JP7848619B2 - Resin aqueous dispersions and aqueous inks - Google Patents

Description

This invention relates to an aqueous resin dispersion and an aqueous ink.

Inkjet recording is widely used because it allows for the recording of a wide variety of high-quality images on a wide variety of recording media by ejecting ink in droplet form from numerous nozzles on an inkjet head. Inkjet printing is being actively researched due to advancements in pigment dispersion technology, which offers superior weather resistance. Printed materials using pigment-containing inks exhibit high color vibrancy because the pigment components tend to localize easily on the surface of the recording medium. The pigment remains on the recording medium surface due to evaporation and penetration of vehicle components during the ink's adhesion process and after adhesion. However, because pigment inks, being colorants, tend to remain on the recording medium surface, the adhesion and blocking resistance of the ink film are particularly important. To improve these properties recorded with pigment inks, the addition of binder resins to the ink is being considered (Patent Documents 1 and 2).

Japanese Patent Publication No. 2017-218521 Patent No. 3897268

As non-permeable recording media, there are polar recording media with many polar groups, such as polyethylene terephthalate (PET) and nylon, and low-polarity recording media with few polar groups, such as polypropylene (OPP). For both types of recording media, the ink coatings that provide excellent properties such as adhesion are still not sufficient.

The object of the present invention is to provide a resin aqueous dispersion with excellent adhesion to non-permeable recording media, and to provide an aqueous ink containing the above resin aqueous dispersion that has excellent inkjet suitability, blocking resistance, and boil/retort resistance.

The inventors have arrived at the present invention as a result of diligent research. Specifically, the present invention is an aqueous resin dispersion (Q) containing a resin (P) having a constituent unit represented by general formula (1); and an aqueous ink (L) containing the aqueous resin dispersion.
[In general formula (1), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms, R2 is an aliphatic alkylene group having 1 to 6 carbon atoms, X is an amide group, and Y is an ester group or a urethane group.]

The dried film obtained from the aqueous resin dispersion (Q) of the present invention exhibits excellent adhesion to both polar substrates such as PET and nylon, and low-polarity substrates such as OPP. Furthermore, the aqueous ink (L) of the present invention, containing the above-mentioned aqueous resin dispersion (Q), exhibits excellent blocking resistance and boil/retort resistance. When used as an inkjet ink, it is less prone to head nozzle clogging, enabling stable printing, thus demonstrating excellent inkjet suitability.

The aqueous resin dispersion of the present invention contains a resin (P) having a constituent unit represented by general formula (1).
[In general formula (1), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms, R2 is an aliphatic alkylene group having 1 to 6 carbon atoms, X is an amide group, and Y is an ester group or a urethane group.]
In this specification, the term "aliphatic alkylene group" includes both linear aliphatic alkylene groups and branched aliphatic alkylene groups.

Examples of resin (P) include resin (p1) obtained by polycondensation of a carboxylic acid component (a) and an amino alcohol (b), and/or resin (p2) obtained by polycondensation of an amine component (c) and a hydroxy acid (d). Furthermore, resin (P) may be a polyurethane-modified resin containing a urethane group.

Examples of carboxylic acid component (a) include dicarboxylic acids (a1) and polycarboxylic acids with a valentity of three or more (a2). These may be used individually or in combination of two or more. The number of carbon atoms in the carboxylic acid components shown below includes the number of carbon atoms in the carboxyl group.
Examples of dicarboxylic acids (a1) include aromatic dicarboxylic acids having 8 to 36 carbon atoms (phthalic acid, isophthalic acid, and naphthalenedicarboxylic acid, etc.), aliphatic dicarboxylic acids having 2 to 50 carbon atoms (oxalic acid, malonic acid, succinic acid, adipic acid, azelaic acid (nonannic acid, reparginic acid), sebacic acid, dodecanediic acid, butyloctanedioic acid, eicosanedioic acid, eicosadienediic acid, isoeicosanedioic acid, docosanedioic acid, isodocosanedioic acid, isodocosadienediic acid, etc.), alicyclic dicarboxylic acids having 6 to 44 carbon atoms [dimeric acid (dimerized linoleic acid), etc.], alkenedicarboxylic acids having 4 to 36 carbon atoms (alkenyl succinic acid such as dodecenyl succinic acid, maleic acid, fumaric acid, citraconic acid, and mesaconic acid, etc.), and ester-forming derivatives thereof. Here, ester-forming derivatives refer to carboxylic acid anhydrides, alkyl (methyl, ethyl, butyl, stearyl, etc., having 1 to 24 carbon atoms, preferably having 1 to 4 carbon atoms) esters, and partially alkyl esters.
When the resin (P) is a resin (p1) obtained by polycondensation of a carboxylic acid component (a) and an amino alcohol (b), the carboxylic acid component (a) is preferably a dicarboxylic acid (a1). More preferably, it is a dicarboxylic acid (a1) having 13 to 66 carbon atoms, and even more preferably a dimer acid having 36 to 44 carbon atoms. When a dimer acid having 36 to 44 carbon atoms is used, the number of carbon atoms in R1 will be 34 to 42.

