JP2010053232A - O/w type emulsion ink composition for ball-point pen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink composition for ball-point pens, which is free from set-off of writing, is excellent in water resistance and is excellent in writing feeling. <P>SOLUTION: In the O/W type emulsion ink composition for ball-point pens, an oil-soluble dye solution used as a colorant is dispersed in water by using an additive selected from chimyl alcohol and/or batyl alcohol and a sodium salt of acyl-lactate having at least 8 carbon atoms. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an O / W emulsion ink composition for ball-point pens which has excellent water resistance of handwriting, no show-through and bleeding, and excellent writing feeling.

Conventionally, water-based ballpoint pen inks and water-based ballpoint pen inks that use water-soluble dyes have the characteristics that the handwriting is vivid and the writing feeling is good, but the disadvantage is that the water resistance of the handwriting is inferior because the colorant is a water-soluble dye. There is. For this reason, the invention described in JP-A-10-306243 (Patent Document 1) includes a fluorine compound containing a fluoroalkyl group and an amino group in the molecule, a water-soluble dye, and an aqueous medium. Ink imparted with water resistance is disclosed. In addition to this, many inks in which a colorant is a pigment that does not dissolve in water are disclosed.
Japanese Patent Laid-Open No. 10-306243

  Conventionally, water-based ballpoint pen inks that use a water-soluble dye as a colorant have the disadvantage of being inferior in the water resistance of handwriting. However, as in the invention described in Patent Document 1, the water repellent property is used to impart water resistance to the handwriting. Addition of a water-containing fluorine compound lowers the surface tension of the ink, which may cause handwriting bleeding or ink leakage from the pen tip.

  In addition, there are many inks that impart water resistance to the handwriting by using a colorant as a pigment. However, if the colorant is a pigment, the color of the handwriting is inferior. If a large amount of pigment is added, the ink viscosity increases and the writing feeling is increased. There is a problem that the writing density is lower than that of water-based dye inks.

Conventional oil-based ballpoint pens use oil-soluble dyes to provide handwriting with water resistance, but conventional oil-based ballpoint pens allow the organic solvent, which is the main solvent, to easily penetrate into the paper, and the handwriting Since the show-through and handwriting that reaches the back of the paper surface is blurred, the ink flow is reduced by adding a relatively large amount of resin to prevent the show-through and bleeding, but the viscosity is high. There is a problem that writing feeling is heavy.
The inventor of the present application thought that if oil-soluble dyes can be used in water-based inks, it was thought that water-resistant and non-exposed handwriting could be formed, but an O / W emulsion in which an oil-based component in which oil-soluble dyes are dissolved is dispersed in water. In emulsification with a general nonionic surfactant during formation, a surfactant having a high HLB is required in order to orient the hydrophilic group at the interface of the oil droplets. However, since the surfactant having a high HLB is water-soluble, re-emulsification of the emulsion occurs on the handwriting, and the water resistance of the handwriting cannot be obtained even though the oil-soluble dye is used. In addition, in order to prevent sedimentation and separation of oil droplets, a larger amount of surfactant is required as the particle size is reduced, which increases the penetrating power of the emulsion ink and causes show-through and bleeding despite being aqueous. There is a problem.

  An object of the present invention is to provide an O / W emulsion ink composition for ball-point pens that uses an oil-soluble dye as a colorant, has excellent water resistance of handwriting, has no show-through and blurring, and has excellent writing feeling. .

  The present invention comprises an oil-soluble dye as a colorant, an organic solvent that dissolves the dye, chimyl alcohol and / or batyl alcohol, and an oil component containing at least a sodium salt of acyl lactic acid having 8 or more carbon atoms in water. The gist of the present invention is an emulsified and dispersed O / W emulsion ink composition for ballpoint pens.

The sodium salt of acyl lactic acid having 8 or more carbon atoms has little water solubility and high water resistance of handwriting, but its emulsifying power is small and it cannot emulsify a sufficient amount of oily component by itself. An O / W type emulsion can be prepared by using this together with chimyl alcohol and / or batyl alcohol. The handwriting of emulsion ink made with this combination is that the solid phase of chimyl alcohol and / or batyl alcohol rides on the paper surface together with the oil-soluble dye, and the water phase component is absorbed into the fiber of the paper and the handwriting on the paper surface. Is immediately dry and good, with no handwriting show-through or bleeding, and excellent water resistance. Further, since the sodium salt of acyllactic acid and chimyl alcohol and / or batyl alcohol are both water-insoluble, re-emulsification of the ink does not occur even if the handwriting gets wet.
Therefore, handwriting with an O / W emulsion ink obtained by emulsifying a solution of an oil-soluble dye in water using the active agent in the above combination is excellent in water resistance, has no show-through and bleeding, and has a low ink viscosity, so the writing feeling is light. .

