O / w type emulsion ink composition for ballpoint pen

Abstract

To provide an O / W type emulsion ink for a ballpoint pen, which can obtain a marble type handwriting from the start of writing and can enjoy evenly from the start of writing to the end of writing without causing color deviation, in a ballpoint pen applied with high shearing force when the ink is discharged.SOLUTION: An O / W type emulsion ink composition for a ballpoint pen contains: a water phase component containing at least water and a colorant; an oil phase component containing at least an organic solvent having a solubility of 5 g or less in 100 g of water at 20°C, and a colorant; and a (acrylate / acrylic acid alkyl (C10-30)) cross polymer. The oil phase component is emulsified and diffused in the water phase component.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an O / W type emulsion ink composition for ballpoint pens. [Background technology]

[0002] Conventionally, there are ballpoint pens known that provide marbled handwriting, such as handwriting that forms a marbled pattern of multiple colors or handwriting that changes color during writing. In these ballpoint pens, multiple inks of different colors are filled in the ink tank without randomly mixing with each other. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-206118 A Summary of the Invention [Problem to be solved by the invention]

[0004] These ballpoint pens can be filled with multiple colors of ink, allowing you to enjoy a variety of color changes. However, when the ink is discharged, it is subject to high shear caused by the rotation of the ball, which can cause inks with similar compositions to mix together in the tip of the ballpoint pen and be discharged as one color. Also, due to color bias in the ink tank or tip, it can be difficult to notice a color change after just a short stroke. [Means for solving the problem]

[0005] The present invention relates to an O / W type emulsion ink composition for ballpoint pens, which contains at least an aqueous phase component containing at least water and a colorant, an oil phase component containing at least an organic solvent having a solubility of 5 g or less in 100 g of water at 20° C. and a colorant, and an (acrylates / C10-30 alkyl acrylate) crosspolymer, wherein the oil phase component is emulsified and dispersed in the aqueous phase component. Effect of the Invention

[0006] According to at least one embodiment of the present invention, there is provided an O / W type emulsion ink composition for a ballpoint pen, which is subjected to high shear when ejected, and which can produce marbled handwriting from the beginning of writing, without color bias from the beginning to the end of writing, allowing the user to enjoy the same writing experience. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] The coloring agent used in the water phase component of the O / W type emulsion ink composition of the present invention is a dye or pigment that imparts a coloring effect to handwriting and makes it visible. Specific examples of the dye that can be used include acid dyes, direct dyes, basic dyes, etc. Some examples include Japanol Fast Black D Concentrate (CI Direct Black 17), 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 Concentrate (51), Kayalas Spragray VGN (71), Kayalas Direct Brilliant Yellow G (CI Direct Yellow 4), Direct Fast Yellow 5GL (26), Aizen Primula Yellow GCLH (44), Direct Fast Yellow R (50), Daiwa IJ Yellow 306H (123), Aizen Direct Fast Red FH (CI Direct Red 1), Nippon Fast Scarlet GSX (4), Direct Fast Scarlet 4BS (23), Aizen Dai Lectrodurine BH (same 31), Direct Scarlet B (same 37), Kayak Direct Scarlet 3B (same 39), Aizen Primula Pink 2 BLH (same 75), Sumi Light Red F3B (same 80), Aizen Primula Red 4 BH (same 81), Kayalas Spralubin BL (same 83), Kayalas Light Red F5G (same 225), Kayalas Light Red F5B (same 226), Kayalas Light Rose FR (same 227), Dai Direct dyes such as Rect Sky Blue 6B (CI Direct Blue 1), Direct Sky Blue 5B (CI Direct Blue 15), Sumilite Splat Blue BRR Conc (CI Direct Blue 71), Daibogen Turquoise Blue S (CI Direct Blue 86), Kayalas Turquoise Blue GL (CI Direct Blue 86), Water Blue #3 (CI Direct Blue 87), Kayalas Splat Blue FF2GL (CI Direct Blue 106), Kayalas Splat Turquoise Blue FBL (CI Direct Blue 199), and Acid Blue Black 10B (CI Direct Blue 10B).Acid Black 1), Nigrosine (same 2), Suminol Milling Black 8BX (same 24), Kayanol Milling Black VLG (same 26), Suminol Fast Black BR ​​Conc (same 31), Mitsui Nylon Black GL (same 52), Aizen Opal Black WH Extra Conc (same 52), Sumiran Black WA (same 52), Ranil Black BG Extra Conc (same 107), Kayanol Milling Black TLB (same 109), Suminol Milling Black B (same 109), Kayanol Milling Black TLR (same 110), Aizen Opal Black New Conc (same 119), Water Black 187-L (same 154), Water Black #256L, Kayaku Acid Brilliant Flavin FF (CI Acid Yellow 7:1), Kayasil Yellow GG (same 17), Xylene Light Yellow 2G 140% (same 17) , Suminol Leveling Yellow NR (same 19), Daiwa Tatrazin (same 23), Kayak Tatrazin (same 23), Water Yellow #1 (same 23), Suminol Fast Yellow R (same 25), Diacid Light Yellow 2GP (same 29), Suminol Milling Yellow O (same 38), Suminol Milling Yellow MR (same 42), Water Yellow #6C (same 42), Kayanol Yellow NFG (same 49) , Suminol Milling Yellow 3G (same 72), Suminol Fast Yellow G (same 61), Suminol Milling Yellow G (same 78), Kayanol Yellow N 5G (same 110), Suminol Milling Yellow 4G 200% (same 141), Kayanol Yellow NG (same 135), Kayanol Milling Yellow 5GW (same 127), Kayanol Milling Yellow 6GW (same 142), Sumitomo Fast Scarlet A (CIAcid Red 8), Kayaku Silk Scarlet (same 9), Solar Rubin Extra (same 14), Daiwa New Kokushin (same 18), Aizen Bonso RH (same 26), Daiwa Red No. 2 (same 27), Suminol Leveling Brilliant Red S3B (same 35), Kayashi Rubinol 3GS (same 37), Aizen Erythrosine (same 51), Kayaku Acid Rhodamine FB (same 52), Daiwa Red No. 106 WB (same 52), Suminol Leveling Rubinol 3GP (same 57), Diacid Alizarin Rubinol F3G 200% (same 82), Aizen Eosin GH (same 87), Daiwa Red No. 103 WB (same 87), Daiwa Red No. 104 WB (same 92), Water Pink #2 (same 92), Aizen Acid Floki Shin PB (92), Rose Bengal (94), Kayanol Milling Scarlet FGW (111), Kayanol Milling Rubin 3BW (129), Suminol Milling Brilliant Red 3BN Concentrate (131), Suminol Milling Brilliant Red BS (138), Aizen Opal Pink BH (186), Suminol Milling Brilliant Red B Concentrate (249), Kayaku Acid Brilliant Red 3BL (254), Kayaku Acid Brilliant Red BL (265), Kayanol Milling Red GW (276), Mitsui Acid Violet 6BN (CI Acid Violet 15), Mitsui Acid Violet BN (17), Sumitomo Patent Pure Blue VX (CIAcid Blue 1), Water Blue #106 (same 1), Patent Blue AF (same 7), Water Blue #9 (same 9), Daiwa Blue No. 1 (same 9), Water Blue #116 (same 15), Supranol Blue B (same 15), Orient Soluble Blue OBC (same 22), Suminol Leveling Blue 4GL (same 23), Mitsui Nylon Fast Blue G (same 25), Kayasil Blue AGG (same 40), Kayasil Blue BR (same 41), Mitsui Alizarin Sapphirol SE (same 43), Suminol Leveling Sky Blue R Extra Conc ( 62), Mitsui Nylon Fast Sky Blue B (78), Sumitomo Brilliant Indocyanine 6Bh / c (83), Sandran Cyanine N-6B350% (90), Water Blue #105S (90), Fisco Blue 664 (90), Orient Soluble Blue OBX (93), Orient Soluble Blue OBB (93), Sumitomo Brilliant Blue 5G (103), Kayanol Milling Ultra Sky SE (112), Kayanol Milling Cyanine 5R (113), Aizen Opal Blue 2GLH (1 58), Water Blue #119, Daiwa Guinea Green B (CI Acid Green 3), Acid Brilliant Milling Green B (CI 9), Daiwa Green #70 (CI 16), Kayanol Cyanine Green G (CI 25), Suminol Milling Green G (CI 27) and other acid dyes, Eisen Katilon Yellow 3GLH (CI Basic Yellow 11), Eisen Katilon Brilliant Yellow 5GLH (CI 13), Sumiacrylic Yellow E-3RD (CI 15), Maxillon Yellow 2RL (CI 19), Astrazon Yellow 7GLL (CI 2 1), Kayakryl Golden Yellow GL-ED (same 28), Astrazon Yellow 5 GL (same 51), Aizen Katiron Orange GLH (CI Basic Orange 21), Aizen Katiron Brown 3 GLH (same 30), Rhodamine 6 GCP (CI Basic Red 1), Aizen Astraphloxine (same 12), Sumiacryl Brilliant Red E-2B (same 15), Astrazon Red GTL (same 18), Aizen Katiron Brilliant Pink BGH (same 27), Maxillon Red GRL (same 46), Aizen Methyl Violet (CIBasic Violet 1), Aizen Crystal Violet (3), Aizen Rhodamine B (10), Astrazon Blue G (CI Basic Blue 1), Astrazon Blue BG (3), Water Blue #10C (7), Methylene Blue (9), Maxilon Blue GRL (41), Aizen Katilon Blue BRLH (54), Aizen Diamond Green GH (CI Basic Green 1), Aizen Malachite Green (4), Bismarck Brown G (CI Basic Brown 1), and other basic dyes.

