JP3314962B2 - Emulsion ink for stencil printing and stencil printing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a stencil printing emulsion ink, and more particularly to a stencil printing emulsion ink excellent in ink drying property and a stencil printing method suitable for continuous printing using the same.

[0002]

2. Description of the Related Art Stencil printing is used in a wide range of fields because of easy production of a printing plate. However, it takes time to dry the ink after stencil printing, and if you hold the printed paper etc. in your hand immediately after printing, the ink may transfer to your hand or the printed paper etc. may be overlaid during continuous printing. When combined, ink set-off occurs, and there is a problem that these phenomena are remarkable especially on postcard paper having poor ink permeability.
The reason for this is that emulsion ink is used as conventional stencil printing ink from the point of on-machine stability and the like. Therefore, the drying of the ink is significantly reduced on paper having poor ink permeability.

[0003] Further, there is a disadvantage that the permeation state of the ink and the evaporation rate of water are easily changed depending on the state of leaving the emulsion ink. As described above, in stencil printing, the dryness of the ink significantly changes depending on the type of the printing medium such as paper and the environmental conditions, so that conventionally, a compromise between the stability of the emulsion ink and the ink permeability has been empirically determined. The water content and the like of the emulsion ink were determined by selection.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, to improve the drying and fixing properties of ink to a printing medium, and to prevent set-off of printed matter. An object of the present invention is to provide a printing emulsion ink and a stencil printing method using the same.

[0005] A first invention of the present application is the emulsion ink comprising an oil phase and an aqueous phase, wherein the oil phase and / or the aqueous phase contains a silicone oil and a uniformly dispersed heat-fusible component. It is an emulsion ink for stencil printing. According to a second aspect of the present invention, there is provided an emulsion ink comprising an oil phase and an aqueous phase, wherein the oil phase and / or the aqueous phase is dispersed in a silicone oil and uniformly.
A stencil printing emulsion ink characterized by containing a thermoset component.

A third invention of the present patent application may be printed with the ink by stencil printing using the stencil printing emulsion ink
After transferring to the body , the resulting printed matter is subjected to heat treatment
A stencil printing method characterized by fixing the ink to a printing medium .

In the present invention, as the emulsion ink, a water-in-oil (W / O) type or an oil-in-water (O / W) emulsion ink can be used. . Water-in-oil (W / O) emulsion inks are preferred from the viewpoint of long-term storage stability. The water-in-oil emulsion ink is, for example, 1
It can be produced by gradually adding 90 to 30% by weight of an aqueous phase component to 0 to 70% by weight of an oil phase component and emulsifying the mixture.

[0008] The hot-melt component used in the present invention is uniformly dispersed and contained in at least one of the oil phase and the aqueous phase of the emulsion ink. Examples of the heat fusible component include polymers and copolymers such as polystyrene, acrylic resin, polyester, polyethylene and polyamide, low molecular weight polyethylene, and polypropylene. The temperature is preferably in the range of 40 to 100 ° C. from the viewpoint of the amount of heat used in the heat treatment.
The range of 0-70 degreeC is more preferable. The amount of addition
From the viewpoints of the fixing property of the ink, the viscosity, and the storage stability, the amount is preferably in the range of 3 to 50% by weight based on the total amount of the ink.

By dispersing the hot-melt component in the emulsion ink, the printed material is subjected to a heat treatment with a heating roll or an iron, so that the ink layer can be reliably fixed to the printing medium, and drying and drying of the ink can be performed. The fixation can be improved and set-off can be prevented.

The thermosetting component used in the present invention is contained in at least one of the oil phase and the aqueous phase of the emulsion ink in a uniformly dispersed state. Examples of the thermosetting component include an epoxy resin, a phenol resin, and a urethane resin. The amount of the thermosetting component is 3 to 60 with respect to the total amount of the ink from the viewpoints of ink fixing property, viscosity, and shelf stability. % By weight, more preferably from 5 to 40% by weight. By dispersing and containing the thermosetting component in the emulsion ink, the ink layer can be reliably fixed by subjecting the printed matter to heat treatment with a heating roll or iron, improving the drying and fixing of the ink, Transfer can be prevented.

