JP3073817B2 - Emulsion ink for stencil printing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil printing emulsion ink, and more particularly to a stencil printing emulsion ink whose color tone can be arbitrarily adjusted.

[0002]

2. Description of the Related Art As is well known, a stencil printing method uses a stencil printing paper, and moves ink from one side of the stencil to the other through a perforated portion formed by making a stencil on the stencil. Printing is performed on the surface of a printing material such as paper. Generally, the color tone adjustment of printed materials with ink
This is done by adding a pigment of another color.
However, in this case, the pigment to be combined is not only in a desired color tone, but also, for example, depending on the combination thereof, color separation may occur and a uniform color tone or image may not be obtained. Need.
In addition, pigments and dyes may be added to the oil phase at the same time, but oils that can be used in water-in-oil emulsion inks contain non-volatile components when considered to be left on a printing press. This has the disadvantage that the printed matter may be fringed by the dye and oil of the image over time.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an emulsion ink for stencil printing which has been adjusted in color tone while eliminating the disadvantages of the prior art.

[0004]

The emulsion ink for stencil printing of the present invention comprises about 10 to 50% by weight of an oil phase and about 9 of an aqueous phase.
It consists W / O type emulsion consisting of 0-50% by weight, and a water-soluble colorant to the oil water phase, oil
It is characterized in that a pigment is contained in the phase .

[0005] To achieve the above object, the present inventors have
As a result of various studies, in the aqueous phase of the water-in-oil emulsion,
It was confirmed that by containing a coloring agent and a pigment in the oil phase, there was no color separation and an ink having a adjusted color tone could be obtained. The present invention has been made based on this.

Hereinafter, the present invention will be described in more detail. The oil phase is composed of a pigment, an oil component, an emulsifier, a resin and the like, and the aqueous phase is composed of water, a water-soluble resin, an electrolyte, a fungicide, an antioxidant, a water evaporation inhibitor and the like. Known components that do not inhibit the formation of an emulsion are used as these components.

As the oil component in the oil phase used in the present invention, conventionally known oil components can be applied, for example, liquid paraffin, spindle oil, light oil, kerosene, machine oil, mineral oil of lubricating oil; olive oil, rapeseed oil And vegetable oils such as castor oil and soybean oil. In the present invention, a synthetic oil can also be used. When using synthetic oils, various compounds are available. Representative synthetic vehicles include polyisobutylene, polyisobutenes, hydrogenated polydecenes, trimethylolpropane esters, neopentyl and pentaerythritol esters, di (2-ethylhexyl) sebacate, di (2-ethylhexyl) adipate, dibutyl phthalate , Fluorocarbons, silicates, silanes, esters of phosphorus-containing acids, liquid urea, ferrocene derivatives, hydrogenated synthetic oils, linear polyphenyls, siloxanes and silicones (polysiloxanes), butyl substitution Examples thereof include alkyl-substituted diphenyl ethers represented by bis (p-phenoxyphenyl) ethers and phenoxyphenyl ethers.

[0008] The emulsifier used in the present invention is preferably a nonionic surfactant, such as higher sorbitan fatty acid ester, higher polyoxyethylene sorbitan fatty acid ester, fatty acid monoglyceride, fatty acid diglyceride and higher alcohol, alkyl phenol, fatty acid and the like. Ethylene oxide adducts of the formula (I) are used alone or in combination of two or more of these having different HLB to prepare a highly stable emulsion.

The pigments that may be contained in the oil phase include:
Examples include organic and / or inorganic pigments such as furnace carbon black, lamp black, cyanine blue, cyanine green, lake red, titanium oxide, and calcium carbonate.

An appropriate amount of resin is added to the oil phase for the purpose of improving the stability of the emulsion ink over time and improving the binding property of the ink to paper. Such resins include, for example, alkyd resins, rosin-modified alkyd resins, polymerized castor oil, rosin, polymerized rosin, hydrogenated rosin, rosin ester, hydrogenated rosin ester, terpene resin, petroleum resin, rosin-modified phenolic resin, maleic acid Resins and rubber derivative resins.

As mentioned above, the emulsion ink for stencil printing of the present invention is free from color separation and contains a coloring agent in the aqueous phase in order to obtain a toned ink .
The greatest feature is that a pigment is contained in the oil phase .

The coloring agents usable in the present invention include:
Among the direct dyes, acid dyes and basic dyes of general dyes, those soluble in water, for example, C.I. I. Direct
Yellow 1, C.I. I. Direct Blue2,
C. I. Basic Yellow2 C.I. I. Acid
Yellow 17 and the like. In addition, iron tannins and C.I. I. Acid Blue22
Alternatively, a combination of 93 can be used.

As the evaporation inhibitor and anticoagulant, polyhydric alcohols such as ethylene glycol, sorbitol and glycerin, and polyethylene glycol are used.
Examples of antiseptic / antifungal agents include aromatic hydroxy compounds and chlorinated products thereof, salicylic acid, phenols, p
-Methyl oxybenzoate, ethyl p-oxybenzoate, and the like, sorbic acid, dehydroacetic acid, and the like are used.

The emulsion ink for stencil printing of the present invention can be produced, for example, by adding an emulsifier to the oil component and mixing the mixture, then adding a water phase solution to the mixture and emulsifying the mixture.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. The parts here are based on weight.

Example 1 Oil phase (coloring pigment) Furnace carbon black 4 parts (solvent) # 30 motor oil 21 parts (emulsifier 1) sorbitan sesquioleate 4 parts (emulsifier 2) polyoxyethylene sorbitan monolate 2 parts and aqueous phase (Water) Ion-exchanged water 56 parts (colorant) Tannic acid / iron gallate ink 0.74 parts C.I. I. Acid Blue 22 0.06 parts (antifreeze) ethylene glycol 12 parts (preservative and fungicide) 0.2 parts of ethyl p-oxybenzoate were added dropwise and stirred and emulsified to obtain an emulsion ink for stencil printing. Using this ink, printing was performed with a commercially available thermosensitive stencil printing machine (Ricoh, Preport SS955). Further, the stability of the ink was stored in a thermostat at 60 ° C. for one week and evaluated based on the presence or absence of oil bleeding. Table 2 summarizes the results
Shown in

Examples 2 and 3, Comparative Examples 1 and 2 In accordance with the prescription shown in Table 1, stencil printing inks were prepared in the same manner as in Example 1, and the same evaluation was performed. Table 1 shows the evaluation results.

[0018]

[Table 1]

[0019]

[Table 2]

[0020]

According to the emulsion ink for stencil printing of the present invention, the aqueous phase contains a colorant, and the oil phase contains
By containing pigment, there is no color separation,
Further, a toned ink can be obtained.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiro Koike 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Hitoshi Ueda 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Naoto Shimoda, Inventor 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Takashi Sugawara 3-1 Shimido, Nakanameki, Shibata-cho, Shibata-gun, Miyagi Prefecture Tohoku Ricoh Co., Ltd. (72) Keisuke Asada, Inventor 3-1 Shinmei-do, Nakaname Ichimoji, Shibata-cho, Shibata-gun, Miyagi Prefecture 3-1 Tohoku Ricoh Co., Ltd. (56) References Patent 42414 (JP, C1) Int.Cl. ⁷ , DB name) C09D 11/00-11/20

Claims (1)

(57) [Claims] An oil phase of about 10 to 50% by weight and an aqueous phase of about 90 to 90% by weight.
A water-in-oil emulsion consisting of 50% by weight,
The water phase contains a water-soluble colorant, and the oil phase contains
Emulsion ink for stencil printing containing pigment