[0008] Specific examples of pigments include organic pigments such as azo pigments, nitroso pigments, nitro pigments, basic dye pigments, acid dye pigments, vapour dye pigments, mordant dye pigments, and natural dye pigments; inorganic pigments such as ocher, barium yellow, ultramarine, Prussian blue, cadmium red, barium sulfate, titanium oxide, red iron oxide, iron black, and carbon black; metal powder pigments such as aluminum powder, gold powder, silver powder, copper powder, tin powder, and brass powder; fluorescent pigments; and mica pigments. Specific examples of carbon black include Mitsubishi Carbon Black #10B, #20B, #14, #25, #30, #33, #40, #44, #45, #45L, #50, #55, #95, #260, #900, #1000, #2200B, #2300, #2350, #2400B, #2650, #2700, #4000B, CF9, MA8, MA11, MA77, MA100, MA220, MA230, MA600 and MCF88 (all manufactured by Mitsubishi Chemical Corporation), Monarch 120, Monarch 700, Monarch 800, Monarch 880, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400, Mogul L, Regal 99R, Regal 250R, Regal 300R, Regal 330R, Regal 400R, Regal 500 and Regal 660R (all manufactured by Cabot Corporation). Corporation, USA), Printex A, Printex G, Printex U, Printex V, Printex 55, Printex 140U, Printex 140V, Printex 35, Printex 40, Printex 45, PrintexPrintex 85, Ninepex 35, Special Black 4, Special Black 4A, Special Black 5, Special Black 6, Special Black 100, Special Black 250, Special Black 350, Special Black 550, Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color Black S150, Color Black S160 and Color Black S170 (all manufactured by Degussa Japan Co., Ltd.), Raven 5000 Ultra II, Raven 2500 Ultra, Raven 1250, Raven 760 Ultra (all manufactured by Degussa Japan Co., Ltd.),Colombian Carbon Japan Co., Ltd.), CI Pigment Black 7, etc. Specific examples of organic pigments include CI Pigment Red 170, CI Pigment 213, CI Pigment Orange 38, CI Pigment Blue 15, CI Pigment Violet 23, Aniline Black (CI50440), Cyanine Black, Naphthol Yellow S (CI10316), Hansa Yellow 10G (CI11710), Hansa Yellow 5G (CI11660), Hansa Yellow 3G (CI11670), Hansa Yellow G (CI11680), Hansa Yellow GR (CI11690), Hansa Yellow GR (CI11691), Hansa Yellow GR (CI11692), Hansa Yellow GR (CI11693), Hansa Yellow GR (CI11694), Hansa Yellow GR (CI11695), Hansa Yellow GR (CI11696), Hansa Yellow GR (CI11697), Hansa Yellow GR (CI11698), Hansa Yellow GR (CI11699), Hansa Yellow GR (CI11699), Hansa Yellow GR (CI11691), Hansa Yellow GR (CI11692), Hansa Yellow GR (CI11694), Hansa Yellow GR (CI11695), Hansa Yellow GR (CI11696), Hansa Yellow GR (CI11697), Hansa Yellow GR (CI11698), Hansa Yellow GR (CI1169 ...0), Hansa Yellow I11730), Hansa Yellow A (CI11735), Hansa Yellow RN (CI11740), Hansa Yellow R (CI12710), Pigment Yellow L (CI12720), Benzidine Yellow (CI21090), Benzidine Yellow G (CI21095), Benzidine Yellow GR (CI21100), Permanent Yellow NCG (CI20040), Balkan Fast Yellow 5G (CI21220), Balkan Fast Yellow R (CI21135), Tart Radic Lake (CI19140), Quinoline Yellow Lake (CI47005), Anthragen Yellow 6GL (CI60520), Permanent Yellow FGL, Permanent Yellow H10G, Permanent Yellow HR, Anthrapyrimidine Yellow (CI68420), Sudan I (CI12055), Permanent Orange (CI12075), Lithol Fast Orange (CI12125), Permanent Orange GTR (CI12305), Hansa Yellow 3R (CI 11725), Balkan Fast Orange GG (CI21165), Benzidine Orange G (CI21110), Persian Orange (CI15510), Indanthrene Brilliant Orange GK (CI59305), Indanthrene Brilliant Orange RK (CI59105), Indanthrene Brilliant Orange GR (CI71105), Permanent Brown FG (CI12480), Para Brown (CI12071), Permanent Red 4R (CI12120),Para Red (CI12070), Fire Red (CI12085), Parachlor Orthoaniline Red (CI12090), Lithol Fast Scarlet, Brilliant Fast Scarlet (CI12315), Brilliant Carmine BS, Permanent Red F2R (CI12310), Permanent Red F4R (CI12335), Permanent Red FRL (CI12440), Permanent Red FRLL (CI12460), Permanent Red F4RH (CI12420), Fast S Carlet VD, Balkan Fast Rubin B (CI12320), Balkan Fast Pink G (CI12330), Light Fast Red Toner B (CI12450), Light Fast Red Toner R (CI12455), Permanent Carmine FB (CI12490), Pyrazolone Red (CI12120), Lysol Red (CI15630), Lake Red C (CI15585), Lake Red D (CI15500), Anthocine B (CI18030), Brilliant Scarlet G (CI1580) 0), Lysol Rubin GK (CI15825), Permanent Red F5R (CI15865), Brilliant Carmine 6B (CI15850), Pigment Scarlet 3B (CI16105), Bordeaux 5B (CI12170), Toluidine Maroon (CI12350), Permanent Bordeaux F2R (CI12385), Helio Bordeaux BL (CI14830), Bordeaux 10B (CI15880), Bon Maroon Light (CI15825), Bon Maroon Medium (CI15880), Eosin Lake (CI45380), Rhodamine Lake B (CI45170), Rhodamine Lake Y (CI45160), Alizarin Lake (CI58000), Thioindigo Red B (CI73300), Thioindigo Maroon (CI73385), Permanent Red FGR (CI12370), PV Carmine HR, Watching Red, Monolight Fast Red YS (CI59300), Permanent Red BL, Fast Violet B, Methyl Violet Lake (CI42535), Dioxazine Violet,Alkaline Blue Lake (CI42750A, CI42770A), Peacock Blue Lake (CI42090), Peacock Blue Lake (CI42025), Victoria Blue Lake (CI44045), Phthalocyanine Blue (CI74160), Fast Sky Blue (CI74180), Indanthrene Blue RS (CI69800), Indanthrene Blue BC (CI69825), Indigo (CI73000), Pigment Green B (CI10006), Naphthol Green B (CI10020), Green Gold (CI12775), Acid Green Lake, Malachite Green Lake (CI42000), Phthalocyanine Green, etc. are included, and these are used by dispersing them in a liquid medium.

