Non-aqueous ink composition, recording method using the same, and manufacturing method of recorded matter

Abstract

The present invention provides a non-aqueous ink composition, which has high recording dryness of the non-aqueous ink composition on a substrate surface and good post-processing property of a recorded matter. The non-aqueous ink composition contains an organic solvent, which contains the following organic solvent (a) and the following organic solvent (b). Organic solvent (a): glycol dialkyl ether Organic solvent (b): at least one selected from the group consisting of an alkylamide-based solvent (b1), a cyclic amide-based solvent (b2), and a 6-membered ring or more lactone-based solvent (b3).

Description

Technical Field

[0001] This invention relates to non-aqueous ink compositions, recording methods using the same, and methods for manufacturing recorded materials. Background Technology

[0002] As ink compositions, water-based ink compositions in which colorants are dissolved or dispersed in water or a mixture of water and organic solvents are widely used, as well as non-aqueous ink compositions in which colorants are dissolved or dispersed in anhydrous organic solvents.

[0003] For example, Patent Document 1 describes a non-aqueous ink composition containing a pigment, a specified glycol ether, and a 5-membered ring lactone solvent. Patent Document 1 describes this non-aqueous ink composition as suitable for printing on substrates, exhibiting excellent printing quality, recording stability, recording drying properties, and ink storage stability.

[0004] Furthermore, it is described that the non-aqueous ink composition described in Patent Document 1 preferably includes a binder resin, and that including the binder resin can adjust the viscosity of the non-aqueous ink composition and improve its fixing properties on polyvinyl chloride materials.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: WO2004 / 007626 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] In addition, 5-membered ring lactone solvents are solvents that easily penetrate into resin substrates. Although non-aqueous ink compositions containing 5-membered ring lactone solvents have excellent drying properties, they also have high penetration into resin substrates.

[0010] However, the inventors have realized that if the non-aqueous ink composition permeates into the resin substrate and its permeation amount increases, even if the non-aqueous ink composition on the surface of the resin substrate is thoroughly dried, the solvent in the non-aqueous ink composition will remain on the substrate. Thus, if the solvent in the non-aqueous ink composition remains on the substrate, when the film is laminated onto the recording surface of the recorder, the residual solvent in the substrate may subsequently evaporate, causing the film to lift. It should be noted that in this specification, such a problem is sometimes described as a reduction in the post-processability of the recorder.

[0011] The purpose of this invention is to provide a non-aqueous ink composition that has excellent drying properties and good post-processing properties of the recorded material.

[0012] Furthermore, as a substrate (recording medium) used in non-aqueous ink compositions, a resin substrate having an adhesive layer on one side can be cited as an example. Sometimes, when using such a resin substrate with an adhesive layer on one side, a non-aqueous ink composition is recorded on the side of the resin substrate without the adhesive layer, so that the adhesive layer side adheres to another substrate.

[0013] However, the research of the inventors has clarified that in non-aqueous ink compositions containing 5-membered ring lactone solvents, the 5-membered ring lactone solvents of the non-aqueous ink composition permeate from the decorative layer to the adhesive layer on the back side, resulting in a deterioration of the adhesive properties (adhesion between the recording and the adhered object).

[0014] Furthermore, the research of the inventors has clarified that if a record containing a non-aqueous ink composition is stretched on a resin substrate, the decorative layer of the non-aqueous ink composition will whiten, and the desired decorative layer cannot be formed.

[0015] The object of the present invention is to provide a non-aqueous ink composition that can be used on various substrates. For example, even when using a resin substrate with an adhesive layer on one side and recording (printing) the non-aqueous ink composition on the surface of a substrate without the adhesive layer, the degradation of the adhesiveness of the adhesive layer (the adhesion between the recording and the adhered object) can be suppressed, and the whitening of the decorative layer can be effectively suppressed even when the recording is stretched.

[0016] Methods for solving problems

[0017] In order to solve the above-mentioned problems, the inventors conducted in-depth research and found that the above-mentioned problems could be solved by using a non-aqueous ink composition containing a specified organic solvent, thus completing the present invention.

[0018] Furthermore, the inventors conducted in-depth research to solve the aforementioned problems and discovered that a non-aqueous ink composition containing a specified organic solvent and a resin having a specified weight-average absolute molecular weight can solve the above problems, thus completing the present invention. Specifically, the present invention provides the following solution.

[0019] (1) A non-aqueous ink composition containing an organic solvent, wherein the organic solvent contains the following organic solvent (a) and the following organic solvent (b).

[0020] Organic solvent (a): Diol dialkyl ether

[0021] Organic solvent (b): at least one selected from alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with more than 6 members (b3).

[0022] (2) The non-aqueous ink composition according to (1), wherein the content of the organic solvent (b) is in the range of 3.0% by mass or more and 30.0% by mass or less in the total amount of the non-aqueous ink composition.

[0023] (3) The non-aqueous ink composition according to (1) or (2), wherein the organic solvent (a) is a dialkyl glycol ether of formula (1).

[0024]

Chemical Formula 1

[0025]

[0026] (In formula (1), R1 and R3 are alkyl groups, and R2 represents ethylene or propylene. n represents an integer from 2 to 4.)

[0027] (4) The non-aqueous ink composition according to (3), wherein the total number of carbon atoms contained in R1 and R3 in the above formula (1) is 2 or more and 6 or less.

[0028] (5) The non-aqueous ink composition according to (4), wherein in the organic solvent (a), R1 in the above formula (1) is methyl or ethyl, R3 in the above formula (1) is ethyl, and / or R1 and R3 in the above formula (1) are methyl and R2 is propylene.

[0029] (6) The non-aqueous ink composition according to any one of (1) to (5), wherein the content of the organic solvent (a) and impurities is 0.5% by mass or less in the total amount of organic solvent (a), and the content of impurities from the organic solvent (b) is 0.5% by mass or less in the total amount of organic solvent (b).

[0030] (7) A non-aqueous ink composition comprising an organic solvent and a resin, wherein the organic solvent comprises an organic solvent (b) thereof, and the resin has a weight-average absolute molecular weight of 15,000 or more and 80,000 or less.

[0031] Organic solvent (b): at least one selected from alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with more than 6 members (b3).

[0032] (8) The non-aqueous ink composition according to (7), wherein the resin comprises at least one selected from acrylic resins, vinyl chloride-vinyl acetate copolymer resins and cellulose resins.

[0033] (9) The non-aqueous ink composition according to any one of (7) or (8), wherein the content of impurities from the organic solvent (b) is less than 0.5% by mass in the total amount of organic solvent (b).

[0034] (10) The non-aqueous ink composition according to any one of (1) to (9), wherein the organic solvent (b) is an alkylamide solvent (b1).

[0035] (11) The non-aqueous ink composition according to (10), wherein the alkylamide solvent (b1) is represented by the following general formula (2).

[0036]

Chemical Formula 2

[0037]

[0038] (In formula (2), R4 is hydrogen or an alkyl group with 1 or more but less than 4 carbon atoms, and R5 represents an alkyl group with 2 or more but less than 4 carbon atoms.)

[0039] (12) The non-aqueous ink composition according to (11), wherein the alkylamide solvent (b1) contains at least one selected from N,N-diethylformamide, N,N-diethylpropionamide and N,N-diethylacetamide.

[0040] (13) The non-aqueous ink composition according to any one of (1) to (9), wherein the organic solvent (b) is a cyclic amide solvent (b2).

[0041] (14) The non-aqueous ink composition according to (13), wherein the cyclic amide solvent (b2) is represented by the following general formula (3).

[0042]

Chemical Formula 3

[0043]

[0044] (In formula (3), R6 is an alkylene group with 4 or more but less than 5 carbon atoms, and R7 represents hydrogen or an alkyl or unsaturated hydrocarbon group with 1 or more but less than 2 carbon atoms.)

[0045] (15) The non-aqueous ink composition according to (14), wherein the cyclic amide solvent (b2) contains at least one selected from ε-caprolactam, N-methylcaprolactam and N-vinylcaprolactam.

[0046] (16) The non-aqueous ink composition according to any one of (1) to (9), wherein the organic solvent (b) is a lactone solvent (b3) with a 6-membered ring or more.

[0047] (17) The non-aqueous ink composition according to (16), wherein the lactone solvent (b3) with a 6-membered ring or more is represented by the following general formula (4).

[0048] [Chemical Formula 4]

[0049]

[0050] (In formula (4), R8 is an alkylene group with 4 or more but less than 5 carbon atoms, and R9 represents hydrogen or an alkyl group with 1 or more but less than 2 carbon atoms.)

[0051] (18) The non-aqueous ink composition according to (17), wherein the lactone solvent (b3) with a 6-membered ring or more contains at least one selected from δ-valerolactone, δ-caprolactone and ε-caprolactone.

[0052] (19) The non-aqueous ink composition according to any one of (1) to (18), wherein the water content is 1.0% by mass or less in the total amount of the non-aqueous ink composition.

[0053] (20) The non-aqueous ink composition according to any one of (1) to (19) is used on a resin substrate.

[0054] (21) A recording method wherein the non-aqueous ink composition of any one of (1) to (19) is sprayed onto the surface of a substrate by inkjet printing.

[0055] (22) A method for manufacturing a record, wherein the non-aqueous ink composition of any one of (1) to (19) is sprayed onto the surface of a substrate by inkjet printing.

[0056] Invention Effects

[0057] The non-aqueous ink composition of the present invention exhibits excellent recording and drying properties and good post-processing properties of the recorded material. Therefore, the non-aqueous ink composition of the present invention can be used on various substrates (recording media), including non-absorbent substrates such as resin substrates and metal plates and glass, absorbent substrates such as paper and cloth, and substrates with surface coatings.

[0058] Furthermore, the non-aqueous ink composition of the present invention can be used on various substrates (recording media), including non-absorbent substrates such as resin substrates and metal plates and glass, absorbent substrates such as paper and cloth, and substrates with surface coatings. For example, even when using a resin substrate with an adhesive layer on one side, and recording (printing) the non-aqueous ink composition of the present invention on the surface of a substrate without the adhesive layer, the degradation of the adhesiveness of the adhesive layer (the adhesion between the recording and the adhered object) can be suppressed, and the whitening of the decorative layer can be effectively suppressed even when the recording is stretched. Detailed Implementation

[0059] The following describes specific embodiments of the present invention in detail. However, the present invention is not limited to any of the following embodiments and can be implemented with appropriate modifications within the scope of the purpose of the present invention.

[0060] <The non-aqueous ink composition of the first embodiment>

[0061] The non-aqueous ink composition of this embodiment contains an organic solvent, characterized in that, as an organic solvent, it contains a dialkyl glycol ether (organic solvent (a)) and at least one of the following (organic solvent (b)): an alkyl amide solvent (b1), a cyclic amide solvent (b2), and a lactone solvent with a 6 or more members (b3).

[0062] If such a non-aqueous ink composition is used, it exhibits excellent drying properties and good post-processing properties of the recorded material. Therefore, the non-aqueous ink composition of this embodiment can be used on various substrates (recording media), including resin-based substrates.

[0063] Here, "non-aqueous ink composition" refers to an ink composition (oil-based ink composition) that intentionally contains organic solvents but no water, except for moisture in the atmosphere and water inevitably present from additives, etc., and is different from an aqueous ink composition in which colorants are dissolved or dispersed in water or a mixture of water and organic solvents. By being a "non-aqueous ink composition," it exhibits high quick-drying properties and is easy to print (record) on non-absorbent substrates such as resin substrates and metal substrates. It should be noted that the same applies to the non-aqueous ink composition of the second embodiment described later.

[0064] The moisture content in the total amount of the non-aqueous ink composition is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, even more preferably 1.0% by mass or less, and even more preferably 0.5% by mass or less. For example, when the non-aqueous ink composition is a non-aqueous inkjet ink composition that is sprayed onto the surface of a substrate by inkjet printing, problems such as clogging of the ink composition in the nozzle disappear, and the spraying stability and storage stability can be improved.

[0065] The components contained in the non-aqueous ink composition of this embodiment will be described below.

[0066] [Organic solvents]

[0067] Organic solvents include organic solvent (a) and organic solvent (b).

[0068] Organic solvent (a): Diol dialkyl ether

[0069] Organic solvent (b): at least one selected from alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with more than 6 members (b3).

[0070] The organic solvent (a) and organic solvent (b) will be described in more detail below.

[0071] (Organic solvent(a))

[0072] The organic solvent (a) is a glycol dialkyl ether. Glycol dialkyl ethers are compounds in which the OH groups at both ends of a glycol are replaced by alkyl groups. Because glycol dialkyl ethers have moderate volatility, the non-aqueous ink composition dries before the image bleeds, resulting in good image quality. Furthermore, glycol dialkyl ethers have low resin permeability, thus improving the post-processing properties of the recorded material. In addition, glycol dialkyl ethers exhibit low solubility and swelling in plastic components and adhesives; therefore, when the non-aqueous ink composition is a non-aqueous inkjet ink composition that is sprayed onto the surface of a substrate by inkjet printing, it also has good compatibility with components such as inkjet heads.

[0073] Diol dialkyl ethers, for example, can be represented by the diol dialkyl ether shown in the following formula (1).

[0074] [Chemical Formula 5]

[0075]

[0076] (In formula (1), R1 and R3 are alkyl groups, and R2 represents ethylene or propylene. n represents an integer from 2 to 4.)

