JPH10330672A - Aqueous ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous ink composition not causing the stoppage and decrease of ink extrusion, not generating gas bubbles, excellent in stability with the lapse of time and useful for ball point inks, etc., by including a coloring agent, water, α-tocopherol, and a solubilizing agent for the α-tocopherol in water. SOLUTION: This aqueous ink composition comprises (A) a coloring agent such as an acidic dye or a direct dye preferably in an amount of 0.1-20 wt.% (based on the whole amount of the aqueous ink composition), (B) water such as ion-exchanged water preferably in an amount of 30-95 wt.%, (C) α-tocopherol preferably in an amount of 0.1-3 wt.%, and (D) a solubilizing agent such as an acylsarcosine salt for the component C in water preferably in an amount of 1-20 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous ink composition used for a writing instrument. More specifically, the present invention does not cause the ink to run out during printing, so that the ink can flow out very stably and smoothly. TECHNICAL FIELD The present invention relates to a water-based ink composition that is stable over time in a raw ink type writing implement having a body and without bubbles.

[0002]

2. Description of the Related Art In general, a writing instrument has a capillary as an outflow path of ink. For example, a writing instrument having a pen tip to which a fiber bundle is fixed is a capillary formed between fibers of the pen tip, and a ballpoint pen corresponds to an arrow groove formed in a ballpoint pen tip. By the way, when air bubbles are present in the capillary, the outflow of the ink is remarkably impeded, so that the ink runs out and the ink comes out. There are various possible causes for the presence of air bubbles in the capillary tube, such as entrainment of air when the ink is filled in a writing instrument, or the gas dissolved in the ink, but it is not clear. A writing instrument with a small number of capillaries, such as a ballpoint pen, particularly as a writing instrument, has a large effect on ink bleeding and bleeding due to bubbles in the capillary, and cannot smoothly discharge ink. In order to solve this problem, it has been proposed to use a large amount of a surfactant or to remove bubbles using a water-soluble silicone oil.

[0003] Further, in a raw ink type writing instrument in which an ink cylinder is directly filled with ink and an ink backflow preventive is filled on this ink, the presence of air bubbles in the ink not only impairs the appearance but also causes a high temperature. Underneath, the bubbles expand and the ink is separated, or the ink backflow preventive pops out of the ink cylinder. To solve this problem, it is common practice to put the ink under reduced pressure before assembling the pen or to remove air bubbles by centrifugation after assembling.

[0004]

However, the above surfactants and water-soluble silicone oils have not been able to provide a sufficient effect, and the problem of air bubbles has been completely solved by the decompression method and the centrifugal method at the time of production. Do not mean.

[0005]

The gist of the present invention is to provide an aqueous ink composition containing at least a coloring material, water, α-tocopherol, and a solubilizing agent for α-tocopherol in water. is there.

The details will be described below. As the coloring material, any of dyes and pigments can be used. The dye is an acid dye,
Although any of direct dyes and basic dyes can be used, it is preferable to use acid dyes and direct dyes. An example is given below.

As direct dyes, Japan Direct Black D Conc (CI Direct Black 1)
7), Water Black 100L (19), Water Black L-200 (19), Direct Fast Black B (22), Direct Fast Black AB (32), Direct Deep Black EX (38), Direct Fast Black conch (5
1), Kayaras Spragley VGN (Id. 71), Kayaras Direct Brilliant Yellow G (CI Direct Yellow 4), Direct Fast Yellow 5GL (Id. 2)
6), Aizen Primula Yellow GCLH (44), Direct Fast Yellow R (50), Aizen Direct Fast Red FH (CI Direct Red 1), Nippon Fast Scarlet GSX (4),
Direct Fast Scarlet 4BS (23), Eisen Direct Lodulin BH (31), Direct Scarlet B (37), Kayak Direct Scarlet 3B (39), Aizen Primula Pink 2B
LH (75), Sumilight Red F3B (80),
Aizen Primula Red 4BH (81), Kayalas Sprarubin BL (83), Kayalas Light Red F5
G (225), Kayasu Light Red F5B (22)
6), Kayalas Light Rose FR (227), Direct Sky Blue 6B (CI Direct Blue 1), Direct Sky Blue 5B (15), Sumilight Supra Blue BRR Conch (71), Daibogen Turquoise Blue S (86), Water Blue #
3 (86), Kayara Star Coize Blue GL (8
6), Kayalas Supra Blue FF2GL (106),
Kayasu splatter turquoise blue FBL (199).