[0009] When a pigment is used as the colorant, a dispersant may be used to stably disperse the pigment. As the dispersant, a water-soluble resin or a water-soluble resin that has been conventionally used, or an anionic or nonionic surfactant that is used as a dispersant for pigments, can be used. As an example, the polymer dispersant includes anionic polymers such as lignin sulfonate and shellac, polyacrylate, salt of styrene-acrylic acid copolymer, salt of vinylnaphthalene-maleic acid copolymer, sodium salt of β-naphthalenesulfonic acid formalin condensate, phosphate, and nonionic polymers such as polyvinyl alcohol and polyethylene glycol. In addition, as the surfactant, anionic surfactants such as alkyl sulfate, polyoxyethylene alkyl ether sulfate, N-acyl amino acid and its salt, N-acyl methyl taurine salt, polyoxyethylene alkyl ether acetate, alkyl sulfocarboxylate, α-olefin sulfonate, alkyl phosphate, polyoxyethylene alkyl ether phosphate, and nonionic surfactants such as polyoxyethylene alkyl ether, sorbitan alkyl ester, and polyoxyethylene sorbitan alkyl ester can be used. These water-soluble resins and surfactants may be used alone or in combination of two or more thereof. The amount of the surfactants used is preferably 0.05% by weight or more and 20.0% by weight or less relative to 10.0% by weight of the pigment.

[0010] Commercially available water-dispersible pigments are preferably used because they are easier to handle and improve productivity. Specific examples of water-dispersible pigments include Fuji SP Black 8031, 8119, 8167, 8276, 8381, 8406, Fuji SP Red 5096, 5111, 5193, 5220, Fuji SP Bordeaux 5500, Fuji SP Blue 6062, 6133, 6134, 6401, Fuji SP Green 7051, Fuji SP Yellow 4060, 4178, Fuji SP Violet 9011, FujiSP Pink 9524, 9527, Fuji SP Orange 534, FUJI SP Brown 3074, FUJI SP RED 5543, 5544 (all manufactured by Fuji Pigment Co., Ltd.), Emacol Black CN, Emacol Blue FBB, FB, KR, and Emacol Green. LXB, Emacol Violet BL, Emacol Brown3101, Emacol Carmmine FB, Emacol RedBS, Emacol Orange R, Emacol Yellow FD, IRN, 3601, FGN, GN, GG, F5G, F7G, 10GN, 10G, Sandye Super Black K, C, Sandye Super Grey B, Sandye Super BrownSB, FRL, RR, Sandye Super Green L5G, GXB, Sandye Super Navy Blue HRL, GLL, HB, FBL-H, FBL-160, FBB, Sandye Super Violet BL H / C, BL, Sandye Super Bordeaux FR, Sandye Super Pink FBL, F5B, Sandye Super Rubine FR, Sandye superCarmmine FB, Sandye Super Red FFG, RR, BS, 1315, Sandye Super Orange FL, R, BO, Sandye Gold Yellow 5GR, R, 3R, Sandye YellowGG, F3R, IRC, FGN, GN, GRS, GSR-130, GSN-130, GSN, 10GN (all manufactured by Sanyo Pigment Co., Ltd.), Rio Fast Black Fx 8012, 8313, 8169, Rio Fast Red Fx 8209, 8172, Rio Fast Red S Fx 8315, 8316, Rio Fast Blue Fx 8170, Rio Fast Blue FX 8170, Rio Fast Blue S Fx 8312, Rio Fast Green S Fx 8314, EM green G, (all manufactured by Toyo Ink Co., Ltd.), NKW-2101, 2102, 2103, 2104, 2105, 2106, 2107, 2108, 2117, 2127, 2137, 2167, 2101P, 2102P, 2103P, 2104P, 2105P, 2106P, 2107P, 2108P, 2117P, 2127P, 2137P, 2167P, NKW-3002, 3003, 3004, 300 5, 3007, 3077, 3008, 3402, 3404, 3405, 3407, 3408, 3477, 3602, 3603, 3604, 3605, 3607, 3677, 3608, 3702, 3703, 3704, 3705, 3777, 3708, 6013, 6038, 6559 (all manufactured by Nippon Fluorescent Co., Ltd.), Cosmo Color S1000F Series (manufactured by Toyo Soda Co., Ltd.), Victoria Yellow Examples of the dyes and pigments include G-11, G-20, Victoria Orange G-16, G-21, Victoria Red G-19, G-22, Victoria Pink G-17, G-23, Victoria Green G-18, G-24, Victoria Blue G-15, and G-25 (all manufactured by Mikuni Color Co., Ltd.), and the Pollux series, such as Pollux PC5T1020, Pollux Black PC8T135, and Pollux Red IT1030 (all manufactured by Sumika Color Co., Ltd.). The above dyes and pigments can be used alone or in combination.