[0077] Specifically, examples of dialkyl glycol ethers include ethylene glycol dibutyl ether, ethylene glycol dipropyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dipropyl ether, diethylene glycol methyl propyl ether, diethylene glycol methyl isopropyl ether, diethylene glycol dibutyl ether, diethylene glycol methyl butyl ether, diethylene glycol ethyl butyl ether, diethylene glycol methyl-2-ethylhexyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, and triethylene glycol methyl ethyl ether. Tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol methyl ethyl ether, propylene glycol diethyl ether, propylene glycol methyl ethyl ether, propylene glycol methyl propyl ether, propylene glycol methyl butyl ether, propylene glycol methyl-2-ethylhexyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol methyl ethyl ether, dipropylene glycol methyl propyl ether, dipropylene glycol dipropyl ether, dipropylene glycol methyl butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, tripropylene glycol methyl ethyl ether, etc.

[0078] Among the dialkyl glycol ethers, the preferred dialkyl glycol ethers are those in formula (1) where the total number of carbon atoms in R1 and R3 is 2 or more and 8 or less, more preferably dialkyl glycol ethers with 2 or more and 6 or less, and even more preferably dialkyl glycol ethers in formula (1) where R1 is methyl or ethyl and R3 is ethyl, and / or dialkyl glycol ethers in formula (1) where R1 and R3 are methyl and R2 is propylene.

[0079] Dialkyl glycol ethers, in which the total number of carbon atoms in R1 and R3 is 2 or more and 6 or less, are more volatile than, for example, diethylene glycol dibutyl ether (in which the total number of carbon atoms in R1 and R3 is 8), and therefore become non-aqueous ink compositions with excellent recording and drying properties.

[0080] Examples of dialkyl glycol ethers in which the total number of carbon atoms in R1 and R3 is 2 or more and 6 or less include diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, diethylene glycol methyl isopropyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, and tetraethylene glycol diethyl ether.

[0081] Furthermore, dialkyl glycol ethers in formula (1) where R1 is methyl or ethyl and R3 is ethyl, and / or dialkyl glycol ethers in formula (1) where R1 and R3 are methyl and R2 is propylene, have lower permeability compared to, for example, diethylene glycol dimethyl ether (where R1 and R3 are methyl and R2 is ethylene). Therefore, the post-processing properties of the recorded material can be further improved more effectively.

[0082] Examples of dialkyl glycol ethers in formula (1) where R1 is methyl or ethyl and R3 is ethyl include diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, triethylene glycol diethyl ether, tetraethylene glycol diethyl ether, etc. Examples of dialkyl glycol ethers in formula (1) where R1 and R3 are methyl and R2 is propylene glycol include dipropylene glycol dimethyl ether.

[0083] There is no particular limitation on the lower limit of the content of organic solvent (a), but it is preferred to contain 30.0% by mass or more in the total amount of non-aqueous ink composition, more preferably 40.0% by mass or more, and even more preferably 50.0% by mass or more.

[0084] There is no particular limit to the upper limit of the content of organic solvent (a), but it is preferred to contain 90.0% by mass or less, and more preferably 80.0% by mass or less, in the total amount of the non-aqueous ink composition.

[0085] It should be noted that glycol dialkyl ethers sometimes absorb substances such as water vapor present in the atmosphere; therefore, it is preferable to pre-dry the glycol dialkyl ethers before mixing them with other components. By using pre-dried glycol dialkyl ethers, the moisture content in the non-aqueous ink composition can be adjusted to an appropriate amount (e.g., less than 1.0% by mass in the total amount of the non-aqueous ink composition). Methods for drying glycol dialkyl ethers include, for example, blowing a dry, inert gas (e.g., nitrogen) into an atmosphere of inert gas such as nitrogen for a specified time.

[0086] Furthermore, organic solvent (a) (dialkyl glycol ether) is prone to producing impurities such as polymers, by-reactants, and decomposition products during the manufacturing process. For example, the impurity content in commercially available dialkyl glycol ethers sometimes reaches about 10% by mass in the total amount of dialkyl glycol ether. Therefore, it is preferable to pre-set the content of impurities from organic solvent (a) to be less than 0.5% by mass in the total amount of organic solvent (a) before mixing with other components. Sometimes, low-boiling-point impurities contained in organic solvent (a) can degrade the post-processing properties of the recorded material, or cause adverse effects such as dissolution and swelling of plastics and adhesives used in printer components such as inkjet heads. In addition, if the impurities contained in the dialkyl glycol ether are high-boiling-point, the reduced drying properties of the non-aqueous ink composition can sometimes cause ink bleeding. By pre-setting the organic solvent (a) to have an impurity content of less than 0.5% by mass in the total organic solvent (a) before mixing with other components, the drying properties, component adaptability, and post-processing properties of the recorded material are improved.

[0087] Impurities contained in organic solvent (a) include triethylene glycol (boiling point 285°C), tetraethylene glycol (boiling point 327°C), polyethylene glycol (boiling point above 330°C), ethylene glycol monoethyl ether (boiling point 135°C), ethylene glycol monomethyl ether (boiling point 124°C), ethylene glycol diethyl ether (boiling point 121°C), ethylene glycol dimethyl ether (boiling point 98°C), diethyl ether (boiling point 35°C), methyl ethyl ether (boiling point 12°C), diethyl ketone (boiling point 101°C), dimethyl ketone (boiling point 57°C), methyl ethyl ketone (boiling point 80°C), ethoxyethanol (boiling point 135°C), and ethanol (boiling point 78°C), but are not limited to these.

[0088] As a method for purifying organic solvent (a), it can be achieved by repeatedly distilling the organic solvent (a), reducing the temperature step of distillation to minimize the presence of impurities, or repeatedly extracting. In addition, in industrial manufacturing processes, besides the above-mentioned processes, it can also be achieved by implementing pollution suppression measures.

[0089] (Organic solvent(b))

[0090] The organic solvent (b) is at least one selected from alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3). Compared to non-aqueous ink compositions containing five-membered ring lactone solvents, this organic solvent (b) exhibits lower permeability to the substrate. Therefore, it becomes a non-aqueous ink composition with good post-processing properties for recorded materials.

[0091] Furthermore, this organic solvent (b) is a solvent that penetrates the substrate to a certain extent, resulting in faster drying on the substrate surface. Therefore, ink compositions containing organic solvent (b) exhibit similarly high drying properties as non-aqueous ink compositions containing 5-membered ring lactone solvents, and exhibit less ink bleeding during printing (recording), resulting in clear printing. Such an effect of less ink bleeding cannot be achieved simply by selecting a solvent with a low boiling point to improve drying performance.

[0092] Furthermore, the organic solvent (b) exhibits less solubility and swelling in plastic components and adhesives. Therefore, when the non-aqueous ink composition is a non-aqueous inkjet ink composition that is sprayed onto the surface of a substrate by inkjet printing, it also has good compatibility with components such as inkjet heads.

[0093] The following sections will describe the alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3) contained in the organic solvents (b).

[0094] (1) Alkylamide solvents

[0095] Alkylamide solvents refer to solvents containing alkyl (C) groups. n H 2n+1 Compounds containing -C(=O)-N- groups (amide bonds) are solvents containing compounds consisting of hydrogen or alkyl groups and -C(=O)-N- groups. Alkylamide solvents, for example, solvents having the following structures are preferred.

[0096]

Chemical Formula 6

[0097]

[0098] (In formula (2), R4 is hydrogen or an alkyl group with 1 or more but less than 4 carbon atoms, and R5 represents an alkyl group with 2 or more but less than 4 carbon atoms.)

[0099] Examples of alkylamide solvents include N,N-diethylformamide, N,N-diethylacetamide, N,N-dipropylformamide, N,N-dibutylformamide, N,N-diethylpropionamide, and N,N-dipropylpropionamide. From the viewpoint of particularly maximizing the effects of the present invention, it is preferable to contain at least one selected from N,N-diethylformamide, N,N-diethylpropionamide, and N,N-diethylacetamide.

[0100] It should be noted that it may contain N,N-dimethylformamide and N,N-dimethylacetamide, but from the viewpoint of particularly maximizing the effects of the present invention, it is preferable not to contain N,N-dimethylformamide and N,N-dimethylacetamide.

[0101] (2) Cyclic amide solvents

[0102] Cyclic amide solvents are solvents having a cyclic structure and containing a -C(=O)-N- group in that cyclic structure. For example, solvents having the following structure are preferred as cyclic amide solvents.

[0103] [Chemical Formula 7]

[0104]

[0105] (In formula (3), R6 is an alkylene group with 4 or more but less than 5 carbon atoms, and R7 represents hydrogen or an alkyl or unsaturated hydrocarbon group with 1 or more but less than 2 carbon atoms.)

[0106] It should be noted that R7 is more preferably an alkyl group having 1 or more but less than 2 carbon atoms.

[0107] Examples of cyclic amide solvents include N-methylcaprolactam, N-acetylcaprolactam, ε-caprolactam, N-vinylcaprolactam, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-propyl-2-pyrrolidone, N-ethyl-ε-caprolactam, N-propyl-ε-caprolactam, and N-methyl-ε-caprolactam. Preferably, the solvent contains at least one selected from ε-caprolactam, N-methylcaprolactam, and N-vinylcaprolactam.

[0108] It should be noted that the product may contain N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolinone, or N-methyloxazolidinone, but from the viewpoint of particularly maximizing the effects of the present invention, it is preferable that it does not contain N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolinone, or N-methyloxazolidinone.

[0109] (3) Lactone solvents with 6 or more members

[0110] Lactone solvents with 6 or more members refer to solvents having a cyclic ester structure with 6 or more members. For example, solvents with the following structures are preferred among lactone solvents with 6 or more members.

[0111] [Chemical Formula 8]

[0112]

[0113] (In formula (4), R8 is an alkylene group with 4 or more but less than 5 carbon atoms, and R9 represents hydrogen or an alkyl group with 1 or more but less than 2 carbon atoms.)

[0114] Examples of lactone solvents with 6 or more membered rings include δ-pentanolide, δ-caprolactone, δ-heptanolide, δ-octanolide, δ-nonanolide, δ-decanolide, δ-undecaprolactone, and ε-caprolactone.

[0115] If the ink composition contains the above-mentioned organic solvent (a) and organic solvent (b), it becomes a non-aqueous ink composition that exhibits the effects of the present invention, wherein the organic solvent (b) contains at least one selected from alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3). Preferably, the organic solvent (b) contains at least one of alkyl amide solvents (b1) and cyclic amide solvents (b2), and particularly preferably contains alkyl amide solvent (b1).

[0116] There is no particular limit to the upper limit of the content of organic solvent (b) (selected from at least one of alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with more than 6 members (b3)). It is preferred to contain 60.0% by mass or less in the total amount of non-aqueous ink composition, more preferably 45.0% by mass or less, even more preferably 35.0% by mass or less, and even more preferably 17.0% by mass or less.

[0117] There is no particular limitation on the lower limit of the content of organic solvent (b), but it is preferred to contain 3.0% by mass or more in the total amount of ink composition, and more preferably 5.0% by mass or more.

[0118] It should be noted that the upper and lower limits of the content of the aforementioned organic solvent (b) are common to all alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with 6 or more members (b3). In particular, when the organic solvent (b) is a lactone solvent with 6 or more members (b3), it is most preferably contained at a content of 5.0% by mass or more and 15.0% by mass or less in the total amount of the non-aqueous ink composition.

[0119] Preferably, before mixing the organic solvent (b) (selected from at least one of alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3)) with other components, the content of impurities from the organic solvent (b) is set to be 0.5% by mass or less in the total amount of the organic solvent (b). Due to the low-boiling-point impurities contained in the organic solvent (b), the post-processing properties of the recorded material may deteriorate, and adverse conditions such as dissolution and swelling of plastics and adhesives used in printer components such as inkjet heads may occur. By setting the content of impurities from the organic solvent (b) to be 0.5% by mass or less in the total amount of the organic solvent (b) before mixing with other components, the drying properties of the recording material, component compatibility, and post-processing properties of the recorded material are improved. In addition, the ink bleeding caused by the reduction in drying properties due to high-boiling-point impurities contained in the organic solvent (b) can be more effectively suppressed.

[0120] As a method for purifying organic solvent (b), it can be achieved by repeatedly distilling the organic solvent (b), reducing the temperature step of distillation to minimize the presence of impurities, or repeatedly extracting. In addition, in industrial manufacturing processes, besides the above-mentioned processes, it can also be achieved by implementing pollution suppression measures.

[0121] (Other organic solvents)

[0122] The organic solvent may contain organic solvents other than those mentioned in organic solvents (a) and organic solvents (b). Specifically, examples include diol monoalkyl ethers and carbonates, where one OH group of the diol is replaced by an alkyl group.

[0123] Examples of glycol monoalkyl ethers include ethylene glycol mono-n-butyl ether, ethylene glycol mono-isobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol mono-2-ethylhexyl ether, diethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, triethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, tetraethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, and tetraethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, ... 2-Ethylhexyl ether, propylene glycol mono-n-butyl ether, propylene glycol mono-isobutyl ether, propylene glycol mono-tert-butyl ether, propylene glycol mono-2-ethylhexyl ether, dipropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, tripropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl) ether, tetrapropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, etc.

[0124] Examples of carbonates include ethylene carbonate and propylene carbonate.

