JPS6223785Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is a thixotropic ink that is in a gel state when not in writing, but reversibly converts into a sol state when writing and is derived from the pen tip. This invention relates to improvements to writing implements with built-in components.

(Prior art) Conventionally, pen nibs made of felt, pen nibs made of fiber bundles thermoset with synthetic resin, so-called plastic pen nibs with an ink guide gap formed in the axial direction of a synthetic resin tube, ballpoint pen nibs, etc. Directly or indirectly through a so-called ink guide core for adjusting the ink flow rate, the pen comes into contact with a bottomed ink cylinder containing ink or an ink cylinder made of a fiber bundle impregnated with ink, and the ink is drawn to the pen tip by capillary action. Writing implements such as marking pens and water-based ballpoint pens that are configured to draw out more information are used.

The inks used in these writing instruments can be roughly divided into two types: water-based and oil-based, and the former has a viscosity of 2.5~
7 CPS., and the latter uses low viscosity ink of about 7 to 20 CPS.

Therefore, if the pen tip is left facing upward for a long time, a so-called ink drop phenomenon occurs, resulting in blurring.

This phenomenon is particularly noticeable in pens using plastic nibs, and water-based ballpoint pens may run out of ink and become unable to write. In addition, an ink-free type ink cylinder requires a complicated ink delivery mechanism and is expensive. An ink cylinder using a fiber bundle requires a fiber bundle, and the amount of ink that can be contained is small, and the ink is retained between the fibers by capillary action, making it impossible to use the entire amount of ink. As a result,
The writing distance is short, and even if the ink cylinder is transparent, the remaining amount of ink cannot be visually confirmed. Furthermore, it has the disadvantage that an ink drop phenomenon occurs and ink may leak due to a shock such as dropping.

In order to overcome these drawbacks, a water-based ink having thixotropic properties and a writing instrument using the ink have been disclosed (Japanese Patent Publication No. 55
-18474 Publication).

(Problems to be Solved by the Invention) The writing instrument disclosed in the present invention can overcome the drawbacks of the conventional writing instruments mentioned above, and can accommodate a larger amount of ink in the ink cylinder. If the diameter of the ink cylinder is increased, the amount of built-in ink per cross-sectional area will inevitably increase, so when the pen tip is pointing downward, the pressure applied to the pen will be large, so it will become a sol and will flow more than the pen tip. This has the disadvantage of causing leakage.

This phenomenon is particularly noticeable when the ink is subjected to a shock such as a fall, since a large shearing force is applied and the ink retention force is rapidly reduced.

Furthermore, when the pen tip is facing upward, there is a problem that the ink may leak from the rear end of the cylinder.

That is, a writing instrument containing an ink having thixotropic properties as disclosed in the present invention, for example, as shown in FIG. A pen nib 1 having a gap that can be drawn out, a pen nib holder 2 in which the pen nib 1 is inserted and held in a central hole 3, and a transparent transparent material made of synthetic resin, etc., with an opening fitted in the large diameter part 4 of the holder 2. It is composed of a shaft cylinder 6, and an ink cylinder 7 whose one end is tightly fitted into the small diameter part 5 of the nib holder 2, communicating with the end of the nib 1, and containing ink 8 having thixotropic properties. The cylinder 7 is made of a transparent synthetic resin such as polypropylene or vinyl chloride resin, and usually has an inner diameter of 2.5 to 5.0 mm and a length of about 80 to 120 mm.

However, if the inner diameter exceeds 5.0 mm, the above-mentioned disadvantages arise.

The present invention aims to solve this problem and provide a writing instrument that can contain a larger amount of thixotropic ink.

(Structure of the invention) As shown in FIG. 1, the writing instrument of the invention includes an ink cylinder 17, a small diameter cylinder 15 with a pen tip 11 inserted into one end and an open end, and a large diameter cylinder 16 with a bottom. It is formed into a double cylinder shape with concentrically inserted outer cylinders, and ink is contained in the small diameter cylinder 15 and in the gap between the large diameter cylinders 16 communicating with the small diameter cylinder 15.

(Function) With the above configuration, the present invention has a large diameter ink cylinder 17.
Since the inside is divided in a continuous manner, the ink retention force within the ink cylinder 117 is prevented from decreasing, and a large amount of ink can be stored without causing the bottle to leak due to a shock such as dropping.

(Example) In FIG. 2, reference numeral 11 denotes a pen nib connected to the tip of the holder 12.