[0011] Water is used as an essential component of the water phase of the O / W emulsion ink composition, and it is preferable to use ion-exchanged water or purified water. Furthermore, it is possible to add a conventionally known organic solvent to the aqueous phase for the purpose of improving various qualities of the ink, for example, preventing the ink from freezing at low temperatures and preventing the ink from drying at the pen tip. Specific examples of the organic solvent include glycols such as ethylene glycol, diethylene glycol, triethylene glycol, hexylene glycol, 1,2-propanediol, 1,3-butanediol, 2-ethyl 1,3-hexane glycol, propylene glycol, polypropylene glycol, dipropylene glycol, polyethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, thiodiethylene glycol, glycerin, diglycerin, benzyl glycol, and benzyl diglycol; ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, and diethylene glycol monoethyl ether. Examples of suitable solvents include glycol ethers such as ethylene glycol monoisopropyl ether, dipropylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, and tripropylene glycol monophenyl ether; alcohol-based solvents such as ethanol, 1-propanol, 2-propanol, butyl alcohol, isopropyl alcohol, 3-methyl-3-methoxy-1-butanol, α-methylbenzyl alcohol, lauryl alcohol, tridecyl alcohol, isododecyl alcohol, and isotridecyl alcohol; and propylene glycol methyl ether acetate, propylene glycol diacetate, 2-pyrrolidone, N-methyl-2-pyrrolidone, sulfolane, and γ-butyrolactone. These solvents can be used alone or in combination of two or more. The amount of the solvent used is preferably 2.0% by weight or more and 50.0% by weight or less based on the total amount of the ink. If the amount is 2.0% by weight or more and 50.0% by weight or less, the effect of preventing the pen tip from drying out is easily obtained, which is preferable. The amount of water used in the present invention is preferably 30% by weight or more based on the total amount of the ink composition.

[0012] The coloring agent used in the oil phase component of the present invention is preferably an oil-soluble dye. Any known oil-soluble dye can be used without any particular limitation. Specific examples of oil-soluble dyes that can be used include acid dyes, basic dyes, metal complex dyes, salt-forming dyes, azine dyes, anthraquinone dyes, phthalocyanine dyes, and triphenylmethane dyes. Specific examples include Nigrosine Base EE, Nigrosine Base EEL, Nigrosine Base EX, Nigrosine Base EXBP, Nigrosine Base EB, Oil Yellow 101, Nigrosine Base 107, Oil Pink 314, Oil Brown BB, Nigrosine Base GR, Oil Green BG, Oil Blue 613, Oil Scarlet 308, Nigrosine Base BOS, Oil Black HBB, Nigrosine Base 860, Nigrosine Base BS, Varifast Yellow 1101, Nigrosine Base 1105, Nigrosine Base 1109, Nigrosine Base 1120, Nigrosine Base 3104, Nigrosine Base 3105, Nigrosine Base 3108, Nigrosine Base 4120, Nigrosine Base AUM, Varifast Orange 2210, Nigrosine Base 3209, Nigrosine Base 3210, Varifast Red 1306, Nigrosine Base 1308, Nigrosine Base 1320, Nigrosine Base 1364, Nigrosine Base 1355 , 1360, 2303, 2320, 3304, 3306, 3320, Balifast Pink 2310N, Balifast Brown 2402, 3405, Balifast Green 1501, Balifast Blue 1603, 1605, 1607, 1631, 2606, 2610, 2620, Balifast Violet 1701, 1702, 1731, Balifast Striker Black 1802, 1805, 1807, 3804, 3806, 3808, 3810, 3820, 3830, Spirit Red 102, Spirit Black AB, Ospi Yellow RY, ROB-B, MVB3, SP Blue 105 (all manufactured by Orient Chemical Industry Co., Ltd.), Aizen Spiron Yellow 3RH, GRLH Special, C-2GH, C-GNH new, Aizen Spiron Orange 2RH, GRH Concentrate Special, Aizen Spiron Red GEH, BEH, GRLH Special, C-GH, C-BH, Aizen Spiron Violet RH, C-RH, Aizen Spiron Brown BH Concentrate, RH, Aizen Spiron Mahogany RH, Aizen Spiron Blue GNH, 2BNH, C-RH, BPNH, Aizen Spiron Green C-GH, 3GNH Special, Aizen Spiron Black BNH, MH, RLH, GMH Special, BH Special, SBN Orange 703, SBN Violet 510, 521, SPT Orange 6, SPTBlue 111, SOT Pink 1, SOT Blue 4, SOT Black 1, SOT 6, SOT 10, SOT 12, SOT 13 Liquid, Eisen Rhodamine B Base, Eisen Methyl Violet Base, Eisen Victoria Blue B Base (all manufactured by Hodogaya Chemical Co., Ltd.), Oil Yellow CH, Oil Pink 330, Oil Blue 8B, Oil Black S, FS Special A, 2020, 109, 215, AL Yellow 1106D, 31 01, AL Red 2308, Neo Super Yellow C-131, C-132, C-134, Neo Super Orange C-233, Neo Super Red C-431, Neo Super Blue C-555, Neo Super Brown C-732, C-733 (all manufactured by Chuo Synthetic Chemical Industry Co., Ltd.), Oleosol Fast Yellow 2G, Oleosol Fast Orange GL, Oleosol Fast Red BL, Oleosol Fast RL (all manufactured by Taoka Chemical Industry Co., Ltd.) Sanovinyl Yellow 2GLS, Sanovinyl RLS, Sanovinyl 2RLS, Sanovinyl Orange RLS, Sanovinyl Fire Red GLS, Sanovinyl Red 3BLS, Sanovinyl Pink 6BLS, Sanovinyl Blue RN, Sanovinyl GLS, Sanovinyl Green 2GLS, Sanovinyl Brown GLS (all manufactured by Sandoz, Switzerland), Magenta SP 247%, Crystal Violet 10B 250%, Malachite Green Crystal Conch, Brilliant Green Crystal H 90%, Spirit Soluble Red 64843 (all manufactured by Holliday, UK), Neptune Red Base 543, Neptune Blue Base 634, Neptune Violet Base 604, Bassonyl Red 540, Bassonyl Violet 600, Victoria Blue F4R, Nigrosine Base LK (all manufactured by BASF, Germany), Methyl Violet 2B Base (all manufactured by National Anilne Div., USA). These may be used alone or in combination.

[0013] The solvent that can be used for the oil phase component of the O / W type emulsion ink composition of the present invention is an organic solvent that has been used in conventional oil-based ballpoint pens, can dissolve oil-soluble dyes, and has a solubility of 5 g or less in 100 g of water at 20° C. For example, ethylene glycol monoether-based solvents such as ethylene glycol monohexyl ether, ethylene glycol mono 2-ethylhexyl ether, ethylene glycol monophenyl ether, and ethylene glycol monobenzyl ether, diethylene glycol monoether-based solvents such as diethylene glycol monohexyl ether, diethylene glycol mono 2-ethylhexyl ether, and diethylene glycol monophenyl ether, propylene glycol monoether-based solvents such as propylene glycol monophenyl ether, dipropylene glycol mono normal propyl ether, dipropylene glycol monobutyl ether, and tripropylene glycol monobutyl ether, and alcohol-based solvents such as benzyl alcohol and β-phenylethyl alcohol can be used. These solvents may be used alone or in combination of two or more.

