JPH11309977A - Writing utensil and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress leakage of an ink to the outside of a writing utensil as much as possible even under a state wherein the ink exists in an air passage by some unexpected situation by a method wherein for a temporary ink reservoir member, an ink-philic surface is formed, and in a barrel internal wall part which becomes the air passage, an ink-phobic surface is formed. SOLUTION: On the opening side in a barrel cylinder 1, a temporary ink reservoir member 2 is attached, and the bottom side is made an ink tank 3. In a central hole 2a, a nib part comprising a joint part 6a and a ball-point pen tip 6b, and an ink joint core 5 made of a fiber bundle are inserted. The temporary ink reservoir member 2 has a plurality of comb tooth-form parts 2c on the outside, and spaces between respective comb tooth-form parts 2c become a temporary ink reservoir part 2b having a capillary force. On the barrel, cylinder internal wall 1b and the surface of the press-bonding face of a circumferential press-bonding part 7, an ink-phobic treatment is applied, and on the temporary ink reservoir part 2b, an ink-philic treatment is applied. By this method, an ink which has come out to the air passage by an impact or an excessive flow-out, is prevented from reaching an air hole 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink tank which is provided with a temporary ink reservoir for controlling the exchange of ink and air into an ink tank in a barrel between a pen tip and an ink tank. The present invention relates to a writing implement which supplies air into an ink tank from an air passage which is a gap between a shaft inner wall portion and a temporary ink reservoir member in order to suppress a pressure reduction in the inside.

[0002]

2. Description of the Related Art Conventionally, as a so-called raw ink type writing implement for storing ink in an ink tank in a free state, a temporary ink reservoir member for controlling supply of ink used for writing to a pen tip is provided by an ink tank and a pen tip. Is known between the two.

[0003] A temporary ink reservoir member is located in an air passage for supplying air into the ink tank, and communicates with both the air passage and the inside of the ink tank. An ink / air boundary is formed by the ink retaining ability of the temporary ink reservoir member by the capillary force, and when the internal pressure in the ink tank becomes relatively high, the ink is stored in the temporary ink reservoir section. If the internal pressure in the ink tank is reduced and the ink is ejected from the tank by writing and the internal pressure in the ink tank is reduced, the ink in the temporary ink reservoir is returned to the ink tank and air is also stored in the ink tank. The supply of air can be controlled according to the state in the ink tank, such as by increasing the internal pressure in the ink tank by supplying the air.

[0004]

As mentioned above, the temporary ink reservoir is also in communication with an air passage for ink / air exchange, which means that the ink tank is indirectly in communication with the air passage. Will be. That is, the ink can move into the air passage, and the ink may leak out of the writing implement through the air passage. For example, if the atmospheric pressure drops suddenly or if the device is placed in a high-temperature environment, there is a danger that ink that cannot be suppressed by the ink holding capacity of the temporary ink reservoir member will leak out, and during transportation. In addition, there is a danger that the ink received by the writing implement itself scatters into the air passage and flows out of the writing implement.

[0005]

That is, according to the present invention, a temporary ink reservoir for controlling the exchange of ink and air into an ink tank is provided in a barrel between a pen tip and an ink tank. In a writing instrument for supplying air into an ink tank from an air passage which is a gap between a shaft inner wall portion and a temporary ink reservoir member in order to suppress pressure reduction in the ink tank due to consumption, the temporary ink reservoir member The gist of the present invention is to provide a writing implement having an ink-repellent surface and an ink-repellent surface formed on an inner wall of a shaft forming the air passage.

[0006]

In a writing instrument having a temporary ink reservoir, a gap formed between the temporary ink reservoir and the inner wall of the shaft cylinder is used as an air passage. The inner wall of the barrel and the portion of the temporary ink reservoir member which is closest to the ink tank, which constitutes the wall surface of the air passage; A portion of the temporary ink reservoir member that presses against the inner wall of the shaft cylinder of the temporary ink reservoir member, and an annular elastic body interposed between the temporary ink reservoir member and the inner wall of the shaft cylinder, and ink repellent on the wall surface of portions other than the temporary ink reservoir member The temporary ink fountain member can be used for the temporary ink fountain in the temporary ink fountain even if ink is present in the air passage due to some unexpected situation. In which as much as it is possible to suppress the induction to leaking is ink out of the writing instrument.