[0125] In addition, it may contain organic solvents other than those mentioned above. Specifically, examples include cyclic esters such as γ-butyrolactone, γ-valactone, γ-caprolactone, γ-heptanolactone, γ-octanolactone, γ-nonanolactone, γ-decanolactone, and γ-undecanolactone; oxazolidinone solvents such as 3-methyl-2-oxazolidinone, 3-ethyl-2-oxazolidinone, and N-vinylmethyloxazolidinone; acetate solvents such as triethylene glycol butyl ether acetate, ethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol methyl ether acetate, diethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, 1-methoxy-2-propyl acetate, 2-methylbutyl acetate, 3-methoxybutyl ether acetate, and cyclohexyl acetate; 3-methyl Amide solvents that differ from alkylamide solvents (b1) and cyclic amide solvents (b2), such as oxypropionamide, 3-butoxypropionamide, N,N-dimethyl-3-methoxypropionamide, N,N-dibutyl-3-methoxypropionamide, N,N-dibutyl-3-butoxypropionamide, and N,N-dimethyl-3-butoxypropionamide; alkyl alcohols with 1 to 5 carbon atoms, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, isobutanol, and n-pentanol; monohydric alcohol solvents such as 3-methoxy-3-methyl-1-butanol, 3-methoxy-1-propanol, 1-methoxy-2-propanol, and 3-methoxy-n-butanol; acetone, diacetone alcohol, methyl ethyl ketone, and methyl n-butanol. Ketones or ketone alcohols such as propyl ketone, methyl isopropyl ketone, methyl n-butyl ketone, methyl isobutyl ketone, methyl n-pentyl ketone, methyl hexyl ketone, methyl isopentyl ketone, diethyl ketone, ethyl n-propyl ketone, ethyl isopropyl ketone, ethyl n-butyl ketone, ethyl isobutyl ketone, di-n-propyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methyl cyclohexanone, isophorone, and acetyl ketone; ethers such as tetrahydrofuran and dioxane; copolymers of polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-propanediol, isobutylene glycol, triethylene glycol, tripropylene glycol, tetraethylene glycol, 1,3-propanediol, 2-methyl-1,2-propanediol, and 2-methyl-1,2-propanediol. Diols such as alcohols, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, and 2-methyl-2,4-pentanediol; triols such as glycerol, trimethylolethane, trimethylolpropane, and 1,2,6-hexanetriol; tetraols such as mesoerythritol and pentaerythritol; monoethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, N-ethylethanolamine, N-butylethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, and N-butyldiethanolamine; and alkanolamines such as ethanolamines.Acetic acid esters such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, hexyl acetate, and octyl acetate; lactic acid esters such as methyl lactate, ethyl lactate, butyl lactate, propyl lactate, ethylhexyl lactate, pentyl lactate, and isoamyl lactate; saturated hydrocarbons such as n-hexane, isohexane, n-nonane, isononane, dodecane, and isododecane; unsaturated hydrocarbons such as 1-hexene, 1-heptene, and 1-octene; cyclohexene, cyclohexene, and cyclohexene. Resins include cyclic unsaturated hydrocarbons such as hepten, cyclooctene, 1,3,5,7-cyclooctatetraene, and cyclododecene; aromatic hydrocarbons such as benzene, toluene, and xylene; morpholine solvents such as N-methylmorpholine, N-ethylmorpholine, and N-formylmorpholine; terpene solvents; and dimethyl oxalate, diethyl oxalate, dimethyl malonate, diethyl malonate, dimethyl succinate, diethyl succinate, dimethyl glutarate, and diethyl glutarate. Solvents with appropriate HLB values ​​are preferably selected based on the combined resins and dispersants.

[0126] Additionally, the ink composition may contain a 5-membered ring lactone solvent, but it is preferable that it does not contain a 5-membered ring lactone solvent. When a 5-membered ring lactone solvent is present, its content in the total amount of the non-aqueous ink composition is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, even more preferably 1.0% by mass or less, and even more preferably not present.

[0127] Examples of 5-membered ring lactone solvents include γ-butyrolactone, γ-valerolactone, γ-caprolactone, and γ-heptylactone.

[0128] [Colorant]

[0129] The colorant contained in the non-aqueous ink composition of this embodiment is not particularly limited and can be either dye-based or pigment-based. From the viewpoint of good water resistance, lightfastness, and other resistance of the recorded material, pigments (pigment-based colorants) are preferred. In the non-aqueous ink composition of this embodiment, the pigments that can be used are not particularly limited, and examples include organic or inorganic pigments used in conventional ink compositions. One type can be used alone, or two or more types can be used in combination.

[0130] Specific examples of organic pigments include insoluble azo pigments, soluble azo pigments, derivatives of dyes, phthalocyanine-based organic pigments, quinacridone-based organic pigments, perylene-based organic pigments, violet-based organic pigments, azomethyl alkaloid-based organic pigments, anthraquinone-based organic pigments (anthrone-based organic pigments), xanthones-based organic pigments, diketopyrrolopyrrole-based organic pigments, dioxazine-based organic pigments, nickel azo pigments, isoindolineone-based organic pigments, pinanthrone-based organic pigments, thioindole-based organic pigments, condensed azo pigments, benzimidazolone-based organic pigments, quinacridone-based organic pigments, isoindoline-based organic pigments, quinacridone-based solid solution pigments, and perylene-based solid solution pigments. Other examples of pigments include lake pigments and carbon black.

[0131] If organic pigments are exemplified by their color index (CI) numbers, then examples of CI pigments include: Yellow 1, 2, 3, 12, 13, 14, 16, 17, 20, 24, 73, 74, 75, 83, 93, 95, 97, 98, 109, 110, 114, 117, 120, 125, 128, 129, 130, 137, 138, 139, 147, 148, 150, 151, 153, 154, 155, 166, 168, 180, 185, 213, 214; CI pigments include Red 5, 7, 9, 12, 48, 49, 52, 53, 57, 1, 97, 112, 122, 123, 146, 149, 150, 1 68, 177, 180, 184, 192, 202, 206, 208, 209, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240, 254, 255, 269, 291, CI Pigment Orange 16, 36, 43, 51, 55, 59, 61, 64, 71, 73, CI Pigment Purple 19, 23, 29, 30, 37, 40, 50, CI Pigment Blue 15, 15:1, 15:3, 15:4, 15:6, 16, 22, 60, 64, CI Pigment Green 7, 36, 58, 59, 62, 63, CI Pigment Brown 23, 25, 26, CI Pigment Black 7, etc.

[0132] In the non-aqueous ink composition of this embodiment, specific examples of dyes that can be used include azo dyes, benzoquinone dyes, naphthoquinone dyes, anthraquinone dyes, cyanine dyes, squaric acid cyanine dyes, ketone acid dyes, cyanine dyes, ursine dyes, diarylmethane dyes, triarylmethane dyes, fluorane dyes, spiropyran dyes, phthalocyanine dyes, indigo dyes such as indigo, arginine anhydride dyes, nickel complex dyes, and chamomile ring dyes.

[0133] In the non-aqueous ink composition of this embodiment, specific examples of inorganic pigments that can be used include titanium dioxide, barium sulfate, calcium carbonate, zinc oxide, barium carbonate, silicon dioxide, talc, clay, synthetic mica, aluminum oxide, zinc white, lead sulfate, chrome yellow, zinc yellow, ferric oxide (red iron oxide (III)), cadmium red, ultramarine, Prussian blue, chromium oxide green, cobalt green, amber, titanium black, aluminum, titanium, indium, synthetic iron black, and inorganic solid solution pigments.

[0134] In the non-aqueous ink composition of this embodiment, the average dispersed particle size of the pigments that can be contained is not particularly limited as long as the desired color development can be achieved. Although it varies depending on the type of pigment used, from the viewpoint of good pigment dispersibility and dispersion stability and sufficient tinting strength, the volume average particle size is preferably in the range of 5 nm or more, more preferably 20 nm or more, and even more preferably 30 nm or more. By making the volume average particle size at or above the above-mentioned lower limit value, the lightfastness of the non-aqueous ink composition can be improved. The volume average particle size is preferably in the range of 300 nm or less, more preferably 200 nm or less, and even more preferably 150 nm or less. By making the volume average particle size at or below the above-mentioned upper limit value, in the case where the non-aqueous ink composition is a non-aqueous inkjet ink composition that is sprayed onto the surface of a substrate by inkjet printing, the inkjet printing stability can be improved. It should be noted that, in this embodiment, the volume average particle size of the pigment is the volume average particle size (D50) measured using a particle size distribution measuring device (NANOTRACWAVE particle size analyzer manufactured by MicrotracBEL Co., Ltd.) at 25°C.

[0135] Furthermore, in the case of an ink group comprising a non-aqueous ink composition of this embodiment, the volume average particle size of the pigments contained in each non-aqueous ink composition may be the same or different.

[0136] In the non-aqueous ink composition of this embodiment, the pigment content is not particularly limited and can be adjusted appropriately as long as the desired image can be formed. Specifically, although it varies depending on the type of pigment, it is preferably 0.05% by mass or more, more preferably 0.1% by mass or more in the total amount of the non-aqueous ink composition. It is preferably 20% by mass or less in the total amount of the non-aqueous ink composition, more preferably 10% by mass or less. By keeping the pigment content within the range of 0.05% by mass or more, or 20% by mass or less, an excellent balance between pigment dispersion stability and tinting strength can be achieved.

[0137] Furthermore, there are no particular limitations on the colors that can be recorded (printed) using the non-water-based ink composition of this embodiment. Pigments can be selected and combined according to the purpose. Colors can also be used for various colors of ink such as yellow, magenta, cyan, black, light magenta, light cyan, light black, orange, green, red, white, etc.

[0138] [Resin]

[0139] To improve the fixing properties, water resistance, and tensile strength of the decorative layer formed from the non-aqueous ink composition, the non-aqueous ink composition of this embodiment may contain a resin. The resin is not particularly limited, and examples include acrylic resins, polystyrene resins, polyester resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, polyethylene resins, polyurethane resins, rosin-modified resins, phenolic resins, terpene resins, polyamide resins, vinyltoluene-α-methylstyrene copolymers, ethylene-vinyl acetate copolymers, cellulose acetate butyrate, cellulose acetate propionate, silicone (silicone) resins, acrylamide resins, epoxy resins, or copolymers thereof, or mixtures thereof. Among these, acrylic resins, vinyl chloride resins, cellulose resins, polyester resins, and polyurethane resins are preferred. Alternatively, copolymers thereof, or mixtures thereof, may be used.

[0140] In the non-aqueous ink composition of this embodiment, from the viewpoint of improving water resistance, solvent resistance, and tensile strength, it is preferable to contain at least one type of acrylic resin, a copolymer resin of vinyl chloride and vinyl acetate (vinyl chloride-vinyl acetate). Furthermore, if the non-aqueous ink composition contains at least one type of acrylic resin, a copolymer resin of vinyl chloride and vinyl acetate (vinyl chloride-vinyl acetate), then when the non-aqueous ink composition is a non-aqueous inkjet ink composition that is sprayed onto the surface of a substrate by inkjet printing, the ejection responsiveness and ejection stability during high-speed recording can be improved.

[0141] As for acrylic resins, there is no particular limitation as long as they are the main component of the monomers constituting (meth)acrylate monomers. They can be homopolymers of one type of free radical polymerizable monomer, or copolymers using two or more types of free radical polymerizable monomers. Specifically, the preferred acrylic resin for the non-aqueous ink composition of this embodiment is a methyl methacrylate homopolymer, or a copolymer of methyl methacrylate with at least one compound selected from butyl methacrylate, ethoxyethyl methacrylate, and benzyl methacrylate. Furthermore, commercially available (meth)acrylate resins include, for example, Rohm and Haas's "Paraloid B99N," "Paraloid B60," "Paraloid B66," and "Paraloid B82."

[0142] Vinyl chloride-based resins can be homopolymers composed of vinyl chloride monomers or copolymers using two or more polymerizable monomers. Examples of vinyl chloride-vinyl acetate copolymers include, for instance, vinyl chloride-vinyl acetate copolymer resins. Vinyl chloride-vinyl acetate copolymer resins are polymers of vinyl chloride monomers and vinyl acetate monomers. Examples of vinyl chloride-vinyl acetate copolymer resins include vinyl chloride-vinyl acetate copolymers, vinyl chloride / vinyl acetate / maleic acid copolymers, vinyl chloride / vinyl acetate / vinyl alcohol copolymers, vinyl chloride / vinyl acetate / hydroxyalkyl acrylate copolymers, and mixtures thereof. These vinyl chloride-vinyl acetate copolymer resins are available and used from Nissin Chemical Industries, Ltd. under trade names such as "SOLBIN C", "SOLBIN CL", "SOLBIN CNL", "SOLBIN CLL", "SOLBIN CLL2", "SOLBIN C5R", "SOLBIN TA2", "SOLBIN TA3", "SOLBIN A", "SOLBIN AL", "SOLBIN TA5R", and "SOLBIN M5".