The pen nib 11 is configured as a ballpoint pen nib including a ball 122 rotatably held in a ball holding hole 121, an ink guiding hole 123 communicating with the holding hole 121, and a center hole 124 communicating with the hole 123. has been done.

One end of a small-diameter cylinder 15 having an inner diameter of about 1 to 3 mm and open at both ends is tightly fitted into the central large-diameter hole 125 of the holder 12 and communicated with the pen tip 11 . A large-diameter cylinder 16 with an inner diameter of about 5 to 15 mm and a bottom, which also serves as a shaft cylinder, is concentrically inserted into the small-diameter cylinder 15, and its open end 161 is fitted and fixed into the fitting part 126 of the holder 12. An ink cylinder 17 is constructed.

Reference numeral 127 is a vent hole that communicates the ink cylinder 17 with the outside air.

There is a gap 2 between the inside of the small diameter cylinder 5 constituting the ink cylinder 17 and the large diameter cylinder 16 communicating with the small diameter cylinder 15.
0 has built-in ink 18 having thixotropic properties, and the ink 18 enters the central large diameter hole 12.
4. The ink is guided through the ink guiding hole 123 to the gap between the holding hole 121 and the ball 122.

The ink 18 is in a gel state (solid state) in a stationary state, that is, in a non-writing state, but becomes a sol state (a fluid liquid) when writing, and is drawn out from the pen tip 11.

If the ink 18 is a water-based ink, for example, C.I.Assisted 87 8.0 copies (Hodogaya Chemical Eosin) Ethylene glycol 30.0 parts Agar 0.2 parts Water 61.8 parts If it is oil-based ink C.I. Solvent Blue 70 5.0 parts (BASF Neozapon Blue FLE) Ethyl cellosolve 84.0 parts Dibenzylidene sorbitol 1.0 part Polyvinyl butyral resin 10.0 parts An ink obtained by mixing and dissolving each of them is used.

In this example, the strength of the gel state can be adjusted by increasing or decreasing the amounts of agar and dibenzylidene sorbitol.

Reference numeral 19 denotes a sealant made of silicone grease or the like, which is sealed as necessary.

The sealing material 19 has one end in close contact with the ink 18 and moves as the ink 18 is consumed.
Prevents backflow and drying.

Therefore, when writing, when the pen tip 11 contacts and writes on a writing surface such as a paper surface, the holding portion 121 and the ball 1
The ink 18 guided into the gap between 22 is affected by writing pressure,
The mechanical stimulation caused by the rolling of the ball 122 promotes the conversion to a sol state, and the pen tip 11
Stimulation by capillary attraction from the ball 122 to the capillary tubes on the writing surface transforms the writing surface into a sol state and allows it to flow. In addition, the ball holding portion 121 is brought into a reduced pressure state, and the ink 18 is forcibly drawn out by suction, allowing for good writing.

Then, when writing is stopped, the ink 18 is converted into a gel state, and effects unique to a writing instrument containing thixotropic ink are produced.

In particular, in the present invention, the large diameter ink cylinder 17
The inside is configured to be divided into a continuous shape, and
Ball 122 has h.ρ. Since only the pressure of g. (h: distance from the ball to the ink surface, ρ: specific gravity of the ink, g: gravitational acceleration) is applied, there is no risk of bottle leakage even though it contains a large amount of ink. do not have.

The same applies when a shock is applied, such as when the device is dropped.

In the present invention, instead of the ballpoint pen nib 11, a marking pen nib such as a so-called plastic nib in which an ink guide gap is formed in the axial direction of a synthetic resin tube may also be used.

(Effects of the Invention) As described above, the present invention does not cause any leakage and can contain a larger amount of thixotropic ink, so it can be used for a longer period of time.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of a conventional writing instrument containing ink having thixotropic properties. 11... Pen tip, 17... Ink cylinder, 15...
Small diameter cylinder, 16... Large diameter cylinder, 18... Ink having thixotropic properties.

Claims (1)

[Scope of utility model registration request] A writing instrument in which the pen tip is directly or indirectly connected to an ink cylinder, and the ink cylinder contains ink having thixotropic properties that is in a gel state when not writing but reversibly changes to a sol state when writing. , the ink cylinder is constituted by a large diameter cylinder with a bottom being concentrically inserted into a small diameter cylinder in which a pen tip is inserted into one end and the other end is open, and the ink cylinder is configured such that a large diameter cylinder with a bottom is fitted concentrically to a small diameter cylinder in which a pen tip is inserted into one end and the other end is open; A writing instrument containing ink having thixotropic properties, characterized in that ink is contained in a gap between communicating large-diameter cylinders.