  The chimyl alcohol and batyl alcohol used in the present invention is a linear, normal-temperature solid alkyl glyceryl ether, and when used in combination with a sodium salt of acyl lactic acid having 8 or more carbon atoms, an organic solvent in which the dye is dissolved is used as an oil. It can be dispersed in water as drops.

  If the sodium salt of acyllactic acid used in the present invention is not one having 8 or more carbon atoms, the performance as an emulsifier is poor and a good emulsifier composition cannot be obtained. In addition, a stable emulsion can be obtained if it is a sodium salt. However, in the case of acyl lactic acid or its calcium salt or magnesium salt, the emulsion may be destroyed due to precipitation or aggregation of oil-soluble dyes. Examples of the sodium salt of acyl lactic acid used in the present invention include, for example, caproyl lactate sodium salt, 2-ethylhexanoyl lactate sodium salt, lauroyl lactate sodium salt, myristoyl lactate sodium salt, palmitoyl lactate sodium salt, stearoyl lactate sodium salt , Sodium isostearoyl lactate, oleoyl lactate sodium salt, 12-hydroxystearoyl lactate sodium salt, ricinooleyl lactate sodium salt, and the like. These may be used in combination.

As the colorant, dyes conventionally used in oil-based ballpoint pen inks can be used without limitation. As the dye, acid dyes, basic dyes, metal complex dyes, salt-forming dyes, azine dyes, anthraquinone dyes, phthalocyanine dyes, triphenylmethane dyes and the like can be used. Specifically, Bali First Yellow # 3104, Bali First Yellow # 3105, Bali First Yellow # 1105, Bali First Yellow AUM, Orient Spirit Black AB, Bali First Black # 3804, Bali First Black # 3806, Bali First Black # 1802, Bali First Black # 1805, Bali First Yellow # 1109, Bali First Orange # 2210, Bali First Red # 1320, Bali First Blue # 1605, Bali First Violet # 1701, Orient Oil Scarlet # 3 8. Nigrosine Base EX-BP (Oil-based dye manufactured by Orient Chemical Co., Ltd.), Spiron Black GMH Special, Spiron Yellow C-2GH, Spiron Red C-GH, Spiron Red C-BH, Spiron Blue BPNH, Spiro Blue C-RH, Spiron Violet C-RH, S. P. T. T. Orange 6, S. P. T. T. Blue-111 (above, oil-based dye manufactured by Hodogaya Chemical Co., Ltd.), Rhodamine B base (CI. 45170B, oil-based dye manufactured by Sumitomo Chemical Co., Ltd.), Victoria Blue F4R, Nigrosine Base LK (Germany) Country, manufactured by BASF), methyl violet 2B base (manufactured by National Anil Div.), Etc. can be used.
These may be used alone or in combination.
The O / W emulsion oily component must be at least an ink component obtained by dissolving an oil-soluble dye as a colorant in an organic solvent, and the amount of the oil-soluble dye added is preferably 1 to 50% by weight of the oily component, preferably 10 wt% or more and 30 wt% or less can be used. If the amount used is small, the handwriting density becomes thin when it is made into an emulsion. If the amount is large, the dye may precipitate over time, clog the ball-point pen tip and ink may not be ejected, or the handwriting show-through or blur may occur.

  As the organic solvent that can be used for the oily component of the emulsion, an organic solvent that has been conventionally used in oil-based ballpoint pens and that can dissolve oil-soluble dyes and that does not substantially dissolve in water can be used. For example, ethylene glycol monoether solvents such as ethylene glycol monoethyl ether, ethylene glycol monohexyl ether, ethylene glycol mono 2-ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol mono 2 -Diethylene glycol monoether solvents such as ethylhexyl ether, propylene glycol mononormal butyl ether, propylene glycol monophenyl ether, dipropylene glycol mononormal propyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monophenyl ether, tripropylene glycol monobutyl ether, Of and propylene glycol monomethyl ether solvent, benzyl alcohol, beta-phenylethyl alcohol, alcohol solvents such as α- methylbenzyl alcohol can be used. These may be used singly or as a mixture of two or more, and the blending amount is 1% by weight or more and 90% by weight or less based on the oil phase of the emulsion ink composition.

