JP2926455B2 - W / O emulsion ink - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a W / O emulsion ink, and more particularly, to a W / O emulsion ink having improved ink fixability on printed images.

[0002]

2. Description of the Related Art In recent printing technologies, there have been remarkable technological advances, and it has become possible to obtain better printed materials. Further, it is required that the image of the printed matter can be stored as it is. However, in the case of conventional W / O emulsion ink images, the non-image area is stained by the friction between the paper and the paper after printing or the image is touched when handled by hand. The hands of the elderly were soiled, and there was a problem with hygiene. This is because pigments that are conventionally used as colorants for emulsion inks and that have a diameter larger than the pores on the paper surface, or that oil or other vehicles penetrate into the paper quickly and are left on the paper. Is separated by friction between paper and paper or a worker's hand, and adheres to a non-image area or a hand.

[0003]

Heretofore, in order to improve the above-mentioned disadvantages, a varnish has been added to the ink.
Measures have been taken to increase the fixing property between the pigment and the paper and to increase the fixing property. However, even with this, the above-described problem has occurred, and further improvement in fixability is required.

Accordingly, it is an object of the present invention to provide a W / O emulsion ink which solves the above-mentioned disadvantages, maintains a good printed image, and does not stain the hands with the printed image.

[0005]

SUMMARY OF THE INVENTION The present inventor has developed a novel W / O emulsion ink which does not impair the safety and storage stability of the W / O type emulsion ink, and has other properties such as set-off, show-through, see-through, and bleeding in an image. Without having any drawbacks in properties, we have conducted extensive research to improve fixing properties and eliminate stains on non-image areas and hands due to friction.As a result, by including specific aluminum chelates in the oil phase, The inventors have found that the above objects can be achieved, and have reached the present invention.

That is, according to the present invention, a W / O emulsion for stencil printing which comprises 10 to 50% by weight of an oil phase and 90 to 50% by weight of an aqueous phase and contains a pigment, an emulsifier, an oil, a resin and water. A W / O emulsion ink for stencil printing, characterized in that the oil phase contains at least one of aluminum chelates represented by the following structural formula.

Embedded image

Embedded image (In the formula, R represents a C ₁₈ H ₃₅ group.)

In the oil phase of a W / O emulsion ink,
When the aluminum chelates represented by the structural formulas 1 and 2 are contained, the pigment dispersed in the oil phase of the emulsion can be kept extremely fine. Accordingly, the pigment also penetrates into the fine pores of the paper together with the vehicle, and hardly remains on the paper, and peeling due to friction is significantly reduced. Therefore, by including at least one of the aluminum chelates represented by the structural formulas (1) to (2) in the oil phase of the W / O emulsion ink, fixability can be significantly improved.

Hereinafter, the present invention will be described in more detail. The W / O emulsion ink of the present invention comprises aluminum chelates represented by the above-mentioned structural formulas (1) to (2) in which the oil phase comprises 10 to 50% by weight and the water phase 90 to 50% by weight. Characterized by containing at least one of the following. The oil phase is composed of a pigment, a dispersant, a resin, an oil, an emulsifier, a gelling agent, the aluminum chelate, and the like, and the aqueous phase is water, a water-soluble resin, a preservative, a water evaporation inhibitor, an antifreezing agent. , A pH adjuster, an antioxidant, an electrolyte and the like.

The aluminum chelates to be added to the oil phase are those represented by the aforementioned structural formulas 1 to 2, and may be used alone or in combination. The amount used is preferably 0.01 to 5.00% by weight based on the ink. Examples of the pigment in the oil phase include azo pigments, phthalocyanine pigments, nitroso pigments, nitro pigments, vat dye pigments, mordant dye pigments, basic dye pigments, acid dye pigments, and natural dyes. Known pigments such as a system pigment are exemplified. These can be used alone or in combination. The amount of the pigment used is preferably 1 to 20% by weight based on the ink.

As a pigment dispersant in an oil phase, or as W /
Examples of the emulsifier for constituting the O-type emulsion include glycerin fatty acid ester, polyglycerin fatty acid ester, propylene glycol fatty acid ester, pentaerythritol fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbite fatty acid ester, and polyoxyethylene glycerin fatty acid. Ester, polyethylene glycol fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene phytosterol, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene castor oil, polyoxyethylene hardened castor oil, polyoxyethylene lanolin, Polyoxyethylene lanolin alcohol, polyoxyethylene alcohol Triethanolamine, polyoxyethylene fatty acid amides, nonionic surfactants such as polyoxyethylene alkylphenyl formaldehyde condensates and the like. These can be used alone or in combination. The use amount of the surfactant is preferably 1 to 20% by weight based on the ink.