[0014] In addition to the above-mentioned main solvent, the oil phase component of the O / W emulsion ink composition may contain any auxiliary solvent. For example, a solvent selected from alcohol, polyhydric alcohol, polyhydric alcohol derivatives such as glycol ether, hydrocarbons, ester solvents, and ether solvents may be used. Solvents with low solubility in water are preferred because they tend to stabilize the emulsion. Solvents with high solubility in oil-based dyes are preferred because they allow the dye to continue to dissolve stably. The auxiliary solvent is preferably within about 10% by weight of the total solvent in the oil phase component.

[0015] The (acrylates / C10-30 alkyl acrylate) crosspolymer is used to hold the oil phase components and form a stable O / W type emulsion ink composition. Examples of the (acrylates / C10-30 alkyl acrylate) crosspolymer include Pemulen TR-1, TR-2, EZ-4U, Carbopol 1342, 1382, Ultrez 20, Ultrez 21, SC-200, SC-500, ETD 2020 (all manufactured by Lubrizol Corporation), AQUPEC HV-501ER, HV-701EDR, HV-801ERK, HV-803ERK, SW-703ER, SW-705ER (all manufactured by Sumitomo Seika Chemicals Co., Ltd.), and the like. The amount of (acrylates / alkyl acrylate (C10-30)) crosspolymer used is preferably 0.01% by weight or more and 0.50% by weight or less based on the total amount of the O / W emulsion ink composition, since this makes it easier to form a stable O / W emulsion ink composition and makes it easier to eject from a ballpoint pen, and is particularly preferably 0.01% by weight or more and 0.30% by weight or less, since this makes it easier to exert even greater effects. Also, it is preferable that the (acrylates / alkyl acrylate (C10-30)) crosspolymer is mixed in advance with the aqueous phase component, since this makes it easier to form a stable O / W emulsion ink composition.

[0016] In the O / W emulsion ink of the present invention, it is preferable that the oil phase component is 3% by weight or more and 40% by weight or less based on the total weight of the composition, in order to form a stable O / W emulsion ink composition.

[0017] In the present invention, the aqueous phase component is used as the continuous phase of the O / W emulsion ink composition, and the aqueous phase component preferably accounts for 50% by weight or more and 95% by weight or less of the total weight of the composition.

[0018] In the present invention, the emulsion droplets of the emulsified oil phase component preferably have an average droplet diameter of 5 μm to 1 mm, since the difference in color between the aqueous phase and the oil phase is easily noticeable from the beginning of writing and the marbled handwriting is easily recognized.The emulsion droplets of the emulsified oil phase component preferably have an average droplet diameter of 10 μm to 500 μm, since the difference in color between the aqueous phase and the oil phase is more clearly noticeable from the beginning of writing and the marbled handwriting is easily recognized.

[0019] In the present invention, a color difference ΔE between the aqueous phase component and the oil phase component after ejection of 5 or more is preferable because the difference in color between the aqueous phase component and the oil phase component is easily perceived and a marbled handwriting is easily obtained, and a ΔE of 10 or more is preferable because the difference in color between the aqueous phase component and the oil phase component is more clearly perceived and a clearer marbled handwriting is easily obtained. When the color difference between the aqueous phase component and the oil phase component is small, a marbled handwriting with a soft color tone is obtained. When the color difference between the aqueous phase component and the oil phase component is large, the difference in color is clearly perceived and a marbled handwriting with a flashy color tone is obtained.

[0020] In the present invention, sugars can be used in the aqueous phase component for the purpose of obtaining shear thinning properties for smoothly discharging the ink by preventing the ink from leaking from the pen tip by having a high viscosity when left to stand, and by reducing the viscosity due to the shear force of the rotating ball during writing. Specific examples include HPC-SL, HPC-L, HPC-M, and HPC-H (all hydroxypropyl cellulose, manufactured by Nippon Soda Co., Ltd.), Avicel PH-101, PH-102, PH-301, M06, TG-101, Ceolas SC-900, SC-900S, RC591S, RC-N81, RC-N30, CL-611S, DX-2, DX-3, UF-F711, UF-F702, and ST-100. Celluloses such as Ceolas Fiber DF-17, ST-02, FD-101, FD-301, FD-F20, and Ceolas Fiber DF-17 (all crystalline cellulose, manufactured by Asahi Kasei Corporation); Kelzan, S, T, ST, ASX, ASXT, AR, HP, G, Ketorol CG, CG-T, and CG-SFT (all manufactured by Sansho Corporation); San-Ace, S, C, CS, BS, NF, G, ES, NXG-S, and NXG-C. , Bistop D-3000-DF, Bistop D-3000-DF-C (all manufactured by San-ei Gen F.S.I. Co., Ltd.), Kohjin, F, T, K (all manufactured by Kohjin Co., Ltd.), Echo Gum, Echo Gum 630, F, T, GM, RD, SF, 521, LAX-T, Monart Gum GS, HP, HS, KT, Minute GR, MA, Salt (all manufactured by DSP Gokyo Food & Chemical Co., Ltd.), Nomcoat (manufactured by Nisshin Oil Mills, Ltd.) Examples of suitable gums include xanthan gums such as Inagel V-7 and V-7T (all manufactured by Ina Food Industry Co., Ltd.); welan gums such as Rheozan (succinoglucan, manufactured by Sansho Co., Ltd.), K1A96 and BG3810 (all manufactured by Sansho Co., Ltd.); rhamsan gums such as K1A112 and K7C2433 (all manufactured by Sansho Co., Ltd.); guar gums such as Jaguar 8111, Jaguar 8600, Jaguar HP-8, Jaguar HP-60 and CP-13 (all manufactured by Sansho Co., Ltd.); and diutan gums such as Kelco-Care diutan gum, KELCO-VIS DG and DG-F (all manufactured by CP Kelco).Other examples include alkaline, alkaline gum, zeta sea gum, gellan gum, psyllium seed gum, tamarind seed gum, tragacanth gum, galactomannan, carrageenan, ghatti gum, karaya gum, and salts thereof. Xanthan gum is particularly preferred because it has a large shear thinning property, which significantly reduces the viscosity of the ink when writing, resulting in less occurrence of blobbing or line cracking when writing, and because of its stability against temperature changes, pH stability, and salt stability, as well as its compatibility with acylamino acids and / or their salts. Xanthan gum is a polysaccharide composed of glucose, mannose, and glucuronic acid, which is separated and purified from the culture solution of Xanthomonas. The viscosity, viscoelasticity, and shear thinning properties of these sugars can be adjusted by heat treating the sugars or applying high pressure to the sugar solution and applying high shear when passing through a nozzle. The amount of sugar used is preferably 0.05% by weight or more and 5.0% by weight or less based on the total amount of the ink composition, but more preferably 0.1% by weight or more and 2.0% by weight or less based on the total amount of the ink in order to maintain the performance of the ballpoint pen. If the amount is 0.05% by weight or more based on the total amount of the ink composition, the ink is less likely to leak, which is preferable. On the other hand, if the amount is 5.0% by weight or less based on the total amount of the ink composition, the ink discharge from the pen tip becomes more stable, and the writing feel becomes better, which is preferable.