[0143] Cellulose-based resins refer to resins with a cellulose skeleton obtained by introducing functional groups into cellulose by biological or chemical means. For example, as cellulose-based resins, cellulose acetate alkylate resins such as cellulose acetate butyrate resin, cellulose acetate propionate resin, and cellulose acetate propionate butyrate resin (Japanese: セルロースアセテートアルキレート樹脂), cellulose acetate resin, nitrocellulose resin, and mixtures thereof can be cited. As the above-mentioned cellulose resins, they can be obtained and used under the trade names of "CAB551-0.01", "CAB551-0.2", "CAB553-0.4", "CAB531-1", "CAB381-0.1", "CAB381-0.5", "CAB381-2", "CAB381-20", "CAP504", "CAP482-0.5", etc. of Eastman Company.

[0144] Polyester-based resins refer to resins that contain at least structural units obtained by polycondensing an alcohol component and a carboxylic acid component. Polyester-based resins can include modified polyester-based resins. As the above-mentioned polyester-based resins, they can be obtained and used under the trade names of "VYLON226", "VYLON270", "VYLON560", "VYLON600", "VYLON630", "VYLON660", "VYLON885", "VYLONGK250", "VYLONGK810", "VYLON GK890", etc. of Toyobo Company, and "elitleUE-3200", "elitleUE-3285", "elitleUE-3320", "elitleUE-9800", "elitleUE-9885", etc. of Unitika Company.

[0145] Polyurethane-based resins refer to resins that contain at least structural units obtained by copolymerizing an alcohol component and an isocyanate component. Polyurethane-based resins can include polyurethane-based resins modified with polyester, polyether, and caprolactone. As the above-mentioned polyurethane-based resins, they can be obtained and used under the trade names of "UREANO KL-424", "UREANO KL-564", "UREANO KL-593", "UREANO 3262", etc. of Arakawa Chemical Industries Co., Ltd., and "Pandex372E", "Pandex 390E", "Pandex394E", "Pandex 304", "Pandex305E", "Pandex P-870", "Pandex P-910", "Pandex P-895", "Pandex 4030", "Pandex 4110", etc. of DIC Corporation.

[0146] Furthermore, these acrylic resins, vinyl chloride resins, cellulose resins, polyester resins, and polyurethane resins can be used individually, but it is preferable to use two in combination, and more preferably to use a resin obtained by mixing acrylic resins and vinyl chloride resins. The ratio of acrylic resins to vinyl chloride resins can be controlled to meet the requirements of non-aqueous ink compositions, such as color development, drying properties, film properties, and printability. When mixing acrylic resins and vinyl chloride resins, the mixing ratio is not particularly limited and can be appropriately varied.

[0147] The percentage by mass of resin contained in the total amount of the non-aqueous ink composition in this embodiment is not particularly limited. For example, it is preferably 0.05% by mass or more in the total amount of the non-aqueous ink composition, more preferably 0.1% by mass or more, further preferably 0.5% by mass or more, and more preferably 1% by mass or more. The percentage by mass of resin contained in the total amount of the non-aqueous ink composition is not particularly limited. For example, it is preferably 20% by mass or less in the non-aqueous ink composition, and more preferably 15% by mass or less.

[0148] [Dispersant]

[0149] In the non-aqueous ink composition contained in the ink group of this embodiment, a dispersant may be used as needed. Any dispersant used in non-aqueous ink compositions may be used as a dispersant. A polymeric dispersant may be used. Such a dispersant has a main chain composed of polyester, polyacrylic acid, polyurethane, polyamine, polycaprolactone, etc., and has polar groups such as amino, carboxyl, sulfonyl, and hydroxyl groups as side chains. For example, dispersants based on polyacrylic acid can be used such as Disperbyk-2000, 2001, 2008, 2009, 2010, 2020, 2020N, ​​2022, 2025, 2050, 2070, 2095, 2150, 2151, 2155, 2163, 2164, BYKJET-9130, 9131, 9132, 9133, 9151 (manufactured by BYK-Chemie), Efka PX4310, PX4320, PX4330, PA4401, 4402, PA4403, 4570, 7411, 7477, PX4700, PX4701 (manufactured by BASF), and TREPLUS. D-1200, D-1410, D-1420, MD-1000 (manufactured by Otsuka Chemicals), FlowlenDOPA-15BHFS, 17HF, 22, G-700, 900, NC-500, GW-1500 (manufactured by Kyoeisha Chemicals Co., Ltd.), etc. Polycaprolactone-based dispersants include, for example, AJISPER PB821, PB822, PB881 (manufactured by Ajinomoto Fine-Techno Co., Ltd.), Hinoact KF-1000, T-6000, T-7000, T-8000, T-8000E, T-9050 (manufactured by Kawaken FineChemicals Co., Ltd.), Solsperse 20000, 24000, 32000, 32500, 32550, 32600, 33000, 33500, 34000, 35200, 36000, 37500, 39000, 71000, 76400, 76500, 86000, 88000, J180, J200 (manufactured by Lubrizol Co., Ltd.), TEGO. Dispers 652, 655, 685, 688, 690 (made by Evonik Japan), etc.Preferred dispersants include BYKJET-9130, 9131, 9132, 9133, 9151, EfkaPX4310, PX4320, PX4330, PX4700, PX4701, Solsperse 20000, 24000, 32000, 33000, 33500, 34000, 35200, 39000, 71000, 76500, 86000, 88000, J180, J200, TEGO Dispers 655, 685, 688, 690, etc. They can be used alone or in mixtures.

[0150] [Dispersing agent]

[0151] In the non-aqueous ink composition contained in the ink group of this embodiment, a dispersing aid may be used as needed. The dispersing aid adsorbs onto the surface of the pigment, and its functional groups increase the affinity with the organic solvent and dispersant in the non-aqueous ink composition, thereby improving dispersion stability. As a dispersing aid, known pigment derivatives having functional groups such as acidic groups, basic groups, and neutral groups in the organic pigment residues can be used.

[0152] [surfactant]

[0153] In the non-aqueous ink composition of this embodiment, surfactants may be added for the purpose of suppressing the volatilization of the ink composition in the nozzle section, tube, or other equipment, preventing curing, or preventing redissolution during curing, or for the purpose of reducing surface tension and improving wettability with the recording medium (substrate). Examples of nonionic polyoxyalkylene ethers include P-208, P-210, P-213, E-202S, E-205S, E-215, K-204, K-220, S-207, S-215, A-10R, A-13P, NC-203, NC-207 (manufactured by Nippon Yushu Co., Ltd.), EMULGEN 106, 108, 707, 709, A-90, A-60 (manufactured by Kao Corporation), Flowlen G-70, D-90, TG-740W (manufactured by Kyoei Chemical Co., Ltd.), POEM J-0081HV (manufactured by RIKEN VITAMIN Co., Ltd.), Adekatol NP-620, NP-650, NP-660, NP-675, NP-683, NP-686, and Adekacol. Fluorinated surfactants such as CS-141E, TS-230E (manufactured by ADEKA Co., Ltd.), SORGEN 30V, 40, TW-20, TW-80, and NoigenCX-100 (manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.) are preferred as fluorinated surfactants. Specific examples include BYK-340 (manufactured by BYK-Chemie Japan Co., Ltd.). Polyester-modified silicone and polyether-modified silicone are preferred as silicone surfactants. Specific examples include BYK-313, 315N, 322, 326, 331, 347, 348, BYK-UV3500, 3510, 3530, and 3570 (all BYK-Chemie). As acetylenic diol surfactants, specific examples include SURFYNOL (registered trademark) 82, 104, 465, 485, TG (all manufactured by Air Products Japan), OLFINE (registered trademark) STG, E1010 (all manufactured by Nisshin Chemical Co., Ltd.), etc.

[0154] As a surfactant, it is not limited to the above-mentioned types. Any surfactant from anionic, cationic, amphoteric, or nonionic systems can be used, and the appropriate type can be selected according to the purpose of addition.

[0155] [Other ingredients]

[0156] The non-aqueous ink composition of this embodiment may include, as an arbitrary component, known additives such as antioxidants, stabilizers such as UV absorbers, epoxides, polycarboxylic acids, surface conditioners, leveling agents (acrylic, silicone, etc.), defoamers, pH adjusters, bactericides, preservatives, deodorizers, charge regulators, and wetting agents. Specific examples of antioxidants include hindered phenolic antioxidants, amine antioxidants, phosphorus antioxidants, sulfur antioxidants, and hydrazine antioxidants. Specifically, examples include BHA (2,3-butyl-4-oxyanisole) and BHT (2,6-di-tert-butyl-p-cresol). Furthermore, benzophenone compounds or benzotriazole compounds may be used as UV absorbers. Specific examples of epoxides include epoxy glycerol esters, epoxy fatty acid monoesters, and epoxy hexahydrophthalates, specifically ADK CIZER O-130P and ADK CIZER O-180A (manufactured by ADEKA). Specific examples of polycarboxylic acids include citric acid and maleic acid.

[0157] [Substrate]

[0158] The substrate (recording medium) that can be used in the non-aqueous ink composition of this embodiment is not particularly limited. It can be a resin substrate, a non-absorbent substrate such as a metal plate or glass, an absorbent substrate such as paper or cloth, or a substrate with a surface coating such as a substrate having a receiving layer. Various substrates can be used. Among them, the non-aqueous ink composition of this embodiment is an aqueous non-aqueous ink composition, so a resin substrate is suitable. As the resin, polyvinyl chloride polymers, acrylics, PET, polycarbonate, PE, PP, etc. can be used. A substrate (recording medium) with a surface formed of a rigid or flexible polyvinyl chloride polymer is particularly preferred. Examples of substrates (recording media) with a surface containing a polyvinyl chloride polymer include polyvinyl chloride materials (films or sheets).

[0159] Furthermore, the non-aqueous ink composition of this embodiment exhibits excellent recording and drying properties, and good post-processing properties of the recorded material. Therefore, it is more preferable to use a resin substrate (so-called lamination resin substrate) on which a film is to be bonded to the recording surface of the recorded material, and particularly preferable to use a polyvinyl chloride polymer substrate for lamination.

[0160] <The Non-Aqueous Ink Composition of the Second Embodiment>

[0161] The non-aqueous ink composition of this embodiment contains an organic solvent, characterized in that it contains at least one organic solvent selected from alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with 6 or more members (b3), and a resin with a weight-average absolute molecular weight of 15,000 or more and 80,000 or less.

[0162] Such a non-aqueous ink composition can be used on various substrates. For example, even when using a resin substrate with an adhesive layer on one side, and recording (printing) the non-aqueous ink composition of the present invention on the surface of a substrate without the adhesive layer, it is possible to suppress the deterioration of the adhesive layer's adhesion (the adhesion between the recording and the adhered object), and even when the recording is stretched, it is possible to effectively suppress the whitening of the decorative layer.

[0163] Furthermore, resins with a weight-average absolute molecular weight of 15,000 or more and 80,000 or less have high weight-average absolute molecular weights and low solubility in organic solvents, making it difficult to dissolve the resin in non-aqueous ink compositions. Even if temporarily dissolved, the resin is prone to precipitation. Therefore, for example, in the case of a non-aqueous inkjet ink composition that is sprayed onto the surface of a substrate by inkjet printing, resin precipitates may sometimes adhere to the inkjet nozzle, causing nozzle defects or bending, thereby reducing ejection stability and preventing normal printing. However, the non-aqueous ink composition of this embodiment, which contains at least one organic solvent (b) selected from alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3), can dissolve resins with high weight-average absolute molecular weights and maintain ejection stability.

[0164] The moisture content is preferably 5.0% by mass or less in the total amount of the non-aqueous ink composition, more preferably 3.0% by mass or less, even more preferably 1.0% by mass or less, and even more preferably 0.5% by mass or less. In particular, the non-aqueous ink composition of this embodiment contains a resin with a large weight-average absolute molecular weight that can reduce the spraying stability and storage stability of the non-aqueous ink composition, but by containing the organic solvent (b) described later and by ensuring that the moisture content is 5.0% by mass or less in the total amount of the non-aqueous ink composition, spraying stability and storage stability can be maintained.

[0165] The components contained in the non-aqueous ink composition of this embodiment will be described below.

[0166] [Organic solvents]

[0167] Organic solvents contain organic solvents (b).

[0168] Organic solvent (b): at least one selected from alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with more than 6 members (b3).

[0169] The following will describe organic solvent (b) and other organic solvents contained in organic solvents in more detail.

[0170] (Organic solvent(b))

[0171] The organic solvent (b) is selected from at least one of alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3). Compared to non-aqueous ink compositions containing five-membered ring lactone solvents, this organic solvent (b) exhibits lower permeability to the substrate. Therefore, it is possible to effectively suppress the degradation of the adhesive properties (adhesion between the recording material and the substrate) of the adhesive layer caused by the penetration of the non-aqueous ink composition from the resin substrate to the adhesive layer.

[0172] Furthermore, this organic solvent (b) is a solvent that penetrates the substrate to a certain extent, resulting in faster drying on the substrate surface. Therefore, ink compositions containing organic solvent (b) exhibit similarly high drying properties as non-aqueous ink compositions containing 5-membered ring lactone solvents, and exhibit less ink bleeding during printing (recording), resulting in clear printing. Such an effect of less ink bleeding cannot be achieved simply by selecting a solvent with a low boiling point to improve drying performance.

[0173] Furthermore, by containing at least one organic solvent (b) selected from alkylamide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3), high molecular weight resins can be effectively dissolved in non-aqueous ink compositions.