As the oil, known mineral oils, vegetable oils, and synthetic hydrocarbon oils can be used alone or in combination. Mineral oils include petroleum solvents, spindle oils, liquid paraffin, motor oils, gear oils, and machine oils, and vegetable oils include linseed oil, tall oil, corn oil, soybean oil, castor oil, and dehydrated castor oil. No. These can be used alone or in combination. The amount of the oil used is preferably 5 to 30% by weight based on the ink.

Resins are used for the purpose of improving the adhesion between ink and paper, the stability over time of the ink, and the dispersibility of the pigment in the oil phase. Examples of the resin include rosin, polymerized rosin, hydrogenated rosin, Examples include rosin esters, hydrogenated rosin esters, rosin-modified phenols, alkyd resins, and castor oil. These can be used alone or in combination. The amount of the resin used is preferably 1 to 15% by weight in the ink. In addition, a gelling agent can be appropriately selected and used for the oil phase in order to improve the stability of the ink.

The water used for the aqueous phase is tap water, purified water,
Any of ion-exchanged water may be used, and the use amount is preferably 20 to 70% by weight based on the ink. As the water-soluble resin used for moisturizing or thickening, acrylic resin, gum arabic and the like are used. The amount used is preferably from 1 to 15% by weight based on the ink.

To suppress water evaporation or prevent freezing, a water-soluble organic solvent may be used in the aqueous phase. Examples thereof include glycols such as ethylene glycol, diethylene glycol, propylene glycol, methanol, ethanol, isopropanol, and the like. Alcohols such as butanol and isobutanol; and glycerin. These organic solvents can be used alone or in combination. The amount used is preferably 0.5 to 10% by weight based on the ink.

In addition, a preservative, a pH adjuster, an antioxidant, an electrolyte for stabilizing an emulsion, a rust inhibitor for preventing corrosion of metal parts, an antifoaming agent, etc. may be used alone or in plural in the aqueous phase. Can be selected and used.

In the oil phase, a pigment is usually dispersed by a known dispersing machine, and the pigment is diluted with an oil or another oil phase composition.
In general, a known stirrer is used for dilution. In the aqueous phase,
The aqueous phase composition is usually mixed by a stirrer. The completed oil phase and aqueous phase are easily emulsified using a known emulsifier. Production methods and means such as dispersion, dilution, and emulsification can be appropriately changed.

[0017]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. In addition, all the parts shown below are based on weight.

Example 1 Carbon black (colorant) 3.0 parts Spindle oil (solvent) 15.0 parts Rosin-modified phenol resin (resin) 5.0 parts Aluminum chelate (trade name: Plainact Al-M, structural formula described above) 0.3 part Sorbitan sesquioleate (emulsifier) 4.0 parts Dibutylhydroxytoluene (antioxidant) 0.1 part Water 72.5 parts Methyl parahydroxybenzoate (preservative) 0.1 Department

The above-mentioned rosin-modified phenol resin was heated and dissolved in spindle oil at 150 ° C., and carbon black, aluminum chelate, sorbitan sesquioleate and dibutylhydroxytoluene were subjected to dispersion treatment with a three-roll mill to obtain an oil phase. . While gradually adding an aqueous solution in which methyl parahydroxybenzoate was dissolved to the oil phase, the mixture was stirred with a conventionally known emulsifier to obtain an emulsion ink having the above composition. Using this emulsion ink, printing was performed with a VT3500 machine manufactured by Ricoh Company. I. of the print image D. Was measured with a Macbeth densitometer (manufactured by Macbeth), and the I.C. D. Was measured, and the ratio between the two was calculated. Hereinafter, this ratio is referred to as a fixing rate.

