JP3538722B2 - Water-based ink composition for ballpoint pen and ballpoint pen using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ink composition for an aqueous ballpoint pen and a ballpoint pen using the same. More specifically, the present invention relates to a water-soluble ink composition for ballpoint pens having a smooth writing feeling and satisfying writing performance and storage performance, and a ballpoint pen using the same.

[0002]

2. Description of the Related Art Conventionally, ink for ballpoint pens has a viscosity of 10,000 to 20,000 m. Pa. s oil-based ballpoint pen ink composed of an oil-based solvent system having a viscosity of about 10 m. Pa. s
A low-viscosity water-based ballpoint pen ink composed of an aqueous medium has been widely used. The oil-based ballpoint pen ink has the advantage of being put into practical use by being filled into a relatively simple ballpoint pen mechanism, but has a heavy writing feel depending on the high viscosity of the ink itself, and has a high viscosity ink in a thin ink film state. The writing mechanism that transfers the image from the ball to the writing surface tends to cause defects such as a blur phenomenon, a so-called ink bottling phenomenon in which ink accumulates in the pen tip, and a bleeding phenomenon of the handwriting when writing in an environment where the outside temperature is high. On the other hand, a water-based ball-point pen using the low-viscosity water-based ball-point pen ink has an advantage that a thick writing density can be obtained with a light writing pressure, but an ink outflow control unit or the like for appropriately discharging the low-viscosity ink is provided. This necessitates a complicated structure composed of many parts, and also tends to cause a bleeding phenomenon during writing depending on the low viscosity of the ink.

In view of the above situation, in recent years, thixotropically imparted aqueous medium inks, so-called shear-thinning aqueous ballpoint pen inks, have been developed and put to practical use.
This type of ink has a high viscosity at the time of standing where no shear stress is applied, is stably held in a ball-point pen mechanism, and at the time of writing, the ball has a high shear force due to a high-speed rotating ball. Only the ink in the vicinity has a low viscosity, and as a result, the ink smoothly passes through the gap between the ball and the ball accommodating portion by the capillary force, and the ink is transferred to the paper surface. Since the ink transferred to the paper surface or the like is released from the shearing force, it becomes a high-viscosity state again, and does not cause the handwriting bleeding phenomenon which is a drawback of the conventional non-shear-thinning aqueous ballpoint pen.

Several proposals regarding the above-mentioned shear-thinning aqueous ballpoint pen ink have been disclosed. For example, those using water-dispersible gums, resins, polysaccharides and the like (for example,
U.S. Pat. No. 4,671,691, Japanese Patent Publication No. 64-867
No. 3). Incidentally, water-dispersible gums, resins and thickening polysaccharides disclosed in the above-mentioned publications and the like are capable of depolymerizing by microorganisms, decomposing by photochemical oxidation,
Due to the breaking action of the molecular chain due to the strong shearing force, there is a tendency for deterioration or deterioration, and it cannot be said that the shear thinning effect is stably and continuously satisfied.

Further, an organic polymer compound such as a crosslinked acrylic resin is used as a shear-thinning agent (Japanese Patent Application Laid-Open No.
Japanese Patent Application Laid-Open No. 7-49678) is disclosed. However, even if the crosslinkable acrylic resin exhibits a certain degree of shear thinning in a high-viscosity state, the effect of applying the water-based ballpoint pen to a writing mechanism can be reduced. It is not necessarily effective. That is, the shear-thinning effect is insufficient, and the balance between the low-viscosity property appropriate for writing caused by the shearing force at the time of writing and the high-viscosity property required for storage stability at the time of non-writing is not always satisfied. Not.

Attempts to use an inorganic compound such as inorganic fine particles as a shear-thinning agent (JP-A-6-256699)
However, even if fine particles such as anhydrous silicic acid fine particles exhibit water-absorbing and shear-thinning properties, they are largely dependent on the action of the cohesive force between the fine particles. Therefore, when this type of ink is applied as a ballpoint pen ink, it is considerably difficult for the three-dimensional structure of the aggregated particles to pass stably through the narrow gap between the ball and the ball house in a homogeneous state. Prone to cut. Also, swelling clays such as hydrophilic synthetic smectite are dispersed in finer particles as they are substantially closer to the dissolved state,
Even when good shear thinning is initially provided, water separates and drains from the gel body over time, ie, "syneresis".
This tends to cause a phenomenon, and has a drawback of causing local separation of the ink and cutting of the ink column in the ballpoint pen mechanism. On the other hand, as a prior art, an attempt has been disclosed in which an ethylene oxide adduct of a fatty acid amide is blended in a small amount of several percent or less into an aqueous ballpoint pen, but the ball is smoothly rotated as a lubricant in a low-viscosity dye-based ink. It is intended to fulfill the function of causing shear thinning and is not intended for shear thinning.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned disadvantages of the conventional ink for ballpoint pens, has a smooth writing feel, and has a shear-thinning aqueous ink composition for ballpoint pens that satisfies writing performance and storage performance. And a ballpoint pen using the same.

[0008]

Means for Solving the Problems The present inventors have intensively studied an ink for an aqueous ballpoint pen for solving the above-mentioned conventional problems, and have found that a specific fatty acid amide derivative exhibits excellent shear thinning. And found that the combination with a specific water-based ink vehicle more effectively exhibited the shear thinning effect and satisfied various performances as a ballpoint pen, thereby completing the present invention. . That is, the present invention provides a colorant, water, a water-soluble polar solvent, and a fatty acid amide derivative 6 represented by the following general formula (1) which exhibits a shear thinning function as essential components .
30% by weight as a shear thinning agent ,
The fatty acid amide derivative is kept at least partially dispersed.
To achieve and maintain the shear thinning function.
Be Te is required for the aqueous ball point ink composition according to claim. General formula (1)

Embedded image Here, R represents a straight chain or a side chain alkyl group having 13 to 21 carbon atoms or an unsaturated alkyl group, m is 0 to 10, n is 1
10 to 10. Furthermore, prior Symbol fatty acid amide derivatives, a phase in the dispersed state in the 0.5μm or less particulate in the ink, and a phase in substantially dissolved molecular association state is in the mixed state, the shear thinning It must be configured to express. Further, the fatty acid amide derivative contains a fatty acid amide derivative represented by the following general formula (2). General formula (2)