[0021] Fine particles can also be added to prevent wear of the ball holder. Specific examples of fine particles include alumina, silicon carbide, chromium oxide, boron carbide, zircon, rhodium, jadeite, calcium fluoride, tungsten carbide, silica, diamond, garnet, aluminum nitride, and silicon nitride. Among these, alumina is preferred because it can form a stronger sugar network structure when used in combination with sugar. As the alumina particles, high-purity alumina manufactured by Sumitomo Chemical Co., Ltd. AKP-53 (center particle size 0.17 μm), AKP-50 (center particle size 0.20 μm), AKP-30 (center particle size 0.30 μm), AKP-20 (center particle size 0.46 μm), AKP-3000 (center particle size 0.70 μm), AA-03 (center particle size 0.44 μm), AA-04 (center particle size 0.50 μm), AA-05 (center particle size 0.53 μm), Examples of the powders include AA-07 (median particle size 0.83 μm), WA#30000 (median particle size 0.35 μm), WA#20000 (median particle size 0.45 μm), WA#10000 (median particle size 0.60 μm), WA#8000 (median particle size 1.2 μm), and WA#6000 (median particle size 2.0 μm) manufactured by Fujimi Incorporated Co., Ltd., and alumina powders AP005 (median particle size 0.05 μm), AP01 (median particle size 0.1 μm), AP03 (median particle size 0.3 μm), and AP1 (median particle size 1 μm) manufactured by Hartzok Japan Co., Ltd. The median particle size of alumina was measured using a Nanotrac Wave2-EX150 (Microtrack Bell Co., Ltd. dynamic light scattering particle size distribution measuring device) after adding alumina to ethanol and dispersing it for 20 minutes with ultrasonic waves. The median particle size is the diameter at which the larger powder and the smaller powder are equal in amount when the powder is divided into two particles of a certain particle size, and is also called the median diameter or d50. The amount of these fine particles used is preferably 0.001% by weight to 10% by weight, more preferably 0.003% by weight to 0.05% by weight, based on the total amount of the ink composition. These fine particles may be used alone or in combination of two or more kinds.

[0022] Various resins can be used as binders to fix the coloring material of the ink to the paper surface. Specifically, water-soluble resins such as shellac, styrene-maleic acid copolymer, alkali metal salts, amine salts, and ammonium salts of styrene-acrylic acid copolymer, and alkali metal salts, amine salts, and ammonium salts of α-methylstyrene-acrylic acid copolymer can be used. Water-insoluble resins such as acrylic resins, vinyl acetate resins, and styrene-butadiene copolymers can also be used.

[0023] In addition to the above-mentioned components, various additives conventionally used in inks for writing instruments can be used as necessary. For example, sugar alcohols such as sorbitol, xylitol, tetrite, pentitol, hexitol, inositol, maltitol, maltotritol, maltotetratol, maltopentitol, maltohexitol, and maltoheptitol, urea, ethyleneurea, and derivatives thereof can be used to prevent the ink from evaporating. Specifically, PO-10, PO-20, PO-30, and PO-40 (all manufactured by Towa Chemical Industry Co., Ltd.), SE 30, and SE 100 (all manufactured by Nikken Chemical Industry Co., Ltd.), and Diatol L (all manufactured by Sanei Toka Co., Ltd.) can be mentioned. Furthermore, in order to improve the writing feel, lubricants such as polyethylene glycol, polyoxyethylene glycol, polyoxypropylene glycol, alkali metal salts or amine salts of oleic acid, acylamino acids, taurine, methyltaurine, etc., can be used. Specific examples include NIKKOL Sarcosinate CN-30, NIKKOL Sarcosinate CT-30, NIKKOL Sarcosinate LH, NIKKOL Sarcosinate LN, NIKKOL Sarcosinate LN-30, NIKKOL Sarcosinate LK-30, NIKKOL Sarcosinate MN, NIKKOL Sarcosinate OH, NIKKOL Sarcosinate OHV, NIKKOL Sarcosinate PN, NIKKOL Sarcosinate CMT-30, NIKKOL Sarcosinate CMT30-T, NIKKOL Sarcosinate LMT, NIKKOL Sarcosinate LMT-30, NIKKOL Sarcosinate MMT, NIKKOL Sarcosinate PMT, and NIKKOL SMT (all manufactured by Nikko Chemicals Co., Ltd.).

[0024] Further, anionic surfactants such as fatty acid soap, n-acylamino acid salt, alkyl ether carboxylate, acylated peptide, and other carboxylates, alkyl benzene sulfonate, alkyl naphthalene sulfonate, sulfosuccinate, α-olefin sulfonate, N-acylsulfonate, and other sulfonates, sulfated oil, alkyl sulfate, alkyl ether sulfate, alkyl allyl ether sulfate, alkyl amide sulfate, and other sulfate ester salts, alkyl phosphate, alkyl ether phosphate, alkyl allyl ether phosphate, and other phosphoric acid ester salts, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene behenyl ether, polyoxyethylene monotetradecyl ether, polyoxyethylene octyldodecyl ether, polyoxyethylene polyoxypropylene cetyl ether, polyethylene glycol monostearate, polyethylene glycol distearate, polyoxyethylene sorbitan monococonut oil fatty acid, polyoxyethylene sorbitan monopalmitate, polyoxyethylene monolaurate, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene behenyl ether, polyoxyethylene monotetradecyl ether, polyoxyethylene octyldodecyl ether, polyoxyethylene polyoxypropylene cetyl ether, polyethylene glycol monostearate, polyethylene glycol distearate, polyoxyethylene monococonut oil fatty acid, polyoxyethylene sorbitan monopalmitate, polyoxyethylene monolaurate ... Nonionic surfactants such as oxyethylene sorbitan, polyoxyethylene sorbitan monooleate, polyoxyethylene water-added hydrogenated castor oil, decaglyceryl monolaurate, sucrose stearate, sucrose palmitate, sucrose myristate, sucrose oleate, and sucrose laurate; tetramethylammonium chloride, tetramethylammonium hydroxide, tetrabutylammonium chloride, dodecyldimethylbenzylammonium chloride, alkyltrimethylammonium chloride, and alkyltrimethylammonium bromide. cationic surfactants such as ethylhexyl ether dimethicone, benzyl trimethyl ammonium chloride, benzalkonium chloride, benzalthonium bromide, benzethonium chloride, dialkyl dimethyl ammonium chloride, monomethylamine hydrochloride, dimethylamine hydrochloride, trimethylamine hydrochloride, butylpyridinium chloride, dodecylpyridinium chloride, cetylpyridinium chloride, PEG11 methyl ether dimethicone, PEG / PPG-20 / 22 butyl ether dimethicone, PEG-9 dimethicone, PEG-3 dimethicone, PEG-9 methyl ether dimethicone, PEG-10 dimethicone,Silicone surfactants such as PEG-32 methyl ether dimethicone, PEG-9 polydimethylsiloxyethyl dimethicone, lauryl PEG-9 polydimethylsiloxyethyl dimethicone, polyglyceryl-3 disiloxane dimethicone, polyglyceryl-3 polydimethylsiloxyethyl dimethicone, lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone, surface tension adjusters such as fluorine-based surfactants such as perfluorobutane sulfonates, perfluoroalkyl group-containing carboxylates, perfluoroalkylethylene oxide adducts, and perfluoroalkyl group-containing phosphates, and preservatives and antifungals such as sodium dehydroacetate, 1,2-benzoisothiazaline-3-one, and 2-pyridinethiol 1-oxide sodium can also be used as necessary. Benzothiazoline-based preservatives include Proxel GXLS and Proxel GXL (both manufactured by Lonza Japan Co., Ltd.), and pyridinethiol-based preservatives include Sanaivac Sodium Omadine and Sanaivac P-100 (both manufactured by Sanai Oil Co., Ltd.) and Sodium Omadine (manufactured by Lonza Japan Co., Ltd.). Rust inhibitors such as benzotriazole may be used in combination. Alkalinizing agents such as sodium hydroxide, monoethanolamine, diethanolamine, triethanolamine, amine, and ammonium may also be used as pH adjusters.