Example 2 Phthalocyanine blue (colorant) 3.0 parts Spindle oil 15.0 parts Rosin-modified phenol resin 5.0 parts Aluminum chelate (trade name: Plainact Al-M) 0.3 parts Sorbitan sesquioleate 4 0.0 parts Dibutylhydroxytoluene 0.1 parts Water 72.5 parts Methyl parahydroxybenzoate 0.1 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Example 3 Phthalocyanine green (colorant) 3.0 parts Spindle oil 15.0 parts Rosin-modified phenolic resin 5.0 parts Aluminum chelate (trade name: Plainact Al-M) 0.3 parts Sorbitan sesquioleate 4 0.0 parts Dibutylhydroxytoluene 0.1 parts Water 70.8 parts Methyl parahydroxybenzoate 0.1 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Example 4 Strontium red (colorant) 3.0 parts Spindle oil 15.0 parts Rosin-modified phenolic resin 5.0 parts Aluminum chelate (trade name: Plainact Al-M) 0.3 parts Sorbitan sesquioleate 4 0.0 parts Dibutylhydroxytoluene 0.1 parts Water 72.5 parts Methyl parahydroxybenzoate 0.1 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Example 5 Carbon black 5.0 parts Petroleum solvent (solvent) 25 parts Alkyd resin (resin) 5.0 parts Aluminum chelate (trade name: Aluminum chelate D, compound represented by the above structural formula 1) 5 parts Sorbitan Yasquioleate 5.0 parts Dibutylhydroxytoluene 0.1 parts Water 54.7 parts Methyl parahydroxybenzoate 0.1 parts Glycerin (water evaporation inhibitor) 4.6 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Example 6 Carbon black 5.0 parts Petroleum solvent 25 parts Alkyd resin 5.0 parts Aluminum chelate (trade name: Plainact Al-M) 0.2 parts Aluminum chelate (trade name: ALCH) 0.3 parts Sorbitan Sesquioleate 5.0 parts Dibutylhydroxytoluene 0.1 parts Water 54.7 parts Methyl parahydroxybenzoate 0.1 parts Glycerin 4.6 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Comparative Example 1 Carbon black 3.0 parts Spindle oil 15.3 parts Rosin-modified phenol resin 5.0 parts Sorbitan sesquioleate 4.0 parts Dibutylhydroxytoluene 0.1 parts Water 72.5 parts Methyl paraoxybenzoate 0.1 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Comparative Example 2 Phthalocyanine Blue 3.0 parts Spindle oil 15.3 parts Rosin-modified phenolic resin 5.0 parts Sorbitan sesquioleate 4.0 parts Dibutylhydroxytoluene 0.1 parts Water 72.5 parts Methyl paraoxybenzoate 0.1 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Comparative Example 3 Phthalocyanine Green 3.0 parts Spindle oil 15.3 parts Rosin-modified phenolic resin 5.0 parts Sorbitan sesquioleate 4.0 parts Dibutylhydroxytoluene 0.1 parts Water 72.5 parts Methyl paraoxybenzoate 0.1 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Comparative Example 4 Strontium Red 3.0 parts Spindle oil 15.3 parts Rosin-modified phenolic resin 5.0 parts Sorbitan sesquioleate 4.0 parts Dibutylhydroxytoluene 0.1 parts Water 72.5 parts Methyl paraoxybenzoate 0.1 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Comparative Example 5 Carbon black 5.0 parts Petroleum-based solvent 25.5 parts Alkyd resin 5. Part Sorbitan sesquioleate 5.0 parts Dibutylhydroxytoluene 0.1 part Water 54.7 parts Methyl parahydroxybenzoate 0.1 part Glycerin 4.6 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Comparative Example 6 Carbon black 5.0 parts Petroleum solvent 25.5 parts Alkyd resin 5.0 parts Sorbitan sesquioleate 5.0 parts Dibutylhydroxytoluene 0.1 parts Water 54.7 parts Methyl paraoxybenzoate 0 .1 part Glycerin 4.6 parts

The above composition was emulsified in the same manner as in Example 1 to obtain an emulsion ink. Printing was performed with VT3500 using this emulsion ink, and Example 1 was used.
The fixing rate was measured in the same manner as described above.

Examples 1, 2, 3, 4 and Comparative Examples 1, 2,
Tables 1 to 4 show the results of Examples 3 and 4, Examples 5, 6 and Comparative Example 5, and Examples 7 and Comparative Example 6, respectively.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

[Table 3]

[0046]

[Table 4]

From the results shown in Tables 1 to 4, it can be seen that the W / O emulsion ink of the present invention has greatly improved fixability to paper.

[0048]

The W / O emulsion ink of the present invention has a constitution in which at least one of the aluminum chelates represented by the structural formulas 1 to 2 is contained in the oil phase. The ink has improved fixability to paper without impairing the storage stability, safety and image characteristics. This prevents the printed matter and the operator's hands from being stained by the friction of the image.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-117564 (JP, A) JP-A-54-106305 (JP, A) JP-A-4-132777 (JP, A) JP-A-62 109873 (JP, A) JP-A-47-26202 (JP, A)

Claims (1)

(57) [Claims] 1. An oil phase of 10 to 50% by weight and an aqueous phase of 90 to 50%.
A W / O emulsion for stencil printing, comprising at least one of aluminum chelates represented by the following structural formula in the oil phase, comprising: a pigment, an emulsifier, an oil, a resin, and water. W / O for stencil printing characterized by the following
Type emulsion ink. Embedded image Embedded image (In the formula, R represents a C ₁₈ H ₃₅ group.)