Examples of polycarboxylic acids with a valency of 3 or more (a2) include aromatic polycarboxylic acids with 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid), aliphatic (including alicyclic) tricarboxylic acids with 6 to 66 carbon atoms (such as trimer acid, hexanetricarboxylic acid and decanetricarboxylic acid), and ester-forming derivatives thereof.
When the resin (P) is a resin (p2) obtained by polycondensation of a carboxylic acid component (a), an amine component (c), and a hydroxy acid (d), the carboxylic acid component (a) is preferably a trivalent or higher polycarboxylic acid (a2), and is preferably trimellitic anhydride.

Of these carboxylic acid components, aliphatic dicarboxylic acids are preferred from the viewpoint of adhesion to OPP substrates, boil/retort resistance, and inkjet suitability, with a preferred number of carbon atoms of 2 to 50, more preferably 20 to 50, and even more preferably 36 to 44.

Furthermore, monocarboxylic acid components may be included as necessary carboxylic acid components to obtain the resin (P). Examples of monocarboxylic acids include aromatic monocarboxylic acids having 7 to 37 carbon atoms (benzoic acid, toluic acid, 4-ethylbenzoic acid, 4-propylbenzoic acid, etc.) and aliphatic (including alicyclic) monocarboxylic acids having 2 to 50 carbon atoms (acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, and behenic acid, etc.).
When the carboxylic acid component for obtaining resin (P) contains a monocarboxylic acid component, a resin (P) in which Y of general formula (1) is an ester group can be obtained by first obtaining a structure with a terminal hydroxyl group by reacting dicarboxylic acid (a) with amino alcohol (b), and then reacting with the monocarboxylic acid.

From the viewpoint of abrasion resistance, the dicarboxylic acid (a1) in the carboxylic acid component (a) of resin (P) is preferably 80 to 100 mol%, and more preferably 100 mol%.

In one embodiment, the carboxylic acid component (a) can be derived from biomass. Biomass-derived raw materials refer to raw materials derived from plants and microorganisms.

Examples of carboxylic acid components derived from biomass include malonic acid, succinic acid, itaconic acid, adipic acid, azelaic acid, sebacic acid, and dimer acid.

Examples of amino alcohols (b) include primary amino alcohols (b1) and secondary amino alcohols (b2). These may be used individually or in combination of two or more types.
Examples of primary amino alcohols (b1) include ethanolamine, 1-amino-2-propanol, 2-amino-1-propanol, 3-amino-1-propanol, 1-amino-2-butanol, 2-amino-1-butanol, 4-amino-1-butanol, 5-amino-1-pentanol, and 6-amino-1-hexanol. Examples of secondary amino alcohols (b2) include N-methylethanolamine, 1-(ethylamino)-2-propanol, and 2-(propylamino)ethanol. From the viewpoint of OPP adhesion, amino alcohols having 1 to 6 carbon atoms are preferred, more preferably secondary amino alcohols having 1 to 6 carbon atoms, and even more preferably N-methylethanolamine.

The carbon number of a secondary amino alcohol includes the carbon number of the alkyl group bonded to the nitrogen atom. When amino alcohol (b) is a secondary amino alcohol (b2), it is preferable that the carbon number of the main chain of amino alcohol (b) is 1 to 6. If amino alcohol (b) is a secondary amino alcohol (b2), and the carbon number of the main chain of amino alcohol (b) is 1 to 6, the sum of the carbon number of the main chain of amino alcohol (b) and the carbon number of the alkyl group bonded to the nitrogen atom, i.e., the carbon number of the secondary amino alcohol (b2), may be 7 or more.

When resin (P) is a resin (p1) obtained by polycondensation of a carboxylic acid component (a) and an amino alcohol (b), the overall structure of resin (p1) is as shown in the general formula (2) below.
[In general formula (2), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms derived from the carboxylic acid component (a), R2 is an aliphatic alkylene group having 1 to 6 carbon atoms derived from the main chain of the amino alcohol (b), and R3 is a hydrogen atom or alkyl group derived from the amino group of the amino alcohol (b).]

In this case, the resin (p1) can be said to be a resin consisting of repeating constituent units represented by the following general formula (3).
[In general formula (3), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms, R2 is an aliphatic alkylene group having 1 to 6 carbon atoms, and R3 is a hydrogen atom or an alkyl group.]

When the resin (p1) is a resin consisting of repeating constituent units represented by general formula (3), the average number of repeating constituent units is preferably 1 to 100. More preferably, the average number of repeating units is 2 to 50, and particularly preferably 5 to 20.
Furthermore, the number-average molecular weight of the resin (p1) is preferably 350 to 50,000. More preferably 500 to 25,000, and particularly preferably 1,000 to 10,000.
The number-average molecular weight used herein can be measured by gel permeation chromatography under the following conditions.
Device: "HLC-802A" [Manufactured by Tosoh Corporation]
Column: "TSK gel GMH6" [manufactured by Tosoh Corporation] (2 pieces) Measurement temperature: 40℃
Sample solution: 0.25% by weight tetrahydrofuran solution. Solution injection volume: 100 μl
Detection device: Refractive index detector Reference material: Standard polystyrene (TSK standard polystyrene)
12 samples (molecular weights: 500, 1,050, 2,800, 5,970, 9,100, 18,100, 37,900, 96,400, 190,000, 355,000, 1,090,000, 2,890,000) [Manufactured by Tosoh Corporation]

The amide group content of the resin (p1) is preferably 0.1 to 2.8 mmol/kg, more preferably 0.3 to 2.0 mmol/kg, and even more preferably 0.5 to 1.8 mmol/kg. A higher proportion of amide groups improves blocking resistance and boil resistance, and enhances adhesion to nylon.

