JPH09316382A - Water-based pigment ink for ballpoint pens - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: Even a ballpoint pen using an ink containing titanium oxide as a coloring material can be written smoothly, and the ink can be used up to the end. A titanium oxide, a thickening water-soluble resin, a binder, a water-soluble organic solvent, an N-fatty acid acyl-L-glutamate, and water are contained at least.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-based pigment ink for ball-point pens, which uses titanium oxide as a coloring material and, if necessary, further contains a chromatic color pigment to obtain a white or pastel color tone. The present invention relates to a water-based pigment ink for a ballpoint pen, in which the wear of the ball seat due to solid matter such as titanium oxide is prevented as much as possible during rotation, thereby ensuring good ink dischargeability.

[0002]

2. Description of the Related Art Conventionally, titanium oxide is used as a coloring material in order to obtain white handwriting. Further, in order to obtain a pastel-like handwriting, titanium oxide and a chromatic color pigment are used in combination as a coloring material.

An ink using titanium oxide is disclosed in JP-A-4-
It is disclosed in Japanese Patent No. 258677 and Japanese Patent Laid-Open No. 59-2177776. An ink in which titanium oxide and a chromatic pigment are used in combination is disclosed in JP-A-8-9704.

By the way, as an ink for a ballpoint pen using a pigment as a coloring material, Japanese Patent Application Laid-Open No. 59-74175 discloses xanthan gum in an amount of 0.20 to 20% with respect to the total amount of the ink.
An aqueous ballpoint pen ink composition containing 0.45% by weight is disclosed.

[0005]

DISCLOSURE OF THE INVENTION Ink dischargeability when an ink using titanium oxide as a colorant is used as an ink for ballpoint pen. White handwriting uses black or other dark colored paper as writing paper. Moreover,
The amount of ink discharged from the ball-point pen is smaller than that of other writing instruments such as felt-tip pens. Therefore, this type of ink is required to have high hiding power. In order to impart high hiding power to the ink, there is a method of increasing the amount of titanium oxide used as a coloring material, which is generally used. Regarding increasing the amount of titanium oxide used,
Even in the case of a pastel-type ink in which titanium oxide and a chromatic color pigment are used in combination, it is adopted for the same reason.

However, when the content of titanium oxide in the ink increases, the wear of the ball seat becomes larger during writing, and as a result, the ink conducting hole of the ball-point pen tip is blocked by the ball, and finally Is likely to cause a problem that ink is not ejected.

An object of the present invention is an ink using titanium oxide as a coloring material, which reduces wear of the ball seat as much as possible,
An object of the present invention is to provide a water-based pigment ink for a ballpoint pen, which prevents the ink discharge amount from decreasing with time.

[0008]

The present invention contains at least titanium oxide, a thickening water-soluble resin, a binder, a water-soluble organic solvent, N-fatty acid acyl-L-glutamate, and water. A water-based pigment ink for a ballpoint pen, which is characterized by the above.

Hereinafter, the present invention will be described in detail. The titanium oxide used in the present invention is used as a coloring material or a masking material, and various types of titanium oxide such as rutile type and anatase type can be used. As commercially available titanium oxide,
Thaitone SR-1, Same R-650, Same R-3L, Same A
-150, the same R-5N (above, Sakai Chemical Industry Co., Ltd.),
Taipaque R-580, Same R-930, Same A-100,
A-220, CR-58 (above Ishihara Sangyo Co., Ltd.)
), Kronos KR-310, the same KR-380, the same KR
-480, the same KA-10, the same KA-20, the same KA-30
(Above, manufactured by Titanium Industry Co., Ltd.), TYPURE R-90
0, the same R-931 (above, manufactured by DuPont Japan Limited), Titanics JR-300, the same JR-60.
0A, the same JR-800, the same JR-801 (above, Teika Co., Ltd. make) etc. are mentioned. The amount used is preferably 20 to 35% by weight with respect to the total amount of the water-based pigment ink for the present ballpoint pen. If it is less than 20% by weight, the hiding power of the handwriting will be reduced, and if it exceeds 35% by weight, the writing feeling will be poor and the ink discharge amount will be small.

