JP5394055B2 - Non-aqueous inkjet ink - Google Patents

Description

  The present invention relates to a non-aqueous inkjet ink.

In recent years, the inkjet recording method can be easily and inexpensively created images, and thus has been applied to various printing fields such as photographs, various printing, marking, and special printing such as color filters.
Ink jet inks used in such an ink jet recording method include water-based inks mainly containing water, oil-based inks mainly containing non-volatile solvents, non-aqueous inks mainly containing volatile solvents, and room temperature. There are a plurality of inkjet inks, such as a hot melt ink that heats and melts solid ink for printing, and an actinic ray curable ink that is cured by actinic rays such as light after printing.

On the other hand, recording media made of soft polyvinyl chloride are used in a wide range of fields such as outdoor postings that require long-term weather resistance and printed materials that require adhesion to curved objects. There are many methods for printing on soft polyvinyl chloride, but the ink jet recording method is a method suitable for the production of a small variety of products because there is no need to prepare a plate and the time to finish is short.
By the way, in non-aqueous inks, attempts have been made in recent years to use a solvent derived from vegetable oil with a low environmental load. For example, Japanese Patent Application Laid-Open No. 2005-132907 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2007-277352 (Patent Documents 2 to 5) propose non-aqueous inks using a fatty acid ester derived from vegetable oil as a solvent. Yes.
JP-A-2005-132907 JP 2007-277352 A JP 2007-277350 A JP 2007-161892 A JP 2007-161890 A

  However, inks using such vegetable oil-derived fatty acid esters as solvents may have insufficient print quality, and ink reliability may be a problem. In particular, these inks are assumed to be printed on paper, and do not assume a polyvinyl chloride recording medium. For this reason, when printing on a recording medium made of polyvinyl chloride, there is a problem that the print quality (for example, ink ejection, scratching, drying, etc.) is insufficient.

  The present invention has been devised in view of such conventional circumstances, and is sufficient for a recording medium made of polyvinyl chloride in a non-aqueous inkjet ink using a plant-derived fatty acid ester as a main solvent. An object of the present invention is to provide a non-aqueous inkjet ink that has printing quality and has a low environmental impact.

The non-aqueous ink-jet ink according to claim 1 of the present invention is a non-aqueous ink-jet ink comprising at least a solvent, a pigment, and a dispersant, wherein the solvent comprises a plant-derived fatty acid ester, a hydroxy fatty acid. An ester and / or a terpene solvent.
The non-aqueous inkjet ink according to claim 2 of the present invention is the non-aqueous inkjet ink according to claim 1, wherein the content of the plant-derived fatty acid ester and the hydroxy fatty acid ester and / or terpene solvent is 70 with respect to the total composition of the ink. It is characterized by being from wt% to 96 wt%.
The non-aqueous inkjet ink according to claim 3 of the present invention is the non-aqueous ink jet ink according to claim 1, wherein the fatty acid ester is selected from the group consisting of methyl caprylate, methyl caprate, ethylhexyl caprate, methyl laurate and methyl oleate. It is characterized by including at least 1 sort.
The non-aqueous inkjet ink according to claim 4 of the present invention is the non-aqueous inkjet ink according to claim 1, wherein the terpene solvent is selected from the group consisting of limonene, terpineol, terpinyl acetate and isobornyl acetate. It is characterized by including.
The non-aqueous inkjet ink according to claim 5 of the present invention is characterized in that, in claim 1, the hydroxy fatty acid ester contains at least one selected from the group consisting of ethyl lactate, butyl lactate and malate ester. And
The non-aqueous ink-jet ink according to claim 6 of the present invention further includes a vinyl acetate resin, a terpene resin, a polyester resin, a polyamide resin, an acrylic resin, a urethane resin, a cellulose resin, a polylactic acid resin, and a boriacetal. It includes at least one selected from the group consisting of a resin and a polybutyral resin.
The non-aqueous inkjet ink according to claim 7 of the present invention is used for printing on a polyvinyl chloride sheet.

  In the present invention, by using a mixture of a plant-derived fatty acid ester and a hydroxy fatty acid ester and / or a terpene solvent as a solvent, it has sufficient print quality even for a recording medium made of polyvinyl chloride, It is possible to provide a non-aqueous inkjet ink with a low environmental load.

Hereinafter, the inkjet ink according to the present invention will be described.
The non-aqueous inkjet ink of the present invention comprises at least a solvent, a pigment, and a dispersant, and the solvent contains a plant-derived fatty acid ester and a hydroxy fatty acid ester and / or a terpene solvent. It is characterized by.
There are fewer types of plant-derived solvents than petroleum-based solvents, and it is difficult to use from the standpoint of resin solubility. In the present invention, an ink having a performance equivalent to that of a conventional ink is realized by selecting an appropriate combination of solvents.
That is, in the non-aqueous inkjet ink of the present invention, the use of a mixture of a plant-derived fatty acid ester and a hydroxy fatty acid ester and / or a terpene solvent as a solvent is sufficient for a recording medium made of polyvinyl chloride. Print quality and low environmental impact.

The fatty acid ester derived from vegetable oil used in the present invention includes a fatty acid ester obtained by esterifying a fatty acid obtained by hydrolyzing vegetable oil and fat with an alcohol by a known method, and transesterification of the vegetable oil and fat using an appropriate alcohol. Fatty acid esters obtained by (alcolysis) can be mentioned, and any of these fatty acid esters can be used in the present invention as long as it is liquid at room temperature.
Such fatty acid esters preferably include at least one selected from the group consisting of, for example, methyl caprylate, methyl caprate, ethylhexyl caprate, methyl laurate, and methyl oleate.

In the present invention, the terpene solvent used by mixing with the fatty acid ester preferably contains at least one selected from the group consisting of limonene, terpineol, terpinyl acetate and isobornyl acetate.
The hydroxy fatty acid ester preferably contains at least one selected from the group consisting of ethyl lactate, butyl lactate and malate ester, for example.
These terpene solvents and hydroxy fatty acid esters may contain either one or both.

In the non-aqueous inkjet ink of the present invention, the content of the plant-derived fatty acid ester and the hydroxy fatty acid ester and / or terpene solvent is 70% by weight to 96% by weight with respect to the total composition of the ink. preferable. As a result, sufficient print quality can be obtained with less environmental burden.
On the other hand, when the content of the plant-derived fatty acid ester and the hydroxy fatty acid ester and / or the terpene solvent is less than 70% by weight, the environmental load is large and sufficient print quality cannot be obtained. On the other hand, if it exceeds 96%, the print quality becomes insufficient.

  The non-aqueous inkjet ink of the present invention may contain a solvent component other than the fatty acid ester, hydroxy fatty acid ester, and terpene solvent as described above. Such a solvent component is not particularly limited, and a solvent component used in a normal non-aqueous inkjet ink can be used.

The pigment is not particularly limited, and inorganic or organic pigments used in ordinary non-aqueous inkjet inks can be used. Examples of pigments include inorganic pigments such as carbon black, titanium oxide, bitumen, ultramarine, petal, zinc white and calcium carbonate, insoluble azo pigments such as benzidine yellow, hansa yellow and toluidine red, permanent red 2B, pigment scarlet, and ritole. Soluble azo pigments such as red, phthalocyanine blue such as phthalocyanine blue and phthalocyanine green, quinacridone such as quinacridone red, pyranthrone such as pyranslon orange and pyranthrone red, quinophthalone such as quinophthalone yellow, thioindigo, anthraquinone, Examples thereof include organic pigments such as dioxazine, benzimidazolone, isoindolinone, and diketopyrrolopyrrole.
The addition amount of the colorant is preferably 0.5 to 20% by weight based on the whole ink. By setting the addition amount within this range, a desired color density can be obtained, and reliability such as ink ejection stability is good.

  The non-aqueous inkjet ink of the present invention includes a dispersant for dissolving or dispersing the pigment in the ink. As the dispersant, a dispersant usually used in non-aqueous inks using pigments can be used. Such dispersants include hydroxyl group-containing carboxylic acid esters, salts of long-chain polyaminoamides and high molecular weight acid esters, salts of high molecular weight polycarboxylic acids, salts of long chain polyaminoamides and polar acid esters, high molecular weight unsaturated acids. Ester, polymer copolymer, modified polyurethane, modified polyacrylate, polyether ester type anionic activator, naphthalene sulfonic acid formalin condensate salt, aromatic sulfonic acid formalin condensate salt, polyoxyethylene alkyl phosphate ester, Polyoxyethylene nonylphenyl ether, polyester polyamine, stearylamine acetate, etc. can be used.

  Specific examples of these dispersants include Anti-Terra-U (polyaminoamide phosphate), Anti-Terra-203 / 204 (high molecular weight polycarboxylic acid salt), Disperbyk-101 (polyaminoamide phosphate and acid ester). ), 107 (hydroxyl group-containing carboxylic acid ester), 110 (copolymer containing an acid group), 130 (polyamide), 161, 162, 163, 164, 165, 166, 170 (Polymer copolymer), 400, Bykumen (high molecular weight unsaturated acid ester), BYK-P104, P105 (high molecular weight unsaturated acid polycarboxylic acid), P104S, 240S (high molecular weight unsaturated acid polycarboxylic acid) Acid and silicon), Lactimon (long chain amine and unsaturated acid polycarboxylic acid and silicon): The deviation of which are manufactured by BYK Chemie Co., Ltd.) and the like.

Specific examples of the dispersant include Fuka 44, 46, 47, 48, 49, 54, 63, 64, 65, 66, 71, 701, 764, 766 (manufactured by EfkaCHEMICALS), Efka Polymer 100 (modified polyacrylate), 150 (aliphatic modified polymer), 400, 401, 402, 403, 450, 451, 452, 453 (modified) Polyacrylate), 745 (copper phthalocyanine series): all manufactured by EfkaCHEMICALS), florene TG-710 (urethane oligomer), florene DOPA-15B (acrylic oligomer), florene SH-290, the same SP-1000, polyflow no. 50E, No. 300 (acrylic copolymer: all manufactured by Kyoeisha Chemical Co., Ltd.), Disparon KS-860, 873SN, 874 (polymer dispersing agent), # 2150 (aliphatic polycarboxylic acid), # 7004 (poly) Ether ester type), DA-703-50 (polyester acid amide amine salt: all manufactured by Enomoto Kasei Co., Ltd.), and further, demole RN, N (naphthalene sulfonate formalin condensate sodium salt), MS. C, the same SN-B (aromatic sulfonic acid formalin condensate sodium salt), the same EP, homogenol L-18 (polycarboxylic acid type polymer), Emulgen 920, 930, 931, 935, 950, 985 (polyoxyethylene nonylphenyl ether), acetamine 24 (coconut amine acetate), 86 (stearyl amine acetate: all manufactured by Kao Corporation), Solsperse 5000 (phthalocyanine ammonium salt type), 13940 (polyesteramine type), 17000, 18000 (fatty acid amine series), 22000, 24000, 28000 (all manufactured by Avicia), Nikkor T106 (polyoxyethylene sorbitan monooleate), MYS-IEX (polyoxyethylene monostearate), Hex agline4-O (hexaglyceryl tetraoleate: all manufactured by Nikko Chemical Co., Ltd.).

  The non-aqueous inkjet ink of the present invention further includes, as a resin component, for example, vinyl acetate resin, terpene resin, polyester resin, polyamide resin, acrylic resin, urethane resin, cellulose resin, polylactic acid resin, boriacetal resin. And at least one selected from the group consisting of polybutyral resins.

  In addition to the above description, the inkjet ink of the present invention is publicly known depending on the purpose of improving the emission stability, print head and ink cartridge compatibility, storage stability, image storage stability, and other various performances as necessary. Various additives such as a viscosity modifier, a specific resistance modifier, a film forming agent, an ultraviolet absorber, an antioxidant, a discoloration inhibitor, an antifungal agent, and a rust inhibitor can be appropriately selected and used. Any of these various additives is not particularly limited, and additives used in ordinary non-aqueous inkjet inks can be used.

  And the inkjet ink of this invention can be manufactured by disperse | distributing and mixing each component as mentioned above by a suitable method. Preferably, the solid particles and the color pigment are separately separated using an appropriate disperser (eg, ball mill, sand mill, attritor, roll mill, agitator mill, Henschel mixer, colloid mill, ultrasonic homogenizer, jet mill, ang mill, etc.) Then, they are mixed, and then an ink solution is prepared by adding a pH adjuster, an antiseptic, an antifungal agent and the like and sufficiently dissolving them. After sufficiently stirring, the target ink-jet ink can be obtained by performing filtration in order to remove the coarse particle diameter and foreign matters that cause clogging.

  The ink-jet head used when forming an image by discharging the ink-jet ink of the present invention may be an on-demand system or a continuous system. In addition, as a discharge method, an electro-mechanical conversion method (for example, a single cavity type, a double cavity type, a bender type, a piston type, a shear mode type, a shared wall type, etc.), an electro-thermal conversion method (for example, a thermal type) Any ejection method such as an ink jet type or a bubble jet (registered trademark) type may be used.

The ink-jet ink of the present invention can exhibit its effect sufficiently when a recording medium made of polyvinyl chloride is used, and is particularly suitable. However, the ink of the present invention is not limited to this. The present invention is not limited to this, and is applicable to recording media other than polyvinyl chloride, for example, sheets made of resins other than polyvinyl chloride, and various papers.
The non-aqueous ink-jet ink of the present invention has been described above, but the present invention is not limited to this, and can be changed as appropriate without departing from the spirit of the invention.

Specific examples of the present invention will be described below, but the present invention is not limited to these examples.
Example 1
As a pigment, C.I. I. 20 parts by weight of Pigment Black 7, 10 parts by weight of Solspers 2800 as a dispersant, and 70 parts by weight of a solvent were dispersed with a bead mill to obtain a dispersion.
In addition, as said solvent, methyl caprate (made by Lion) as a fatty acid ester and terpinyl acetate (Nippon Fragrance Industries) as a terpene solvent are mixed at a ratio of 1: 1 by weight. Using.
An ink-jet ink was prepared by adding 25 parts by weight of the dispersion, 3 parts by weight of VYHD (vinyl acetate resin: manufactured by Dow Chemical Co., Ltd.), and 72 parts by weight of the mixed solvent, and mixing and dispersing.

(Example 2)
As the solvent, a mosquito-flop phosphoric acid methyl fatty acid ester (manufactured by Lion), and terpineol acetate as terpene solvent is a weight ratio of 1: Except for using the mixture solvent formed by mixing at a ratio of 1, performed An inkjet ink was prepared in the same manner as in Example 1.

(Example 3)
As the solvent, a mosquito-flop phosphoric acid methyl fatty acid ester (manufactured by Lion), and ethyl lactate as a hydroxy fatty acid ester, and terpineol acetate in a weight ratio as terpene solvent 1: 0.5: in a ratio of 0.5 An inkjet ink was prepared in the same manner as in Example 1 except that the mixed solvent was used.

(Comparative example)
An inkjet ink was prepared in the same manner as in Example 1 except that only the fatty acid ester was used as the solvent.
About the inkjet ink of the Example and comparative example prepared as mentioned above, it printed on the vinyl chloride sheet | seat (tarporin) using the piezoelectric inkjet printer.

Using the inkjet inks of the above Examples and Comparative Examples, characteristics such as ejection stability, rubbing property, and drying property in an inkjet printer were evaluated.
As a result, when the inkjet ink of the comparative example was used, characteristics such as non-ejection of the ink and scratching and drying of the obtained image were insufficient.
On the other hand, the ink jet inks of the examples were all capable of printing satisfactorily without any problem, and it was not confirmed that the ink was not ejected or the characteristics such as scratching and drying were deteriorated.

  The present invention is widely applicable to non-aqueous inkjet inks.

Claims (7)

A non-aqueous inkjet ink comprising at least a solvent, a pigment, and a dispersant,
The non-aqueous inkjet ink, wherein the solvent contains a plant-derived fatty acid ester and a hydroxy fatty acid ester and / or a terpene solvent.   2. The non-aqueous system according to claim 1, wherein the content of the plant-derived fatty acid ester and the hydroxy fatty acid ester and / or the terpene solvent is 70% by weight to 96% by weight with respect to the total composition of the ink. Inkjet ink.   2. The non-aqueous inkjet according to claim 1, wherein the fatty acid ester includes at least one selected from the group consisting of methyl caprylate, methyl caprate, ethylhexyl caprate, methyl laurate, and methyl oleate. ink.   The non-aqueous inkjet ink according to claim 1, wherein the terpene solvent includes at least one selected from the group consisting of limonene, terpineol, terpinyl acetate, and isobornyl acetate.   The non-aqueous inkjet ink according to claim 1, wherein the hydroxy fatty acid ester contains at least one selected from the group consisting of ethyl lactate, butyl lactate, and malate.   The non-aqueous ink-jet ink further comprises a vinyl acetate resin, a terpene resin, a polyester resin, a polyamide resin, an acrylic resin, a urethane resin, a cellulose resin, a polylactic acid resin, a boriacetal resin, and a polybutyral resin. The non-aqueous inkjet ink according to claim 1, comprising at least one selected from the group consisting of:   The non-aqueous inkjet ink according to claim 1, which is used for printing on a sheet made of polyvinyl chloride.