The ester group content of the resin (p1) is preferably 0.1 to 2.8 mmol/kg, more preferably 0.3 to 2.0 mmol/kg, and even more preferably 0.5 to 1.8 mmol/kg. A higher proportion of ester groups improves adhesion to PET.

Examples of amine components (c) include diamines (c1) and polyamines with a valentity of three or more (c2). These may be used individually or in combination of two or more.
Examples of diamines (c1) include diamines having 2 to 10 carbon atoms (e.g., ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, toluenediamine, and piperazine), and dibasic acid amine derivatives and dimer amines of aliphatic (including alicyclic) diamines having 11 to 44 carbon atoms.
Examples of polyamines (c2) include polyalkylene polyamines having 2 to 10 carbon atoms, such as diethylenetriamine, triethylenetetramine, and tetraethylenepentamine, and trimertriamines of aliphatic (including alicyclic) triamines having 6 to 64 carbon atoms. Of these amine components, those with 11 to 64 carbon atoms are preferred from the viewpoint of adhesion to OPP substrates, resistance to boiling and retorting, and suitability for inkjet printing, more preferably 18 to 64 carbon atoms, and even more preferably 36 to 44 carbon atoms. Even more preferably, dimeramines with 36 to 44 carbon atoms are used.
From the viewpoint of OPP adhesion, the diamine (c1) in the amine component (c) of the resin (P) is preferably 80 to 100 mol%.

When amine component (c) is a secondary amine, the carbon number includes the carbon number of the alkyl group bonded to the nitrogen atom. Furthermore, when amine component (c) is a secondary amine, it is preferable that the carbon number of the main chain of amine component (c) is between 11 and 64. If amine component (c) is a secondary amine, and the carbon number of the main chain of amine component (c) is between 11 and 64, the sum of the carbon number of the main chain of amine component (c) and the carbon number of the alkyl group bonded to the nitrogen atom, i.e., the carbon number of amine component (c), may be 65 or more.

In one embodiment, the amine component (c) can be derived from biomass. Biomass-derived raw materials refer to raw materials derived from plants and microorganisms.

Examples of amine components from biomass-derived raw materials include 1,10-decanediamine and dimeramine.

Examples of hydroxy acids (d) include aliphatic hydroxy acids and aromatic hydroxy acids. Examples of aliphatic hydroxy acids include glycolic acid, hydroxypropionic acid, hydroxybutanoic acid, hydroxypentanoic acid, hydroxyhexanoic acid, hydroxyheptanoic acid, hydroxynonanoic acid, hydroxydecanoic acid, hydroxyundecanoic acid, hydroxydodecanoic acid, hydroxytridecanoic acid, hydroxytetradecanoic acid, hydroxypentadecanoic acid, hydroxyhexadecanoic acid, hydroxyheptadecanoic acid, hydroxyoctadecanoic acid, hydroxynonadecanoic acid, hydroxyicosanoic acid, hydroxydocosanoic acid, hydroxytetradocosanoic acid, hydroxyhexadocosanoic acid, hydroxyoctadocosanoic acid, lactic acid, tartaric acid, glyceric acid, hydroxybutyric acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, γ-hydroxybutyric acid, malic acid, tartaric acid, citramalic acid, citric acid, isocitric acid, leucic acid, mevalonic acid, pantoic acid, ricinoleic acid, ricineradicic acid, cerebronic acid, quinic acid, shikimic acid, and others.
Examples of aromatic hydroxy acids include monohydroxybenzoic acid derivatives such as salicylic acid, creosote acids (homosalicylic acid, hydroxy(methyl)benzoic acid), vanillic acid, and syringic acid; dihydroxybenzoic acid derivatives such as pyrocateucoic acid, resorsilicic acid, protocatechuic acid, gentisic acid, and orceric acid; trihydroxybenzoic acid derivatives such as gallic acid; phenylacetic acid derivatives such as mandelic acid, benzyl acid, atrolactinic acid, cinnamic acid, and hydrocinnamic acid derivatives such as melilotic acid, floretic acid, coumaric acid, umberic acid, caffeic acid, ferulic acid, and sinapic acid. These may be used individually or in combination of two or more. From the viewpoint of OPP adhesion, aliphatic hydroxy acids are preferred, more preferably aliphatic hydroxy acids having 1 to 6 carbon atoms, even more preferably aliphatic hydroxy acids having 2 to 6 carbon atoms, and most preferably aliphatic hydroxy acids having 2 to 4 carbon atoms. Lactic acid or 6-hydroxyhexanoic acid are particularly preferred.
The number of carbon atoms in the hydroxy acids shown above includes the number of carbon atoms in the carboxyl group.

In one embodiment, the hydroxy acid (d) can be derived from biomass.

Examples of hydroxy acids derived from biomass include glycolic acid, lactic acid, hydroxybutyric acid, and ricinoleic acid.

