JP2802923B2 - Ink media for printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention relates to an ink medium for a printer used in a method of transferring and recording by utilizing a magnetic attraction force when heated and melted.

<Prior Art> Recently, many non-impact printing systems using magnetic ink have been proposed, and magnetic inks used in the non-impact printing system have been developed.

As an example of the above magnetic ink, for example,
No. 215088. This ink has an organic substance showing thermoplasticity and a particle size of 10 on the surface of the support layer.
A thermoplastic magnetic ink layer containing ferromagnetic fine particles of {300} is formed.

In the ink medium for a printer formed as described above, ferromagnetic fine particles of a magnetic fluid are used as ferromagnetic fine particles of a thermoplastic magnetic ink, and an attempt has been made to perform printing by flying the ink by a magnetic attraction force. Cannot print.

<Problems to be Solved by the Invention> In order to cause the thermoplastic magnetic ink melted on the surface of the heat-resistant base material to fly by magnetic attraction, the magnetic force acting on the magnetic ink is increased and the kinematic viscosity of the magnetic ink is reduced. More importantly, it is necessary to lower the surface tension of the ink in order to reduce the energy for forming the ink droplets.

In general, a surfactant can be added to lower the surface tension of the liquid. However, to lower the surface tension of a water-based liquid such as a thermoplastic magnetic ink, a fluorine-based surfactant may be used. It has been concluded that a surfactant having the following structure is the best, and that the ink has the best flight characteristics.

An object of the present invention is to include a fluorine-based surfactant having a certain special structure in a thermoplastic magnetic ink layer, so that a thermoplastic magnetic ink that has been melted by heat is caused to fly by a magnetic attraction force and a recording is performed. An object of the present invention is to provide an ink medium for a printer, which is suitably used for a printing apparatus which has not been conventionally used, which is transferred and recorded on paper.

<Means for Solving the Problems> Further specifically describing the present invention, an ink medium for a printer comprising a thermoplastic magnetic ink layer provided on the surface of a heat-resistant base material, wherein the thermoplastic magnetic ink layer is The present invention relates to an ink medium for a printer, comprising at least a binder, a magnetic powder, and 0.03 to 5% by weight of a fluorine-based surfactant based on the binder.

The structure of the fluorine-based surfactant is represented by CH _{2 in the} general formula.
ＣC (R ₁ ) R ₂ (where R ₁ is H or CH ₃ , R ₂ is a group containing a perfluoroalkyl group having at least one carbon atom)
And a hydrophobic lipophilic vinyl monomer represented by the formula: CH ₂ ＣC (R ₃ ) R ₄ (where R ₃ is H or CH ₃ , R ₄ is a group containing an alkyl group) The present invention relates to the printer ink medium described above, which is a random copolymer or a block copolymer with a vinyl monomer.

<Example> Hereinafter, the ink medium for a printer of the present invention will be described in detail.

FIG. 1 is an enlarged sectional view showing a use state of an ink medium for a printer of the present invention.

The ink medium 1 of the present invention has a thermoplastic magnetic ink layer 3 on one surface of a heat-resistant base material 2, and the thermoplastic magnetic ink layer 3 is locally applied by a thermal head facing the other surface of the heat-resistant base material 2. Then, the thermoplastic magnetic ink layer 3 is heated and melted, and the heated and melted thermoplastic magnetic ink layer 3 is attracted by the magnetic force of the permanent magnets 6 facing each other across the recording paper 5 and is transferred onto the recording paper 4.

FIG. 2 is an enlarged detailed view of the ink medium 1 for a printer according to the present invention. Basically, a thermoplastic magnetic ink layer 3 is formed on the surface of a heat-resistant base material 2.
Has a binder agent 3a and a magnetic powder 3b, and the magnetic powder 3b
A fluorine-based surfactant is contained in the binder agent 3a in which is dispersed.

As the heat-resistant substrate 2, for example, a plastic film such as polyester, polyethylene, polycarbonate, or polyamide having a thickness of about 1 to 20 μm, cellophane, sulfuric acid paper, or condenser paper can be used.

The thickness of the thermoplastic magnetic ink layer 3 formed on the surface of the heat-resistant base material 2 is preferably 2 to 20 μm, and the thermoplastic temperature of the thermoplastic magnetic ink is preferably in the range of 40 to 200 ° C.