Embedded image Here, R represents a linear or side chain alkyl group having 13 to 21 carbon atoms and an unsaturated alkyl group, and n represents 1 to 5. Furthermore, prior Symbol aqueous ball point ink composition, the shear thinning index is characterized in that 0.1 to 0.6. Further, the aqueous ball-point pen ink composition comprises a colorant 1 to
It contains 35% by weight, 6 to 30% by weight of a fatty acid amide derivative exhibiting a shear thinning function, and 3 to 30% by weight of a water-soluble polar solvent, and the balance is water and an additive for adjustment.
160m. Pa. s (value at a rotational speed of 100 rpm in an EM-type rotational viscometer) and satisfies a shear thinning index of 0.1 to 0.6. Further, the fatty acid amide derivative is composed of a fatty acid having 14 to 22 carbon atoms and being liquid at 20 ° C., and one or more of the fatty acid amide derivatives are mixed in the ink. Characterized in that it accounts for at least 50% by weight or more of the amount. Furthermore, the present invention is characterized in that the coloring material is an aqueous ballpoint pen ink composition comprising a pigment. Furthermore, the colorant is a reversible thermochromic microcapsule pigment, an aqueous ballpoint pen ink exhibiting reversible thermochromic properties, furthermore, a reversible thermochromic microcapsule pigment is an electron donating organic compound, A pigment comprising a homogeneous film having an electron accepting compound and a reaction medium for controlling the discoloration temperature as essential components coated with a wall film, and having a particle distribution of 95% by volume or more in a range of 0.5 μm to 20 μm. Further, the reversible thermochromic microcapsule pigment is a pigment comprising a wall film formed by an interfacial polymerization or interfacial polycondensation method having a depression on at least a part of the outer surface. 0.5 μm to 20
3 to 30% by weight (solid content) of a reversible thermochromic microcapsule pigment occupying 95% by volume or more in the range of μ, 6 to 30% by weight of the fatty acid amide derivative exhibiting a shear thinning function, and 3 to 3% of a water-soluble polar solvent. 30% by weight, the balance consisting of water and conditioning additives, having a viscosity of 30-160 m. Pa.
s (value at a rotational speed of 100 rpm in an EM-type rotational viscometer), a shear thinning index in a range of 0.2 to 0.5, and a tip which holds a ball rotatably. In a ball-point pen configured to be able to write out by drawing out the ink stored in the ink storage unit, a colorant, water, a water-soluble polar solvent, and a shear thinning function are expressed as essential components in the ink storage unit. A ballpoint pen characterized in that a shear-thinning aqueous ballpoint pen ink containing a fatty acid amide derivative is stored in a direct liquid state, and furthermore, the ink storage section is formed of a pipe, and the ink composition in the storage state is It is required that an ink follower is disposed at the rear end.

As described above, the present invention applies a specific fatty acid amide derivative exhibiting a shear thinning function, and makes a compound selected from the above derivatives effectively function in combination with a specific aqueous vehicle, thereby effecting a shear thinning effect. The first requirement is a ballpoint pen ink that effectively expresses the above.

[0010] While the conventionally disclosed shear-thinning agent is a polymer compound, a resin, a gum or inorganic fine particles as described above, in the present invention, a low-molecular-weight organic compound is used. Have been found to satisfy an effective shear thinning function. Fatty acid amide compounds are roughly classified into four types according to their production methods. First, fatty acid monoethanolamide, second, 1: 1 fatty acid diethanolamide obtained by reacting at a ratio of 1 mole of fatty acid to 1 mole of diethanolamine, and third, at a ratio of 1 mole of fatty acid to 2 mole of diethanolamine. The reaction is carried out in the presence of an excess of diethanolamine to prepare a 1: 2 type fatty acid diethanolamide, and fourthly, a polyoxyethylene fatty acid amide for adding ethylene oxide to the fatty acid amide. When the same fatty acid is used, 1: 2 type fatty acid diethanolamide has higher hydrophilicity than 1: 1 type fatty acid diethanolamide. In the fourth type polyoxyethylene fatty acid amide, the hydrophilicity can be increased together with the number of added ethylene oxide. Therefore, the selection of the fatty acid amide derivative exhibiting the shear thinning function of the present invention is performed by selecting the fatty acid chain length, the fatty acid linear and side chains, the lipophilic component due to the fatty acid saturation / unsaturation and the like, and the terminal hydroxyl group. In addition, each fatty acid amide derivative can be selected in consideration of all the hydrophilic elements due to addition of ethylene oxide. The fatty acid amide derivative set to exhibit the shear thinning function is characterized in that at least a part thereof is dispersed in the form of fine particles in an aqueous medium. In general, fatty acid amide derivatives are known for use as surfactants, pigment dispersants, emulsion stabilizers, etc., but fatty acid amide derivatives are applied to the field of aqueous ballpoint pen inks for the purpose of imparting shear thinning. Attempts have not been disclosed. Conventionally, an application example of this kind of fatty acid amide derivative to a ballpoint pen is simply applied as a lubricant for a ballpoint pen ink, that is, to reduce wear of the ball and the ball seat and maintain a smooth writing feeling. Was only known.

In the course of studying a shear-thinning agent using a relatively low-molecular compound, the present inventors have noticed that some of aqueous solutions of various surfactants exhibit shear-thinning. And started the study. However, some surfactants have been found to have shear thinning at a certain temperature, but are difficult to stably respond to a temperature change in a practical temperature range of a ballpoint pen, for example, 0 ° C to 60 ° C.

The fatty acid amide derivative used in the present invention for imparting shear thinning viscosity to the ink retains stable viscosity and shear thinning viscosity not only in a normal temperature range but also in a temperature range from 80 ° C. to 100 ° C. The present inventors have found that they have the excellent property of being able to do so. The present inventors have also found that this stable shear thinning can be obtained by incorporating a fatty acid amide derivative in an amount of 6 to 30% by weight in the ink. In order for a low molecular compound to exhibit stable shear thinning properties, interaction between low molecular compound molecules in an aqueous medium is necessary. The lipophilicity of the alkyl chain of the fatty acid, the hydrophilicity of the diethanolamide group or polyoxyethylene group, the hydrophilicity of the terminal hydroxyl group, etc. are comprehensively related to each other, and show good shear thinning in an aqueous medium. It is assumed that In general, the fatty acid amide derivatives having shear thinning properties used in the present invention, when solubilized in an aqueous medium, have a.
There are cases where the particles are dispersed in fine particles of 5 μm or less, and cases where the particles are in a mixed state of solubilization and dispersion. Which state is determined by the balance between the lipophilic factor and the hydrophilic group factor. In addition, the type and amount of the water-soluble solvent and the additive for adjustment are also related, but the most characteristic feature of the fatty acid amide derivative that expresses shear thinning in the present invention is that at least a part of the fatty acid amide derivative in an aqueous medium. 0.5μ
It is necessary that the particles are dispersed in the form of fine particles having a particle size of m or less in order to provide stable shear thinning. Therefore, in a complete solution state having no dispersed structure of fine particles, no shear thinning is exhibited or the degree of shear thinning is so low that a shear thinning suitable for an aqueous ballpoint pen cannot be effectively exhibited.

As described above, the fatty acid amide derivative imparting a shear thinning effect in the present invention has a wide application and a high degree of freedom in compound selectivity. 1: 2 type, and in polyoxyethylene fatty acid amide, gel /
The strength and shear thinning of the sol can be adjusted. The number of moles of ethylene oxide to be added is adjusted depending on the length of the alkyl chain of the fatty acid (here, the number of moles to be added refers to the average number of moles added per substituent). It is preferable to adjust within the range. More preferably, the range of 1 to 5 mol is suitable. Further, by setting the blending amount of the fatty acid amide derivative in the ink to 6 to 30% by weight, stable shear thinning can be obtained. The development of excellent shear thinning in the high concentration region is a remarkable feature of the fatty acid amide derivative in the present invention. If the amount of the fatty acid amide in the ink is 6% by weight or less, sufficient shear thinning property cannot be obtained, and the smaller the amount, the more the shear thinning effect is lost.

The fatty acid amide derivatives usable in the present invention are specifically illustrated below, but are not limited to the compounds exemplified below. 2EO indicates that the number of moles added in the substituent of oxyethylene is 2.

The fatty acid monoethanolamides include myristic acid monoethanolamide, palmitic acid monoethanolamide, stearic acid monoethanolamide,
Use of one or a mixture of two or more of oleic acid monoethanolamide, isostearic acid monoethanolamide, linoleic acid monoethanolamide, ricinoleic acid monoethanolamide, and behenic acid monoethanolamide can be exemplified.

The fatty acid diethanolamides include myristic acid diethanolamide, palmitic acid diethanolamide, stearic acid diethanolamide, oleic acid diethanolamide, isostearic acid diethanolamide, linoleic acid diethanolamide, ricinoleic acid diethanolamide, behenic acid diethanolamide and the like. Examples thereof include 1: 1 type and 1: 2 type, and examples thereof include use of one type or a mixture of two or more types. Such a compound has a P.O. O. Corresponds to E fatty acid amide.

As the polyoxyethylene fatty acid amide, if the above-mentioned EO is one, P.I. O. E. FIG. Myristic acid amide (2 to 10 EO) O. E. FIG. Palmitic acid amide (2 to 10 EO) O. E. FIG. Stearamide (2 to 10 EO) O. E. FIG. Oleic acid amide (2 to 10 EO) O. E. FIG. Isostearic acid amide (2 to 10 EO) O. E. FIG. Linoleic acid amide (2 to 10 EO) O. E. FIG. Ricinoleic acid amide (2 to 10 EO) O. E. FIG. And behenic acid amide (2 to 10 EO). Here, 2 to 10 EO means that there are nine types of compounds, each having an average addition number of EO of 2 mol to 10 mol. Compounds that exhibit more preferable shear thinning viscosity include palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, ricinoleic acid, beveninic acid and 2
Fatty acid amide derivatives which are synthetic fatty acids which are liquid at 0 ° C. and have an addition mole number of ethylene oxide of 1-5.
More preferred compounds are, among the constituent fatty acids, oleic acid, linoleic acid, ricinoleic acid, isostearic acid, which are liquid fatty acids at 20 ° C., and 1 to 5 moles of ethylene oxide added to the synthetic fatty acid liquid at 20 ° C. The compounds of this group are excellent in viscosity stability against temperature change and stability in shear thinning.

As the colorant used in the ink composition of the present invention, all dyes and pigments that can be dissolved or dispersed in an aqueous medium can be used, and specific examples thereof are shown below. In the dyes, C.I. I. Acid dyes such as Blue 93,
Direct dyes such as Direct Black 154 and basic dyes such as rhodamine and methyl violet can be used.
Pigments include inorganic pigments such as carbon black and ultramarine blue, and organic pigments such as copper phthalocyanine blue and benzidine yellow, as well as water-dispersed pigment products that are already finely and stably dispersed in an aqueous medium using a surfactant. Can be easily used. More specifically, S.D. S. Blue GLL
(CI Pigment 15: 3B, pigment content 24
%, Manufactured by Sanyo Dyeing Co., Ltd.) S. Pink FBL
(CI Pigment Red 146, pigment content 2
1.5%, Sanyo Dyeing Co., Ltd.), TC Yellow
FG (CI Pigment Yellow 8)
1, pigment content: about 30%: manufactured by Dainichi Seika Industry Co., Ltd.), TC
Red FG (CI Pigment Red22
0/166, pigment content of about 35%, manufactured by Dainichi Seika Kogyo Co., Ltd.). As the fluorescent pigment, a fluorescent pigment in the form of fine particles of a synthetic resin in which various fluorescent dyes are dissolved in a resin matrix can be used, as well as pearl pigments, gold and silver metallic pigments, luminous pigments, and titanium oxide used in correction pens. And the like, and a perfume or perfume capsule pigment. In particular, the fatty acid amide derivative applied in the present invention can exhibit an effect as a pigment dispersant due to its surfactant effect and a high addition ratio in the ink composition. In particular, when a pigment having a relatively large particle system or a pigment having a large specific gravity difference from the aqueous medium of the ink is used, a more remarkable effect is exhibited. Furthermore,
As an application example of a useful pigment, a reversible thermochromic microcapsule pigment can be used. The above colorants can be used alone or in combination of two or more. The amount of these used is preferably from 1 to 35% by weight, and the setting of the added amount can be appropriately determined according to the coloration of the pigment itself and the purpose of use.

Next, an aqueous ballpoint pen ink composition exhibiting reversible thermochromic properties using a reversible thermochromic microcapsule pigment as a coloring agent will be described. The reversible thermochromic microcapsule pigment is composed of a thermochromic material composed of a homogeneous homogeneous solution of three essential components, an electron-donating color-forming organic compound, an electron-accepting compound, and a color-changing temperature regulator. A reversible color developing and erasing at a predetermined temperature by a conventional method, for example, JP-B-51-44706.
No., JP-B-51-44708, JP-B-52-7774
No., Japanese Patent Publication No. 51-35414, Japanese Patent Publication No. 1-29898
JP-A-7-186546, Japanese Patent Publication No. 4-1
No. 7154, JP-A-7-179777, and JP-A-7-33997, which are obtained by encapsulating the thermochromic material into fine particles by a known microencapsulation method or forming a resin matrix. .

The reversible thermochromic microcapsule pigment is made to exist in a dispersed state in the aqueous medium used in the present invention, and the thermochromic microcapsule pigment includes an electron-donating organic compound and an electron-accepting compound. And a homogeneous solution containing a reaction medium for controlling the discoloration temperature as an essential component coated with a wall film, and the particle distribution is 95% in a range of 0.5 μm to 20 μm.
(% By volume) or more.
Still more preferably, the reversible thermochromic microcapsule pigment is characterized in that it is a pigment comprising a wall film formed by interfacial polymerization or interfacial polycondensation having at least a portion of the outer surface, more preferably particles 0.5μ distribution
3 to 30% by weight (solid content) of a reversible thermochromic microcapsule pigment occupying 95% by volume or more in the range of m to 20 μm; 6 to 30% by weight of a fatty acid amide derivative exhibiting a shear thinning function; -30% by weight, with the balance consisting of water and conditioning additives, having a viscosity of 30-160.
m. Pa. s (value at 100 rpm in an EM-type rotational viscometer at 25 ° C.), and the shear thinning index of the ink is preferably in the range of 0.2 to 0.6.

Here, the reversible thermochromic microcapsule pigment is a pigment comprising a wall film formed by an interfacial polymerization or interfacial polycondensation method having a depression on at least a part of the outer surface thereof. The particles have pressure relaxation. As the shape of the microcapsule pigment,
Compared to a sphere having a perfect circular cross section (see FIG. 1), the shape of the surface having a dent (recess) on the surface (see FIGS. 2 to 5) shows the degree of destruction of the capsule itself even with the same viscosity ink. It is further relaxed. This is because even if the microcapsule pigment having the depression (recess) receives external force (such as pressure generated during writing), the stress is relaxed by its own elastic deformation.

Next, water is used as the main solvent in the ink composition for water-based ballpoint pens of the present invention, and any conventional general-purpose solvent having water compatibility as a water-soluble polar solvent is also effective.
Glycerin, triethanolamine, diethanolamine, monoethanolamine, ethylene glycol, diethylene glycol, thiodiethylene glycol, polyethylene glycol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, sulfolane, 2-pyrrolidone, N-methyl Pyrrolidone, such as -2-pyrrolidone, can be used. The amount used is 3 to 30% by weight, preferably 5 to 25% by weight in the composition.

As the adjusting additive, benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, diisopropylammonium nitrite, saponin and the like can be used as rust preventives. Examples of preservatives or fungicides include sodium carbonate, 1,2-benzthiazolin-3-one sodium salt, sodium benzoate, sodium dehydroacetate, potassium sorbate, propyl paraoxybenzoate, 2,3,5,6-tetra Chloro-
4- (methylsulfonyl) pyridine and the like. As the wetting agent, urea, nonionic surfactant, sorbit, mannitol, sucrose, glucose, reduced starch hydrolyzate, sodium pyrophosphate, etc. can be used.
In order to improve the permeability of the ink, a fluorine-based surfactant or a nonionic surfactant may be used. The above-mentioned adjustment additives are so-called conventional additives,
Known compounds can be used as needed.

The ink composition for water-based ballpoint pens of the present invention exhibiting shear thinning can impart the required shear-thinning property to the ink for water-based ballpoint pens only by using a fatty acid amide derivative exhibiting shear thinning. A polymer having substantially no shear thinning can be added for the purpose of imparting a binder or water resistance. Examples of such polymers include linear polymers such as polyvinyl alcohol, polyacrylic resin, and styrene maleic resin.
Further, a compound having a known shear thinning property can be used as required. Examples of such compounds include water-dispersible gums and resins, synthetic polymers, and inorganic fine particles having shear thinning properties. The shear thinning of the ink composition of the present invention refers to a rheological property that has a property of being extremely high in viscosity and hard to flow when in a static state or a low stress, and has a low viscosity and good flowability when the stress increases. . It means a common liquid property, also called thixotropic or pseudoplastic. The ink composition having a shear thinning property comprising the fatty acid amide derivative of the present invention has a three-dimensional structure that is temporarily broken under high shear stress during writing, the viscosity of the ink is reduced, and the ink near the ball is written. The ink becomes a low-viscosity ink suitable for the ink, and is moved by the capillary force in the gap between the ball and the ball house to be transferred and absorbed on the paper surface. At the time of non-writing, the viscosity of all inks including the vicinity of the ball becomes high, so that it is possible to prevent the leakage of the ink and the separation of the ink. Further, the physical properties of the ink can be stably maintained over time.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The aqueous ballpoint pen ink of the present invention is put to practical use by directly filling the ink into an ink storage portion. Next, a drawing regarding a ballpoint pen suitable for the present invention will be described (see FIGS. 6 to 11). A ball-point pen 1 suitable for the present invention is a ball-point pen 1 that includes a tip that rotatably holds a ball 2 and that is configured to draw out ink stored in an ink storage unit 4 to allow writing. Is filled with an aqueous ball-point pen ink composition 6. An ink follower 7 is arranged in contact with the rear end of the aqueous ball-point pen ink composition 6 stored in the ink storage section 4. In addition, the difference between the inner diameter A of the ball housing portion 3 for rotatably holding the ball 2 and the outer diameter B of the ball 2 is set to 10 to 60 μm, preferably 15 to 40 μm, and the ball 2 is moved in the axial direction by 15 μm. It is required to set the space C which can be moved to 100 μm, preferably 20 to 80 μm within the range according to the type of ink. Thus, a handwriting of an appropriate density is provided while satisfying a smooth writing feeling.

A general-purpose mechanism is effective for the structure of the writing tip as described above, and the vicinity of the tip of a metal pipe is pressed and deformed inward from the outer surface so that the ball receiving seat and the ink lead-out portion are formed. The tip portion is formed by a mechanism (see FIGS. 6 and 7) in which the tip portion of the tip is integrally formed, or by cutting a metal material with a drill or the like.
A mechanism for arranging 3, the central hole 31, and the radial lead-out groove 32 (see FIGS. 8 and 9) or a mechanism for urging the ball forward by a spring body (see FIG. 10) can be applied.

Next, the ink composition for an aqueous ballpoint pen of the present invention will be described. The present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In addition, the composition in an Example is shown by a weight part. In addition, the shear thinning index (n) in Examples is an empirical formula (T = Kj ⁿ : K and n obtained from rheological measurement using a viscometer such as a shear stress value (T) and a shear rate (j) value). (Which is a calculated constant).