When resin (P) is a resin (p2) obtained by polycondensation of a carboxylic acid component (a), an amine component (c), and a hydroxy acid (d), the overall structure of resin (p2) is as shown in the general formula (4) below.
[In general formula (4), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms derived from the main chain of amine component (c), R2 is an aliphatic alkylene group having 1 to 6 carbon atoms derived from the hydroxy acid (d), R3 is a hydrogen atom or alkyl group derived from the amino group of amine component (c), and R4 is a group derived from carboxylic acid component (a).]

In this case, the resin (p2) can be said to be a resin consisting of repeating constituent units represented by the following general formula (5).
[In general formula (5), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms, R2 is an aliphatic alkylene group having 1 to 6 carbon atoms, R3 is a hydrogen atom or an alkyl group, and R4 is a group derived from carboxylic acid component (a).]

When resin (P) is a resin (p2) obtained by polycondensation of carboxylic acid component (a), amine component (c), and hydroxy acid (d), resin (p2) can be obtained by reacting amine component (c) and hydroxy acid (d) first, and then reacting with carboxylic acid component (a). In this procedure, R2 in general formulas (1), (4), and (5) becomes an aliphatic alkylene group derived from hydroxy acid (d). Furthermore, R3 in general formulas (4) and (5) becomes a hydrogen atom or alkyl group derived from the amino group of amine component (c), and R4 becomes a group derived from carboxylic acid component (a).

When the resin (p2) is a resin consisting of repeating constituent units represented by general formula (5), the average number of repeating constituent units is preferably 1 to 100, more preferably 2 to 50, and even more preferably 5 to 20.
Furthermore, the number-average molecular weight of the resin (p2) is preferably 400 to 50,000, more preferably 500 to 25,000, and even more preferably 1,000 to 10,000.

The amide group content of the resin (p2) is preferably 0.1 to 2.8 mmol/kg, more preferably 0.3 to 2.0 mmol/kg, and even more preferably 0.5 to 1.8 mmol/kg. A higher proportion of amide groups improves blocking resistance and boil resistance, and enhances adhesion to nylon.

The ester group content of the resin (p2) is preferably 0.1 to 2.8 mmol/kg, more preferably 0.3 to 2.0 mmol/kg, and even more preferably 0.5 to 1.8 mmol/kg. A higher proportion of ester groups improves adhesion to PET.

In the present invention, for obtaining the resin (P), a carboxylic acid component (a) or an amine component (c) having 13 to 66 carbon atoms can be used as an essential component from the viewpoint of adhesion to OPP film and resistance to boiling and retorting. The number of carbon atoms in the carboxylic acid component (a) is preferably 13 to 44, more preferably 13 to 36, and particularly preferably 20 to 36.
The number of carbon atoms in the amine component (c) is preferably 11 to 44, more preferably 11 to 36, and particularly preferably 18 to 36.

In this invention, the amino alcohol (b) or hydroxy acid (d) of the resin (P) contains an amino alcohol (b) or hydroxy acid (d) having 1 to 7 carbon atoms as an essential component from the viewpoint of blocking resistance and boil/retort resistance. The number of carbon atoms in the amino alcohol (b) is preferably 2 to 6, more preferably 2 to 4. The number of carbon atoms in the hydroxy acid (d) is preferably 3 to 7, more preferably 3 to 5.

The acid value of the resin (P) is preferably 10 to 50 mg KOH/g, preferably 15 to 30 mg KOH/g, and preferably 15 to 25 mg KOH/g. A higher acid value can reduce the volume-average particle size of the resin particles. The acid value can be measured by the method described in JIS K1557.

In the case where the resin (P) is a polyurethane-modified resin containing urethane groups, the constituent components include the carboxylic acid component (a), amino alcohol (b), amine component (c), and hydroxy acid (d) mentioned above, as well as polyisocyanate (e), active hydrogen group-containing compound (f), chain extender (g), and the like.

When resin (P) is a polyurethane-modified resin containing urethane groups, examples of polyurethane-modified resins include a resin (p3) in which the terminal hydroxyl groups of the resin, formed by the polycondensation of carboxylic acid component (a) and amino alcohol (b), react with polyisocyanate, resulting in a structure where Y in general formula (1) is a urethane group. Another example is a resin (p4) in which the terminal hydroxyl groups of the resin, formed by the polycondensation of amine component (c) and hydroxy acid (d), react with polyisocyanate, resulting in a structure where Y in general formula (1) is a urethane group.

Examples of polyisocyanates (e) include aromatic polyisocyanates having 8 to 22 carbon atoms (including the carbon atoms in the isocyanate groups, the same applies hereinafter) having two or more isocyanate groups, aliphatic polyisocyanates having 4 to 20 carbon atoms, alicyclic polyisocyanates having 6 to 17 carbon atoms, aromatic aliphatic polyisocyanates having 10 to 17 carbon atoms, and derivatives of these polyisocyanates (e.g., isocyanurates).
The polyisocyanate component may be used alone, or two or more may be used in combination.