  Water is used as an essential component of the O / W emulsion ink. This water is preferably ion-exchanged water in order to stabilize the dissolution of the dye or resin. In addition to these essential components, conventionally known viscosity modifiers, dye dissolution accelerators, various resins and resin emulsions as fixing agents, antioxidants, ultraviolet absorbers, antiseptics, rust inhibitors, antifoaming agents, pH A regulator and a lubricant for preventing ball seat wear and improving the brushing performance can be appropriately used in both the oil phase and the water phase as necessary.

  In order to impart desirable viscosity and rheological performance as a ballpoint pen ink, a high molecular weight polysaccharide, a water-soluble acrylic resin, an inorganic mineral thickener, and the like can be used as an aqueous component.

  The oil component containing the oil-soluble dye with respect to the total amount of the O / W emulsion ink is 10% by weight or more and 45% by weight or less, and the emulsifier component which is a mixture of the sodium salt of chimyl alcohol and / or batyl alcohol and acyl lactic acid is 0. It is preferable that the content is 5% by weight or more and 10% by weight or less, and the aqueous component is 45% by weight or more and 89.5% by weight or less.

  The method of emulsification and dispersion for preparing the O / W emulsion ink is not particularly limited, and can be prepared by stirring at an appropriate temperature with a stirrer, homomixer, homogenizer or the like. Moreover, in order to make the produced emulsion further finer, it can also be subjected to a high-pressure homogenizer treatment, and can also be subjected to filtration or centrifugal treatment to make the emulsion particle size uniform or to remove insoluble matter.

Example 1
Spiron Violet C-RH (Colorant: Hodogaya Chemical Co., Ltd.) 7.50% by weight
Spiron yellow C-GNH (colorant: manufactured by Hodogaya Chemical Co., Ltd.) 5.00% by weight
Benzyl alcohol 27.00% by weight
Kimyl alcohol 3.50% by weight
Sodium stearoyl lactate 3.50% by weight
Glycerin 10.00% by weight
Ion-exchanged water 43.50% by weight
Components other than the above glycerin and ion-exchanged water are heated and stirred at 80 ° C. for 1 hour, glycerin is added, and the mixture is further stirred at 80 ° C. for 1 hour to prepare solution A. Ion exchange water was added to the liquid A at 80 ° C., and the mixture was stirred for 15 minutes with a magnetic stirrer and then cooled with stirring to prepare a black emulsion ink.

Example 2
Spiro Yellow C-GNH (Colorant: Hodogaya Chemical Co., Ltd.) 2.50% by weight
Spiron red C-GH (colorant: manufactured by Hodogaya Chemical Co., Ltd.) 3.00% by weight
Spiron Red C-BH (Coloring agent: Hodogaya Chemical Co., Ltd.) 4.00% by weight
Benzyl alcohol 5.50% by weight
Ethylene glycol monophenyl ether 15.00% by weight
Batyl alcohol 2.00% by weight
Sodium stearoyl lactate 2.00% by weight
Ethylene glycol 35.00% by weight
Ion-exchanged water 32.00% by weight
Components other than the ethylene glycol and ion-exchanged water are heated and stirred at 80 ° C. for 1 hour to prepare solution A. Ethylene glycol and ion-exchanged water are stirred at 20 ° C. for 10 minutes to prepare solution B. The B liquid was heated to 75 ° C. with a three-one motor and the A liquid was added dropwise with stirring and stirred at 75 ° C. for 45 minutes, and then cooled with stirring to prepare a red emulsion ink.

Example 3
Spiro Yellow C-GNH (Colorant: Hodogaya Chemical Co., Ltd.) 0.15% by weight
Spiron Red C-GH (Coloring agent: Hodogaya Chemical Co., Ltd.) 0.15% by weight
Spiron Red C-BH (colorant: manufactured by Hodogaya Chemical Co., Ltd.) 1.30% by weight
Ethylene glycol monophenyl ether 15.00% by weight
Kimyl alcohol 0.50% by weight
Batyl alcohol 0.50% by weight
Isostearoyl sodium lactate 1.50% by weight
Glycerin 40.00% by weight
Ion-exchanged water 40.90% by weight
Components other than the above glycerin and ion-exchanged water are heated and stirred at 80 ° C. for 3 hours to prepare Liquid A. Liquid A was added dropwise with stirring of glycerin heated to 80 ° C. and ion-exchanged water with a homogenizer and treated for 5 minutes, and then cooled with stirring with a three-one motor to prepare a pink emulsion ink.