[0174] The alkylamide solvent (b1), cyclic amide solvent (b2), and lactone solvent with a 6-membered ring or more (b3) are the same as the organic solvent (b) contained in the non-aqueous ink composition of the first embodiment described above. The preferred alkylamide solvent (b1), cyclic amide solvent (b2), and lactone solvent with a 6-membered ring or more (b3) are also the same as the organic solvent (b) contained in the non-aqueous ink composition of the first embodiment described above.

[0175] A non-aqueous ink composition containing at least one of the following organic solvents (b): alkyl amide solvent (b1), cyclic amide solvent (b2), and lactone solvent with a 6-membered ring or more (b3), becomes a non-aqueous ink composition that exhibits the effects of the present invention. From the viewpoint of particularly maximizing the effects of the present invention, it is preferable to contain at least one of the following organic solvents (b): alkyl amide solvent (b1) and cyclic amide solvent (b2), and it is particularly preferable to contain alkyl amide solvent (b1) as organic solvent (b).

[0176] There is no particular limit to the upper limit of the content of organic solvent (b) (selected from at least one of alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with more than 6 members (b3)). It is preferred to contain 30.0% by mass or less in the total amount of non-aqueous ink composition, more preferably 25.0% by mass or less, even more preferably 20.0% by mass or less, and even more preferably 15.0% by mass or less.

[0177] There is no particular limitation on the lower limit of the content of organic solvent (b) (selected from at least one of alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with more than 6 members (b3)), but it is preferred to contain 3.0% by mass or more in the total amount of ink composition, and more preferably 5.0% by mass or more.

[0178] It should be noted that the upper and lower limits of the content of the aforementioned organic solvent (b) are common to all alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with 6 or more members (b3). In particular, when the organic solvent (b) is a lactone solvent with 6 or more members (b3), it is most preferable that it contains 5.0% by mass or more and 15.0% by mass or less in the total amount of the non-aqueous ink composition.

[0179] It should be noted that, preferably, before mixing the organic solvent (b) (selected from at least one of alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with 6 or more members (b3)) with other components, the content of impurities from the organic solvent (b) should be set to be 0.5% by mass or less in the total amount of organic solvent (b). For example, when recording a non-aqueous ink composition on a resin substrate with an adhesive layer on one side, sometimes low-boiling-point impurities contained in the organic solvent (b) can penetrate from the decorative layer to the adhesive layer on the back side, deteriorating the adhesion of the adhesive layer (the adhesion between the recorded material and the adhered object). In addition, due to the low-boiling-point impurities contained in the organic solvent (b), sometimes adverse conditions such as dissolution and swelling can occur in the plastics and adhesives used in printer components such as inkjet heads. By pre-setting the organic solvent (b) to have an impurity content of less than 0.5% by mass in the total amount of organic solvent (b) before mixing with other components, the above-mentioned problems can be solved, thus creating a non-aqueous ink composition that further enhances the effects of the present invention.

[0180] As a method for purifying organic solvent (b), it can be achieved by repeatedly distilling the organic solvent (b), reducing the temperature step of distillation to minimize the presence of impurities, or repeatedly extracting. In addition, in industrial manufacturing processes, besides the above-mentioned processes, it can also be achieved by implementing pollution suppression measures.

[0181] (Other organic solvents)

[0182] The organic solvent may contain organic solvents other than those described in organic solvent (b). Specifically, examples include dialkyl ethers of glycols in which the OH groups at both ends are replaced by alkyl groups, monoalkyl ethers of glycols in which one OH group is replaced by an alkyl group, carbonates, etc.

[0183] Diol dialkyl ethers, for example, can be represented by the diol dialkyl ether shown in the following formula (1).

[0184] [Chemical Formula 9]

[0185]

[0186] (In formula (1), R1 and R3 are alkyl groups, and R2 represents ethylene or propylene. n represents an integer from 2 to 4.)

[0187] Specifically, examples of dialkyl glycol ethers include ethylene glycol dibutyl ether, ethylene glycol dipropyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dipropyl ether, diethylene glycol methyl propyl ether, diethylene glycol methyl isopropyl ether, diethylene glycol dibutyl ether, diethylene glycol methyl butyl ether, diethylene glycol ethyl butyl ether, diethylene glycol methyl-2-ethylhexyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, and triethylene glycol methyl ethyl ether. Tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol methyl ethyl ether, propylene glycol diethyl ether, propylene glycol methyl ethyl ether, propylene glycol methyl propyl ether, propylene glycol methyl butyl ether, propylene glycol methyl-2-ethylhexyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol methyl ethyl ether, dipropylene glycol methyl propyl ether, dipropylene glycol dipropyl ether, dipropylene glycol methyl butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, tripropylene glycol methyl ethyl ether, etc.

[0188] Among the dialkyl glycol ethers, the preferred dialkyl glycol ethers are those in formula (1) where the total number of carbon atoms in R1 and R3 is 2 or more and 8 or less, more preferably dialkyl glycol ethers with 2 or more and 6 or less, and even more preferably dialkyl glycol ethers in formula (1) where R1 is methyl or ethyl and R3 is ethyl, and / or dialkyl glycol ethers in formula (1) where R1 and R3 are methyl and R2 is propylene.

[0189] Dialkyl glycol ethers, in which the total number of carbon atoms in R1 and R3 is 2 or more and 6 or less, are more volatile than, for example, diethylene glycol dibutyl ether (in which the total number of carbon atoms in R1 and R3 is 8), and therefore become non-aqueous ink compositions with excellent recording and drying properties.

[0190] Examples of dialkyl glycol ethers in which the total number of carbon atoms in R1 and R3 is 2 or more and 6 or less include diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, diethylene glycol methyl isopropyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, and tetraethylene glycol diethyl ether.

[0191] Furthermore, dialkyl glycol ethers in formula (1) where R1 is methyl or ethyl and R3 is ethyl, and / or dialkyl glycol ethers in formula (1) where R1 and R3 are methyl and R2 is propylene, have lower permeability compared to, for example, diethylene glycol dimethyl ether (where R1 and R3 are methyl and R2 is ethylene). Therefore, for example, even when using a resin substrate with an adhesive layer on one side, and recording (printing) a non-aqueous ink composition on the substrate surface without the adhesive layer, the degradation of the adhesive properties (adhesion between the recorded material and the adhered object) of the adhesive layer can be more effectively suppressed.

[0192] Examples of dialkyl glycol ethers in formula (1) where R1 is methyl or ethyl and R3 is ethyl include diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, triethylene glycol diethyl ether, tetraethylene glycol diethyl ether, etc. Examples of dialkyl glycol ethers in formula (1) where R1 and R3 are methyl and R2 is propylene glycol include dipropylene glycol dimethyl ether.

[0193] Furthermore, dialkyl glycol ethers are prone to producing impurities such as polymers, by-reactants, and decomposition products during manufacturing. For example, the impurity content in commercially available dialkyl glycol ethers can sometimes reach about 10% by mass of the total dialkyl glycol ether. Therefore, it is preferable to pre-set the dialkyl glycol ether to contain impurities of 0.5% by mass or less of the total dialkyl glycol ether before mixing it with other components. Sometimes, the odor can be deteriorated due to low-boiling-point impurities contained in the dialkyl glycol ether. In addition, for example, when recording a non-aqueous ink composition on a resin substrate with an adhesive layer on one side, low-boiling-point impurities contained in the dialkyl glycol ether can sometimes penetrate from the decorative layer to the adhesive layer on the back side, deteriorating the adhesion of the adhesive layer (the adhesion between the recorded material and the adhered object). Furthermore, due to the low-boiling-point impurities contained in the dialkyl glycol ether, problems such as dissolution and swelling can sometimes occur in the plastics and adhesives used in printer components such as inkjet heads. Furthermore, when the impurities contained in the glycol dialkyl ether are high-boiling-point substances, bleeding of the printed text may sometimes occur due to reduced drying properties of the non-aqueous ink composition. By pre-setting the glycol dialkyl ether to ensure that the content of impurities from the glycol dialkyl ether is less than 0.5% by mass in the total glycol dialkyl ether before mixing with other components, the above-mentioned problem can be solved, thus creating a non-aqueous ink composition that further enhances the effects of the present invention.

[0194] The impurities contained in the dialkyl glycol ether are the same as those contained in the organic solvent (a) contained in the non-aqueous ink composition of the first embodiment described above. The purification method is also the same.

[0195] When the dialkyl glycol ether is present, there is no particular limitation on the lower limit of the content of the dialkyl glycol ether, but it is preferable to contain 30.0% by mass or more in the total amount of the non-aqueous ink composition, more preferably 40.0% by mass or more, and even more preferably 50.0% by mass or more.

[0196] There is no particular limit to the content of dialkyl glycol ethers, but it is preferred to contain 90.0% by mass or less in the total amount of the non-aqueous ink composition, and more preferably 80.0% by mass or less.

[0197] Examples of glycol monoalkyl ethers include ethylene glycol mono-n-butyl ether, ethylene glycol mono-isobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol mono-2-ethylhexyl ether, diethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, triethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, tetraethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, and tetraethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, ... 2-Ethylhexyl ether, propylene glycol mono-n-butyl ether, propylene glycol mono-isobutyl ether, propylene glycol mono-tert-butyl ether, propylene glycol mono-2-ethylhexyl ether, dipropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, tripropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl) ether, tetrapropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl) ether, etc.

[0198] Examples of carbonates include ethylene carbonate and propylene carbonate.

[0199] In addition, it may contain organic solvents other than those mentioned above. Specifically, examples include cyclic esters such as γ-butyrolactone, γ-valactone, γ-caprolactone, γ-heptanolactone, γ-octanolactone, γ-nonanolactone, γ-decanolactone, and γ-undecanolactone; oxazolidinone solvents such as 3-methyl-2-oxazolidinone, 3-ethyl-2-oxazolidinone, and N-vinylmethyloxazolidinone; acetate solvents such as triethylene glycol butyl ether acetate, ethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol methyl ether acetate, diethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, 1-methoxy-2-propyl acetate, 2-methylbutyl acetate, 3-methoxybutyl ether acetate, and cyclohexyl acetate; 3-methyl Amide solvents that differ from alkylamide solvents (b1) and cyclic amide solvents (b2), such as oxypropionamide, 3-butoxypropionamide, N,N-dimethyl-3-methoxypropionamide, N,N-dibutyl-3-methoxypropionamide, N,N-dibutyl-3-butoxypropionamide, and N,N-dimethyl-3-butoxypropionamide; alkyl alcohols with 1 to 5 carbon atoms, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, isobutanol, and n-pentanol; monohydric alcohol solvents such as 3-methoxy-3-methyl-1-butanol, 3-methoxy-1-propanol, 1-methoxy-2-propanol, and 3-methoxy-n-butanol; acetone, diacetone alcohol, methyl ethyl ketone, and methyl n-butanol. Ketones or ketone alcohols such as propyl ketone, methyl isopropyl ketone, methyl n-butyl ketone, methyl isobutyl ketone, methyl n-pentyl ketone, methyl hexyl ketone, methyl isopentyl ketone, diethyl ketone, ethyl n-propyl ketone, ethyl isopropyl ketone, ethyl n-butyl ketone, ethyl isobutyl ketone, di-n-propyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methyl cyclohexanone, isophorone, and acetyl ketone; ethers such as tetrahydrofuran and dioxane; copolymers of polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-propanediol, isobutylene glycol, triethylene glycol, tripropylene glycol, tetraethylene glycol, 1,3-propanediol, 2-methyl-1,2-propanediol, and 2-methyl-1,2-propanediol. Diols such as alcohols, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, and 2-methyl-2,4-pentanediol; triols such as glycerol, trimethylolethane, trimethylolpropane, and 1,2,6-hexanetriol; tetraols such as mesoerythritol and pentaerythritol; monoethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, N-ethylethanolamine, N-butylethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, and N-butyldiethanolamine; and alkanolamines such as ethanolamines.Acetic acid esters such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, hexyl acetate, and octyl acetate; lactic acid esters such as methyl lactate, ethyl lactate, butyl lactate, propyl lactate, ethylhexyl lactate, pentyl lactate, and isoamyl lactate; saturated hydrocarbons such as n-hexane, isohexane, n-nonane, isononane, dodecane, and isododecane; unsaturated hydrocarbons such as 1-hexene, 1-heptene, and 1-octene; cyclohexene, cyclohexene, and cyclohexene. Resins include cyclic unsaturated hydrocarbons such as hepten, cyclooctene, 1,3,5,7-cyclooctatetraene, and cyclododecene; aromatic hydrocarbons such as benzene, toluene, and xylene; morpholine solvents such as N-methylmorpholine, N-ethylmorpholine, and N-formylmorpholine; terpene solvents; and dimethyl oxalate, diethyl oxalate, dimethyl malonate, diethyl malonate, dimethyl succinate, diethyl succinate, dimethyl glutarate, and diethyl glutarate. Solvents with appropriate HLB values ​​are preferably selected based on the combined resins and dispersants.

[0200] Additionally, the ink composition may contain a 5-membered ring lactone solvent, but it is preferable that it does not contain a 5-membered ring lactone solvent. When a 5-membered ring lactone solvent is present, its content in the total amount of the non-aqueous ink composition is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, even more preferably 1.0% by mass or less, and even more preferably not present.

[0201] Examples of 5-membered ring lactone solvents include γ-butyrolactone, γ-valerolactone, γ-caprolactone, and γ-heptylactone.

[0202] [Colorant]

[0203] Regarding the colorant, it is the same as the colorant contained in the non-aqueous ink composition of the first embodiment described above. The preferred pigment content is also the same.

[0204] [Resin]

[0205] The non-aqueous ink composition of this embodiment is characterized by containing a resin with a weight-average absolute molecular weight of 15,000 or more and 80,000 or less. Therefore, even when the recording is stretched, whitening of the decorative layer can be effectively suppressed. Such a high weight-average absolute molecular weight resin has low solubility in organic solvents, but if the non-aqueous ink composition of this embodiment contains at least one organic solvent (b) selected from alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with six or more members (b3), then the high weight-average absolute molecular weight resin can be dissolved, achieving a state that maintains storage stability and spray stability, and effectively suppressing whitening of the decorative layer.

[0206] Here, weight-average absolute molecular weight refers to the weight-average absolute molecular weight determined by gel permeation chromatography-multi-angle light scattering (GPC-MALS). The weight-average absolute molecular weight can be determined using a GPC (Waters Corporation, Alliance GPC) equipped with a TSKgel column (Tosoh Corporation) and a multi-angle light scattering detector (Wyatt Corporation, miniDawn TREOS), with THF used as the developing solvent. This weight-average absolute molecular weight differs from the weight-average relative molecular weight obtained using the polystyrene conversion value (relative value) obtained by conventional GPC methods.

[0207] Regarding the weight-average relative molecular weight calculated using polystyrene conversion values ​​(relative values), due to differences in molecular structure between the resin being tested and the polystyrene used as a standard, as well as the influence of column adsorption, it may not be able to accurately determine the molecular weight and amount of gel component in the resin being tested. Therefore, if the weight-average absolute molecular weight is determined by GPC equipped with a specified column and a multi-angle light scattering detector, it can serve as an indicator of the resin's true weight-average molecular weight.

[0208] There are no particular restrictions on the weight-average absolute molecular weight of the resin, as long as it is between 15,000 and 80,000. The lower limit of the weight-average absolute molecular weight of the resin is preferably 25,000 or higher, and more preferably 32,500 or higher. This further improves the tensile strength of the decorative layer and effectively suppresses whitening of the decorative layer.

[0209] The upper limit of the weight-average absolute molecular weight of the resin is preferably 70,000 or less, more preferably 50,000 or less. Since the ejection stability of the non-aqueous ink composition is improved, for example, when the non-aqueous ink composition is a non-aqueous inkjet ink composition that is ejected onto the surface of a substrate by inkjet printing, the printing quality can be improved.

[0210] As a resin, there are no particular limitations; for example, acrylic resins, polystyrene resins, polyester resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, polyethylene resins, polyurethane resins, rosin-modified resins, phenolic resins, terpene resins, polyamide resins, vinyltoluene-α-methylstyrene copolymers, ethylene-vinyl acetate copolymers, cellulose acetate butyrate, cellulose acetate propionate, silicone (silicone) resins, acrylamide resins, epoxy resins, or copolymers thereof, or mixtures thereof, can be used.

[0211] In the non-aqueous ink composition of this embodiment, it is preferable to include at least one selected from acrylic resins, vinyl chloride resins, and cellulose resins, from the perspective of improving water resistance, solvent resistance, and tensile strength. Furthermore, when used as an inkjet ink, it can improve ejection responsiveness and ejection stability during high-speed recording.

[0212] Acrylic resins are not particularly limited to any resin that is a main component of the monomer constituting (meth)acrylate monomer; examples of resins similar to those in the above-described non-aqueous ink compositions can be given. The acrylic resin can be a homopolymer of one free-radical polymerizable monomer, or any copolymer using two or more free-radical polymerizable monomers. Specifically, the preferred acrylic resin for the non-aqueous ink composition of this embodiment is a methyl methacrylate homopolymer, or a copolymer of methyl methacrylate with at least one compound selected from butyl methacrylate, ethoxyethyl methacrylate, and benzyl methacrylate.

[0213] Vinyl chloride-based resins can be homopolymers composed of vinyl chloride monomers or copolymers using two or more polymerizable monomers. Examples of vinyl chloride-based copolymers include vinyl chloride-vinyl acetate copolymer resins. Vinyl chloride-vinyl acetate copolymer resins are polymers of vinyl chloride monomers and vinyl acetate monomers. Examples of vinyl chloride-vinyl acetate copolymer resins include vinyl chloride-vinyl acetate copolymers, vinyl chloride / vinyl acetate / maleic acid copolymers, vinyl chloride / vinyl acetate / vinyl alcohol copolymers, vinyl chloride / vinyl acetate / hydroxyalkyl acrylate copolymers, and mixtures thereof.

[0214] Cellulose-based resins refer to resins with a cellulose backbone obtained by introducing functional groups into cellulose as a raw material through biological or chemical means. Examples of cellulose-based resins include cellulose acetate butyrate resin, cellulose acetate propionate resin, cellulose acetate propionate butyrate resin, alkylated cellulose acetate resin, cellulose acetate resin, nitrocellulose resin, and mixtures thereof.

[0215] The resin content in the total amount of the non-aqueous ink composition of this embodiment is not particularly limited. For example, it is preferably 0.05% by mass or more in the total amount of the non-aqueous ink composition, more preferably 0.1% by mass or more, further preferably 0.5% by mass or more, and more preferably 1% by mass or more. The percentage by mass of resin in the total amount of the non-aqueous ink composition is not particularly limited. For example, it is preferably 20% by mass or less in the non-aqueous ink composition, more preferably 15% by mass or less.

[0216] [Dispersant]

[0217] Regarding the dispersant, it is the same as the dispersant contained in the non-aqueous ink composition of the first embodiment described above.

[0218] [Dispersing agent]

[0219] Regarding the dispersing agent, it is the same as the dispersing agent contained in the non-aqueous ink composition of the first embodiment described above.

[0220] [surfactant]

[0221] Regarding the surfactant, it is the same as the surfactant contained in the non-aqueous ink composition of the first embodiment described above.

[0222] [Other ingredients]

[0223] The non-aqueous ink composition of this embodiment may include, as any known additives, such as antioxidants, UV absorbers, stabilizers, epoxides, polycarboxylic acids, surface conditioners, leveling agents (acrylic, silicone, etc.), defoamers, pH adjusters, bactericides, preservatives, deodorizers, charge regulators, and wetting agents. Other components are the same as the dispersant contained in the non-aqueous ink composition of the first embodiment described above.

[0224] [Substrate]

[0225] As the substrate (recording medium) that can be used in the non-aqueous ink composition of this embodiment, the same substrate (recording medium) that can be used in the non-aqueous ink composition of the first embodiment described above can be used.

[0226] Furthermore, the non-aqueous ink composition of this embodiment, by using a resin substrate (a resin substrate for lamination) with an adhesive layer on one side, can more effectively suppress film peeling and deterioration of the adhesive layer's adhesion (adhesion between the recording medium and the substrate). Therefore, the substrate (recording medium) used in the non-aqueous ink composition of this embodiment is not particularly limited, but a resin substrate with an adhesive layer on one side is preferred, and a polyvinyl chloride material with an adhesive layer on one side is particularly preferred.

[0227] <Recording Method Using Ink Composition>

[0228] The recording method for recording on the surface of a substrate (recording medium) using the non-aqueous ink composition of this embodiment (the non-aqueous ink composition of the first embodiment or the non-aqueous ink composition of the second embodiment described above) is not particularly limited. Examples include spraying, coating, inkjet, gravure, and flexographic printing.

[0229] Preferably, the ink is sprayed onto the surface of the substrate using an inkjet method. The non-aqueous ink composition of this embodiment exhibits less solubility and swelling in plastic components and adhesives, thus demonstrating good adaptability to components such as inkjet printheads, which may be a problem in non-aqueous ink compositions for inkjet printing. Furthermore, since the non-aqueous ink composition of the first embodiment described above has good drying properties, it is possible to efficiently manufacture recording materials with good post-processing properties using an inkjet method.

[0230] The inkjet printer used in the inkjet method can be a conventionally known inkjet printer. For example, the VersaArt RE-640 or an inkjet printer manufactured by Roland DG Co., Ltd. can be used.

[0231] Furthermore, the non-aqueous ink composition of this embodiment can also be used for inks of various colors such as yellow, magenta, cyan, black, light magenta, light cyan, light black, orange, green, red, and white. There are no particular limitations on the order of the printed colors, the position of the inkjet head, or the overall composition. Additionally, the inkjet printer may or may not include a winding mechanism for the recording medium (substrate), a drying mechanism for drying the substrate surface, and an ink circulation mechanism.

[0232] <Recording objects and methods of manufacturing recording objects>

[0233] The recording object can also be manufactured using the non-aqueous ink composition of this embodiment (the non-aqueous ink composition of the first embodiment or the non-aqueous ink composition of the second embodiment described above). The method for manufacturing the recording object is not particularly limited, and it can be manufactured using the methods exemplified in the recording methods using the above-described ink compositions. Preferably, it is manufactured by inkjet spraying onto the surface of a substrate.

[0234] The non-aqueous ink composition of the first embodiment described above has high drying properties on the substrate surface and good post-processing properties of the resulting record. Therefore, if a laminate (record) is formed by coating (spraying) the non-aqueous ink composition of this embodiment onto the surface of a resin substrate opposite to the adhesive layer using a resin substrate for lamination, and a laminate film is provided on the surface of the decorative layer, the floating of the laminated film can be effectively suppressed, and thus the post-processing properties of the record are good.

[0235] Since the non-aqueous ink composition of the second embodiment described above has low permeability to the resin substrate, even when using a resin substrate with an adhesive layer on one side, for example, and recording (printing) the non-aqueous ink composition of this embodiment on the substrate surface on the side without the adhesive layer, the deterioration of the adhesiveness (adhesion between the recorded object and the adhered object) of the adhesive layer can be suppressed.

[0236] Furthermore, if the non-aqueous ink composition of the second embodiment contains at least one organic solvent (b) selected from alkyl amide solvents (b1), cyclic amide solvents (b2), and lactone solvents with 6 or more members (b3), it can dissolve resins with high weight-average absolute molecular weight, thus maintaining the preservation stability and ejection stability that may be problems in inkjet ink compositions, and by containing resins with high weight-average absolute molecular weight, it can effectively suppress the whitening of the decorative layer even when the recorded material is stretched.

[0237] Example

[0238] The present invention will now be described in more detail by way of examples, but the present invention is not limited in any way by these descriptions.

[0239] [Non-aqueous ink composition of the first embodiment]

[0240] 1. Resin Production

[0241] (1) Acrylic resin

[0242] A mixture of 150g methyl methacrylate, 50g butyl methacrylate, and 1.2g tert-butyl peroxide (polymerization initiator) was added dropwise over 1.5 hours to 300g diethylene glycol diethyl ether, maintained at 100°C. After the addition was complete, the mixture was reacted at 100°C for 2 hours and then cooled to obtain a colorless and transparent polymer solution of methyl methacrylate (39.5% solids). The solvent was then thoroughly distilled off from the polymer solution. At this point, the average molecular weight (converted from polystyrene) of the polymerized methyl methacrylate (acrylic resin) was 30,000 (referred to as "acrylic resin" in the table).

[0243] (2) Vinyl chloride-vinyl acetate copolymer resin

[0244] After nitrogen replacement, 100 parts deionized water, 40 parts methanol, 32 parts vinyl chloride, 5 parts vinyl acetate, 0.2 parts glycidyl methacrylate, 3.55 parts hydroxypropyl acrylate, 0.1 parts hydroxypropyl methylcellulose (suspension agent), 0.026 parts di-2-ethylhexyl peroxide (polymerization initiator), and a specified amount of di-3,5,5-trimethylhexanol peroxide (polymerization initiator) were added to a high-pressure reactor equipped with a stirring device. Under a nitrogen atmosphere, the mixture was stirred and heated to 63°C. Immediately after reaching 63°C, 48 parts vinyl chloride were continuously added over 6 hours, followed by a mixture of 0.6 parts glycidyl methacrylate and 10.65 parts hydroxypropyl acrylate over 5.4 hours to initiate a copolymerization reaction. The residual pressure was released when the pressure inside the high-pressure reactor reached 0.3 MPa, and the mixture was cooled. The resin slurry was then removed, filtered, and dried to obtain a vinyl chloride-based copolymer resin. At this point, the amount of di-3,5,5-trimethylhexanol peroxide used as a polymerization initiator is changed, and the average molecular weight (converted from polystyrene) of the vinyl chloride-vinyl acetate copolymer resin is controlled to be 35,000 to 75,000 (referred to as "vinyl chloride-vinyl acetate copolymer 1 to 3" in the table).

[0245] Table 1

[0246]

[0247] 2. Preparation of non-aqueous ink compositions

[0248] Non-aqueous ink compositions of Examples A and Comparative Example A were prepared according to the proportions shown in the table below. Specifically, the components were dispersed using zirconium oxide beads in a paint stirrer to prepare the non-aqueous ink compositions. Units are parts by mass. It should be noted that the impurity concentrations of the organic solvents (a) and (b) used in Examples 1-69 were determined by gas chromatography before mixing.

[0249] [evaluate]

[0250] (Record dryness)

[0251] The drying properties of the non-aqueous ink compositions of Example A and Comparative Example A were evaluated. Specifically, the non-aqueous ink compositions of Example A and Comparative Example A were printed as solid images on a recording medium (IMAGin JT5829R: MACtac) in high-quality printing mode (1440x720dpi) using an inkjet printer (using the trade name VersaArt RE-640, manufactured by Roland DG Co., Ltd.), and the time until drying at 40°C was measured (in the table, it is denoted as "recording drying property").

[0252] Evaluation Criteria

[0253] Rating 5: Drys in less than 2 minutes.

[0254] Evaluation 4: Drying time is between 2 and 4 minutes.

[0255] Evaluation 3: Drying time is between 4 and 6 minutes.

[0256] Evaluation 2: Drying time is between 6 and 8 minutes.

[0257] Evaluation 1: Drys in 8 minutes or more.

[0258] (Component adaptability)

[0259] The component adaptability (printer head component adaptability) of the non-aqueous ink compositions of Example A and Comparative Example A was evaluated. Specifically, 0.2 g of the cured product obtained by drying the epoxy adhesive (two-component curing epoxy adhesive "1500", manufactured by CEMEDINE Co., Ltd.) used in the ink head component at 60°C for 1 day was impregnated in the ink compositions of Example A and Comparative Example A, and placed at 60°C for 1 week to conduct an impregnation test. The weight change of the cured product was measured (in the table, denoted as "component adaptability").

[0260] Evaluation Criteria

[0261] Evaluation 5: The weight change rate is less than 3%, and the epoxy adhesive material has not deteriorated.

[0262] Evaluation 4: The weight change rate is greater than 3% but less than 5%, and the epoxy adhesive material has not deteriorated.

[0263] Evaluation 3: The weight change rate is greater than 5% but less than 10%, and the epoxy adhesive material has not deteriorated.

[0264] Evaluation 2: The weight change rate is greater than 10% but less than 15%, and the epoxy adhesive material has not deteriorated.

[0265] Evaluation 1: Deterioration of materials with a weight change rate of more than 15% and / or the presence of epoxy adhesives.

[0266] (Post-processing)

[0267] The post-processing properties of the non-aqueous ink compositions of Example A and Comparative Example A were evaluated. Similar to the recording drying property evaluation described above, a 30cm x 30cm solid image of 100% magenta concentration was printed on a recording medium (a paste-coated polyvinyl chloride film (IMAGin JT5829R: manufactured by MACtac)) in high-quality printing mode (1440x720dpi) at a substrate surface temperature of 40°C. Immediately after printing, a laminate (LL Mitsuzawa Rami S: manufactured by Sakurai Co., Ltd.) was applied to the entire recording surface of the recording material and left for one day. The area of ​​peeling off the film was then confirmed. The results of the evaluation according to the following evaluation criteria are shown in the table below (in the table, it is denoted as "post-processing property").

[0268] Evaluation Criteria

[0269] Evaluation 5: Membrane peeling rate is 0%.

[0270] Evaluation 4: Membrane peeling exceeds 0% and is less than 3%.

[0271] Evaluation 3: The membrane peeling rate is above 3% and less than 5%.

[0272] Evaluation 2: The membrane peeling rate is above 5% and less than 10%.

[0273] Evaluation 1: The membrane peeling rate is over 10%.

[0274] (Maintain stability)

[0275] The storage stability of the non-aqueous ink compositions of Example A and Comparative Example A was evaluated. Specifically, the non-aqueous ink compositions were stored at 60°C for one month, and changes in viscosity and pigment volume average particle size (D50) before and after the test were observed. Storage stability was evaluated according to the following criteria. It should be noted that the viscosity of the ink was measured using a falling ball viscometer (Anton Paar AMVn) at 20°C, and the volume average particle size (D50) of the pigment was measured using a particle size distribution measuring device (MicrotracBEL NANOTRACWAVE particle size analyzer) at 25°C. It should be noted that in the following evaluation, the one with the larger rate of change between "viscosity" and "pigment volume average particle size" is considered the evaluation result of the non-aqueous ink composition.

[0276] Evaluation Criteria

[0277] Evaluation 5: The rate of change of both viscosity and the volume average particle size of the pigment is less than 3%.

[0278] Evaluation 4: Either the rate of change of viscosity and the volume average particle size of the pigment is greater than 3% and less than 5%.

[0279] Evaluation 3: Either the rate of change of viscosity and the volume average particle size of the pigment is greater than 5% and less than 8%.

[0280] Evaluation 2: Either the rate of change of viscosity and the volume average particle size of the pigment is greater than 8% and less than 10%.

[0281] Evaluation 1: Either the viscosity or the rate of change of the volume average particle size of the pigment is greater than 10%.

[0282] (Evaluation of bleeding properties)

[0283] Similar to the above-mentioned record drying evaluation, in a high-quality printing mode (1440x720dpi) and at a substrate surface temperature of 40°C, images with 6pt text of a different color in solid areas were printed on a recording medium (PVC film with paste (IMAGin JT5829R: manufactured by MACtac)). The resulting record was dried in an oven at 60°C for 5 minutes, and the bleeding of the record was observed visually.

[0284] Evaluation Criteria

[0285] Evaluation 4: No ink bleeding was observed, and the 6pt text was clear.

[0286] Evaluation 3: Slight ink bleeding was observed, but it did not impair the design.

[0287] Evaluation 2: Ink bleeding was observed, but 6pt text was still recognizable.

[0288] Evaluation 1: The ink bleeding was clearly observed, making it impossible to visually recognize the 6pt text.

[0289] Table 2

[0290]

[0291] Table 3

[0292]

[0293] Table 4

[0294]

[0295] As can be seen from the table above, the non-aqueous ink composition of Example A, containing organic solvents (a) and (b), exhibits high drying properties on the substrate surface and good post-processing properties of the resulting recorded material. Furthermore, the non-aqueous ink composition of Example A, containing organic solvents (a) and (b), also demonstrates good component adaptability, storage stability, and bleeding properties. Moreover, as shown in Examples 55-69, even when containing various colored pigments, the results are equivalent to those of Example 20, which contains carbon black.

[0296] Furthermore, for example, when comparing non-aqueous ink compositions containing 15.0% by mass of organic solvent (b) in the total amount of non-aqueous ink compositions, such as Example 20 (containing alkylamide solvent (b1)), Example 24 (containing alkylamide solvent (b1)), Example 30 (containing cyclic amide solvent (b2)), Example 32 (containing cyclic amide solvent (b2)), Example 33 (containing cyclic amide solvent (b2)), Example 34 (containing lactone solvent with 6 or more members (b3)), Example 35 (containing lactone solvent with 6 or more members (b3)), and Example 39 (containing lactone solvent with 6 or more members (b3)), the recording drying properties of Examples 20, 24, 30, 32, and 33 as organic solvent (b) are superior compared to Examples 34, 35, and 39.

[0297] Furthermore, when comparing Examples 17 to 21, which contain N,N-diethylformamide (alkylamide solvent (b1)) as organic solvent (b), Examples 20 and 21, which contain organic solvent (b) in a proportion of 17.0% by mass or less, exhibit particularly good component adaptability and post-processability.

[0298] It should be noted that, compared with Example 51 of the same composition ratio, the non-aqueous ink composition of Example 30 has a lower moisture content, higher drying performance on the substrate surface, and better preservation stability. Furthermore, compared with Example 52 of the same composition ratio, the non-aqueous ink composition of Example 30 has a lower concentration of impurities from organic solvents (a) and (b), higher drying performance on the substrate surface, and better post-processing properties of the resulting record.

[0299] Furthermore, compared to Example 45, which contains diethylene glycol dibutyl ether as an organic solvent (a), Example 20, which contains diethylene glycol methyl ethyl ether as an organic solvent (a), Example 44, which contains diethylene glycol diethyl ether as an organic solvent (a), and Example 46, which contains dipropylene glycol dimethyl ether as an organic solvent (a), exhibit particularly good record drying properties.

[0300] On the other hand, the non-aqueous ink composition of Example 70, which does not contain organic solvent (b) and 5-membered ring lactone solvent, exhibits poor drying properties and bleeding. Furthermore, the non-aqueous ink compositions of Examples 71-75, which contain 5-membered ring lactone solvent and 3-methoxy-N,N-dimethylpropionamide instead of organic solvent (b), show less bleeding but deteriorate post-processing properties. Additionally, the non-aqueous ink compositions of Examples 76-81, which do not contain organic solvent (a), exhibit deteriorated drying properties and component adaptability.

[0301] [Non-aqueous ink composition of the second embodiment]

[0302] 1. Resin Production

[0303] (1) Acrylic resin

[0304] A mixture of 150 g of methyl methacrylate, 50 g of butyl methacrylate, and a specified amount of tert-butyl peroxide (polymerization initiator) was added dropwise over 1.5 hours to 300 g of diethylene glycol diethyl ether, maintained at 100°C. After the addition was complete, the mixture was reacted at 100°C for 2 hours and then cooled to obtain a colorless and transparent polymer solution of methyl methacrylate (39.5% solids). The solvent was then thoroughly distilled off from the polymer solution. The amount of tert-butyl peroxide (2-ethylhexanoate) used as the polymerization initiator was varied to control the average absolute molecular weight of the polymerized methyl methacrylate (acrylic resin) (the mass of the polymerization initiator used is recorded in Table 1 below. Table 1 is labeled "Initiator Dosage"). It should be noted that the weight-average absolute molecular weight was determined using a GPC equipped with a TSKgel column (Tosoh Corporation) and a multi-angle light scattering detector (Wyatt Corporation, miniDawn TREOS). THF was used as the developing solvent.

[0305] (2) Vinyl chloride-vinyl acetate copolymer resin

[0306] After nitrogen replacement, 100 parts deionized water, 40 parts methanol, 32 parts vinyl chloride, 5 parts vinyl acetate, 0.2 parts glycidyl methacrylate, 3.55 parts hydroxypropyl acrylate, 0.1 parts hydroxypropyl methylcellulose (suspension agent), 0.026 parts di-2-ethylhexyl peroxide (polymerization initiator), and a specified amount of di-3,5,5-trimethylhexanol peroxide (polymerization initiator) were added to a high-pressure reactor equipped with a stirring device. Under a nitrogen atmosphere, the mixture was stirred and heated to 63°C. Immediately after reaching 63°C, 48 parts vinyl chloride were continuously added over 6 hours, followed by a mixture of 0.6 parts glycidyl methacrylate and 10.65 parts hydroxypropyl acrylate over 5.4 hours to initiate a copolymerization reaction. The residual pressure was released when the pressure inside the high-pressure reactor reached 0.3 MPa, and the mixture was cooled. The resin slurry was then removed, filtered, and dried to obtain a vinyl chloride-based copolymer resin. At this point, the amount of di-3,5,5-trimethylhexanol peroxide used as the polymerization initiator was changed to control the average absolute molecular weight of the vinyl chloride-vinyl acetate copolymer resin (the mass of the polymerization initiator used at this time is recorded in Table 1 below. Table 1 is labeled "Initiator Dosage"). It should be noted that the weight-average absolute molecular weight was determined using a GPC equipped with a TSKgel column (manufactured by Tosoh Corporation) and a multi-angle light scattering detector (manufactured by Wyatt Corporation, miniDawn TREOS). THF was used as the developing solvent.

[0307] (3) Cellulose resins

[0308] Use commercially available cellulose resins (EASTMAN CHEMICAL's CAP-482-0.5, CAB553-0.4, CAB551-0.01).

[0309] Table 5 shows the weight-average absolute molecular weight of each resin (acrylic resin, vinyl chloride-vinyl acetate copolymer resin, cellulose resin).

[0310] Table 5

[0311]

[0312] 2. Preparation of non-aqueous ink compositions

[0313] Non-aqueous ink compositions of Examples B and Comparative Example B were prepared according to the proportions shown in Table 6 below. Specifically, the components were dispersed using a paint stirrer and zirconium oxide beads to prepare the non-aqueous ink compositions. Units are parts by mass. It should be noted that the impurity concentrations of the organic solvent (b) and dialkyl glycol ether used in Examples 1-69 were determined by gas chromatography before mixing.

[0314] [evaluate]

[0315] (Record dryness)

[0316] The drying properties of the non-aqueous ink compositions of Example B and Comparative Example B were evaluated. Specifically, the non-aqueous ink compositions of Example B and Comparative Example B were printed as solid images on a recording medium (IMAGin JT5829R: MACtac) in high-quality printing mode (1440x720dpi) using an inkjet printer (using the trade name VersaArt RE-640, manufactured by Roland DG Co., Ltd.), and the time until drying at 40°C was measured (in the table, it is denoted as "recording drying property").

[0317] Evaluation Criteria

[0318] Rating 5: Drys in less than 2 minutes.

[0319] Evaluation 4: Drying time is between 2 and 4 minutes.

[0320] Evaluation 3: Drying time is between 4 and 6 minutes.

[0321] Evaluation 2: Drying time is between 6 and 8 minutes.

[0322] Evaluation 1: Drys in 8 minutes or more.

[0323] (Adhesive strength of raw material paste)

[0324] The adhesion properties of the non-aqueous ink compositions of Example B and Comparative Example B were evaluated. Specifically, similar to the recording drying performance evaluation described above, solid images printed on a recording medium (a paste-coated polyvinyl chloride film (3M Controltac Graphic Film IJ180: manufactured by 3M Corporation)) at a high-quality printing mode (1440x720 dpi) and a substrate surface temperature of 40°C were pasted onto an aluminum plate (adhesive). After being left for 1 hour, peel strength tests were performed using a TSNSILON RTG1250 tensile testing machine manufactured by A&D Corporation. A 50 N force sensor was used, and the test was conducted at a speed of 5 mm / s. The results of the evaluation according to the following evaluation criteria are shown in the table below (in the table, it is denoted as "raw material paste adhesion strength").

