossible because of the state. Therefore, since the tail plug part 8 is in a liquid plug state, the water-based ink 1 does not flow out from the writing member 4.

In a normal writing state, the inside of the cylinder 2 becomes a negative pressure state due to one volume of consumed water-based ink. In response to this negative pressure state, through the breathable water repellent member 6 (6a),
Ventilation is carried out from the outside of the cylinder 2 to the inside to maintain the inside of the cylinder 2 at atmospheric pressure. This allows for smooth writing.

The gas inside the cylinder 2 expands due to changes in the surrounding environment, ie, a rise in temperature and a fall in atmospheric pressure. As a result, the inside of the cylindrical body 2 is brought into a positive pressure state. As described above, the function of the tail plug part 8 is that gas corresponding to the expansion volume of the gas in the cylinder 2 is vented from the inside of the cylinder 2 to the outside, thereby maintaining the inside of the cylinder 2 at atmospheric pressure.

Conversely, the gas inside the cylindrical body 2 contracts due to a decrease in temperature and an increase in atmospheric pressure. As a result, the inside of the cylinder 2 becomes in a negative pressure state. The action at this time is to ventilate from the outside of the cylinder 2 to the inside through the aqueous member 6 (6a) having air permeability, and to maintain the inside of the cylinder 2 at atmospheric pressure. Water-based ink l will not flow out and air will not get mixed into the writing member 4.

FIG. 1(2) shows the writing member 4 in the upward position.

Since the water-repellent member 6 (6a) having air permeability is a single unit, ventilation is free. In addition, the water-repellent member 6 (6b) having air permeability of the tail plug part 8 has a water-based ink on the inside side of the cylinder body 2.
The water repellent member 6 (6c
) becomes liquid stopper state. Therefore, the tail plug part 8
Since it is a liquid stopper state from the inside of the cylinder X2 to the outside, ventilation is impossible, but ventilation from the outside of the cylinder X2 to the inside is possible. In other words, the tail plug part 8 does not allow the cylinder body 2 to ventilate.
It is a one-way street from outside to inside.

The gas inside the cylinder 2 expands due to changes in the surrounding environment, ie, a rise in temperature and a fall in atmospheric pressure. As a result, the inside of the cylindrical body 2 is brought into a positive pressure state. The action at this time is that since the water-repellent member 6 (6a) having air permeability is a single unit, it ventilates from the inside of the cylinder 2 to the outside, and maintains the inside of the cylinder 2 at atmospheric pressure.
On the other hand, as the temperature decreases and the atmospheric pressure increases, the gas inside the cylinder body 2 contracts. As a result, the inside of the cylinder 2 becomes in a negative pressure state.

The action at this time is that the water repellent member 6 (6a
) is a single unit, so ventilation is carried out from the outside of the cylinder 2 to the inside,
The inside of the cylinder 2 is maintained at atmospheric pressure. Due to these effects,
If the water-based ink 1 flows out from the writing member 4 or the writing member 4
No air is mixed in.

When the writing instrument 1 is placed horizontally, if there is only one breathable water-repellent member 6 (6a), depending on the horizontal position, it may be buried in the water-based ink, causing problems when under positive pressure. cause

For this reason, it is preferable to provide a plurality of locations and to have locations exposed from the water-based ink 1, that is, locations where the inside of the cylinder 2 and the outside communicate with each other.

In addition, in this horizontally placed state, in the 1 tail plug part 8, 2
Water repellent members 6 (6b), 6 with breathability arranged in stages
The liquid 9 between (6c) and the gas in the gap S become liquid 9 on the lower side and gas on the upper side, and the inside of the cylinder 2 and the outside communicate with each other.

Therefore, during writing, when the surrounding environment changes, the inside and outside of the cylinder 2 are separated from each other by the air permeable water-repellent members 6 (6a, 6b, 6c) of the front end 3 and the tail plug 8. ) through which ventilation is free.

Note that FIG. 5 illustrates a writing instrument 1 in which the writing member 4 is in an upward position, which is a so-called upside-down writing state.

When writing upside down, the water-based ink l is on the tail plug 8 side, so if one end 4' of the writing member 4 is made long enough to be buried in the water-based ink l on the tail plug 8 side, it is possible to write upside down. A writing instrument 1 is obtained.

When writing upside down, the interior of the cylinder 2 becomes under negative pressure due to one volume of the consumed water-based ink.

For this negative pressure state, a water repellent member 6 with breathability
Since (6a) is a single unit, ventilation is free, and the cylindrical body 2
Ventilation is carried out from the outside to the inside, keeping the inside of the cylinder 2 at atmospheric pressure.
This allows for smooth writing.

Note that (10) in the figure is a base portion 10 that covers the front end portion 3 of the cylindrical body, and is detachably attached to the cylindrical body 2. 10
A is a ventilation hole provided in the base portion 10. Further, reference numeral 11 denotes a lid body 11 having a ventilation hole 11a fitted into the open rear end portion 7 of the cylindrical body 2.

"Effects" Since the present invention has the above-mentioned configuration, a mechanism for dealing with changes in the positive and negative pressure of the gas inside the writing instrument cylinder during continuous writing can be obtained extremely easily, and a safe container containing water-based ink can be obtained. Moreover, a writing instrument with a simple structure can be easily obtained.

Further, according to the present invention, as mentioned above, a writing instrument that can be used to write upside down with the brush end facing upward can also be used.
It can be obtained very easily.

[Brief explanation of the drawing]

FIGS. 1 (1) and (2) are longitudinal cross-sectional views illustrating a writing instrument according to the present invention, with FIG. 1 (1) illustrating the writing instrument in a normal writing state; 2) describes what happens when it is not in a writing state. FIG. 2 is an explanatory diagram of a water-repellent portion that allows ventilation in the case 5; FIG.
FIG. 3 is a schematic explanatory diagram of an example in which it is formed on the entire surface of the front end of the cylindrical body. FIGS. 4(1) and 4(2) are explanatory diagrams of a water-repellent member with breathability, and FIG. 4(1) is a schematic explanatory diagram of the water-repellent member itself with breathability. Figure 4 (2
) is a schematic explanatory diagram of the relationship structure with liquid. FIG. 5 is a longitudinal sectional view illustrating a writing instrument in an upside-down writing state with the brush end facing upward. DESCRIPTION OF SYMBOLS 1...Writing instrument, 2...Cylinder, 3...Cylinder front end, 4...Writing member, 4...One end of writing member, 4a...Brush end, 4b... Ink guide member, 5...Water rupture point allowing ventilation, 5a...Vent hole at front end of cylinder, 6 (6a, 6b, 6c, 6d)--Water repellent member with breathability, 7 ... Rear end of cylinder body, 8 ... Tail plug part, 9 ... Liquid, 10 ... Mouth part, 10a ... Vent hole, 1
DESCRIPTION OF SYMBOLS 1... Lid body, 11a... Ventilation hole, 12... Ink chamber, l... Water-based ink, S... Gap. Figure 1 (1

Claims (1)

[Claims] A cylindrical body with a writing member attached thereto, in a writing instrument that stores water-based ink in the cylindrical body and guides ink from the writing member attached to the front end of the cylindrical body with a closed end face to the brush end of the writing member using capillary action. A water-repellent part that allows ventilation is formed at the front end, and the rear end of the cylinder is opened, and a tail plug part that stores liquid with a water-repellent material that has air permeability is placed inside the rear end of the cylinder. A writing instrument containing water-based ink, characterized by the fact that: