JP3428689B2 - Ink jet recording method and apparatus - Google Patents

Description

Detailed Description of the Invention

[Background of the Invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intermediate transfer type ink jet recording method and an apparatus for carrying out the method. More specifically, the ink image is formed on an intermediate transfer medium by the ink jet recording method and then the ink image is formed. The present invention relates to an ink jet recording method and an apparatus for carrying out the same, which comprises transferring the image onto a recording medium.

[0002]

2. Description of the Related Art The ink jet recording system is excellent in that the mechanism is simple and noise is not generated. However, in addition to the problem that the printing state changes due to the difference in the recording medium, for example, the difference in the paper quality of the recording paper, there is the problem that the image of the undried portion of the ink image is disturbed when the recording medium is discharged.

A recording apparatus that has attempted to solve such a problem is an intermediate transfer system in which an ink image is once formed on an intermediate transfer medium by an ink jet recording system and then the ink image is transferred from the intermediate transfer medium onto the recording medium. Has been proposed (US Pat. Nos. 4,538,156 and 5,099,256). In this method, the recording head can be arranged separately from the recording paper. As a result, it is possible to prevent clogging of the recording head due to contact that occurs when the recording head is arranged close to the recording paper and adhesion of paper dust generated from the recording paper.

In such an apparatus, it is satisfactory that the desired ink image is accurately formed on the intermediate transfer medium and that the ink image is efficiently transferred from the transfer medium to the recording medium at a low pressure. It must be.

In the former case, if the ink droplets ejected on the intermediate transfer medium are unduly spread or flow on the intermediate transfer medium and the position or shape of the ink droplets is largely changed, the formed print may be formed. Will be disturbed. In the present specification, such a phenomenon may be referred to as “repellency” of ink. For example, FIG. 9 is a diagram schematically showing a state in which a straight line (line) is printed by a dot group. If the dot group as shown in FIG. 9A is formed on the intermediate transfer medium, good printing can be obtained on the recording medium. On the other hand, FIG.
As shown in (b), when a "repelling" phenomenon occurs in which dots are unreasonably spread or flow from the area where dots are originally supposed to be formed, which is indicated by a broken line, and a "repelling" phenomenon occurs, Good print cannot be obtained on the recording medium. Regarding the latter, when the ink image formed on the intermediate transfer medium is transferred to the recording medium, the ink image may remain on the intermediate transfer medium or a large pressure may be required for the transfer, so It will not be possible to print with good quality.

For example, Japanese Patent Laid-Open No. 1-146750 discloses that
A method of forming a thin film of glycerin on a transfer medium and forming an ink image with an oil-based ink on the thin film is disclosed. According to this method, accurate ink image formation and efficient transfer of the ink image to the recording medium at a relatively low pressure can be performed.

However, the present inventors have confirmed that when this method is carried out using an aqueous ink composition containing water as a main solvent, efficient transfer may not be carried out, unlike the case of oil-based ink. is doing.

Further, in the conventional recording method, it seems that a linear load (load per unit length) of about 2.5 kg / cm is required to transfer the ink image onto the recording medium. If the transfer can be performed at a lower pressure, it is considered that there is no limitation on the material forming the device and a lighter and smaller device can be realized.

[Outline of the Invention]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an intermediate transfer type ink jet recording method capable of obtaining efficient printing when an aqueous ink composition is used.

[0010]

Therefore, the intermediate transfer type ink jet recording method according to the present invention has an HLB value of 7-8.
A step of ejecting the ink composition onto an intermediate transfer medium having a surface carrying a surfactant to form an ink image, and the ink image on the intermediate transfer medium having a linear load of 0.5 kg on the recording medium. / Cm or less and the step of transferring at a pressure of less than. Further, the intermediate transfer type inkjet recording apparatus according to the present invention discharges the intermediate transfer medium having a surface having a surfactant having an HLB value of 7 to 8 and a droplet of an ink composition to perform the intermediate transfer. Recording means for forming an ink image on the medium, and transfer means for transferring the ink image to the recording medium by pressing the ink image on the intermediate transfer medium and the recording medium with a pressure of a linear load of 0.5 kg / cm or less. Is included.

[Detailed Description of the Invention] (Surfactant) In the recording method according to the present invention, HLB (hydrophili) is used.
A surfactant having a c-lipophilic balance) value of 7 to 8 is used. Specific examples of the surfactant include a cationic surfactant (for example, an aliphatic amine salt and its quaternary ammonium salt, an aromatic quaternary ammonium salt, a heterocyclic quaternary ammonium salt, etc.), an anionic surfactant ( For example, alkyl carboxylate, alkyl ether carboxylate, alkylbenzene sulfonate, alkylnaphthalene sulfonate, dialkyl sulfosuccinate, higher alcohol sulfate ester salt, alkyl ether sulfate salt, alkyl ether phosphate ester salt, alkyl phosphate salt. Ester salts), nonionic surfactants (eg, ethers such as alkyl and alkylallyl polyoxyethylene ethers, ether esters such as polyoxyethylene ethers of glycerin ester, polyethylene glycol fatty acid esters, etc. Ethers, and nitrogen-containing compounds such as fatty acid alkanolamides) amphoteric surfactants (e.g., carboxymethyl betaine, aminocarboxylates,
Imidazoline derivative, etc.), silicone-based surfactant,
Fluorine-based surfactants (in particular, those in which all hydrogen atoms in the hydrocarbon chain are replaced with fluorine atoms are preferable) and the like. Commercially available products can be used as these surfactants. As a specific example, Neocor YSK (HLB value 11, the value in parentheses is HL.
B value), Hitenol N-17 (14) (above, an anionic surfactant manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), Nogain EA
-50 (6), EA-140 (14), Sorgen 30
(4), Epan 420 (9), 740 (13) (above, nonionic surfactant manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.),
L-7001 (7), 7602 (8), 7604
(13), Fz-2171 (2), and 2163 (1).
3), the same 2164 (8) (above, silicone surfactant of Nippon Unicar Co., Ltd.), FC-430 (12).
(Sumitomo 3M Fluorosurfactant) and the like.

(Recording Method and Apparatus) An inkjet recording method and apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an example of an inkjet recording apparatus according to the present invention, and FIG. 2 is a sectional view in the X direction thereof.
This apparatus is configured to include a transfer drum 1 which is an intermediate transfer medium, an inkjet recording unit (inkjet recording head) 2 and a pressure roller 3 which are arranged around the transfer drum 1, and a transfer drum rotating direction of the recording head 2. A surfactant coating device 4 is provided on the upstream side.

The transfer drum 1 is composed of an elastic layer 11 on the surface and an internal drum 12. The elastic layer 11 is preferably made of a rubber material, and it is particularly preferable that the elastic layer 11 be a material that easily peels off an ink image and has heat resistance. Examples of preferable rubber materials include silicone rubber, fluorosilicone rubber, phenyl silicone rubber, fluororubber, chloroprene rubber, nitrile rubber, ethylene propylene rubber, natural rubber, styrene rubber, isoprene rubber, butadiene rubber, ethylene / propylene / butadiene polymer. , Nitrile butadiene rubber and the like. In particular, silicone rubber, fluorosilicone rubber, phenyl silicone rubber, fluororubber and chloroprene rubber are preferable.

The recording head 2 selectively ejects ink droplets in accordance with a print signal, and is, for example, an ink jet recording head using a piezoelectric element. In the apparatus of FIGS. 1 and 2, a recording head having nozzles over almost the entire width of the transfer drum 1 was used.

The pressure roller 3 is preferably a roller made of metal, and is pressed against the transfer drum 1 by pressure applying means (not shown).

Further, the surfactant coating device 4 includes a surfactant 41 contained in a container 40 and the surfactant 4
1, a liquid-absorbent wick 42, one end of which is immersed in the elastic layer 11, and a part of which is in contact with the elastic layer 11. As shown in the drawing, the wick is configured to have substantially the entire width of the transfer drum 1, or at least the entire width of the printing area, and is preferably made of felt material.