The water-soluble resin for thickening is used for adjusting the viscosity of the ink, and it is more preferable that the effect is exhibited by a small addition amount. Specifically, polyvinylpyrrolidone, polyethylene oxide, polyacrylate,
Synthetic (co) polymers such as methyl vinyl ether maleic anhydride copolymer, and cellulosic polymers such as sodium carboxymethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose,
In addition to natural polymers such as guar gum, xanthan gum, welan gum, rumzan gum, and locust bean gum, hydrogenated castor oil, gelling agents such as polycarboxylic acid amide, and the like can be mentioned. These thickening water-soluble resins may be used alone or in combination of two or more. The amount used is such that the water-based pigment ink for this ballpoint pen has an appropriate viscosity (6000 to 6000).
50,000 mPa · s), but 0.1% of the total amount of the water-based pigment ink for this ballpoint pen
~ 2.0% by weight is preferred.

The binder is used for fixing the ink coating film on the paper surface. Specifically, styrene-
Alkali metal salt of acrylic acid copolymer, amine salt, ammonium salt, alkali metal salt of α-methylstyrene-acrylic acid copolymer, amine salt, ammonium salt, alkali of styrene-acrylic acid ester-acrylic acid copolymer In addition to water-soluble resins such as metal salts, amine salts, and ammonium salts, acrylic resins, vinyl acetate-based resins, water-insoluble resins such as styrene-butadiene copolymers, etc. may be mentioned. The water-insoluble resin is used in the form of an aqueous emulsion. The amount used is preferably 3 to 20% by weight based on the total amount of the aqueous pigment ink for the present ballpoint pen.

The water-soluble organic solvent is used for various qualities as an ink, for example, for the purpose of preventing the ink from freezing at low temperatures and preventing the ink from drying at the pen tip. Specifically, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol,
Glycols such as polyethylene glycol, 3-butylene glycol, thiodiethylene glycol and glycerin, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, 2-pyrrolidone, triethanolamine and the like can be used alone or in combination. The amount used is preferably 5 to 30% by weight based on the total amount of the water-based pigment ink for the present ballpoint pen.

The N-fatty acid acyl-L-glutamate is used as a lubricant for preventing wear of the ball seat. Specific examples thereof include N-coconut oil fatty acid acyl-L-sodium glutamate and N-lauroyl-L.
-Sodium glutamate, N-stearoyl-L-potassium glutamate and the like can be mentioned, and these can be used alone or in combination. The amount used is preferably 0.1 to 5.0% by weight with respect to the total amount of the water-based pigment ink for the present ballpoint pen. If it is less than 0.1% by weight, the lubricating effect may not be sufficient, and if it exceeds 5.0% by weight, the pigment easily penetrates into the paper when written on highly penetrable paper such as black drawing paper. And the handwriting may become thin.

[0014] Water is used as the main solvent.

The water-based pigment ink for ballpoint pens of the present invention comprises
It is preferably 6000 to 50000 mPA · s. This is an easy-to-write ink for ballpoint pens,
This is to ensure good ink ejection and sufficient handwriting density. When the ink viscosity is lower than 6000 mPa · s, the sedimentation and separation of the pigment becomes large, and the handwriting density becomes extremely low especially when it is left upward, and
When it is higher than Pa · s, the ink ejection property is low and it becomes difficult to write.

Further, in the present water-based pigment ink for ballpoint pens, the addition of resin particles reduces the average specific gravity of the solid content in the ink, which is effective for the sedimentation of titanium oxide. It is also effective in preventing the penetration of Examples of the material of the resin particles include polyethylene, polypropylene, vinyl chloride, polymethacrylate, benzoguanamine, nylon and the like, and examples of the shape include a spherical shape, an irregular shape and a hollow shape. Furthermore,
Those colored with a dye or the like can also be used. Specific examples of the resin particles include MP-1000 (polymethyl methacrylate, manufactured by Soken Chemical Industry Co., Ltd.), Eposter S (melamine-formaldehyde condensate, Nippon Shokubai Chemical Co., Ltd.).
Manufactured), nylon SP (nylon, manufactured by Toray Industries, Inc.), vinyl chloride # 121 (vinyl chloride, manufactured by Nippon Zeon Co., Ltd.) and the like. Specific examples of hollow resin particles include MH
5055 (solid content 20%) (manufactured by Zeon Corporation), S
X863 (A) (solid content 20%), SX864 (B)
(Solid content 40%) SX865 (B) (Solid content 48%)
(Above, manufactured by Nippon Synthetic Rubber Co., Ltd.), Lowpaque OP-6
2 (solid content 42.5%), the same OP-84J (solid content 3
7.5%), OP-91 (solid content 27.5%) (above, manufactured by Rohm and Haas Japan Co., Ltd.) and the like. Specific examples of the resin particles colored with a dye include SW-11 (red and orange, color tone, the same applies hereinafter), SW-12 (green), SW-13 (red), SW-14 (orange), SW- 15 (lemon
Yellow), SW-16 (Orange / Yellow), SW
-17 (pink), SW-27 (rose), SW-37
(Rubin), SW-47 (Violet), SW-18
(Blue), (above, manufactured by Shin Roihi Co., Ltd.), LUMI
KOL NKW-2101 (red orange), same NK
W-2102 (green), NKW-2103 (red), NKW-2104 (orange), NKW-2
108 (blue), NKW-2117 (pink), NKW-2127 (rose), NKW-2137 (rubin), NKW-2167 (violet) (above,
Nonvolatile content 51-54%) (Nippon Fluorescent Chemical Co., Ltd.)
Manufactured). The above resin particles are of one type or two types.
It is possible to use a mixture of two or more species. The amount used is preferably 2 to 15% by weight as a solid content. If it is less than 2% by weight, the effect of preventing penetration of titanium oxide into paper may not be sufficient, and if it exceeds 15% by weight, the content of titanium oxide in the ink is reduced, so that the handwriting hiding property is reduced. It may get worse.