Examples of aromatic polyisocyanates having 8 to 22 carbon atoms include 1,3- or 1,4-phenylenediisocyanate, 2,4- or 2,6-tolylenediisocyanate (TDI), 4,4'- or 2,4'-diphenylmethanediisocyanate (MDI), 1,5-naphthylenediisocyanate, 4,4',4''-triphenylmethanetriisocyanate, m- or p-isocyanatophenylsulfonyl isocyanate, crude MDI, and the like.

Examples of aliphatic polyisocyanates having 4 to 20 carbon atoms include ethylene diisocyanate, tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, and 2-isocyanatoethyl-2,6-diisocyanatohexanoate.

Examples of alicyclic polyisocyanates having 6 to 17 carbon atoms include isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis(2-isocyanatoethyl)-4-cyclohexene-1,2-dicarboxylate, and 2,5- or 2,6-norbornane diisocyanate.

Examples of aromatic aliphatic polyisocyanates having 10 to 17 carbon atoms include m- or p-xylylene diisocyanate (XDI) and α,α,α',α'-tetramethylxylylene diisocyanate (TMXDI).

From the viewpoint of the volume-average particle size and mechanical strength of the resin (P), aromatic polyisocyanates with 8 to 22 carbon atoms and alicyclic polyisocyanates with 6 to 17 carbon atoms are preferred as the polyisocyanate component, and 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane-4,4-diisocyanate are more preferred.

Examples of active hydrogen group-containing compounds (f) include high molecular weight diols (f1), diols having carboxyl groups and/or carboxylate anion groups (f2), and low molecular weight polyols (f3).

The polymeric diol (f1) is not particularly limited, but examples include polyether polyols, polycarbonate polyols, polyester polyols, and polyolefin polyols.

The polyether polyol is not particularly limited, but examples include aliphatic polyether diols and aromatic polyether diols.

The aliphatic polyether diol is not particularly limited, but examples include adducts of alkylene oxides (hereinafter abbreviated as AO) with 2 to 12 carbon atoms to aliphatic polyhydric alcohols with 2 to 20 carbon atoms. Specifically, examples include polyoxyalkylene glycols (polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, and polyoxyethylene/propylene glycol, etc.).

Commercially available aliphatic polyetherdiols include PTMG1000 [poly(oxytetramethylene) glycol with Mn=1000, manufactured by Mitsubishi Chemical Corporation], PTMG2000 [poly(oxytetramethylene) glycol with Mn=2000, manufactured by Mitsubishi Chemical Corporation], PTMG3000 [poly(oxytetramethylene) glycol with Mn=3000, manufactured by Mitsubishi Chemical Corporation], BioPTMG1000 [biomass-derived poly(oxytetramethylene) glycol with Mn=1000, manufactured by Mitsubishi Chemical Corporation], BioPTMG2000 [biomass-derived poly(oxytetramethylene) glycol with Mn=2000, manufactured by Mitsubishi Chemical Corporation], and BioPTMG3000 [biomass-derived poly(oxytetramethylene) glycol with Mn=3000]. Examples include poly(oxytetramethylene) glycol (manufactured by Mitsubishi Chemical Corporation), PTGL2000 (modified poly(oxytetramethylene) glycol with Mn=2000, manufactured by Hodogaya Chemical Co., Ltd.), PTGL3000 (modified poly(oxytetramethylene) glycol with Mn=3000, manufactured by Hodogaya Chemical Co., Ltd.), PTG1000SN(P) (biomass-derived poly(oxytetramethylene) glycol with Mn=1000, manufactured by Hodogaya Chemical Co., Ltd.), PTG2000SN(P) (biomass-derived poly(oxytetramethylene) glycol with Mn=2000, manufactured by Hodogaya Chemical Co., Ltd.), and Sannix PP-2000 (polyoxypropylene glycol with Mn=2000, manufactured by Sanyo Chemical Industries, Ltd.). In this embodiment, "Mn" refers to the number-average molecular weight.

Aromatic polyether diols are not particularly limited, but examples include diols having a bisphenol skeleton, such as ethylene oxide (hereinafter abbreviated as EO) adducts of bisphenol A (e.g., bisphenol A EO 2-mol adduct, bisphenol A EO 4-mol adduct, bisphenol A EO 6-mol adduct, bisphenol A EO 8-mol adduct, bisphenol A EO 10-mol adduct, and bisphenol A EO 20-mol adduct) and propylene oxide (hereinafter abbreviated as PO) adducts of bisphenol A (e.g., bisphenol A PO 2-mol adduct, bisphenol A PO 3-mol adduct, and bisphenol A PO 5-mol adduct), as well as EO or PO adducts of resorcinol.

The polycarbonate polyol is not particularly limited, but examples include polycarbonate polyols produced by condensing one or more polyhydric alcohols having 2 to 20 carbon atoms with a low molecular weight carbonate compound (e.g., dialkyl carbonates with alkyl groups having 1 to 6 carbon atoms, alkylene carbonates having alkylene groups with 2 to 6 carbon atoms, and diaryl carbonates having aryl groups with 6 to 9 carbon atoms) while undergoing a de-alcoholization reaction.

The polycarbonate polyols are not particularly limited, but examples include polyhexamethylene carbonate diol, polypentamethylene carbonate diol, 3-methyl-5-pentane carbonate diol, polytetramethylene carbonate diol, and poly(tetramethylene/hexamethylene) carbonate diol (such as a diol obtained by condensing 1,4-butanediol and 1,6-hexanediol with a dialkyl carbonate while de-alcoholizing).