Acid dyes include Acid Blue Black 10B (CI Acid Black 1), Nigrosine (2), and Suminol Milling Black 8BX (2).
4), Kayanol milling black VLG (26),
Suminol Fast Black BR Conc (31), Mitsui Nylon Black GL (52), Aizen Opal Black WH Extra Conc (52), Sumilan Black WA (52), Ranyl Black BG Extra Conc (107), Kayanol milling black T
LB (109), Suminol Milling Black B (109), Kayanol Milling Black TLR (11)
0), Eisen Opal Black New Conch (11
9), Water Black 187-L (154), Kayak Acid Brilliant Flavin FF (CI Acid Yellow 7: 1), Kayasil Yellow GG (17),
Xylene Light Yellow 2G 140% (17), Suminol Leveling Yellow NR (19), Daiwa Tartrazine (23), Kayaktor Trazine (23), Suminol Fast Yellow R (25), Diacid Light Yellow 2GP (29), Suminol Milling Yellow O (38), Suminol Milling Yellow MR (4)
2), Water Yellow # 6 (42), Kayanol Yellow NFG (49), Suminol Milling Yellow 3G
(No. 72), Suminol Fast Yellow G (No. 61),
Suminol Milling Yellow G (78), Kyanol Yellow N5G (110), Suminol Milling Yellow 4
G200% (141), Kayanol Yellow NG (1)
35), Kayanol Milling Yellow 5GW (12
7), Kayanol Milling Yellow 6GW (142),
Sumitomo Fast Scarlet A (CI Acid Red 8), Kayak Silk Scarlet (9), Solar Rubin Extra (14), Daiwa New Koksin (18), Eisenbon Saw RH (26), Daiwa Red No. 2 (27), Suminol Leveling Brilliant Red S3B (35), Kayasil Rubinol 3GS
(37), Eisenerythrosin (51), Kayaking Acid Rhodamine FB (52), Suminol Leveling Rubinol 3GP (57), Diacid Alizarin Rubinol F3G 200% (82), Eisen Eosin GH (87) ), Water Pink # 2 (9
2), Eisen Acid Phloxine PB (92), Rose Bengal (94), Kayanol milling scarlet FGW (111), Kayanol milling rubin 3
BW (129), Sumino All Milling Brilliant Red 3BN Conch (131), Suminol Milling Brilliant Red BS (138), Eisen Opal Pink BH (186), Suminol Milling Brilliant Red B Conch (249), Kayak Acid Brilliant Red 3BL (254), Kayak Acid Brilliant Red BL (265), Kayanol Milling Red GW (276), Mitsui Acid Violet 6BN (CI Acid Violet 15), Mitsui Acid Violet BN (No. 17), Sumitomo Patent Pure Blue VX (CI Acid Blue 1), Water Blue # 106 (1), Patent Blue AF (7), Water Blue # 9 (9), Daiwa Blue 1 (1) 9) Supra Nord Blue B (same 1
5), Orient Solble Blue OBC (22), Suminol Leveling Blue 4GL (23), Mitsui Nylon Fast Blue G (25), Kayasil Blue A
GG (40), Kayasil Blue BR (41), Mitsui Alizarin Safirol SE (43), Suminol Leveling Sky Blue R Extra Conc (6)
2), Mitsui Nylon Fast Sky Blue B (7)
8), Sumitomobrilliant indocyanine 6Bh / c
(83), Sandlancyanine N-6B 350% (90), Water Blue # 115 (90), Orient Soluble Blue OBB (93), Sumitomobrilliant Blue 5G (103), Kayanol Milling Ultra Sky SE (112), Kayanol milling cyanine 5R (113), Eisen Opal Blue 2G
LH (158), Daiwa Guinea Green B (CI.
Acid Green 3), Acid Brilliant Milling Green B (9), Daiwa Green # 70 (1)
6), Kayanol Cyanine Green G (25) and Suminol Milling Green G (27).

The basic dyes include C.I. I. Basic Blue 7, C.I. I. Basic Red 1 and the like.

The above dyes can be used alone or as a mixture. The amount of the ink used is 0.1 to the total amount of the aqueous ink.
1-20% by weight is preferred.

The pigment is an azo pigment, a condensed polyazo pigment,
Phthalocyanine pigments, quinacridone pigments, indigo pigments, thioindigo pigments, nitroso pigments, nitro pigments, basic dye pigments, acid dye pigments, vat dye pigments, mordant dye pigments, and natural dye pigments And inorganic pigments such as loess, barium yellow, dark blue, cadmium red, barium sulfate, titanium oxide, red iron oxide, iron black, carbon black and the like.