In the water-based pigment ink for the present ballpoint pen,
When a pastel tone is required as the color of the handwriting, inorganic pigments such as ultramarine blue, navy blue, cobalt blue, titanium yellow, turquoise and molybdate orange, and C.I.
I. Pigment Red 2, the same 3, the same 5, the same 17, the same 2
2, ibid 38, ibid 41, ibid 48: 2, ibid 48: 3, ibid 4
9, ibid 50: 1, ibid 53: 1, ibid 57: 1, ibid 58:
2, the same 60, the same 63: 1, the same 63: 2, the same 64: 1, the same 88, the same 112, the same 122, the same 123, the same 144, the same 1
46, 149, 166, 168, 170, 1
76, 177, 178, 179, 180, 1
85, 190, 194, 206, 207, 20
9, 216, 245, C.I. I. Pigment Orange 5, the same 10, the same 13, the same 16, the same 36, the same 40, the same 4
3, C.I. I. Pigment Violet 19, the same 23, the same 31, the same 33, the same 36, the same 38, the same 50, C.I. I. Pigment Bull-2, the same 15, the same 15: 1, the same 15: 2, the same 15: 3, the same 15: 4, the same 15: 5, the same 16, the same 17,
22, 25, 60, 66, C.I. I. Pigment Brown 25 and 26, C.I. I. Pigment Yellow-
1, the same 3, the same 12, the same 13, the same 24, the same 93, the same 94,
Ibid 95, ibid 97, ibid 99, ibid 108, ibid 109, ibid 11
0, 117, 120, 139, 153, 16
6, 167, 173C. I. Pigment Greens 7, 10, and 36 may be used.

In addition to the above resin particles, various additives used in water-based inks for writing instruments can be used as needed. For example, to prevent evaporation of ink, sugar alcohols such as sorbit and xylit, wetting agents such as urea, ethyleneurea, and thiourea, preservatives such as benzothiazoline and omadine, and rust inhibitors such as benzotriazole, etc. , Surfactants and the like.

Various methods can be adopted for producing the water-based pigment ink for ballpoint pens of the present invention. For example, the above components are blended and dispersed in a ball mill, a sand grinder, a speed line mill, a triple roll or the like. It can be easily obtained by mixing and dispersing with a machine.

[0020]

In general, a free-cutting alloy is used for the pen tip of a ball-point pen because precision machining is required. Free-cutting alloys include ferritic or martensitic stainless steels, nickel silver, brass, etc., and tungsten carbide (cemented carbide) is mainly used as the ball material. The water-based pigment ink for the present ballpoint pen has N-fatty acid acyl-L in the ink.
-The nitrogen atom of glutamate is adsorbed by iron or copper in the above free-cutting alloy, and the hydrophobic group in the molecule faces outward, playing a cushion-like role between the ball and the ball seat. As a result, wear of the receiving seat during use is suppressed, and the ink conduction hole is not blocked by the ball.
It shows good ink ejection properties until the ink is used up.