[0007] Further, the temporary ink reservoir member is in contact with the inner wall of the shaft cylinder, which is a boundary portion pressed against the inner wall of the shaft cylinder, or the surface of the annular elastic body interposed between the temporary ink reservoir member and the inner wall of the shaft cylinder. An ink-repellent surface treatment agent is easily applied to the inner wall of the barrel by applying an ink-repellent surface treatment agent in advance and moving the temporary ink reservoir member to a predetermined position while pressing the portion against the inner wall of the barrel. The ink repellent surface treatment agent can be applied to the portion other than the temporary ink reservoir member of the portion forming the air passage by transferring the ink, and substantially all the necessary portions can be obtained by one surface treatment operation. Can be subjected to an ink-repellent surface treatment.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 1 shows a writing instrument of the present invention, which is an example of what is called a refill on the premise that it is housed in an exterior body (not shown). A temporary ink reservoir 2 is provided on the opening side of the shaft cylinder 1 formed in the bottomed cylinder.
And the bottom side is an ink tank 3 for storing ink in a free state. The temporary ink reservoir 2 has a pen tip holder 4 integrally provided at the front thereof, and penetrates both to penetrate the pen tip 6 into a center hole 2a leading to the pen tip. An ink relay core 5 made of a fiber bundle to be supplied is inserted. The pen tip 6 is the joint 6
a and a ballpoint pen tip 6b,
Has reached the inside of the ballpoint pen tip 6b via the inside of the joint 6a.

The temporary ink reservoir 2 has a plurality of comb-like portions 2c on the outer side, and the space between the comb-like portions 2c is a temporary ink reservoir 2b having a capillary force. . The center hole 2a through which the ink relay core 5 is inserted and the temporary ink reservoir 2b communicate with each other by a slit 2d. When pressure is relatively applied to the ink tank 3 due to a temperature change, a pressure change, or the like, excess ink pushed out by the pressure is not supplied to the pen tip portion 6 via the ink relay core 5 but temporarily passes through the slit 2d. The ink is temporarily stored in the ink reservoir 2b. At the rear end of the temporary ink reservoir member 2, the temporary ink reservoir portion 2 b
A circumferential press-contact portion 7 is integrally disposed as a boundary portion that partitions the ink tank 3 in a state where the ink can be freely moved and a portion where the ink is controlled by the ink relay core 5. When the ink in the ink tank 3 is consumed from the pen tip portion 6 through the ink relay core 5 by writing, the pressure in the ink tank is reduced, so that the temporary ink reservoir member 2 communicating with the outside through the air hole 8 is formed. 1c between the shaft cylinder 1
Is taken into the ink tank.

Here, Florad FC-905 (fluorine coating agent manufactured by Sumitomo 3M Ltd.) is applied to the surface of the pressure contact surface of the shaft cylinder inner wall 1b and the circumferential pressure contact portion 7 with the shaft cylinder inner wall 1b by toluene as an ink repellent treatment. And then dried. As an ink-repellent treatment,
Other examples include toluene, xylene, dimethylsiloxane polymer and perfluoroacrylate resin.
An ink repellent treatment can be performed by applying an appropriate solvent diluted with an organic solvent such as acetone, methanol, ethanol, methyl ethyl ketone or the like or water to the corresponding portion. On the other hand, the temporary ink reservoir 2b is provided with a parent ink obtained by immersing Polysol S-5 (polyvinyl acetate emulsion manufactured by Showa Polymer Co., Ltd.) in a 50-fold dilution with water and then drying. Processing has been applied. In addition to the ink-affinity treatment, the ink-affinity treatment can be performed by attaching a resin having a hydrophilic group in its molecule to the surface. Examples of such a hydrophilic group include a hydroxyl group, an amino group, a carboxyl group, and a carbonyl group. Specific examples of the resin include a polyvinyl alcohol resin, an ethylene vinyl acetate copolymer, a polyamide resin, and an ethylene vinyl alcohol copolymer. It is. Further, when acrylonitrile butadiene styrene resin is used for the temporary ink reservoir 2b, a material which is etched with a chromic acid-based etching solution may be used. In this way, even if the ink accumulated in the temporary ink reservoir 2b enters the air passage due to impact or excessive outflow, the ink is positively guided to the temporary ink reservoir 2b and the air holes are formed. Never reach 8.