Example 1 The ink was weighed at the compounding ratio described in the example, and then weighed at 50 ° C.
The mixture was stirred and dispersed under the following conditions. [Dye-based black ink] (parts by weight) Black dye [C. I. Direct black 20% aqueous solution] 13.9 Glycerin 7.0 Urea 7.0 Silicone-modified antifoaming agent 0.1 Carbonic acid 0.1 Oleic acid diethanolamide (1: 2 type) 22.7 [Product name: Polynon DAO, Iron Noyuka Chemical Co., Ltd.] Water 49.2． 100. 0 The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.35 Viscosity at 100 rpm: 67 m. Pa. s (25 ° C)

[Production of Ballpoint Pen] Using a metal ball having a diameter of 0.5 mm, a difference S (AB) between the inner diameter of the ball housing portion and the outer diameter of the ball = 20 μm, and an axially movable space C = 20 μm. A cutting-type ballpoint pen tip having a space was obtained. 1.2 g of the above ink composition was filled into a polypropylene pipe having an inner diameter of 3.3 mm, and connected to the ballpoint pen tip via a resin holder. Next, a viscoelastic ink follower (liquid stopper) made of polybutene was filled from the rear part of the polypropylene pipe, and after assembling the product, deairing was performed by centrifugation to obtain a ballpoint pen.

When continuous writing was performed on report paper using the ballpoint pen, clear black handwriting was obtained from the start of writing, and good writing performance was exhibited without blurring, line breaks, line breaks, and ink spotting.

Example 2 [Pigment-based red ink] (parts by weight) Red pigment dispersion 20.2 [SS RED RR 24% pigment content, Sanyo Dye Co., Ltd.] Glycerin 7.1 Propylene glycol 3.0 Urea 6 0.0 Silicone-modified antifoaming agent 0.1 Lithium carbonate 0.1 Benzotriazole 1.3 Oleic acid diethanolamide (1: 1 type) 12.1 [Stahome DO, manufactured by NOF CORPORATION] Water 50.1% ────────────────────────────────── 100.0 The physical properties of the ink composition were as follows: It was as follows. Shear thinning index (n) of the ink: 0.28 Viscosity at 100 rpm: 107 m. Pa. s (25 ° C)

[Production of Ballpoint Pen] A ballpoint pen was assembled in the same manner as in Example 1. When continuous writing was performed on report paper using the ballpoint pen, clear blue handwriting was obtained from the start, and good writing performance was exhibited without blurring, line breaks, line breaks, and ink spotting.

Example 3 [Pigment-based green ink] (parts by weight) Green pigment dispersion 20.8 [SS GREEN FBX pigment content 25%, manufactured by Sanyo Pigment Co., Ltd.] Glycerin 5.2 Diethylene glycol 5.2 Urea 6. 2 Silicone-modified antifoaming agent 0.1 Lithium carbonate 0.1 Benzotriazole 1.4 O. E (4) Stearic acid amide 6.2 [NIKKOL TAMDS-4, manufactured by Nikko Chemicals Co., Ltd.] Ethylene oxide adduct of stearic acid amide (5 mol on average) Water 54.8% １０ 100.0 The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.50 Viscosity at 100 rpm: 35 m. Pa. s (25 ° C)

[Preparation of Ballpoint Pen] Instead of a cutting-type ballpoint pen tip, a pipe tip mechanism is applied.
A ball-point pen equipped with a 0.5 mm stainless steel ball and having a ball housing portion having a space between a pipe inner diameter and a ball outer diameter, S (AB) = 30 μm, and an axially movable space C = 25 μm. I got a chip. The other members were assembled into a ballpoint pen according to Example 1.
When continuous writing on report paper using the ballpoint pen, a clear black handwriting is obtained from the start, blurring, line breaks, line breaks,
In addition, good writing performance was exhibited without any decrease in ink spots.

Example 4 [Pigment-based blue ink] (parts by weight) Blue pigment dispersion 20.2 [SS BLUE HB, pigment content 25%, Sanyo Dye Co., Ltd.] Glycerin 10.1 Urea 6.0 Silicone-modified Antifoaming agent 0.1 Nonionic surfactant [Lapisol B-30, manufactured by NOF Corporation] 1.0 Preservative [Proxel XL-2, manufactured by ICI] 0.1 Oleic acid diethanolamide (1: 2 type) 8.1 [Product name: Polynon DAO, manufactured by Tetsuno Yuka Co., Ltd.] Water 54.4 １０ 100.0 The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.39 Viscosity at 100 rpm: 123 m. Pa. s (25 ° C)

Preparation of Ballpoint Pen A ballpoint pen was assembled in the same manner as in Example 1 and continuous writing was performed. As a result, a dark pink handwriting was obtained from the start of writing, and there was no blurring, line breakage, line breakage, and ink bottling phenomenon. It showed good writing performance.

Example 5 [Fluorescent pigment-based pink ink] (parts by weight) Pink fluorescent pigment dispersion (Lumicoll 2117, manufactured by Nippon Fluorochemicals, Inc.) 20.8 Glycerin 10.4 Urea 6.2 Silicone-modified antifoam 0.1 Preservative [Proxel XL-2, manufactured by ICI] 0.1 O. E (5) Oleic acid amide 10.4 [NIKKOL TAMDO-5, manufactured by Nikko Chemicals Co., Ltd.] Water 52.0─────────────────────── １０ 100.0 The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.36 Viscosity at 100 rpm: 105 m. Pa. s (25 ° C)

[Preparation of Ballpoint Pen]
7mm, movable space S = 25μm, C = 45μ
A ballpoint pen was assembled in the same manner as in Example 1 except that m was changed to m. When continuous writing was performed on report paper using the ballpoint pen, clear fluorescent pink handwriting was obtained from the start of writing, and good writing performance was exhibited without blurring, line breaks, line breaks, and ink drop.

Example 6 [Fluorescent pigment-based orange ink] (parts by weight) Orange fluorescent pigment dispersion [Lumicol 2104, manufactured by Nippon Fluorescent Chemical Co., Ltd.] 21.8 Glycerin 6.5 Propylene glycol 6.5 Silicone-modified antifoam Agent 0.1 Calcium carbonate 0.1 Nonionic surfactant (Lapisol B30, manufactured by NOF CORPORATION) 1.0P. O. E (2) isostearamide 22.4 water 41.4 100.0 The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.39 Viscosity at 100 rpm: 72 m. Pa. s (25 ° C)

[Production of Ballpoint Pen] A ballpoint pen was assembled in the same manner as in Example 1 and continuous writing was performed. As a result, a dark orange handwriting was obtained from writing, and blurring, line breakage,
Good writing performance was exhibited without line breakage and ink bleeding.