There are no particular restrictions on commercially available polycarbonate polyols, but for example, Nippon Laurel 980R [Polycarbonate polyol with Mn=2000 using 1,6-hexanediol, manufactured by Nippon Polyurethane Industries Co., Ltd.], Duranol T6002 [Polycarbonate polyol with Mn=2000 using 1,6-hexanediol, manufactured by Asahi Kasei Chemicals Corporation], ETERNACOLL UH-300 [Polycarbonate polyol with Mn=3000 using 1,6-hexanediol, manufactured by Ube Industries, Ltd.], ETERNACOLL UH-200 [Polycarbonate polyol with Mn=2000 using 1,6-hexanediol, manufactured by Ube Industries, Ltd.], ETERNACOLL UM-90 (1/3) [Mn=900 polycarbonate polyol using 1,4-cyclohexanedimethanol/1,6-hexanediol = 1/3 (molar ratio), manufactured by Ube Industries, Ltd.], Duranol G4672 [Mn=2000 polycarbonate polyol using 1,4-butanediol/1,6-hexanediol = 70/30 (molar ratio), manufactured by Asahi Kasei Chemicals Corporation], Duranol T5652 [Polycarbonate polyol with Mn=2000 using 1,5-pentanediol/1,6-hexanediol = 50/50 (molar ratio), manufactured by Asahi Kasei Chemicals Corporation], T4672 [Polycarbonate polyol with Mn=2000 using 1,4-butanediol/1,6-hexanediol, manufactured by Asahi Kasei Chemicals Corporation], Kuraray Polyol C-2090 [Polycarbonate polyol with Mn=2000 using 3-methyl-1,5-pentanediol/1,6-hexanediol = 90/10 (molar ratio), manufactured by Kuraray Co., Ltd.], Kuraray Polyol C-3090 [Polycarbonate polyol with Mn=3000 using 3-methyl-1,5-pentanediol/1,6-hexanediol, manufactured by Kuraray Co., Ltd.], Kuraray Polyol Examples include C-2050 [a polycarbonate polyol with Mn=2000 using 3-methyl-1,5-pentanediol/1,6-hexanediol = 50/50 (molar ratio), manufactured by Kuraray Co., Ltd.] and BENEBiOL NL2010DB [a polycarbonate polyol with Mn=2000 using biomass-derived isosorbide].

The polyester polyol is not particularly limited, but examples include condensed polyester polyols, polylactone polyols, and castor oil-based polyols.

The condensation-type polyester polyol is not particularly limited, but examples include polyester polyols obtained by dehydration condensation of a polycarboxylic acid having 4 to 20 carbon atoms and a polyhydric alcohol having 2 to 20 carbon atoms, and polyester polyols obtained by dehydration condensation of an ester-forming derivative of a polycarboxylic acid having 4 to 20 carbon atoms and a polyhydric alcohol having 2 to 20 carbon atoms.

Polyhydric alcohols with 2 to 20 carbon atoms are not particularly limited, but examples include dihydric alcohols such as ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 1,6-hexanediol, cyclohexanedimethanol, 3-methylpentanediol, diethylene glycol, neopentyl glycol, 1,4-bis(hydroxymethyl)cyclohexane, 1,4-bis(hydroxyethyl)benzene, and 2,2-bis(4,4'-hydroxycyclohexyl)propane; trihydric alcohols such as glycerin and trimethylolpropane; and tetrahydric to octahydric alcohols such as pentaerythritol, diglycerin, α-methylglucoside, sorbitol, xylitol, mannitol, dipentaerythritol, glucose, fructose, and sucrose.

Furthermore, the polycarboxylic acids having 4 to 20 carbon atoms or their ester-forming derivatives are not particularly limited, but examples include aliphatic dicarboxylic acids (succinic acid, adipic acid, azelaic acid, sebacic acid, fumaric acid, and maleic acid, etc.), alicyclic dicarboxylic acids (dimer acids, etc.), aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, etc.), trivalent or higher polycarboxylic acids (trimellitic acid and pyromellitic acid, etc.), their anhydrides (succinic anhydride, maleic anhydride, phthalic anhydride, and trimellitic anhydride, etc.), their acid halides (adipic acid dichloride, etc.), their low molecular weight alkyl esters (dimethyl succinate and dimethyl phthalate, etc.), and mixtures thereof.

The polylactone polyol is not particularly limited, but examples include polyadditions of lactones to polyhydric alcohols having 2 to 20 carbon atoms, with lactones having 4 to 12 carbon atoms (e.g., γ-butyrolactone, γ-valerolactone, and ε-caprolactone). Specific examples of polylactone polyols include polycaprolactone diols, polyvalerolactone diols, and polycaprolactone triols.

Castor oil-based polyols are not particularly limited, but include, for example, castor oil and polyols or modified castor oil modified with an AO (organic oxide) having 2 to 12 carbon atoms. Modified castor oil can be produced by transesterification and/or AO addition of castor oil and polyol. Examples of castor oil-based polyols include castor oil, trimethylolpropane-modified castor oil, pentaerythritol-modified castor oil, and EO adducts of castor oil (4 to 30 moles added).