Example 4
Spiro Yellow C-GNH (Colorant: Hodogaya Chemical Co., Ltd.) 2.90% by weight
Spiron Red C-GH (Coloring agent: manufactured by Hodogaya Chemical Co., Ltd.) 1.30% by weight
Benzyl alcohol 10.00% by weight
Batyl alcohol 1.00% by weight
Sodium stearoyl lactate 0.20% by weight
Kelzan AR (xanthan gum: manufactured by Sanki Co., Ltd.) 0.50% by weight
Ion-exchanged water 84.10% by weight
Components A other than the Kelzan AR and ion-exchanged water are heated and stirred at 80 ° C. for 1 hour to prepare A liquid. Kelzan AR and ion-exchanged water are stirred at 20 ° C. for 1 hour to prepare solution B. Liquid B was heated to 75 ° C. with a three-one motor, and liquid A was added dropwise with stirring. After stirring for 45 minutes at 75 ° C., the mixture was cooled with stirring to prepare an orange emulsion ink.

Comparative Example 1
Spiron Violet C-RH (Colorant: Hodogaya Chemical Co., Ltd.) 7.50% by weight
Spiron yellow C-GNH (colorant: manufactured by Hodogaya Chemical Co., Ltd.) 5.00% by weight
Benzyl alcohol 27.00% by weight
Kimyl alcohol 3.50% by weight
Sodium stearoyl lactate 3.50% by weight
Ethylene glycol monophenyl ether 43.50% by weight
The above components were heated and stirred at 80 ° C. for 3 hours to dissolve the dye to prepare a black oil-based ink.

Comparative Example 2
In Example 2, instead of sodium stearoyl lactate, polyoxyethylene (10) oleyl ether (hydrophilic emulsifier of HLB = 14) which is a nonionic surfactant was changed to 4.00% by weight, and ion-exchanged water was 29.00% by weight. A red emulsion ink was prepared in the same manner as in Example 2 except that the percentage was changed to%.

Comparative Example 3
A pink emulsion ink was prepared in the same manner as in Example 3 except that in the example 3, chimyl alcohol and batyl alcohol were replaced with isostearyl glyceryl ether (branched alkyl glyceryl ether).

Comparative Example 4
An orange emulsion ink was prepared in the same manner as in Example 4 except that the entire amount of batyl alcohol was replaced with ion-exchanged water in Example 4.

Visual observation of emulsion 10 g of each ball-point pen ink composition obtained in Examples 1 to 4 and Comparative Examples 1 to 4 was placed in a screw cap glass bottle with a lid (19 × 70 mm, manufactured by Nidec Rika Glass Co., Ltd.), and 25 ° C. After standing for 1 week, the state of the emulsion was visually observed.

Preparation of test samples Knock-type ballpoint pens having a ballpoint pen tip holding the ball-point pen ink compositions obtained in Examples 1 to 4 and Comparative Examples 1 to 4 and having a diameter of 0.5 mm. 1.7 g of the ink containing tube of the formula Energel, product code BLN75, manufactured by Pentel Co., Ltd. was filled into a test ballpoint pen sample.

Handwriting Water Resistance Test Each ball-point pen test sample is handwritten on JIS P3201 writing paper A by hand with 15 continuous circles having a diameter of about 2 cm twice, left for 1 hour, and then immersed in ion-exchanged water for 1 hour. Then, it took out from water and determined the degree of fading with a gray scale (JIS L-0804).
The gray scale is from 1 to 5, and the larger the number, the smaller the density difference between the handwriting before and after the test, indicating water resistance.

Back-printing of handwriting Each ball-point pen test sample was handwritten on JIS P3201 writing paper A with 15 consecutive circles of about 2 cm in diameter twice and left for 1 day in an environment of 30 ° C and 60% RH. Was observed.
The case where there was no ink oozing was rated as ◎, the case where there was only a slight bleed out was marked as ◯, and the case where there was clearly oozing out was marked as ×.
The results of each test are shown in Table 1.

  As described above in detail, the O / W type emulsion ink composition of the present invention has a good writing quality with excellent performance of water resistance for show-through of handwriting.

Claims (1)

An oil component containing at least an oil-soluble dye as a colorant, an organic solvent for dissolving the dye, chimyl alcohol and / or batyl alcohol, and a sodium salt of acyl lactic acid having 8 or more carbon atoms is emulsified and dispersed in water. O / W emulsion ink composition for a ballpoint pen.