Example 7 A method for preparing a thermochromic microcapsule pigment is described below. 6 parts of 6- (ethylisobutylamino) benzoheroran, 6 parts of bisphenol A, cetyl alcohol 30
Parts, 20 parts of stearyl caprate, 1 part of tinuvin 326 as a light-fastness-imparting agent, and 15 parts of an epoxy resin having an epoxy equivalent of 190 obtained by the reaction of bisphenol A and epichlorohydrin as a film material. The mixture was uniformly heated and melted, and emulsified in 100 parts of an aqueous protective colloid medium preliminarily heated to 70 ° C. with a homomixer so that the average particle size became 2.5 μm. Next, 5 parts of an aliphatic polyamine-based curing agent was added, and stirring was continued at 90 ° C. for 5 hours to obtain a microcapsule dispersion liquid by an interfacial polymerization method. The microcapsules were subjected to a centrifugal separation treatment in order to concentrate them, and 100 parts of a slurry-like material was obtained.
Met. Furthermore, in order to measure the particle size distribution, a centrifugal sedimentation type automatic particle size distribution analyzer (CAPA-3 manufactured by Horiba, Ltd.)
When the particle diameter is D, the relationship between the particle diameter and the occupied volume% (shown in parentheses) is as follows. A total of 97% of the above 0.5 μm ≦ D ≦ 20 μm was obtained, and the average particle diameter was 2.7 μm. Observation of the obtained microcapsules with a microscope confirmed that they were hemispherical flat capsules having concave portions (see FIGS. 2 to 5). The flatness increased as the particle size increased. The thermochromic microcapsule pigment thus obtained has a thermochromic property of about 2
The color was magenta at 7 ° C. or lower, and colorless at 32 ° C. or higher. Using the obtained microcapsules as a coloring agent, an aqueous ballpoint pen ink was prepared by the following formulation.

[Thermochromic Ink] (parts by weight) Thermochromic microcapsule pigment (solid content 65%) 16.5 Glycerin 6.9 Urea 4.1 Silicone-modified antifoaming agent 0.1 Phenolic acid 0.1 O. E (5) Oleic acid amide 11.0 [NIKKOL TAMDO-5, manufactured by Nikko Chemicals Co., Ltd.] Water 60.6─────────────────────── １０ 100.0 The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.47 Viscosity at 100 rpm: 81 m. Pa. s (25 ° C)

[Production of Ballpoint Pen] The diameter of the ball was set to 0.
7mm, movable space S = 25μm, C = 70μ
A ballpoint pen was assembled in the same manner as in Example 1 except that m was changed to m. When continuous writing was performed on report paper using the ballpoint pen, clear fluorescent pink handwriting was obtained from the start of writing, and good writing performance was exhibited without blurring, line breaks, line breaks, and ink drop. The thermal discoloration temperature of the handwriting was measured, and it was confirmed that the color was magenta at 27 ° C. or less and colorless at 32 ° C. or more, and there was no problem such as deterioration in the thermal discoloration function even after writing.

Example 8 The thermochromic composition of Example 7 was treated with 2- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-
Methylindol-3-yl) -4-azaphthalide 2.5
Thermochromic microcapsule pigment was obtained in the same manner as in Example 7, except that 5 parts of 2,2-bis (4-hydroxyphenyl) hexafluoropropane and neopentyl stearate were used instead. The moisture content of the capsule slurry is 32%, and the thermochromic microcapsule pigment obtained has a thermochromic property of blue below 14 ° C and colorless above 32 ° C, and has a wide hysteresis property between the two temperatures. ,
The two states of colors could be stored and held as desired. Using the obtained microcapsules as a coloring agent, an aqueous ballpoint pen ink was prepared by the following formulation.

[Thermochromic Ink] (parts by weight) Thermochromic microcapsule pigment (solid content 68%) 21.1 Pink fluorescent pigment dispersion [Lumicoll 2117, manufactured by Nippon Fluorescent Chemical Co., Ltd.] 5.3 Glycerin 8.2 Urea 4.9 Silicone-modified antifoaming agent 0.1 Lithium carbonate 0.1 Nonionic surfactant (Lapisol B30, manufactured by NOF Corporation) 0.8 Oleic acid diethanolamide (1: 2 type) 9 (Product name: Polynon DAO, manufactured by Tetsuno Yuka Co., Ltd.) Water 49.6 １０ 100.0 The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.35 Viscosity at 100 rpm: 76 m. Pa. s (25 ° C)

[Preparation of Ballpoint Pen]
7mm, movable space S = 25μm, C = 40μ
A ballpoint pen was assembled in the same manner as in Example 1 except that m was changed to m. When continuous writing was performed on report paper using the ballpoint pen, clear violet-colored handwriting was obtained from the start of writing, and good writing performance was exhibited without blurring, line breaks, line breaks, and ink spotting. In addition, the thermal discoloration of the handwriting was examined.
It was pink at 2 ° C. or higher, and it was confirmed that there was no problem such as deterioration of the thermochromic function even after writing.

Comparative Example 1 Oleic acid diethanolamide (1: 1) in Example 2
(Type 1) was replaced with water to prepare an ink composition.
The ink composition obtained as described above does not have any shear thinning property, and the ink bottling phenomenon occurs remarkably immediately after assembling into a ballpoint pen, and as a result of writing, the ink bottling is severe and unsuitable for writing. there were. The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 1.0 Viscosity at 100 rpm: 2.7 m. Pa. s (25 ° C)
[Measured using ELD viscometer]

Comparative Example 2 Oleic acid diethanolamide (1:
Preparation of an ink composition according to Example 4, except that lauric acid diethanolamide (1: 2 type) was used instead of
And a ballpoint pen. The physical properties of the ink composition were as follows. Shear thinning index (n) of the ink: 0.92 Viscosity at 100 rpm: 180 m. Pa. s (25 ° C.) The ink composition obtained as described above has no shear thinning property at all, and the ink bleeding phenomenon occurs remarkably immediately after assembling into a ball-point pen. The result was inappropriate.

The results of the writing tests of the inks in Examples 1 to 8 and Comparative Examples 1 and 2 and the evaluation of the stability over time are shown in the table.

[Table 1] The test items in the table are described below. Handwriting density and stability The intermittentness of writing lines, blurring and uniformity of density were observed and evaluated comprehensively. Ink leakage test The pen tip of the ball-point pen filled with the ink was turned downward in the air, and the state of the ink leaked from the pen tip after one hour had passed was visually observed and evaluated. The writing ballpoint pen was strongly pressed against the paper surface during writing and allowed to stand for 1 minute, and the size of the ink spread on the paper surface and the degree of local ink boiling in actual continuous loop writing were visually observed and evaluated. . A phenomenon in which the writing line appears double when the periphery of the line-breaking writing line is dark and the center portion is thin, and is likely to occur when the ink viscosity is increased in order to prevent ink leakage and bleeding. The handwriting was observed under a magnifying glass and the degree was evaluated.