The silicone oil used in the present invention is contained in either the oil phase or the aqueous phase of the emulsion ink. Examples of the silicone oil include dimethyl silicone oil and methyl phenyl silicone oil.
96, KF-50, KM-742 (emulsion type) and the like can be used. When adding to the aqueous phase side, disperse the silicone oil in the aqueous phase in advance,
This is gradually added and dispersed in the oil phase. When adding to the oil phase side, silicone oil is dissolved or uniformly dispersed in one component in the oil phase and added.

When added to the oil phase, the viscosity of the silicone oil is preferably in the range of 1 to 1,000 cps. This is because the viscosity of the emulsion ink greatly changes depending on the viscosity of the silicone oil. When a high-viscosity silicone oil is used, the viscosity of the emulsion ink itself becomes high, and the fluidity of the ink decreases. The addition amount of the silicone oil is preferably in the range of 1 to 20% by weight from the viewpoints of the shelf stability of the emulsion ink, the viscosity, the leveling property (the wettability of the ink to the printing medium), and the like.
A range of 5 to 10% by weight is more preferable. By adding silicone oil to the emulsion ink, it is possible to prevent the offset phenomenon (transfer phenomenon of the ink to the surface of the heat fixing roll or the iron surface) that occurs during the heat treatment with a heating roll or an iron, and to improve the ink leveling. Transfer of excess ink to the printing medium can be prevented.

The oil phase component of the emulsion ink of the present invention contains a solvent, a resin, a colorant, an emulsifier, and the like, and the aqueous phase component contains a water-soluble resin, an electrolyte, a fungicide, an acid value, if necessary. Water-soluble additives such as inhibitors can be included. As the solvent, petroleum-based solvents are used, for example,
Ink Solvent 240 (boiling point 242 to 260 ° C., manufactured by Mitsubishi Petroleum Corporation), Nisseki Isosol 400 (boiling point 206 to 2
57 ° C, manufactured by Nippon Oil Co., Ltd., Nisseki No. 4 solvent (boiling point 2
06-267 ° C., manufactured by Nippon Oil Co., Ltd.). Examples of the coloring agent include generally used furnace carbon black, lamp black, pliant fast scarlet, and the like.

The resin component is usually added for the purpose of dispersing the colorant, fixing the colorant to the printing medium, and the like. In the present invention, the fixing of the colorant to the printing medium is performed by heat melting. For the resin component, dispersibility of the colorant, compatibility or uniform dispersibility of the heat-meltable component and the thermosetting component are required for the resin component or the thermosetting component. Maleic resin, petroleum resin,
Alkyd resins and the like.

As an emulsifier for producing a water-in-oil emulsion ink, a nonionic surfactant is preferably used, and sorbitan higher fatty acid esters such as sorbitan monolaurate and sorbitan monopalmitate, oleic acid monoglyceride, olein Examples include fatty acid monoglycerides such as acid diglycerides, higher alcohols, alkylphenols, ethylene oxide adducts such as fatty acids, and the like. Two or more of these low and high HLBs are combined to prepare an HLB to obtain a stable emulsion ink. be able to.

In the present invention, a printed matter printed using an emulsion ink containing a hot-melt component or a thermosetting component is subjected to a heat treatment using, for example, a heating roll or an iron. The heat treatment temperature (the temperature of the heating roll or the iron) is appropriately determined depending on the type of the thermoplastic resin or the thermosetting resin used. The heat treatment can reliably fix the ink solids such as the colorant, the heat-meltable component or the thermosetting component on the surface of the printing medium to the printing medium, and use printing paper excellent in ordinary permeability. In this case, of course, even when a postcard having poor ink permeability is used, continuous printing without set-off can be suitably performed.