FIG. 2 shows another example. The annular pressure contact portion 7 at the rear end of the temporary ink reservoir member 2 in the above-described example is replaced with an annular elastic body 17 as another member. The annular elastic body 17 is fitted to the rear end of the temporary ink reservoir 2, and the ink tank 39 and the temporary ink reservoir 2b
And maintain liquid tightness. Also in this case, an ink-repellent treatment is applied to the surface of the annular elastic body 17 pressed against the inner wall 1b of the shaft cylinder. The annular elastic body 17 has a cylindrical shape, and is made of a rubber material such as silicone rubber, butyl rubber, and isoprene rubber. By using such an elastic body, it is possible to use a material having a dimensional allowance for pressing against the inner wall 1b of the shaft cylinder as compared with a case made of a synthetic resin, which can be more reliable.

FIG. 3 shows an example of an assembling process according to the present invention. First, the pen tip 6 is attached to the pen tip holder 4, and the ink relay core 5 is moved from the rear end of the temporary ink reservoir 1 to a predetermined position. The pen tip portion 6, the temporary ink reservoir member 1, the ink relay core 5, the annular elastic member 17 are inserted and fixed, and the annular elastic member 17 is further fitted to the rear end of the temporary ink reservoir member 1.
Create an assembly consisting of Here, the surface treatment agent having ink repellency as described above is applied to the surface of the annular elastic body 17. Next, the writing instrument shown in FIG. 2 is obtained by inserting the assembly from the open end of the barrel 1 in which the ink tank 3 is filled with a predetermined amount of the ink 9 and moving it to a predetermined position. At this time, the outer diameter of the annular elastic body 17 is
By making the diameter slightly larger than the inner diameter of b, the ink-repellent surface treatment agent attached to the surface of the annular elastic body 17 is transferred to the inner wall 1b of the shaft cylinder. An ink-repellent surface treating agent can be applied to portions other than the temporary ink reservoir member 2 among the portions forming the air passage, that is, to the inner surface of the shaft cylinder inner wall 1b and the surface of the annular elastic body 17.

In addition to the above, various modifications can be made without departing from the gist of the present invention. By way of example, in the above-described example, the ball-point pen inner lining having a metal shaft and used by being housed in the outer body is illustrated, but a so-called main body that is used alone without being housed in the outer body. It may be a disposable writing instrument, or the shaft may be an extruded product of a synthetic resin. In addition to the ballpoint pen, the pen tip may be a fiber tip with a fiber bundle, a synthetic resin pen tip having a communication hole, or a small tube-type writing instrument including a small tube and a needle sliding in the small tube. Can also.

[0014]

As described above, the present invention relates to a writing implement capable of minimizing the leakage of ink to the outside of the writing implement.
It is another object of the present invention to provide a method for manufacturing a writing instrument that can easily obtain such a writing instrument.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example.

FIG. 2 is a cross-sectional view showing another example.

FIG. 3 is a cross-sectional view illustrating an example of a manufacturing method.

[Explanation of symbols]

 Reference Signs List 1 shaft cylinder 1a shaft inner wall 1b shaft cylinder inner wall 1c gap 2 temporary ink reservoir 2a center hole 2b temporary ink reservoir 2c comb tooth 2d slit 3 ink tank 4 pen tip holder 5 ink relay core 6 pen Tip 6a Joint 6b Ballpoint pen tip 7 Circular pressure contact 8 Air hole 9 Ink 17 Ring elastic body

Claims (4)

[Claims] 1. A temporary ink reservoir member for controlling exchange of ink and air into an ink tank is disposed in a shaft cylinder between a pen tip and an ink tank to suppress pressure reduction in the ink tank due to ink consumption. A writing instrument that supplies air into the ink tank through an air passage that is a gap between the shaft inner wall portion and the temporary ink reservoir member, wherein the temporary ink reservoir member has an ink-philic surface. A writing instrument, wherein an ink-repellent surface is formed on an inner wall of a shaft forming the air passage. 2. An inner wall portion of the shaft constituting the air passage is divided into an inner wall of a shaft cylinder, an ink tank which presses against the inner wall of the shaft tube to store ink in a free state, and an ink control portion which controls a flow of ink. 2. The writing implement according to claim 1, wherein the writing implement comprises a boundary portion. 3. The writing implement according to claim 2, wherein a boundary portion that is in pressure contact with the inner wall of the barrel is an annular elastic body. 4. An ink-repellent surface treatment agent is previously applied to a surface of a boundary portion that is in pressure contact with the inner wall of the barrel, and the boundary portion is moved to a predetermined position while being pressed against the inner wall of the barrel, and is repelled to the inner wall of the barrel. An ink-repellent surface treating agent is applied to the inner wall of the shaft by transferring an ink-based surface treating agent.
The method for producing a writing instrument according to item 1.