Examples of the binder agent 3a constituting the thermoplastic magnetic ink layer 3 include carnauba wax, candelilla wax, montan wax, beeswax, natural wax such as lanolin, petroleum wax such as paraffin wax and microcrystalline wax, oxide wax, and ester wax. , Synthetic waxes such as polyethylene wax, lauric acid, stearic acid, myristic acid, palmitic acid,
Higher fatty acids such as behenic acid, stearyl alcohol, higher alcohols such as behenyl alcohol, cetyl palmitate, higher fatty acid esters such as cetyl stearate,
Amides such as lauric amide, stearic acid amide, oleic acid amide, ester gum, rosin or derivatives thereof, phenolic resin, terpene resin, xylene resin, polystyrene resin, petroleum resin, polyester resin, epoxy resin Thermoplastic resins such as resin, polyurethane resin, polyacrylic resin, polyvinyl chloride resin, cellulose resin, polyvinyl alcohol resin, polyamide resin, ethylene vinyl acetate copolymer resin, ethylene-ethyl acrylate copolymer resin , Nitrile rubber, acrylic rubber, styrene-butadiene rubber, natural rubber, and other elastomers, and these can be used alone or in combination of two or more.

The fluorine-based surfactant contained in the ink medium for a printer of the present invention has a structure represented by a general formula CH ₂ ＣC (R ₁ ) R ₂ (where R ₁
Is a hydrophobic oleophobic vinyl monomer represented by H or CH ₃ , and R ₂ is a group containing at least one or more perfluoroalkyl groups) and CH ₂ ＣC (R ₃ ) R ₄ (where R ₃ is H, CH ₃ and R ₄ are groups containing an alkyl group) and a random copolymer or a block copolymer with a hydrophobic lipophilic vinyl monomer represented by the following formula:

As the above-mentioned hydrophobic oleophobic vinyl monomer, those represented by the following structural formula can be used.

CH ₂ = CHC ₆ F ₁₃ CH ₂ = CHCOOCH ₂ C ₇ F ₁₅ CH ₂ = CHCOOCH ₂ CH ₂ C ₆ F ₁₃ CH ₂ = CHCOOCH ₂ CH ₂ C ₈ F ₁₇ CH ₂ = CHOCOC ₇ F ₁₅ CH ₂ = CHCOOCH _{2 CH 2 N (C 3 H 7} ) SO 2 C 8 F 17 CH 2 = C (CH 3) COOCH 2 CH 2 C 6 F 13 CH 2 = C (CH 3) COOCH 2 CH 2 N (C 3 H 7) SO ₂ C ₈ F ₁₇ On the other hand, as the hydrophobic lipophilic vinyl polymer, those represented by the following structural formula can be used.

_{CH 2 = CHCOOC 12 H 25 CH} 2 = CHCOOC 16 H 33 CH 2 = C (CH 3) COOC 12 H 25 CH 2 = CHC 16 H 33 CH 2 = C (CH 3) C 10 H 21 CH 2 = CHOCOC 10 H ₂₁ The fluorine-based surfactant contained in the printer ink medium of the present invention will be described in more detail.As a random copolymer type, a hydrophobic oleophobic monomer containing a perfluoroalkyl group, and for imparting compatibility to the polymer Hydrophobic lipophilic monomers are randomly polymerized, and examples of such a fluorine-based surfactant include Surflon S-381, S-382, S-581, SC-101, and SC-105 (all manufactured by Asahi Glass). Can be mentioned.

On the other hand, as the block copolymer type, a hydrophobic oleophobic segment polymerized with a hydrophobic oleophobic monomer containing a perfluoroalkyl group and a polymer compatible segment polymerized with a hydrophobic lipophilic monomer for imparting compatibility to the polymer are formed as a block. In the form of a copolymer, such fluorine-based surfactants include, for example, Modiper F11
0, F140, F150 and F210 (all manufactured by Nippon Oil & Fat).

In the ink medium for a printer of the present invention, the addition amount of the fluorine-based surfactant to the binder agent is 0.03 to 5% by weight, preferably 0.05 to 1% by weight, and 0.1% by weight or less. Since the surface tension of the ink medium is not sufficiently reduced, more energy is required to generate droplets during printing. Conversely, when the content is 5% by weight or more, the surface tension of the ink medium does not decrease below a certain value or more, so that the generation energy of droplets at the time of printing does not drop below a certain value and a further effect can be expected. Absent.

Examples of the magnetic powder 3b constituting the thermoplastic magnetic ink layer 3 include metals of ferromagnetic elements such as iron, cobalt, and nickel, alloys containing these elements as main components, and magnetite, γ-hematite, and ferrite. And the like.

The particle size of the magnetic powder 3b is preferably 0.01 to 5 μm, and the content of the magnetic powder 3b in the thermoplastic magnetic ink layer 3 is preferably 30 to 90% by weight.