[0025] The O / W emulsion ink composition for ballpoint pens of the present invention has a viscosity of 50 mPa·s or more and 30,000 mPa·s or less at a temperature of 25°C and a shear rate of 0.35 / s, and the viscosity of the aqueous ink composition for ballpoint pens is adjusted to 50 mPa·s or more and 3,000 mPa·s or less at a temperature of 25°C and a shear rate of 35 / s, thereby ensuring writing performance and storage stability such as writing feel, uniformity of handwriting, handwriting density, control of so-called ink blobs where ink forms beads and is applied to the paper surface, suppression of bleeding, ink discharge stability, control of print-through onto the paper, suppression of handwriting smearing, writing performance when drying, suppression of ink drooping, suppression of ink leakage from the gap between the ball and the tip when the ballpoint pen is not in use, suppression of ink backflow when the writing tip is left facing up, and suppression of pigment sedimentation and separation.

[0026] The aqueous ink composition of the present invention can be produced by various conventional methods. For example, the composition can be easily obtained by mixing and stirring with a stirrer having high shear force, such as a Henschel mixer, a propeller stirrer, a homogenizer, a turbo mixer, or a high-pressure homogenizer. It is preferable to mix the aqueous phase component and the oil phase component after previously preparing them, since this makes it easier to obtain a stable O / W type emulsion ink composition.

[0027] The water-based ink composition of the present invention is used by filling it into a container in which a tip is set in an ink reservoir. The ink reservoir can be made of metal or synthetic resin. If it is made of transparent or translucent synthetic resin, the remaining amount of ink can be clearly indicated. The ink reservoir can be made of, for example, polyethylene, polypropylene, polyurethane, polyethylene terephthalate, polyamide, polyacrylonitrile resin, polyarylate, ethylene-vinyl alcohol copolymer, fluororesin, etc., and polypropylene can be used well in terms of cost and visibility. It is also possible to use an ink reservoir in which dyes, pigments, coloring materials having polarizing properties, etc. are kneaded. The ink reservoir can have an inner diameter of 1.5 mm to 20.0 mm. In order to prevent the ink from drying or flowing back, an ink backflow preventer may be filled at the rear end of the ink. As the ink backflow preventer, various known materials such as high-viscosity nonvolatile liquid, gelled nonvolatile liquid, or sponge-like material can be used, and a float may be used in combination.

[0028] The ballpoint pen tip may have a conventional structure, for example, a ballpoint pen tip formed by pressing the tip of a metal pipe inward from the outer surface to hold the ball in a rotatable state with a part of the ball protruding, or a ballpoint pen tip formed by cutting a metal material with a drill or the like to hold the ball in a rotatable state with a part of the ball protruding from the ball holder. In addition, a spring may be placed behind the ball to press the ball against the inner surface of the ball holder in order to prevent ink from seeping out when not writing. The ball may be made of cemented carbide, stainless steel, ceramic, resin, rubber, or the like. In particular, in order to provide sufficient corrosion resistance and to stabilize the rotation during writing and obtain sufficient ink ejection, a ball made of cemented carbide or a ceramic material such as silicon carbide or silicon nitride is preferable. In order to eject the ink of the present invention sufficiently and obtain marbled handwriting, it is preferable that the amount of ink ejected per 10 m be 0.01 g or more and 0.15 g or less, since this makes it easier to eject the oil phase components and the water phase components without bias.

[0029] The ballpoint pen of the present invention may be of either a cap type or a retractable type, and is not particularly limited. In the case of a retractable ballpoint pen, a single ballpoint pen refill may be accommodated in the barrel, and the tip may be configured to be retractable from the tip hole of the barrel, or a composite type retractable writing instrument may be arranged such that multiple ballpoint pen refills are accommodated in the barrel. In addition, the ballpoint pen may be a ballpoint pen that applies pressure to the ink by sealing compressed air in the ink reservoir, for example, to assist the ink discharge during writing. EXAMPLES

[0030] The present invention will now be described in detail with reference to examples.

[0031] (Preparation of ink composition) Ink compositions of Examples 1 to 17 and Comparative Examples 1 to 3 having the formulations shown in Tables 1 and 2 below were prepared. Specifically, the following materials were used for each composition shown in Tables 1 and 2.

[0032] <Water-compatible solvent> WS-1: Ion-exchanged water WS-2: Ethylene glycol WS-3: Glycerin

[0033] <Water phase colorant> W Colorant-1: Water Yellow #1 (CI Acid Yellow 23, manufactured by Orient Chemical Industries Co., Ltd.) W colorant-2: Daiwa Red No103WB (CI Acid Red 87, manufactured by Daiwa Chemical Industries, Ltd.) W colorant-3: Daiwa Red No104WB (CI Acid Red 92, Daiwa Chemical Co., Ltd.) W colorant-4: Daiwa Blue No. 1 (CI Acid Blue 9, Daiwa Chemical Co., Ltd.) W Colorant-5: Water Yellow #6C (CI Acid Yellow 42, manufactured by Orient Chemical Industries Co., Ltd.)

[0034] <(Acrylates / C10-30 alkyl acrylate) crosspolymer> P-1: Pemulen TR-2 ((Acrylates / C10-30 alkyl acrylate) crosspolymer, manufactured by Lubrizol Corporation) P-2: Pemulen EZ-4U ((Acrylates / C10-30 alkyl acrylate) crosspolymer, manufactured by Lubrizol Corporation)

[0035] <Additives> Additive-1: Benzotriazole Additive-2: Proxel GXL(S) (20% dipropylene glycol solution of 1,2-benzisothiazolin-3-one, manufactured by Lonza Japan Co., Ltd.)