Among the coloring materials used in raw ink type writing instruments, the fluorescent pigment is obtained by coloring resin particles with a dye. Examples of the resin particles include a copolymer of styrene and acrylonitrile, and a copolymer of acrylic acid. The particle size is preferably 0.05 to 0.3 μm. The dye for coloring the resin particles may be C.I. I.
Disperse dyes such as Desper Yellow 82; I. And oil-soluble dyes such as Solvent Yellow 44. In order to color the resin particles with the dye, the dye is mixed with the monomer at a stage prior to the synthesis of the resin particles, or the dye is mixed during the polymerization, or the dye is mixed after the synthesis. be able to. One example of a commercially available product is Lumicoll NK
W-3002 (green pigment, styrene-acrylonitrile copolymer was obtained from CI Basic Yellow 40 and C.I.
I. Colored in Basic Blue 45), NKW
NKW-3005 (yellow orange pigment, styrene-acrylonitrile copolymer colored with CI Basic Yellow 40, CI Basic Violet 11 and CI Basic Red 1: 1) and NKW-3005 (yellow The pigment, styrene-acrylonitrile copolymer was prepared according to C.I.
Basic Yellow 40), NKW-
3007 (pink pigment, styrene-acrylonitrile copolymer was obtained from CI Basic Violet 11 and C.I.
I. Basic red 1: 1), NK
W-3008 (light blue pigment, styrene-acrylonitrile copolymer colored with CI Basic Blue 45), NKW-3077 (purple pigment, styrene-acrylonitrile copolymer with CI Basic Violet 7 NKW-3602 (green pigment, styrene acrylonitrile copolymer obtained from CI Basic Yellow 40 and CI Basic Blue 45)
NKW-3604 (orange pigment, styrene-acrylonitrile copolymer obtained by CI Basic Yellow 40 and CI Basic Violet 1)
1 and C.I. I. NKW-3605 (yellow pigment, styrene-acrylonitrile copolymer obtained from CI Basic Yellow 4)
0), NKW-3607 (pink pigment,
The styrene-acrylonitrile copolymer was used as a C.I. I. Basic violet 11 and C.I. I. Basic Red 1: 1), NKW-3608 (light blue pigment, styrene-acrylonitrile copolymer colored with CI Basic Blue 45), NKW-36
77 (purple pigment, styrene-acrylonitrile copolymer colored with CI Basic Violet 7)
(Above, manufactured by Nippon Fluorescent Chemical Co., Ltd.), Victoria Orange G-21A (copolymer of orange pigment and acrylic acid is C.I.
I. Basic Yellow 40, C.I. I. Basic Red 1 and C.I. I. Basic violet 11), Victoria Yellow G-20 (yellow pigment, acrylic acid copolymer colored with CI Basic Yellow 40 and CI Desper Yellow 82), Victoria Green G- 24C (a yellow-green pigment and a copolymer of acrylic acid were used as CI Basic Yellow 40, C.I.
I. Desper Yellow 82 and C.I. I. Colored with Basic Green 1), Victoria Pink G-23
(A copolymer of a pink pigment and acrylic acid colored with CI Basic Red 1 and CI Basic Violet 11), Victoria Blue G-25 (a copolymer of a light blue pigment and acrylic acid is C.I. C. I. Basic Blue 3), Victoria Red G-22 (Red pigment, copolymer of acrylic acid with CI Basic Yellow 40, CI Despar Yellow 42, CI Basic Red 1) , CI Basic Violet 1
1 and C.I. I. (Colored with Basic Blue 3)
(The above are manufactured by Mikuni Shigyo Co., Ltd.), Cosmo Color S-100
OF series (manufactured by Toyo Soda Co., Ltd.) and the like.

The above pigments can be used alone or in combination of two or more. The amount used is preferably from 1 to 50% by weight based on the total amount of the aqueous ink. The amount of use is preferably 1% by weight or more to make the density of the handwriting sufficient, and 50% by weight to maintain the ink viscosity appropriately and to make the ink ejection from the application body such as a pen tip good at the time of writing. The following amounts are preferred.

Water is used as a solvent, and usually ion-exchanged water, distilled water or the like is used. The amount used is preferably 30 to 95% based on the total amount of the aqueous ink.

Α-Tocopherol (dl-α-tocopherol, d-α-tocopherol, 1-α-tocopherol, commonly called vitamin E) is generally used as an antioxidant, but the present invention relates to aqueous ink compositions. It is used to prevent the ink from running out of the material and to prevent the ink from sticking out, or to prevent the generation of bubbles in the ink. The amount used for obtaining a sufficient effect on quality is preferably 0.1 to 3% by weight based on the total amount of the aqueous ink composition.