In the thermoplastic magnetic ink layer 3, a coloring agent such as a dye or a coating material is added to adjust the color density of the ink. However, when the magnetic powder is black, it is necessary to add a dye or a pigment. Absent.

Hereinafter, the ink medium for a printer of the present invention will be described more specifically with reference to examples.

Example 1 Magnetite (average particle diameter 0.2 μ, coercive force 70 Oe) 50.0 Paraffin wax (mp 69 ° C.) 28.5 Carnauba wax 17.0 Ethylene-vinyl acetate copolymer (vinyl acetate content 28%) 4.0 Surflon SC-105 (Asahi Glass) The addition amount of 0.1 fluorine-based surfactant is a pure content conversion.

Example 2 Same as Example 1 except for the type and amount of the fluorine-based surfactant. The types and amounts of the fluorosurfactants are shown below.

Surflon SC-105 (Asahi Glass) 0.1 Example 3 Surflon SC-105 (Asahi Glass) 0.5 Example 4 Surflon S-581 (Asahi Glass) 0.5 Example 5 Modiper F140 (Nippon Oil & Fat) 0.5 Comparative Example 1 No additive Comparison Example 2 Surflon SC-105 (manufactured by Asahi Glass) 0.005 Comparative Example 3 Surflon SC-105 (manufactured by Asahi Glass) 0.01 The above ink components were heated and stirred at 100 ° C., and then uniformly dispersed using a roll mill. The obtained ink was applied to the surface of a 4 μm thick polyester film using a wire bar to obtain an ink medium for a printer of the present invention having an 8 μm thick ink layer.

Using a recording device incorporating a permanent magnet having a maximum energy product of 20MGOe in the platen roller portion of the thermal printer PC-PR201T manufactured by NEC Corporation, the obtained ink medium for the printer was set to 400 μm between the recording paper and the ink layer, Printing was performed at a printing speed of 35 characters / second.

For recording paper, commercially available PPC paper (Beck smoothness 40 seconds)
And bond paper (Beck smoothness: 10 seconds).

Then, the prints were evaluated for blurring and cutting of the edges, and those having no blurring were observed. ◎ Those having almost no blurring were observed. Is not clear Δ is marked as unsatisfactory edge and is shown in Table 1. As described in Table 1, in Examples 1 to 5, clear prints with sharp edges and no blurring were obtained on PPC paper, and similar prints were obtained on bond paper. On the other hand, as shown in Table 1, in all of Comparative Examples 1 to 3, the results were not satisfactory for both the PPC paper and the bond paper.

The surface tension was measured at 120 ° C. using a CBVP surface tensiometer (A-3 manufactured by Kyowa Interface Science).

<Effects of the Invention> As described above, the ink medium for a printer of the present invention contains a magnetic powder and a fluorinated surfactant in a thermoplastic magnetic ink layer, so that the surface energy of the ink at the time of hot melting is low, When a magnetic attraction force is applied during thermal transfer,
The melted thermoplastic magnetic ink flies at a low energy and is transferred and printed on the recording paper. For this reason, the ink medium for a printer of the present invention is not affected by the surface condition of the recording paper, and has a sharp and sharp edge on paper having low surface smoothness such as bond paper as well as smooth paper such as PPC paper. No clear printing is possible.

Further, since the ink medium for a printer of the present invention can perform printing even when the recording medium and the ink medium for a printer are not in contact with each other, there is no problem such as background contamination as seen in the conventional thermal transfer.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is an enlarged sectional view showing a use state of the ink medium for a printer of the present invention, and FIG. 2 is an enlarged detailed view of the ink medium for a printer of the present invention. It is.

Claims (2)

(57) [Claims] An ink medium for a printer comprising a heat-resistant base material provided with a thermoplastic magnetic ink layer on a surface thereof, wherein the thermoplastic magnetic ink layer contains at least a binder, a magnetic powder and a binder. An ink medium for a printer, comprising 0.03 to 5% by weight of a fluorine-containing surfactant. 2. The structure of a fluorine-based surfactant represented by the general formula: CH ₂ ＣC (R ₁ ) R ₂ (where R ₁ is H or CH ₃ , R ₂ is a perfluoroalkyl group having at least one carbon atom). And a hydrophobic oleophobic vinyl monomer represented by the formula: CH ₂ ＣC (R ₃ ) R ₄ (where R ₃ is H or CH ₃ ,
R ₄ is an ink medium for the printer according to claim 1 which is a random copolymer or a block copolymer of a hydrophobic oleophilic vinyl monomer represented by the group) containing an alkyl group.