[0017]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the invention thereto. In addition,
Parts in the examples mean parts by weight. Example 1

At the above ratio, the component A is first mixed and thoroughly kneaded with a three-roll mill, and then the component B is sufficiently stirred, mixed and added. While gradually adding an aqueous solution consisting of, the mixture was stirred with a stirrer and emulsified to prepare a water-in-oil emulsion ink.
Using the obtained emulsion ink, stencil printing was performed by a stencil printing machine (Risograf RC115D, manufactured by Riso Kagaku Kogyo KK). Next, the obtained printed matter was passed through a heating roll having a surface temperature of about 180 ° C. at a speed of 3 m / min to perform a heat treatment. Drying property of the ink of the obtained printed matter,
Fixing properties, standing stability, and offset properties were examined by the following methods, and the results are shown in Table 1.

(1) Drying property: Evaluated by the cured state of the ink transfer surface by a touch finger test. (2) Fixing property: Evaluated by the state of fixation to printing paper by a touch test. (3) Storage stability: The prepared emulsion ink was left at room temperature for 3 months, and the uniform state (stability) of the emulsion was examined. (4) Offset property: evaluated by occurrence of offset phenomenon on a heating roll (or iron).

Embodiment 2 In Example 1, an emulsion ink was prepared and stencil printing was performed in the same manner as in Example 1 except that the components A, B, and C were respectively replaced with the above components, and an iron (surface: (Fluororesin processing) for 5 seconds to perform heat treatment. The obtained printed matter was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Embodiment 3 In Example 1, an emulsion ink was prepared and stencil printing was performed in the same manner as in Example 1 except that the components A, B, and C were each replaced with the above-described components. The printed matter was evaluated by using
It was shown to.

Embodiment 4 In Example 1, an emulsion ink was prepared and stencil printing was performed in the same manner as in Example 1 except that the components A, B, and C were respectively replaced with the above components. The results are shown in Table 1.

Comparative Example 1 In Example 1, a silicone oil and styrene-
An emulsion ink was prepared in the same manner as in Example 1 except that the acrylic resin was not used, and a printed matter was obtained. The evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1. Comparative Example 2 An emulsion ink was prepared and printed matter was obtained in the same manner as in Example 1 except that the silicone oil was not used, and evaluation was performed in the same manner as in Example 1. It was shown to. Comparative Example 3 In Example 1, an emulsion ink was prepared and a printed matter was obtained in the same manner as in Example 1 except that the styrene-acrylic resin was not used, and the evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

[0024]

[Table 1] Table 1 shows that the printed matter printed using the emulsion ink of the present invention is excellent in drying property, fixing property and offset property of the ink, and also excellent in storage stability of the ink.

[0025]

According to the first and second aspects of the present invention, the oil phase and / or the water phase of the emulsion ink is
Thermally fusible component or thermosetting that is uniformly dispersed and contained
Because silicone oil is contained with the components,
The printing medium is heated by heating the printing medium after stencil printing.
Can reliably fix the ink layer on the surface, improve ink drying properties such as postcards with poor ink permeability, and prevent ink set-off during continuous printing and blocking after printing. it can be, further, the pressure
In addition to preventing the occurrence of offset phenomenon during heat treatment
In addition, because the leveling property is improved,
Can be eliminated. According to the third invention of the present application,
The ink layer can be reliably fixed to the printing medium.

[0026]

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C09D 11/02 C09D 11/10

Claims (3)

(57) [Claims] 1. An emulsion ink comprising an oil phase and an aqueous phase, wherein the oil phase and / or the aqueous phase is a silicone ink.
To contain N'oiru and uniformly dispersed hot-melt component
Stencil printing emulsion ink which is characterized in that that. 2. An emulsion ink comprising an oil phase and an aqueous phase, wherein the oil phase and / or the aqueous phase is a silicone ink.
To contain N'oiru and uniformly dispersed thermosetting component
Stencil printing emulsion ink which is characterized in that that. 3. A stencil printing using the emulsion ink for stencil printing according to claim 1 or 2, wherein the ink is marked.
A stencil printing method, wherein after transferring to a printing body , the obtained printed matter is subjected to a heat treatment to fix the ink on the printing body .