[0021]

The present invention will be described below in more detail with reference to examples. Example 1 Chronos KR380 (titanium oxide) 30.0 parts by weight 6% by weight aqueous solution of xanthan gum 7.9 parts by weight Johncryl J61J (styrene-acrylic copolymer ammonium salt, manufactured by Johnson Polymer Co., Ltd.) 6.0 parts by weight Parts Ethylene glycol 3.0 parts by weight Glycerine 3.0 parts by weight N-coconut oil fatty acid acyl-L-sodium glutamate 2.0 parts by weight Water 35.1 parts by weight LUMIKOL NKW2108 (resin particles solid content 53% by weight) 12.0 Parts by weight TL10 (POE (20) sorbitan monolaurate, manufactured by Nikko Chemicals Co., Ltd.) 1.0 parts by weight LUMIKOL NKW2108, a 6% by weight aqueous solution of xanthan gum, N-coconut oil fatty acid acyl-L- Sodium glutamate and other ingredients are mixed,
After performing dispersion processing with a ball mill for 24 hours, LUMIK
OL NKW2108, xanthan gum 6% by weight aqueous solution, N-coconut oil fatty acid acyl-L-sodium glutamate were added and stirred for 1 hour to give a viscosity of 20,000 mPas.
・ S (ST rotor of E type viscometer, 1 rpm, 25 ° C)
To obtain a pigment aqueous ink for a ballpoint pen.

Example 2 TYPURE R900 (titanium oxide) 28.0 parts by weight Jaguar HP60 (guar gum derivative, manufactured by Sansei Co., Ltd.) 3% by weight aqueous solution 16.0 parts by weight Johncryl J711 (acrylic emulsion, Johnson polymer) 5.0 parts by weight Ethylene glycol 2.5 parts by weight Glycerin 2.0 parts by weight Sodium N-stearoyl-L-glutamate 0.1 parts by weight Water 13.4 parts by weight PO20 (sugar alcohol, solid content 75) %, Manufactured by Towa Kasei Co., Ltd. 2.0 parts by weight NP15 (POE (15) nonylphenyl ether, manufactured by Nikko Chemicals Co., Ltd.) 1.0 part by weight SX863 (A) (hollow resin particles, solid content 20%) ) 30.0 parts by weight In the above components, each component other than a 3% by weight aqueous solution of Jaguar HP60 is mixed, and a ball mill is used. After 24 hours dispersion treatment, the addition of 3 wt% aqueous solution of Jaguar HP60 1
Stirring was performed to obtain a pigment ink for a ballpoint pen having a viscosity of 10,000 mPa · s (ST rotor of E type viscometer, 1 rpm, 25 ° C.).

Example 3 Chronos KR380 (titanium oxide) 30.0 parts by weight 6% by weight aqueous xanthan gum solution 7.9 parts by weight Jonkryl J61J (previously described) 6.0 parts by weight ethylene glycol 3.0 parts by weight glycerin 3.0 Parts by weight N-lauroyl-L-sodium glutamate 5.0 parts by weight water 32.1 parts by weight LUMIKOL NKW2108 (described above) 12.0 parts by weight TL10 (described above) 1.0 parts by weight LUMIKOL NKW2108, xanthan gum A 6% by weight aqueous solution and each component other than N-lauroyl-L-sodium glutamate were mixed and subjected to a dispersion treatment for 24 hours by a ball mill, and then LUMIKOL N
KW210, an aqueous solution of 6% by weight xanthan gum, and sodium N-lauroyl-L-glutamate are added and stirred for 1 hour, and a pigment aqueous ink for a ballpoint pen having a viscosity of 20000 mPa · s (ST rotor of E type viscometer, 1 rpm, 25 ° C). Got

Example 4 Chronos KR380 (described above) 30.0 parts by weight Phthalocyanine blue 5.0 parts by weight 6% by weight aqueous solution of xanthan gum 7.9 parts by weight Johncryl J61J (described above) 6.0 parts by weight Ethylene glycol 3 0.0 parts by weight glycerin 3.0 parts by weight N-coconut oil fatty acid acyl-L-glutamate potassium 2.0 parts by weight water 30.1 parts by weight MH5055 (hollow resin particles, solid content 20 parts by weight, manufactured by Zeon Corporation) ) 12.0 parts by weight TL10 (previously described) 1.0 parts by weight In each of the above components, MH5055, a 6% by weight aqueous solution of xanthan gum, N-coconut oil fatty acid acyl-L-potassium glutamate and other components are mixed and mixed in a ball mill. After the dispersion treatment for 24 hours, MH5055, an aqueous solution of 6% by weight of xanthan gum, N-coconut oil fatty acid acyl-L It was stirred for 1 hour by the addition of potassium glutamate, viscosity 2000
0 mPa · s (ST rotor of E type viscometer, 1 rpm,
A pigment aqueous ink for ballpoint pens at 25 ° C. was obtained.