[0036] <Polysaccharides> Polysaccharide-1: Kelzan AR (xanthan gum, manufactured by Sansho Co., Ltd.) Polysaccharide-2: Kelco-Care diutan gum (CP Kelco)

[0037] <pH adjuster> pH adjuster: Sodium hydroxide

[0038] <Oil-phase solvent> OS-1: Benzyl alcohol OS-2: Ethylene glycol monophenyl ether

[0039] <Oil-phase colorant> O colorant-1: Oil Blue 613 (mixture of C.I. Solvent Blue 5 and rosin-modified resin, manufactured by Orient Chemical Industries, Ltd.) O colorant-2: Varifast Red 1364 (salt-forming dye of C.I. Basic Red 1:1, alkylbenzene sulfonic acid, and alkyldiphenyl ether disulfonic acid, manufactured by Orient Chemical Industries, Ltd.)

[0040] The ink compositions of each example and comparative example were prepared as follows. <Examples 1 to 17, Comparative Examples 1 to 3> The total amount of the polysaccharide was added to 10% by weight of ion-exchanged water while stirring with a propeller stirrer, and stirred for 1 hour to obtain an aqueous polysaccharide solution. Next, the remaining aqueous-phase components were mixed, stirred with a propeller stirrer for 1 hour until uniformly dissolved, and then the aqueous polysaccharide solution was added and stirred for another 2 hours to obtain an aqueous phase. Also, an oil phase was obtained by heating and stirring each component of the oil-phase components with a propeller stirrer for 2 hours. An O / W type emulsion ink composition was obtained by stirring the aqueous-phase component and the oil-phase component with a propeller stirrer for 1 hour.

[0041] A ball pen tip (ball diameter 1.0 mm) was connected to the ink container used in Hybrid Dual Metallic K110 (Pentel Co., Ltd.) via a ball pen tip holder. The O / W type emulsion ink compositions obtained in Examples 1 to 17 and Comparative Examples 1 to 3 were filled into this ink container to about 0.8 g. After arranging an ink backflow preventer in layers at the ink interface, centrifugal defoaming was performed while temporarily sealing the pen tip with a rubber packing so that the pen tip faced outward to produce a test ball pen.

[0042] <Comparative Example 4> Pastel pink ink and pastel blue ink were taken out from the pastel pink (K108J-PP) and pastel blue (K108J-PS) of Hybrid Milky K108J (Pentel Co., Ltd.). A ballpoint pen tip (ball diameter 1.0 mm) was connected to the ink container used in Hybrid Dual Metallic K110 (Pentel Co., Ltd.) via a ballpoint pen tip holder, and the taken out pastel pink ink and pastel blue ink were alternately filled into this ink container at 0.1 g each until a total of 0.8 g was reached. After that, an ink backflow prevention body was placed in layers at the ink interface, and the pen tip was temporarily sealed with a rubber packing while centrifugal degassing was performed so that the pen tip faces outward, to prepare a test ballpoint pen.

[0043] The test samples of the ballpoint pens described above were used to carry out the tests described below.

[0044] (Measurement of brightness and color of water and oil phases) The lightness and chromaticity of the water phase and oil phase were measured by rotating a test sample ballpoint pen around its longitudinal axis at a writing angle of 70°, a writing speed of 7 cm / s, and a writing load of 981 mN, while drawing a spiral of 10 cm (diameter 32 mm) at a pitch of 2 mm. The lightness (L * ) Chromaticity (a * b * The lightness and chromaticity of the aqueous phase were measured at three points, and the average values ​​were taken as the lightness and chromaticity of the aqueous phase. The lightness and chromaticity of the oil phase were measured at three points, and the average values ​​were taken as the lightness and chromaticity of the oil phase.

[0045] (How to calculate the color difference ΔE between the water phase and the oil phase) Using the lightness and color measured in the lightness and color measurement of the water phase and oil phase, the color difference ΔE between the water phase and the oil phase was calculated as ΔE = ((water phase L * -Oil phase L * ) 2 +(aqueous phase a * -Oil phase a * ) 2 +(aqueous phase b *-Oil phase b * ) 2 ) 0.5 It was calculated as:

[0046] (Measurement of coverage of oil phase components over the entire handwriting) The coverage rate of the oil phase component to the entire handwriting was measured by rotating a test sample ballpoint pen around its longitudinal axis at a writing angle of 70°, a writing speed of 7 cm / s, a writing load of 981 mN, and a spiral of 10 cm (diameter 32 mm) with a pitch of 2 mm. The image was taken at a magnification of 300 times with an optical microscope (digital microscope VHX-2000, manufactured by Keyence Corporation). The area of ​​the entire handwriting and the area of ​​the oil phase component were measured using an area measuring tool built into the measuring device, and the ratio of the area of ​​the oil phase component to the area of ​​the entire handwriting was calculated as (area of ​​oil phase component) ÷ (area of ​​entire handwriting). The average value of the ratio of the area of ​​the oil phase component to the area of ​​the entire handwriting was measured at three points and used as the coverage rate. The coverage rates at the beginning and end of writing for the test sample ballpoint pen were compared. A coverage rate of 5% or more is preferable because it is easy to obtain a marbled handwriting.

[0047] [Table 1]

[0048] [Table 2]

[0049] The O / W type emulsion ink compositions for ballpoint pens of Examples 1 to 15 had a color difference ΔE between the water phase and the oil phase of 5 or more, so that the marbled pattern of the handwriting could be recognized from the beginning of writing, and since the coverage rate was maintained from the beginning to the end of writing, no color bias was observed, and the marbled pattern could be enjoyed equally from the beginning to the end of writing.

[0050] In contrast, in Comparative Example 1, no (acrylates / alkyl acrylate (C10-30)) crosspolymer was blended, and the emulsion dispersion was not maintained in the tip, so the aqueous phase component and the oil phase component were mixed, and the marbled pattern of the handwriting could not be recognized. In Comparative Example 2, no colorant was blended in the aqueous phase component, and in Comparative Example 3, no colorant was blended in the oil phase component, so the handwriting was monochromatic and the marbled pattern could not be recognized. In Comparative Example 4, inks of different colors were alternately filled, so due to color bias in the ink tank and tip, no color change was felt even with just a little writing, and the marbled pattern of the handwriting could not be recognized.

[0051] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and also includes modifications to the above-described embodiments and appropriate combinations of these modifications.

[0052] In this specification, expressions such as "identical," "equal," and "homogeneous" that indicate that things are in an equal state not only indicate a state of strict equality, but also indicate a state in which there is a tolerance or a difference to the extent that the same function is obtained. In addition, in this specification, the expressions "comprise," "include," or "have" a certain element are not exclusive expressions that exclude the presence of other elements.

Claims

1. The present invention provides an O / W type emulsion ink composition for a ballpoint pen, comprising: an aqueous phase component including at least water and a colorant; an oil phase component including at least an organic solvent having a solubility of 5 g or less in 100 g of water at 20° C. and a colorant; and an (acrylates / alkyl acrylate (C10-30)) crosspolymer, wherein the oil phase component is emulsified and dispersed in the aqueous phase component.

2. 2. The O / W type emulsion ink composition for ballpoint pens according to claim 1, wherein the water phase component and the oil phase component are different in color.

3. 3. The O / W type emulsion ink composition for ballpoint pens according to claim 1, wherein the amount of the (acrylates / C10-30 alkyl acrylate) crosspolymer added is 0.01% by weight or more and 0.50% by weight or less based on the total amount of the O / W type emulsion ink composition.

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