[0050]

According to the ink composition for an aqueous ballpoint pen of the present invention, when a specific fatty acid amide derivative exhibiting a shear-thinning effect is combined with an aqueous vehicle containing a coloring agent, the shear-thinning function is effectively exhibited. When the ballpoint pen mechanism is filled with the ink for writing, the shear-thinning function is effectively developed, and the handwriting has a smooth writing feeling without causing line breaks, blurring, and dents. Satisfy writing performance. Further, a ballpoint pen which can stably maintain the shear thinning function and maintain desired writing performance and product characteristics can be provided.

Furthermore, a system using a thermochromic microcapsule pigment as a coloring agent can provide a thermochromic handwriting not found in a conventional ballpoint pen, and can be used for new applications. The specific examples are described below.

(1) Writing a secret character or picture on a postcard, a Christmas card, a greeting card, or the like with a thermochromic ballpoint pen that changes color at a temperature lower than room temperature, and then using it for magical purposes such that it appears when cooled. Using a ballpoint pen with color change (change from one color to another)
You can enjoy colorful patterns and discoloration of characters at body temperature and hand temperature.

(2) As a secret pen, the discoloration temperature is 10 ° C.
The use of a thermochromic colorant that develops color only in the cold state or a thermochromic colorant having hysteresis characteristics in a wide temperature range enables recording that cannot be read at room temperature, and is suitable for memos that require confidentiality.

(3) A useful effect can be exhibited even when the thermochromic pigment having hysteresis characteristics is used for learning. That is, for a collection of questions, tests, drills, blank maps, English translations, necessary answers and supplementary items are written with a thermochromic aqueous ballpoint pen, heated and erased, and there are no completely reset answers or notes. Once again, the problem can be tackled again, satisfying the repetitive applicability. Such a use is also possible using a thermochromic ballpoint pen that changes color at 10 ° C. In any case, characters and the like can be re-colored using a cooling / discoloring tool having a cooling surface filled with a refrigerant such as ice in a container. It can also be provided as a product combining thermochromic ballpoint pens and teaching materials.

(4) A message such as "HAPPY BIRTHDAY" appears when a message is written on the side of the paper cup with a thermochromic aqueous ballpoint pen with a color change of 10 ° C. and a cold drink is poured. Because you can easily form an image on the spot,
It is suitable for party supplies and fancy goods, and provides an unprecedented message effect. It can also be provided as a set of paper cups and thermochromic ballpoint pens.

(5) The use of the thermometer is as follows.
By setting a plurality of thermochromic water-based ballpoint pens having different discoloration temperatures and forming an appropriate image, it can be used for easily measuring the temperature of the object. In addition, if characters, symbols, and patterns are configured by appropriately combining pens with different temperatures, the patterns can be changed in various ways with changes in temperature. Such applications include various industrial fields, for example, temperature control of reaction tanks, temperature control in processing processes, indicators for proper temperature control of low-temperature circulating foods, temporary displays such as a display for preventing overheating due to short-circuiting of an electrical cord outlet, and of course, a long display. This is convenient for use in displaying temperature detection during a period.

(6) In the field of clothing, when illustrations and patterns are drawn on a casual wear such as a T-shirt with a thermochromic water-based ballpoint pen that changes color at 30 ° C., a color utilizing the temperature difference between outdoor and indoor in summer. A changing T-shirt can be obtained. The T-shirt can be designed by oneself, and can also be written on gloves, shoes, hats, ski wear, swimwear, and the like.

(7) There is an application as a substitute for the chaco function in the sewing processing field. That is, the guide lines can be erased by writing the guide lines in the ink-colored state of a thermochromic ballpoint pen having a memory property, and then heating the iron to a temperature exceeding the high-temperature side discoloration point after sewing. As an example of the memory discoloration function for such applications,
A thermochromic ink having a low-temperature side discoloration point of −10 ° C. and a high-temperature side discoloration point of about 40 ° C. can be applied.

(8) In the field of forgery prevention, the ballpoint pen of the present invention can be used to write symbols, characters, and the like, and by cooling or heating, it is possible to discriminate between a genuine article and a forged one. For example, it is effective as a personal store or a small lot scale for preventing forgery by handwriting such as tickets, cash vouchers, and coupons. If desired, the discoloration temperature, discoloration type, and color can be marked by date and period by themselves, which is effective for applications requiring short-term identification.

(9) It is also effective in the field of toys. For example, it is possible to write a design on a specific portion of the surface of a stuffed toy and warm it up at body temperature to enjoy its discoloration, or to use it around the lips, nails and eyes of a doll. Lipstick, nail polish,
Coloring with a thermochromic ballpoint pen with memory of eyeshadow color and using a discoloration tool using hot and cold water to be able to repeatedly play the two states of "makeup state" and "non-makeup state" There is a degree of freedom to make up with free colors and patterns to satisfy creativity. In addition, the user can freely design a dress-up dress made of paper or cloth by himself and enjoy the discoloration. For toys, a ballpoint pen with a slightly larger ball (1-2 mm in diameter) is effective for enhancing the effect of discriminating handwriting.

(10) As a drawing pen for designers, use a memory-type thermochromic ballpoint pen to make a rough sketch in the color development state, and then write the final design or picture with general art materials and then heat it. It is also effective for applications such as erasing line drawings of rough sketches.

(11) If it becomes difficult to create a number or symbol with a thermochromic ballpoint pen so that the position of the completed jigsaw puzzle when it is fitted can be confirmed in advance, Thus, it is possible to confirm the position to be fitted after cooling.

(12) Low temperature discoloration temperature 1 for face photographs, paintings, etc.
Graffiti is drawn with a thermochromic ballpoint pen at 0 ° C and a high-temperature discoloring temperature of 35 ° C. Then, if it is heated to 35 ° C. or more, it returns to the state before graffiti.

(13) A horizontal line is added to the candy lot formed by drawing with a printing or general writing instrument with a thermochromic ballpoint pen of the same color. Then, at the time of lottery,
When heating or cooling, the horizontal line increases or decreases, so the person who wins the hit differs.

(14) Characters and pictures are written on the orbit for moving the sugoroku top using a thermochromic ballpoint pen. Then, when you move the piece with ice, characters and pictures appear.

(15) Write characters and pictures on the paper with a thermochromic ballpoint pen. Then, when the paper which is plain at room temperature is applied to a cooling device (for example, a simulated printing machine incorporating ice), it becomes as if characters and pictures were printed. Also, when writing characters and pictures with a thermochromic ballpoint pen that presents multiple colors,
It is possible to indicate a state where color printing is performed.