In the above apparatus, printing is performed as follows. First, the surfactant 41 is pulled up by the capillary phenomenon of the wick 42, and is applied to the surface of the elastic layer 11 by the wick 42. An ink image 5 is formed on the application surface by the inkjet recording head 2. Due to the presence of the surfactant, the ink image 5 is formed at an accurate position without unduly spreading or flowing and the position thereof being largely changed. This ink image is carried to the area facing the pressure roller 3 as the transfer drum 1 rotates, and is transferred onto the recording medium 6. At this time, due to the presence of the surfactant, the ink image 5 is completely separated from the intermediate transfer drum 1. This makes it possible to perform printing without transfer residue. The transfer drum 1 that has completed the transfer process comes into contact with the surfactant coating device 4 again to clean the surface thereof and prepare for the next image formation. Needless to say, it is preferable that the surface active agent is applied to the entire area where the ink image is formed.

Further, according to another preferred embodiment of the present invention, the surfactant coating device 4 may be configured as shown in FIG. That is, instead of the wick 42 shown in FIG. 2, the surfactant may be applied using an applying roller 43 having an absorbing layer (preferably made of sponge) 44. In this device, a regulating blade 45 may be provided to regulate the amount of surfactant absorbed in the absorption layer 44.

Further, according to another preferred embodiment of the present invention, when the surfactant is solid at room temperature, the surfactant coating device 4 may be configured as shown in FIG.
That is, in the apparatus shown in FIG. 4, the solid surfactant 41 may be supported by the indicating member 50 while being brought into contact with the elastic layer 11 by the pressing spring 51 to apply the surfactant. In this configuration, the surface of the transfer drum 1 after transfer is cleaned by the cleaner blade 52.

According to another aspect of the present invention, the surfactant may be preliminarily supported on the elastic layer by kneading the elastic layer in advance. Specifically, a rubber material is mixed with a surfactant and then vulcanized to form an elastic layer. According to a more preferable aspect, it is preferable that the rubber material and the surfactant have low compatibility. If the rubber material and the surfactant are not compatible with each other, it is considered that the surfactant is supplied to the surface of the elastic layer, albeit little by little, so that a good surface state is always maintained. The preferable addition amount of the surfactant is about 1 to 15% by weight, more preferably 3 to 10% by weight with respect to the rubber material.
It is about% by weight.

In the present invention, the linear load is 0.5 kg / c.
It is possible to transfer the ink image on the intermediate transfer medium onto the recording medium with a pressure of about m or less. In the conventional method as described above, it is difficult to transfer the ink image at such a low pressure without leaving it on the intermediate transfer medium. In the apparatus according to the present invention, since the transfer process can be performed at such a low pressure, the strength required for each member is not so large, and it is advantageous in that the size of the entire apparatus can be reduced, for example.

According to a preferred embodiment of the present invention, the fixing of the ink image transferred onto the recording medium may be ensured by subsequently heating the ink image and optionally applying further pressure.

According to a further preferred aspect, it is preferable to heat the ink image by providing means for heating the ink image formed on the intermediate transfer medium. FIG. 5 is a perspective view of an example of an apparatus provided with a heater 7 as heating means, and FIG. 6 is a sectional view in the X direction thereof.

In this apparatus, the printing is performed as follows. First, the pressure releasing means 31 keeps the pressure drum 3 out of contact with the transfer drum 1. Then, in the same manner as described above, the surfactant is applied onto the transfer drum 1 by the surfactant applying device 4. In this device, the surfactant coating device 4 can be placed in a state where it is not in contact with the transfer drum 1 (specifically, it can be moved as shown by an arrow B in FIG. 6), After the application of the surfactant, the transfer drum 1 is brought into a non-contact state. Subsequently, the ink image 5 is formed on the transfer drum 1 while reciprocally scanning the inkjet recording head 2 along the carriage 20. The ink image 5 formed on the transfer drum 1 is heated by the heating means 7, and the volatile solvent component contained therein is evaporated. As a result, the surface of the ink image 5 becomes viscous and is more easily transferred to the recording medium. That is, this ink image is transferred by being pressed against the recording medium 6 between the pressure drum 3 and the transfer drum 1 by the pressure applying means 30.