Example 5 Kronos KR380 (described above) 28.0 parts by weight 6% by weight aqueous solution of xanthan gum 7.9 parts by weight Jonkryl J61J (described above) 6.0 parts by weight Ethylene glycol 3.0 parts by weight Glycerin 3.0 Parts by weight N-coconut oil fatty acid acyl-L-sodium glutamate 0.05 parts by weight Water 39.05 parts by weight LUMIKOL NKW2108 (previously described) 12.0 parts by weight TL10 (previously described) 1.0 parts by weight LUMIKOL NKW2108 , 6% by weight aqueous solution of xanthan gum, and each component other than sodium N-coconut oil fatty acid acyl-L-glutamate were mixed and dispersed by a ball mill for 24 hours.
IKOL NKW2108, xanthan gum 6% by weight aqueous solution, N-coconut oil fatty acid acyl-L-glutamate sodium were added and stirred for 1 hour, viscosity 18500 m
Pa · s (ST rotor of E type viscometer, 1 rpm, 25
A pigment-based aqueous ink for ballpoint pens was obtained.

Example 6 Chronos KR380 (previously described) 30.0 parts by weight 6% by weight aqueous solution of xanthan gum 7.9 parts by weight Johncryl J61J (previously described) 6.0 parts by weight Ethylene glycol 3.0 parts by weight Glycerin 3.0 Parts by weight N-coconut oil fatty acid acyl-L-sodium glutamate 5.5 parts by weight water 31.6 parts by weight LUMIKOL NKW2108 (previously mentioned) 12.0 parts by weight TL10 (previously mentioned) 1.0 parts by weight LUMIKOL NKW2108 , 6% by weight aqueous solution of xanthan gum, and each component other than sodium N-coconut oil fatty acid acyl-L-glutamate were mixed and dispersed by a ball mill for 24 hours.
IKOL NKW2108, xanthan gum 6% by weight aqueous solution, N-coconut oil fatty acid acyl-L-glutamate sodium were added and stirred for 1 hour, viscosity 18500 m
Pa · s (ST rotor of E type viscometer, 1 rpm, 25
A pigment-based aqueous ink for ballpoint pens was obtained.

Comparative Example 1 An ink was obtained in the same manner as in Example 1 except that water was added in place of N-coconut oil fatty acid acyl-L-glutamate sodium.

Comparative Example 2 An ink was obtained in the same manner as in Example 4 except that water was added instead of N-coconut oil fatty acid acyl-L-glutamate potassium.

As described above, the water-based pigment inks for ball-point pens obtained in Examples 1 to 4 and Comparative Examples 1 to 2 were prepared by using a ball-point pen tip using a ball (material: super hard) having a diameter of 0.8 mm at one end of a polypropylene cylinder. 0.8g was filled in the ball-point pen cylinder that was fitted inside, and 0.1g of ink backflow prevention body was further filled on the ink to make a ball-pen refill, and the ink and bubbles in the ink backflow prevention body were centrifuged. After deaeration, a written test was conducted. The results are shown in Table 1.

[0030]

[Table 1]

Writing test Writing conditions: Writing speed 7 cm / sec, writing angle 70 ° C.,
Writing load 200 g Writing paper: Fine paper (JIS P3201 Writing paper A) Test method: Writing is performed under the above-mentioned writing conditions, and writing is performed until the handwriting becomes faint. Evaluation: The sinking amount of the ball and the ink consumption amount were measured. Ball sinking = Ball out before writing-ball out at the end of writing

In the above writing test, the handwriting of Example 6 had a large penetration of the coloring material into the paper, and the density was slightly lower than that of the other Examples. Further, in Comparative Examples 1 and 2, the line jumped immediately after writing, the directionality was remarkable, and the handwriting was blurred when ½ of the ink was used.

[0033]

As described above in detail, the pigment-based ink for ballpoint pens according to the present invention has excellent lubricity and less abrasion of the ball receiving seat, so that the ink can be used up to the end. It has excellent properties for

Continuation of the front page (72) Inventor Naoki Sato 2239-1, Kamatamari, Tamari Village, Shinji-gun, Ibaraki Prefecture Pentel Co., Ltd. Ibaraki Plant

Claims (1)

[Claims] 1. A ball-point pen aqueous solution comprising at least titanium oxide, a thickening water-soluble resin, a binder, a water-soluble organic solvent, N-fatty acid acyl-L-glutamate, and water. Pigment ink.