(16) Write characters and pictures on stickers and stickers with a thermochromic ballpoint pen. When the seal or the sticker is attached to a beverage container or the like, various changes in form can be enjoyed due to a change in temperature. Also, it can be used as an indicator or a remaining amount display.

(17) Name, address, etc. are written on the property with a thermochromic ballpoint pen. Then, since the color is normally erased, the appearance of the article is not spoiled. Further, when cooled, the name, address, and the like become visible, and the owner can be confirmed.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of the outer shape of an example of a microcapsule pigment. (A) shows the appearance, and (B) shows a sectional view.

FIG. 2 is a schematic explanatory view of the outer shape of another example of a microcapsule pigment. (A) shows the appearance, and (B) shows a sectional view.

FIG. 3 is a schematic explanatory view of the outer shape of another example of a microcapsule pigment. (A) shows the appearance, and (B) shows a sectional view.

FIG. 4 is a schematic explanatory view of the outer shape of another example of a microcapsule pigment. (A) shows the appearance, and (B) shows a sectional view.

FIG. 5 is a schematic explanatory view of the outer shape of another example of the microcapsule pigment. (A) shows the appearance, and (B) shows a sectional view.

FIG. 6 is an explanatory longitudinal sectional view of one embodiment of the tip portion of the ballpoint pen of the present invention.

FIG. 7 is a sectional view taken along line XX of FIG. 6;

FIG. 8 is an explanatory longitudinal sectional view of another example of the tip portion of the ballpoint pen of the present invention.

FIG. 9 is a sectional view taken along line XX of FIG. 8;

FIG. 10 is an explanatory longitudinal sectional view of another example of the tip portion of the ballpoint pen of the present invention.

FIG. 11 is an explanatory longitudinal sectional view of one embodiment of the ballpoint pen of the present invention.

[Explanation of symbols]

1 Ballpoint pen 2 balls 3 Ball storage 31 center hole 32 outlet hole 33 Ball seat 4 Ink storage section 5 Microcapsule pigments 51 Membrane wall 52 hollow 53 Thermochromic composition 6 Ink composition for aqueous ballpoint pen 7 Ink follower A Inner diameter B Outline C space

Claims (13)

(57) [Claims] Claims: 1. An essential component comprising 6 to 30% by weight of a colorant, water, a water-soluble polar solvent and a fatty acid amide derivative represented by the following general formula (1) exhibiting a shear thinning function.
Wherein the fatty acid amide derivative is at least partially dispersed.
It is maintained in a state and develops and maintains the shear thinning function.
An aqueous ball-point pen ink composition characterized by having the following constitution . General formula (1) [Here, R represents a straight-chain or side-chain alkyl group having 13 to 21 carbon atoms and an unsaturated alkyl group, m represents 0 to 10, and n represents 1 to 10. ] 2. The method according to claim 1, wherein the fatty acid amide derivative is contained in an ink.
And a phase in a dispersed state in the form of fine particles of 0.5 μm or less,
Substantially dissolved and in a molecular association state in a mixed state
The aqueous ink composition for a ballpoint pen according to claim 1, which exhibits shear thinning . 3. The method of claim 1, wherein the fatty acid amide derivative has the following general formula:
A process comprising a fatty acid amide derivative represented by (2)
3. The ink composition for an aqueous ballpoint pen according to claim 1 or 2 . General formula (2) [Where R is a straight-chain or side-chain alkyl having 13 to 21 carbon atoms]
And n represents 1 to 5
You. ] 4. The aqueous ball-point pen ink composition according to claim 1 , which has a shear thinning index of 0.1 to 0.6 . 5. The aqueous ball-point pen ink composition according to claim 1 ,
Coloring agent 1 to 35% by weight, fatty acid exhibiting shear thinning function
Amide derivative 6 to 30% by weight, water-soluble polar solvent 3 to 30
% By weight, the balance being water and conditioning additives,
30-160 m. Pa. s (in EM type rotational viscometer)
In the range of 100 rpm) and shear thinning
The aqueous ballpoint pen ink composition according to any one of claims 1 to 4 , which satisfies an index of 0.1 to 0.6 . 6. The fatty acid amide derivative has 14 to 2 carbon atoms.
Composed of fatty acids that are liquid at 20 ° C
One or more of the fatty acid amide derivatives
Low total amount of fatty acid amide derivative
6. The method according to claim 1, wherein the content is at least 50% by weight.
An aqueous ink composition for ballpoint pens. 7. The aqueous ball-point pen ink composition according to claim 1 , wherein the colorant is a pigment . 8. A reversible thermochromic microcapsule wherein the colorant is reversible.
The aqueous ball-point pen ink composition according to any one of claims 1 to 7 , which is a pigment and exhibits reversible thermochromic properties . 9. A reversible thermochromic microcapsule pigment,
Electron-donating color-forming organic compounds, electron-accepting compounds and modifications
Homogeneous phase solution containing a reaction medium that controls color temperature as an essential component
Is coated with a wall film, and the particle distribution is 0.5 μm to 20 μm.
9. A pigment occupying 95% by volume or more in the range of m.
Water-based ballpoint pen ink composition for. 10. A reversible thermochromic microcapsule pigment.
Is an interfacial polymerization having a depression on at least a part of the outer surface or
Is a pigment consisting of a wall film formed by the interfacial polycondensation method.
The aqueous ball-point pen ink composition according to claim 8 . 11. A particle distribution in a range of 0.5 μm to 20 μm.
Ripening microcapsules occupying 95% by volume or more
Cell pigment 3 to 30% by weight (solid content), with shear thinning function
Fatty acid amide derivatives 6-30% by weight expressed, soluble polar
Containing 3 to 30% by weight of a neutral solvent, with the balance being water and adjusting additives
Having a viscosity of 30 to 160 m. Pa. s (EM type times
Value at a rotational speed of 100 rpm in a viscometer).
Yes, the shear thinning index is in the range of 0.2 to 0.5
Item 10. The aqueous ball-point pen ink composition according to any one of Items 8 to 10 . 12. A chip for rotatably holding a ball.
Draw out the ink stored in the ink storage section and write
In the ballpoint pen configured so as to be capable of storing the ink,
In the part, colorant, water, water-soluble polar solvent and
Fatty acid amide derivative that exhibits shear and shear thinning function
An aqueous ballpoint pen according to any one of claims 1 to 11, wherein
The ink composition for use is stored in a direct liquid state.
And a ballpoint pen. 13. The ink storage section comprises a pipe,
At the rear end of the water-based ink composition for ballpoint pens
13. The ballpoint pen according to claim 12, further comprising an ink follower.
N.