Further, according to a preferred embodiment of the present invention, the recording head 2 and the surface-active agent coating device 4 are integrated, and the surface-active agent is coated and printing is performed while scanning the same along the carriage 20. FIG. 7 shows a schematic diagram of the surfactant coating device 4 integrated with the recording head 2. In this device, the surfactant is contained in a container 61, soaks into a liquid-permeable pad 62 (preferably made of a sponge) and then seeps out onto the surface thereof. As shown in FIG. 8, while the recording head 2 and the coating device 4 are being scanned along the carriage 20, the recording head 2 prints in the region 120 when the recording head 2 and the coating device 4 are in the printing region 13 on the recording medium. Is region 12
1 is coated with a surfactant. During that time, the transfer drum 1 is stopped, but when the recording head 2 and the coating device 4 reach the non-printing area, the transfer drum 1 rotates by a certain angle.
The storage head 2 and the coating device 4 enter the printing area 13 again, and then new printing and application of a surfactant are performed. That is, printing is performed on the area 121 to which the surfactant has been applied, and then the surfactant is applied to a new area. The width L1 applied by the pad 52 is preferably wider than the width L2 of the nozzle group 21 of the recording head 2.

(Ink Composition) The ink composition used in the method of the present invention is not particularly limited as long as it is a so-called water-based ink composition and used in an intermediate transfer type ink jet recording method. Specifically, it is an ink composition containing a colorant, water as a main solvent, a water-soluble organic solvent, and other additives. More specifically, preferred examples of the water-soluble organic solvent include high boiling point low volatility such as glycerin, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, hexylene glycol, polyethylene glycol and polypropylene glycol. And polyhydric alcohols. Further, their monoether compounds, diether compounds and ester compounds such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether and the like can be mentioned. Furthermore, N-methyl-2-pyrrolidone, 1.3-dimethylimidazolidinone, monoethanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, diethanolamine, N-n-butyldiethanolamine, triisopropanol Examples include amine and triethanolamine.

Further, with respect to water as a main solvent, ethanol, propanol,
It is also preferable to add a monohydric alcohol such as isopropanol or butanol.

A pigment or dye can be used as the coloring agent. Examples of the pigment include organic pigments and inorganic pigments. Preferable specific examples of black pigments include carbon blacks such as furnace black, lamp black, acetylene black and channel black (C.I.
I. Pigment Black 7) or copper, iron (C.I.
I. Pigment Black 11), metals such as titanium oxide, and organic pigments such as aniline black (CI Pigment Black 1). Further, preferred specific examples of the color pigment include C.I. I. Pigment Yellow 1 (Fast Yellow G), 3, 12 (Disazo Yellow AAA), 13, 14, 17, 24, 34, 35, 3
7, 42 (yellow iron oxide), 53, 55, 81, 83 (disazo yellow HR), 95, 97, 98, 100, 1
01, 104, 108, 109, 110, 117, 12
0, 138, 153, C.I. I. Pigment Orange 5,
13, 16, 17, 36, 43, 51, C.I. I. Pigment Red 1, 2, 3, 5, 17, 22 (Brilliant First Scarlet), 23, 31, 38, 48:
2 (Permanent Red 2B (Ba)), 48: 2 (Permanent Red 2B (Ca)), 48: 3 (Permanent Red 2B (Sr)), 48: 4 (Permanent Red 2B (Mn)), 49: 1, 52: 2, 53: 1,
57: 1 (Brilliant Carmine 6B), 60: 1, 6
3: 1, 63: 2, 64: 1, 81 (Rhodamine 6G rake), 83, 88, 101 (Bengara), 104, 1
05, 106, 108 (cadmium red), 112,
114, 122 (quinacridone magenta), 123, 1
46, 149, 166, 168, 170, 172, 17
7, 178, 179, 185, 190, 193, 20
9, 219, C.I. I. Pigment Violet 1 (Rhodamine Lake), 3, 5: 1, 16, 19 (Quinacridone Red), 23, 38, C.I. I. Pigment Blue 1, 2, 15 (Phthalocyanine Blue R), 15: 1,
15: 2, 15: 3 (phthalocyanine blue G), 1
5: 4, 15: 6 (phthalocyanine blue E), 16,
17: 127 (dark blue), 28 (cobalt blue), 29
(Ultra-blue), 56, 60, 63, C.I. I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, and the like. In addition to the above, it is possible to use a processed pigment such as graft carbon whose surface is treated with a resin or the like.

The amount of the pigment added is preferably about 0.5 to 15% by weight. The particle size is preferably 25 μm or less,
It is particularly preferably 1 μm or less. In order to uniformly disperse these pigments, a dispersant may be added to the pigment in an amount of 1
˜100% by weight may be added, and the dispersion treatment may be performed with a ball mill or the like.

As the water-soluble dye used in the present ink, a direct dye, an acid dye, a basic dye, an edible dye and the like are used. I. Direct Black 9,1
7, 19, 22, 32, 51, 56, 62, 69, 7
7, 80, 91, 94, 97, 108, 112, 11
3, 114, 117, 118, 121, 122, 12
5, 132, 146, 154, 166, 168, 17
3, 199, C.I. I. Direct Red 2, 4, 9, 2
3, 26, 31, 39, 62, 63, 72, 75, 7
6, 79, 80, 81, 83, 84, 89, 92, 9
5, 111, 173, 184, 207, 211, 21
2, 214, 218, 221, 223, 224, 22
5, 226, 227, 232, 233, 240, 24
1, 242, 243, 247, C.I. I. Direct Violet 7, 9, 47, 48, 51, 66, 90, 9
3, 94, 95, 98, 100, 101, C.I. I. Direct Yellow 8, 9, 11, 12, 27, 28, 2
9, 33, 35, 39, 41, 44, 50, 53, 5
8, 59, 68, 86, 87, 93, 95, 96, 9
8, 100, 106, 108, 109, 110, 13
0, 132, 142, 144, 161, 163, C.I.
I. Direct Blue 1, 10, 15, 22, 25, 5
5, 67, 68, 71, 76, 77, 78, 80, 8
4, 86, 87, 90, 98, 106, 108, 10
9, 151, 156, 158, 159, 160, 16
8, 189, 192, 193, 194, 199, 20
0, 201, 202, 203, 207, 211 213, 214, 218, 225, 229, 236, 2
37, 244, 248, 249, 251, 252, 26
4, 270, 280, 288, 289, 291, C.I.
I. Acid Black 7, 24, 29, 48, 52:
1, 172, C.I. I. Acid Red 35, 42, 5
2, 57, 62, 80, 82, 111, 114, 11
8, 119, 127, 128, 131, 143, 15
1, 154, 158, 249, 254, 257, 26
1, 263, 266, 289, 299, 301, 30
5, 336, 337, 361, 396, 397, C.I.
I. Acid Violet 5, 34, 43, 47, 4
8, 90, 103, 126, C.I. I. Acid Yellow 17, 19, 23, 25, 39, 40, 42, 44, 4
9, 50, 61, 64, 76, 79, 110, 127,
135, 143, 151, 159, 169, 174, 1
90, 195, 196, 197, 199, 218, 21
9, 222, 227, C.I. I. Acid Blue 9,2
5, 40, 41, 62, 72, 76, 78, 80, 8
2, 92, 106, 112, 113, 120, 127:
1, 129, 138, 143, 175, 181, 20
5, 207, 220, 221, 230, 232, 24
7, 258, 260, 264, 271, 277, 27
8, 279, 280, 288, 290, 326, C.I.
I. Basic Black 8, C.I. I. Basic Red 12, 13, 14, 15, 18, 22, 23, 24, 2
5, 27, 29, 35, 36, 38, 39, 45, 4
6, C.I. I. Basic Violet 1, 2, 3, 7,
10, 15, 16, 20, 21, 25, 27, 28, 3
5, 37, 39, 40, 48, C.I. I. Basic Yellow 1, 2, 4, 11, 13, 14, 15, 19, 2
1, 23, 24, 25, 28, 29, 32, 36, 3
9, 40, C.I. I. Basic Blue 1, 3, 5, 7,
9, 22, 26, 41, 45, 46, 47, 54, 5
7, 60, 62, 65, 66, 69, 71, C.I. I. Disperse Yellow 3, 5, 56, 60, 64, 160 C.I. I. Day Super Red 4, 5, 60, 72, 7
3, 91, C.I. I. Desperce Blue 3, 7, 56,
60, 79, 198 C.I. I. Desperse Orange 13, 30, C.I. I. Hood Black, C.I. I. Solvent Black 3, 5, 2
2, C.I. I. Solvent Yellow 19, 44, 98, 10
4, 105, 112, 113, 114 C.I. I. Solvent Red 8, 24, 71, 109, 1
52, 155, 176, 177, 179 C.I. I. Solvent Blue 2, 11, 25, 78, 9
4, 95, C.I. I. Solvent Green 26, C.I. I.
Solvent Orange 5, 40, 45, 72, 63, 6
8, 78 C.I. I. Solvent Violet 13, 31, 32, 3
3, etc. are used.

The amount of these dyes added is generally 0.2 to 10% by weight, more preferably 0.5, based on the total weight of the ink.
Is in the range of up to 5% by weight.

A specific example of the additive is a resin emulsion. The resin emulsion means an emulsion composed of water as a continuous phase and a resin component as a dispersed phase. Examples of the resin component, polyacrylic acid ester, polymethacrylic acid ester, polyethyl acrylic acid ester, styrene-butadiene copolymer, butadiene copolymer, acrylonitrile-butadiene copolymer,
Chloroprene copolymer, crosslinked acrylic resin, crosslinked styrene resin, fluororesin, vinylidene fluoride, benzoguanamine resin, phenol resin, polyolefin resin, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, polystyrene, Styrene-acrylamide copolymer, n-isobutyl acrylate resin, acrylonitrile resin, vinyl acetate resin, acrylamide resin, silicone resin, polyvinyl acetal, rosin resin, polyethylene, polycarbonate,
Vinylidene chloride resin, epoxy resin, vinyl acetate resin,
Examples thereof include ethylene-vinyl acetate copolymer, vinyl acetate-acrylic copolymer, vinyl chloride resin, polyurethane, and the like. It is also possible to use a resin emulsion having a lower molecular weight, for example, polyethylene wax, montan wax, alcohol wax, synthetic oxidation wax, α-olefin-maleic anhydride copolymer, carnauba wax, lanolin, paraffin wax, microcrystalline wax, etc. Is mentioned.

Water-soluble polymers can also be used as additives, and examples thereof include polyalkyl oxides such as polyethylene oxide, polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl butyral, polyacrylic acid, glue, gelatin, casein, albumin, Examples thereof include gum arabic, alginic acid, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl ether, polyvinyl methyl ether, polyethylene glycol, and sugars such as glucose, xylose, sucrose, maltose, arabinose, α-cyclodextrin and starch.

Other examples of additives include water-soluble anionic, cationic, amphoteric or nonionic surfactants. By adding a surfactant, the surface tension of the ink can be lowered and the applicability of the intermediate transfer medium to the elastic layer can be improved from the ink composition side. Specific preferred examples of the anionic surfactant include higher fatty acid salts, higher alkyl dicarboxylic acid salts, higher alcohol sulfuric acid ester salts, higher alkyl sulfonates, alkylbenzene sulfonates, alkylnaphthalene sulfonates,
Naphthalenesulfonic acid salt (Na, K, Li, Ca) formalin polycondensate, condensate of higher fatty acid and amino acid, dialkylsulfosuccinic acid ester salt, alkylsulfosuccinate, naphthenate, etc., alkyl ether carboxylate, acyl Peptide, α-olefin sulfonate, N-acylmethyl taurine, alkyl ether sulfate, secondary higher alcohol ethoxy sulfate, polyoxyethylene alkyl phenyl ether sulfate, monoglycer sulfate, alkyl ether phosphate ester salt,
Examples thereof include alkyl phosphate salt.

Specific examples of preferable cationic surfactants include aliphatic amine salts, quaternary ammonium salts, sulfonium salts and phosphonium salts.

Preferred specific examples of the amphoteric surfactant include carboxybetaine type, aminocarboxylic acid salt, lecithin and the like.

Specific preferred examples of the nonionic surfactant include fluorine-based, silicone-based, acrylic acid copolymer,
Polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene 2
Ethylene oxide derivative of secondary alcohol ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, alkylphenol formalin condensate,
Polyoxyethylene polyoxypropylene block polymer, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene compound fatty acid ester type, polyethylene oxide condensation type polyethylene glycol fatty acid ester, fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid Examples thereof include esters, sucrose fatty acid esters, fatty acid alkanolamides, polyoxyethylene fatty acid amides, polyoxyethylene alkylamine oxides and the like.

The amount of these surfactants added is preferably about 0.05 to 10% by weight, more preferably about 0.1 to 8% by weight, based on the ink.

In the ink composition used in the present invention, if necessary, a pH adjusting agent such as potassium dihydrogen phosphate and disodium hydrogen phosphate, benzoic acid, dichlorophen, hexachlorophen, sorbic acid, p -Hydroxybenzoic acid ester, ethylenediaminetetraacetic acid (E
DTA), sodium dehydroacetate, 1,2-bezothiazolin-3-one, 3,4-isothiazyl-3-one, etc. may be added as an antifungal, antiseptic or antirust agent. Further, urea, thiourea, ethylene urea or the like may be added for the purpose of preventing nozzle drying. Further, addition of a water-soluble resin or a non-water-soluble resin in an emulsion state is also preferable. The ink properties of the ink composition used in the present invention are preferably 50 mPa · sec or less, and particularly preferably 25 mPa · sec or less in order to ensure stable ejection from the head and stable ink supply to the head. preferable.

[0040]

The present invention will be described in more detail with reference to the following examples and reference examples, but the present invention is not limited to these examples and the like. Example A The intermediate transfer type ink jet recording apparatus shown in FIG. 1, which has an elastic layer made of silicone rubber on the surface of the intermediate transfer medium, is coated with various surfactants. Then, the formation of the ink image on the intermediate transfer medium and the transfer efficiency were evaluated. The composition of the used ink composition is as follows. Pigment (carbon black) 1.5% by weight Resin emulsion 15% by weight (styrene-acrylic copolymer emulsion) Diethylene glycol 6% by weight Sugar (glucose) 20% by weight Surfactant (TW-20: manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 3 wt% Other additives and water Surfactants used up to 100% and their HLB values and their evaluation results are shown in the following table. Ink image formation and transfer efficiency were evaluated on the basis of five grades as follows. here,
The evaluation 3 is a preferable limit value from the viewpoint of downsizing and weight reduction of the device.

Ink image formation Line printing and solid printing were carried out, and the formed ink image was evaluated with an index as to whether or not the ink image had a repellency. As a result, it was possible to form an image without repelling the 5: line and solid printing. 4: Image formation was possible without repelling line printing, but some repelling was seen in solid printing. 3: Image formation was possible without repelling line printing, but repelling was observed in about half the area of solid printing. 2: Image formation was possible without repelling line printing, but repelling was observed in more than half of solid printing. 1: Repelling is seen in both line and solid printing, and the ink image is disturbed.

[0042] By The required transfer pressure to cause transfer almost 100% into the recording paper to the ink image on the transfer efficiency transfer medium (linear load), and evaluate the transfer efficiency. As a result, 5: 0.5 kg / cm or less 4: 0.5 or more 1.0 kg / cm or less 3: 1.0 or more 2.5 kg / cm or less 2: 2.5 or more 3.0 kg / cm or less 1: 3 Exceeding 0.0 kg / cm

[0043]

[Table 1]

Reference Example B Surfactants listed in the following table were mixed with rubber forming the elastic layer also listed in the table and vulcanized to obtain the elastic layer of the intermediate transfer drum of the apparatus shown in FIG. . An apparatus using an elastic layer containing no surfactant and an iron oxide-containing silicone rubber produced according to US Pat. No. 5,099,256 was also prepared. Printing was performed using these devices. The ink composition used in the table is as follows.

[0045]   Ink composition 1   Pigment (carbon black) 3% by weight   Resin emulsion 8% by weight   (Styrene-acrylic copolymer emulsion)   Glycerin 8% by weight   Polyvinylpyrrolidone 6% by weight   Surfactant (TW-20, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 1% by weight   Other additives and water up to 100%

[0046]   Ink composition 2   Pigment (carbon black) 3% by weight   Resin emulsion 8% by weight   (Watersol CD-540,     (Manufactured by Dainippon Ink and Chemicals)   Triethanolamine 5% by weight   Triethylene glycol 5% by weight   Other additives and water up to 100%

[0047]

[Table 2]