The AO having 2 to 12 carbon atoms is not particularly limited, but examples include EO, PO, 1,2-, 2,3- or 1,3-butylene oxide, tetrahydrofuran, 3-methyltetrahydrofuran, α-olefin oxide, styrene oxide, and epihalohydrins (such as epichlorohydrin).

The polyolefin polyol is not particularly limited, but examples include polybutadiene polyol, hydrogenated polybutadiene polyol, polyisoprene polyol, hydrogenated polyisoprene polyol, and hydroxyl group-modified polyolefins obtained by reacting an acid-modified polyolefin (obtained by modifying a polyolefin with an unsaturated (poly)carboxylic acid (anhydride), as described in, for example, Japanese Patent Application Publication No. 2018-076428, with an amino alcohol.

There are no particular restrictions on commercially available polyolefin polyols, but examples include the NISSO-PB G series [polybutadiene polyol, manufactured by Nippon Soda Co., Ltd.], the Poly bd series [polybutadiene polyol, manufactured by Idemitsu Kosan Co., Ltd.], the NISSO-PB GI series [hydrogenated polybutadiene polyol, manufactured by Nippon Soda Co., Ltd.], Polytail H [hydrogenated polybutadiene polyol, manufactured by Mitsubishi Chemical Corporation], the Poly ip series [polyisoprene polyol, manufactured by Idemitsu Kosan Co., Ltd.], and the EPOL series [hydrogenated polyisoprene polyol, manufactured by Idemitsu Kosan Co., Ltd.].

The diol (f2) having a carboxyl group and/or a carboxylate anion group is not particularly limited, but examples include a diol having one carboxyl group, a diol having two or more carboxyl groups, and a salt obtained by neutralizing the above diol with a neutralizing agent described later.
Examples of diols having one carboxyl group include 2,2'-dimethylolpropionic acid, 2,2'-dimethylolbutanoic acid, 2,2'-dimethylolbutyric acid, and 2,2'-dimethylolvaleric acid.
Examples of diols having two or more carboxyl groups include tartaric acid.

Examples of neutralizing agents used for neutralizing diols having a carboxyl group and/or a carboxylate anion group include ammonia, amine compounds having 1 to 20 carbon atoms, and hydroxides of alkali metals (such as sodium, potassium, and lithium).
Examples of amine compounds having 1 to 20 carbon atoms include primary amines such as monomethylamine, monoethylamine, monobutylamine, monoethanolamine, and 2-amino-2-methyl-1-propanol; secondary amines such as dimethylamine, diethylamine, dibutylamine, diethanolamine, and N-methyldiethanolamine; and tertiary amines such as trimethylamine, triethylamine, dimethylethylamine, and triethanolamine.
Of these, ammonia and amine compounds having 1 to 20 carbon atoms are preferred from the viewpoint of the drying properties of the resulting aqueous resin dispersion and the water resistance of the resulting film, and more preferred are ammonia, monomethylamine, monoethylamine, dimethylamine, diethylamine, trimethylamine, triethylamine, and dimethylethylamine.

The weight percentage of the active hydrogen group-containing compound is preferably 0 to 50% by weight, more preferably 1 to 40% by weight, and particularly preferably 1 to 30% by weight, relative to the total weight of the resin (P), from the viewpoint of the volume-average particle size of the aqueous resin dispersion and storage stability.

Examples of chain extenders (g) include water, C2-C10 diamines (e.g., ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, toluenediamine, and piperazine), C2-C10 polyalkylene polyamines (e.g., diethylenetriamine, triethylenetetramine, and tetraethylenepentamine), hydrazine or its derivatives (dibasic acid dihydrazides, e.g., adipic acid dihydrazide), C2-C30 polyepoxy compounds (e.g., 1,6-hexanediol diglycidyl ether, trimethylolpropane polyglycidyl ether, etc.), and C2-C10 amino alcohols (e.g., ethanolamine, diethanolamine, 2-amino-2-methylpropanol, and triethanolamine). C2-C10 diamines are preferred as chain extenders, secondary diamines are more preferred, and isophoronediamine is even more preferred. When the resin (P) contains the above compound as a constituent monomer, the cohesive force of the urethane group portion is improved, reducing the degree of swelling in water, thus exhibiting excellent boil and retort resistance. Furthermore, the use of diamines is preferable because the elongation reaction by the amine suppresses the generation of carbon dioxide, reducing the amount of amine carbonate salt produced and improving storage stability.

If the resin (P) is formed by the polycondensation of a carboxylic acid component (a) and an amino alcohol (b), and the hydroxyl groups at the ends of the resin react with polyisocyanate, resulting in a resin (p3) where the Y in general formula (1) at the end becomes a urethane group, then the structure will have a urethane group at the end of the constituent unit represented by general formula (3).
In this case, the average number of repeating units represented by general formula (3) is preferably 1 to 100, more preferably 1 to 50, and particularly preferably 1 to 20.
Furthermore, the number-average molecular weight of the resin (p3) is preferably 2,000 to 100,000, more preferably 5,000 to 100,000, and particularly preferably 10,000 to 100,000.