[0325] Rating 5: 5N / 20mm or higher

[0326] Rating 4: Above 4N / 20mm and below 5N / 20mm

[0327] Evaluation 3: 3N / 20mm or more but less than 4N / 20mm

[0328] Evaluation 2: Above 2N / 20mm and less than 3N / 20mm

[0329] Evaluation 1: Below 2N / 20mm

[0330] (Odor Test)

[0331] Similar to the above evaluation of drying properties, for records printed on a recording medium (a paste-coated polyvinyl chloride film (IMAGin JT5829R: manufactured by MACtac)) at a high-quality printing mode (1440x720dpi) and a substrate surface temperature of 40°C, six subjects were asked to smell the odor, and the highest score was taken as the evaluation of the non-aqueous ink composition (in the table, it is denoted as "odor").

[0332] Rating 5: No unpleasant odor.

[0333] Rating 4: It has a slight odor.

[0334] Evaluation 3: It smelled bad.

[0335] Rating 2: It has a slightly unpleasant odor.

[0336] Review 1: It has an unpleasant odor.

[0337] (Maintain stability)

[0338] The storage stability of the non-aqueous ink compositions of Example B and Comparative Example B was evaluated. Specifically, the non-aqueous ink compositions of Example B and Comparative Example B were stored at 60°C for one month, and the changes in viscosity and average particle size (D50) of the pigment before and after the test were observed. The storage stability was evaluated according to the following criteria. It should be noted that the viscosity of the ink was measured using a falling ball viscometer (Anton Paar AMVn) at 20°C, and the volume average particle size (D50) of the pigment was measured using a particle size distribution measuring device (MicrotracBEL NANOTRACWAVE particle size analyzer) at 25°C. It should be noted that in the following evaluation, the one with the larger rate of change between "viscosity" and "pigment volume average particle size" is used as the evaluation of the non-aqueous ink composition.

[0339] Evaluation Criteria

[0340] Evaluation 5: The rate of change of both viscosity and the volume average particle size of the pigment is less than 3%.

[0341] Evaluation 4: Either the rate of change of viscosity and the volume average particle size of the pigment is greater than 3% and less than 5%.

[0342] Evaluation 3: Either the rate of change of viscosity and the volume average particle size of the pigment is greater than 5% and less than 8%.

[0343] Evaluation 2: Either the rate of change of viscosity and the volume average particle size of the pigment is greater than 8% and less than 10%.

[0344] Evaluation 1: Either the viscosity or the rate of change of the volume average particle size of the pigment is greater than 10%.

[0345] (Stretchability)

[0346] The stretchability of the non-aqueous ink compositions of Example B and Comparative Example B was evaluated. Specifically, recordings were produced by printing (recording) on ​​a polyvinyl chloride substrate using an inkjet printer. For recordings immediately after printing on a recording medium (a paste-coated polyvinyl chloride film (IMAGin JT5829R: manufactured by MACtac)) in a high-quality printing mode (1440x720dpi) at a substrate surface temperature of 40°C, a solid print (recorded) portion of the recording at 100% magenta concentration was stretched to 200% at room temperature. For the decorative layers before and after stretching, the stretchability was measured using X-Rite eXact (manufactured by X-Rite) under conditions of a D65 light source and a 2° viewing angle. * a * b * In the L before and after the experiment * Let the difference be ΔL * , and the a before and after the experiment * Let the difference be Δa * b before and after the experiment * Let the difference be Δb * At that time, based on ΔE = [(ΔL)] * ) 2 +(Δa * ) 2 +(Δb * ) 2 ] 1 / 2 The calculated ΔE is then evaluated.

[0347] Evaluation Criteria

[0348] Evaluation 5: ΔE is less than 7.5.

[0349] Evaluation 4: ΔE is 7.5 or higher and less than 10.

[0350] Evaluation 3: ΔE is greater than 10 and less than 12.5.

[0351] Evaluation 2: ΔE is greater than 12.5 and less than 15.

[0352] Evaluation 1: ΔE is 15 or higher.

[0353] (Ejection stability)

[0354] The ejection stability of the non-aqueous ink compositions of Example B and Comparative Example B was evaluated. Specifically, as with the recording drying evaluation described above, fine lines were printed on a recording medium (a paste-coated polyvinyl chloride film (IMAGin JT5829R: manufactured by MACtac)) in a bidirectional high-speed printing mode (360x720 dpi) at a substrate surface temperature of 40°C, and the results were confirmed and evaluated visually and with a magnifying glass (5x) (referred to as "ejection stability" in the table).

[0355] Evaluation Criteria

[0356] Evaluation 4: Even with a magnifying glass, the fine lines can be reproduced correctly.

[0357] Evaluation 3: It cannot be determined by visual inspection, but if a magnifying glass is used for confirmation, the bend can be slightly identified.

[0358] Evaluation 2: The bend can be slightly detected by visual inspection.

[0359] Evaluation 1: Visual observation revealed obvious bending.

[0360] (Evaluation of bleeding properties)

[0361] Similar to the above evaluation of drying properties, images with 6pt text of a different color in solid areas were printed on a recording medium (PVC film with paste (IMAGin JT5829R: MACtac)) at a high-quality printing mode (1440x720dpi) and a substrate surface temperature of 40°C. The resulting printed material was dried in an oven at 60°C for 5 minutes, and the bleeding of the printed material was observed visually.

[0362] Evaluation Criteria

[0363] Evaluation 4: No ink bleeding was observed, and the 6pt text was clear.

[0364] Evaluation 3: Slight ink bleeding was observed, but it did not impair the design.

[0365] Evaluation 2: Ink bleeding was observed, but 6pt text was still recognizable.

[0366] Evaluation 1: The ink bleeding was clearly observed, making it impossible to visually recognize the 6pt text.

[0367] Table 6

[0368]

[0369] Table 7

[0370]

[0371] As shown in Tables 6 and 7, if the non-aqueous ink composition contains an organic solvent (b) and a resin with a weight-average absolute molecular weight of 15,000 or more and 80,000 or less, even when using a resin substrate with an adhesive layer on one side, and recording (printing) the non-aqueous ink composition on the substrate surface without the adhesive layer, the degradation of the adhesive layer's adhesion (the adhesion of the recorded object to the substrate) can be suppressed, and even when the recorded object is stretched, the whitening of the decorative layer can be effectively suppressed. The non-aqueous ink composition containing an organic solvent (b) and a resin with a weight-average absolute molecular weight of 15,000 or more and 80,000 or less also exhibits good recording drying properties, odor, storage stability, ejection stability, and bleeding properties. Furthermore, as shown in Examples 42 to 56, even when containing various colored pigments, the results are equivalent to those in Example 3 containing carbon black.

[0372] Furthermore, for example, when comparing Examples 3, 5, and 6 (containing alkylamide solvent (b1)), Examples 7, 10, and 11 (containing cyclic amide solvent (b2)), and Examples 12, 13, and 16 (containing lactone solvent (b3) with a 6-membered ring or more) in the total amount of non-aqueous ink compositions, the raw material paste adhesive strength of Examples 3, 5, 6, 7, 10, and 11, which contain alkylamide solvent (b1) or cyclic amide solvent (b2) as organic solvent (b), is superior compared to Examples 12, 13, and 16.

[0373] Furthermore, when comparing Examples 1 to 4, which contain N,N-diethylformamide (alkylamide solvent (b1)) as organic solvent (b), the raw material pastes of Examples 3 and 4, which contain organic solvent (b) in a proportion of 15.0% by mass or less, exhibit excellent adhesive strength.

[0374] Furthermore, when comparing common examples 3, 17 to 19, except for those containing resins with different weight-average absolute molecular weights, examples 3, 17 and 18, which have a weight-average absolute molecular weight of 25,000 or more, exhibit excellent tensile properties. Among them, examples 3 and 17, which have a weight-average absolute molecular weight of 32,500 or more, exhibit particularly excellent tensile properties.

[0375] It should be noted that, compared with Example 37 of the same composition ratio, the non-aqueous ink composition of Example 3 has a lower moisture content and better storage stability and drying properties. In addition, compared with Example 38 of the same composition ratio, the non-aqueous ink composition of Example 3 has a lower concentration of impurities from organic solvent (b) and glycol dialkyl ether, excellent raw material paste adhesion strength, and good drying properties and odor.

[0376] On the other hand, Examples 61, 62, and 64, which contain resins with a weight-average absolute molecular weight exceeding 80,000, exhibit poor ejection stability. Furthermore, Examples 63 and 65, which contain resins with a weight-average absolute molecular weight less than 15,000, show reduced tensile strength. Additionally, the non-aqueous ink compositions of Examples 66 to 70, which contain a 5-membered ring lactone solvent and 3-methoxy-N,N-dimethylpropionamide instead of organic solvent (b), show deteriorated raw material paste adhesive strength.

Claims

1. A non-aqueous ink composition containing an organic solvent, The organic solvent contains the following organic solvent (a) and the following organic solvent (b). Organic solvent (a): Diol dialkyl ether, Organic solvent (b): selected from at least one of alkyl amide solvents (b1) and cyclic amide solvents (b2). The alkylamide solvent (b1) is represented by the following general formula (2), In formula (2), R4 is hydrogen or an alkyl group with 1 or more but less than 4 carbon atoms, and R5 represents an alkyl group with 2 carbon atoms. The cyclic amide solvent (b2) is represented by the following general formula (3). In formula (3), R6 is an alkylene group with 5 carbon atoms, and R7 represents hydrogen or an alkyl or unsaturated hydrocarbon group with 1 or more but less than 2 carbon atoms.

2. The non-aqueous ink composition according to claim 1, wherein, The content of the organic solvent (b) is in the range of 3.0% by mass or more and 30.0% by mass or less in the total amount of the non-aqueous ink composition.

3. The non-aqueous ink composition according to claim 1 or 2, wherein, The organic solvent (a) is a dialkyl glycol ether represented by the following formula (1). In formula (1), R1 and R3 are alkyl groups, R2 represents ethylene or propylene, and n represents an integer from 2 to 4.

4. The non-aqueous ink composition according to claim 3, wherein, The total number of carbon atoms contained in R1 and R3 in the formula (1) is more than 2 and less than 6.

5. The non-aqueous ink composition according to claim 4, wherein, In organic solvent (a), In formula (1), R1 is methyl or ethyl, and R3 in formula (1) is ethyl. and / or In formula (1), R1 and R3 are methyl and R2 is propylene.

6. The non-aqueous ink composition according to claim 1 or 2, wherein, The content of impurities from the organic solvent (a) is less than 0.5% by mass in the total amount of organic solvent (a). The content of impurities from the organic solvent (b) is less than 0.5% by mass in the total amount of organic solvent (b).

7. A non-aqueous ink composition comprising an organic solvent and a resin, The organic solvent contains the following organic solvent (b). The weight-average absolute molecular weight of the resin is above 15,000 and below 80,000. Organic solvent (b): selected from at least one of alkyl amide solvents (b1) and cyclic amide solvents (b2). The alkylamide solvent (b1) is represented by the following general formula (2), In formula (2), R4 is hydrogen or an alkyl group with 1 or more but less than 4 carbon atoms, and R5 represents an alkyl group with 2 carbon atoms. The cyclic amide solvent (b2) is represented by the following general formula (3). In formula (3), R6 is an alkylene group with 5 carbon atoms, and R7 represents hydrogen or an alkyl or unsaturated hydrocarbon group with 1 or more but less than 2 carbon atoms.

8. The non-aqueous ink composition according to claim 7, wherein, The resin comprises at least one selected from acrylic resins, vinyl chloride-vinyl acetate copolymer resins, and cellulose resins.

9. The non-aqueous ink composition according to claim 7 or 8, wherein, The content of impurities from the organic solvent (b) is less than 0.5% by mass in the total amount of organic solvent (b).

10. The non-aqueous ink composition according to claim 1 or 7, wherein, The organic solvent (b) is an alkylamide solvent (b1).

11. The non-aqueous ink composition according to claim 10, wherein, The alkylamide solvent (b1) contains at least one selected from N,N-diethylformamide, N,N-diethylpropionamide and N,N-diethylacetamide.

12. The non-aqueous ink composition according to claim 1 or 7, wherein, The organic solvent (b) is a cyclic amide solvent (b2).

13. The non-aqueous ink composition according to claim 12, wherein, The cyclic amide solvent (b2) contains at least one selected from ε-caprolactam, N-methylcaprolactam, and N-vinylcaprolactam.

14. The non-aqueous ink composition according to claim 1 or 7, wherein, The moisture content is less than 1.0% by mass in the total amount of the non-aqueous ink composition.

15. The non-aqueous ink composition according to claim 1 or 7, used on a resin substrate.

16. A recording method, wherein, The non-aqueous ink composition of claim 1 or 7 is sprayed onto the surface of a substrate by inkjet printing.

17. A method for manufacturing a recording, wherein, The non-aqueous ink composition of claim 1 or 7 is sprayed onto the surface of a substrate by inkjet printing.

Images