Ink image formation and transfer efficiency were evaluated as follows. As a result, the next ink image forming line printing was carried out, and the formed ink image was evaluated with an index as to whether or not a repellency was observed in the ink image. As a result, ◯: There was no cissing and the image could be formed. Poor: Repelling is seen and the ink image is disturbed. Transfer Efficiency The transfer efficiency was evaluated by the transfer pressure (line load) required to transfer almost 100% of the ink image on the transfer medium to the recording paper. As a result, ◎: 1 kg / cm or less ○: Exceeding 1.0 2.5 kg / cm or less ×: Exceeding 3.0 kg / cm

[0049]

[Table 3]

[Brief description of drawings]

FIG. 1 is a perspective view of an example of a recording apparatus according to the present invention,
The surfactant 41 is applied to the transfer drum 1 by the wit 42.

2 is a cross-sectional view of the device of FIG. 1 in the X direction.

FIG. 3 is a sectional view of another preferred apparatus according to the present invention, in which a surfactant 41 is applied to the transfer drum 1 by a roller 43.

FIG. 4 is a cross-sectional view of another preferred apparatus according to the present invention in which a solid surfactant 41 is applied to the transfer drum 1.

FIG. 5 is a perspective view of an example of a recording apparatus according to the present invention,
A heater 5 for heating the ink image is provided.

6 is a cross-sectional view of the device of FIG. 5 in the X direction.

FIG. 7 shows an embodiment in which a recording head and a surfactant coating device are integrated.

8 is an explanatory diagram of a recording method using the apparatus of FIG.

FIG. 9 is a diagram when a straight line is formed on a recording medium by a dot group, where (a) is an ideal dot group and (b) is
Is a group of dots where repelling can be seen.

[Explanation of symbols]

1 transfer drum 2 recording head 3 Pressure roller 4 Surfactant coating device 11 Elastic layer 41 Surfactant 42 wick

─────────────────────────────────────────────────── ─── Continuation of front page (31) Priority claim number Japanese Patent Application No. 5-174024 (32) Priority date July 14, 1993 (July 14, 1993) (33) Priority claim country Japan (JP) (72) Inventor Tatsuya Ito 3-5 Yamato 3-chome, Suwa City, Nagano Seiko Epson Corporation (72) Inventor Hiroshi Hirabayashi 3-5 Yamato 3-chome, Suwa City, Nagano Seiko Epson Corporation (56) Reference JP-A-3-197143 (JP, A) JP-A-4-239067 (JP, A) JP-A-2-113986 (JP, A) JP-A-60-171190 (JP, A) JP-A-3-258549 (JP, A) JP-A-3-169634 (JP, A) JP-A-4-168167 (JP, A) JP-A-2-196696 (JP, A) (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/01 B41M 5/00

Claims (9)

(57) [Claims] 1. An intermediate transfer type ink jet recording method, comprising a step of applying a surfactant having an HLB value of 7 to 8 onto an intermediate transfer medium to support the surfactant on the surface of the intermediate transfer medium. A step of ejecting an ink composition onto the intermediate transfer medium to form an ink image, and a step of transferring the ink image on the intermediate transfer medium onto a recording medium at a linear load of 0.5 kg / cm or less. A method comprising :. 2. The method according to claim 1, wherein the surfactant is a silicone-based surfactant. 3. The method according to claim 1, wherein the intermediate transfer medium has an elastic layer made of silicone rubber. 4. The method according to claim 1, further comprising the step of heating the ink image transferred to the recording medium. 5. An intermediate transfer type ink jet recording apparatus, comprising: an intermediate transfer medium having a surfactant having an HLB value of 7 to 8 applied on the surface of the intermediate transfer medium. A recording unit that discharges droplets of the ink composition to form an ink image on the intermediate transfer medium; and a line load of 0.5 kg / cm or less between the ink image on the intermediate transfer medium and the recording medium. And a transfer means for transferring the ink image onto a recording medium by press contacting with the apparatus. 6. The device according to claim 5, wherein the surfactant is a silicone-based surfactant. 7. The method according to claim 5, wherein the intermediate transfer medium has an elastic layer made of silicone rubber. 8. The apparatus according to claim 5, further comprising means for heating the recording medium on which the ink image is transferred. 9. The apparatus according to claim 5, wherein the recording means and the surfactant applying means are integrated.