Since the above-mentioned α-tocopherol is insoluble in water as it is, a solubilizing agent for water is required. Suitable solubilizing agents are anionic surfactants, for example, acyl sarcosine salts, polyoxyethylene alkyl ether acetates, polyoxyethylene alkyl ether sulfates, polyoxyethylene alkyl ether phosphates, alkylbenzene sulfonates , Α-
Examples include olefin sulfonates, polyoxyethylene alkyl sulfosuccinates, and various fatty acid salts. The used amount may be an amount capable of dissolving α-tocopherol, and is preferably 1 to 20% by weight based on the total amount of the aqueous ink.

In addition to the above essential components, if necessary, glycol solvents such as ethylene glycol, diethylene glycol, triethylene glycol and propylene glycol, known solvents such as glycerin and sorbitan, polysaccharides, urea, ethylene urea and the like Various additives such as known wetting agents, preservatives, fungicides, rust inhibitors, alkalis, fragrances, defoamers, gloss-imparting agents, dyes for complementary colors, and water-soluble natural high molecular substances Additives such as water-soluble synthetic high molecular substances can be used singly or in combination depending on the purpose and need.

In order to obtain the aqueous ink composition of the present invention, a conventionally known method can be used. When using a dye as a coloring material, each component is stirred and mixed using a stirrer,
When a pigment is used, each component is dispersed and mixed using a disperser.

[0019]

The compound used in the aqueous ink composition according to the present invention removes air bubbles in the ink and air bubbles present in the arrow groove of the ballpoint pen (outflow path of the ink) and smoothes the ink discharge. Although the mechanism is not clear, it is presumed that these compounds absorb oxygen in the bubbles and dissolve the bubbles in the ink.

[0020]

The present invention will be described in more detail with reference to the following examples. Example 1 Lumicoll NKW3004 (fluorescent pigment, manufactured by Nippon Fluorescence Co., Ltd.) 35.0 parts by weight Sorbitan 18.0 parts by weight Sodium oleoylsarcosine 3.0 parts by weight dl-α-tocopherol 0.5 parts by weight Water 43.5 Parts by weight The above components were blended and stirred with a stirrer for 2 hours to obtain an orange aqueous ink composition.

Example 2 Lumicoll NKW3005 (fluorescent pigment, manufactured by Nippon Fluorescent Co., Ltd.) 20.0 parts by weight Glycerin 15.0 parts by weight Polyoxyethylene (3 mol addition) sodium tridecyl ether acetate 5.0 parts by weight dl- 1.0 part by weight of α-tocopherol 59.0 parts by weight of water The above components were mixed and stirred with a stirrer for 2 hours to obtain a yellow aqueous ink composition.

Example 3 Victoria Pink G-23 (Fluorescent Pigment, manufactured by Mikuni Color Co., Ltd.) 45.0 parts by weight Glycerin 10.0 parts by weight Sodium lauryl sulfate 8.0 parts by weight d-α-tocopherol 2.0 parts by weight Part water 35.0 parts by weight The above components were mixed and stirred with a stirrer for 2 hours to obtain a pink aqueous ink composition.

Example 4 12.0 parts by weight of Lumicoll NKW3608 (fluorescent pigment, manufactured by Mikuni Pigment Co., Ltd.) I. Acid Blue 9 0.1 parts by weight Glycerin 10.0 parts by weight Polyoxyethylene (3 mol addition) sodium tridecyl ether acetate 5.0 parts by weight dl-α-tocopherol 0.5 parts by weight Water 72.4 parts by weight Each of the above The components were blended and stirred with a stirrer for 2 hours to obtain a sky blue aqueous ink composition.

Example 5 C.I. I. Acid Orange 56 10.0 parts by weight Propylene glycol 10.0 parts by weight Ethylene glycol 10.0 parts by weight Polyoxyethylene (3 mole addition) sodium tridecyl ether acetate 5.0 parts by weight dl-α-tocopherol 1.0 parts by weight Water 64.0 parts by weight The above components were mixed and stirred with a stirrer for 2 hours to obtain an orange aqueous ink composition.

Example 6 C.I. I. Acid Violet 17 5.0 parts by weight Ethylene glycol 20.0 parts by weight Oleoyl sarcosine sodium 5.0 parts by weight dl-α-tocopherol 0.3 parts by weight Water 69.7 parts by weight After stirring for an hour, a purple aqueous ink composition was obtained.

Example 7 C.I. I. Acid Violet 49 6.0 parts by weight C.I. I. Acid Blue 9 7.0 parts by weight Ethylene glycol 15.0 parts by weight Propylene glycol 5.0 parts by weight Polyoxyethylene (3 mol addition) sodium tridecyl ether acetate 8.0 parts by weight dl-α-tocopherol 1.5 parts by weight 57.5 parts by weight of water The above components were blended and stirred with a stirrer for 2 hours to obtain a purple aqueous ink composition.

Example 8 Carbon black 10.0 parts by weight Glycerin 10.0 parts by weight Ethylene glycol 10.0 parts by weight Styrene-ammonium acrylate (dispersant) 10.0 parts by weight Sodium oleoyl sarcosine 5.0 parts by weight dl -Α-Tocopherol 0.5 parts by weight Water 54.5 parts by weight The above components were dispersed in a ball mill for 24 hours to obtain a black aqueous ink composition.

Comparative Example 1 An aqueous ink composition was obtained in the same manner as in Example 1 except that dl-α-tocopherol was used and water was used instead.

Comparative Example 2 An aqueous ink composition was obtained in the same manner as in Example 2 except that dl-α-tocopherol was used and water was used instead.

Comparative Example 3 In the same manner as in Example 3, except that d-α-tocopherol was used in place of silicon KM-73 (a water-soluble silicone oil manufactured by Shin-Etsu Chemical Co., Ltd.). Thus, an aqueous ink composition was obtained.

Comparative Example 4 An aqueous ink composition was obtained in the same manner as in Example 5, except that dl-α-tocopherol was used and water was used instead.

Comparative Example 5 An aqueous ink composition was obtained in the same manner as in Example 6, except that dl-α-tocopherol was used and water was used instead.

Comparative Example 6 In Example 7, dl-α-tocopherol and POE
(3) An aqueous ink composition was obtained in the same manner as in Example 7, except that water was used instead of sodium tridecyl ether acetate.

As described above, Examples 1-4 and Comparative Examples 1-3
Was stirred for 1 hour while heating each component to 30 ° C. to obtain an aqueous ink composition. Examples 5 to 8 and Comparative Examples 4 to 6
Was dispersed for 1 hour with a dispersing machine to obtain an ink composition.

The ink compositions obtained in Examples 1 to 8 and Comparative Examples 1 to 6 were tested. Table 1 shows the results
And Table 2.

Bubble generation confirmation test: (Preparation of test sample) A transparent ink container made of a hollow cylinder made of polypropylene (inner diameter of 3.0 mm) with a ball point pen tip having a ball diameter of 0.5 mm connected to one end. 0.8 g of the aqueous ink composition obtained in each of Examples 1 to 4 and Comparative Examples 1 to 3 was filled, and 0.1 g of the ink backflow preventer was filled in the upper part. Was added to remove air bubbles in the ink to prepare a test ballpoint pen. (Aging test at 50 ° C.)
Leave for 3 days, 1 week and 3 months with the pen point downward in a constant temperature room. (Confirmation of bubble generation) Method: Immediately after preparing the above test ballpoint pen, visually check if there are bubbles between the ink when the pen tip is turned down and the ink backflow preventer, and store under the above conditions. After that, the presence or absence of air bubbles was visually confirmed by the same method. (Evaluation) ：: No bubbles were observed. X: The presence of air bubbles is confirmed. XX: Bubbles are separating the ink and the backflow preventive, or the backflow preventive is protruding from the ink storage tube.

Blurring test: (Preparation of test sample) Examples 5 to 8 and Comparative Examples 4 to 6
The ball-point pen (ball Pentel B50, Pentel Co., Ltd.) using a commercially available batting-type water-based ink is used for the aqueous ink composition obtained in
2.0 g) is filled in the same writing implement as that described in (1) above, and writing is performed upward on high-quality paper to cause ink to run out. (Elapsed Test at 50 ° C.) Conditions: The test ballpoint pen is allowed to stand for 3 days, 1 week, and 3 months in a 50 ° C. constant temperature room with the pen tip facing upward. (Confirmation of handwriting) Method: Immediately after the test ballpoint pen was prepared, the writing state was checked. After storage under the above conditions, the writing state was checked in the same manner as immediately after the preparation. Note that the writing must be made of high quality paper (JIS
Using P3201 writing paper A), handwriting was written with ♀♀♀. (Evaluation) ：: Good handwriting was obtained. X: Insufficiency of ink and blurring (ink bleeding) occurred.

[0038]

[Table 1]

[0039]

[Table 2]

As described in detail above, the water-based ink composition of the present invention has excellent characteristics in which the ink is not cut off or the ink comes out, the outflow of the ink is stable and smooth, and no bubbles are generated. It is a water-based ink composition.

Claims (1)

[Claims] 1. An aqueous ink composition comprising at least a coloring material, water, α-tocopherol, and a solubilizing agent for α-tocopherol in water.