In the resin (p3), the weight percentage of the constituent unit represented by general formula (1) is preferably 10-90%, more preferably 20-90%, and even more preferably 40-80%. A higher weight percentage of the constituent unit represented by general formula (1) improves adhesion to OPP.

The amide group content of the resin (p3) is preferably 0.1 to 2.5 mmol/kg, more preferably 0.2 to 2.0 mmol/kg, and even more preferably 0.3 to 1.2 mmol/kg. A higher proportion of amide groups improves blocking resistance and boil resistance, and enhances adhesion to nylon.

The resin (p3) may or may not contain ester groups. The ester group content in the resin (p3) is preferably 0 to 3.0 mmol/kg, more preferably 0 to 2.0 mmol/kg, and even more preferably 0 to 1.0 mmol/kg. If the resin (p3) contains ester groups, the ester group content is preferably 0.1 to 3.0 mmol/kg. A higher proportion of ester groups improves adhesion to PET.

The urethane group content of the resin (p3) is preferably 1.0 to 6.0 mmol/kg, and more preferably 2.0 to 5.0 mmol/kg. A higher proportion of urethane groups improves adhesion to PET and nylon.

The resin (p3) may contain urea groups, and the urea group content in the resin (p3) is preferably 0 to 1.5 mmol/kg, more preferably 0 to 1.0 mmol/kg. A higher proportion of urea groups improves adhesion to PET.

When resin (P) is formed by the polycondensation of an amine component (c) and a hydroxy acid (d), the hydroxyl groups at the ends of the resin react with polyisocyanate, resulting in a resin (p4) where Y in general formula (1) is a urethane group, the structure is formed when multiple hydroxy acids are polycondensed with one molecule of amine, and the hydroxyl groups at the ends of the structure react with polyisocyanate. When the amine component is a diamine, two molecules of hydroxy acid react with one molecule of amine.
Furthermore, the number-average molecular weight of the resin (p4) is preferably 2,000 to 100,000, more preferably 5,000 to 100,000, and particularly preferably 10,000 to 100,000.

In the resin (p4), the weight percentage of the constituent unit represented by general formula (1) is preferably 10-90%, more preferably 20-90%, and even more preferably 40-80%. A higher weight percentage of the constituent unit represented by general formula (1) improves adhesion to OPP.

The amide group content of the resin (p4) is preferably 0.1 to 2.5 mmol/kg, more preferably 0.2 to 2.0 mmol/kg, and even more preferably 0.3 to 1.2 mmol/kg. A higher proportion of amide groups improves blocking resistance and boil resistance, and enhances adhesion to nylon.

It is preferable that the resin (p4) does not contain ester groups.

The urethane group content of the resin (p4) is preferably 1.0 to 6.0 mmol/kg, and more preferably 2.0 to 5.0 mmol/kg. A higher proportion of urethane groups improves adhesion to PET and nylon.

The resin (p4) may contain urea groups, and the urea group content in the resin (p4) is preferably 0 to 1.5 mmol/kg, more preferably 0 to 1.0 mmol/kg. A higher proportion of urea groups improves adhesion to PET.

In one embodiment, the biomass concentration in the resin (P) is preferably 20% by weight or more, more preferably 40% by weight or more, and even more preferably 60% by weight or more, from the viewpoint of addressing the depletion of petroleum resources and considering environmental concerns. The above biomass concentration refers to the weight ratio (percentage) of the biomass-derived constituent monomers used relative to the weight of the resin (P).

The method for producing the aqueous resin dispersion of the present invention is not particularly limited, as long as it includes a step of mixing the organic solvent solution of the resin (P) obtained by the production method of the present invention with an aqueous medium.

Examples of methods for producing an aqueous resin dispersion containing resin (P) include the following methods [1] to [5].

[1] A method for producing a resin solution by dissolving resin (P) in an organic solvent, then, if necessary, dispersing the carboxyl groups of resin (P) as a salt using a neutralizing agent such as triethylamine in an aqueous medium, and then, if necessary, distilling off the organic solvent.

[2] A method for producing a polyurethane-modified resin (P) by polycondensing a carboxylic acid component (a) and an amino alcohol (b), reacting the terminal hydroxyl groups with a polyisocyanate, and optionally a chain extender, in one or multiple steps in the presence or absence of an organic solvent, and then dispersing the carboxyl groups as salts using a neutralizing agent such as triethylamine in an aqueous medium, followed by distillation of the organic solvent as necessary.

[3] A method comprising: polycondensing a carboxylic acid component (a) and an amino alcohol (b); reacting the terminal hydroxyl groups with a polyisocyanate in one or multiple steps, in or without the presence of an organic solvent, to produce a prepolymer having isocyanate groups; then, if necessary, dispersing the carboxyl groups in the prepolymer as a salt in an aqueous medium using a neutralizing agent such as triethylamine; reacting the chain extender with the isocyanate groups; and, if necessary, distilling off the organic solvent.

[4] A method for producing a polyurethane-modified resin (P) by polycondensing an amine component (c) and a hydroxy acid (d), reacting the terminal hydroxyl group with a polyisocyanate, and optionally a chain extender, in one or multiple steps, in the presence or absence of an organic solvent, and dispersing the carboxyl group as a salt with a neutralizing agent such as triethylamine in an aqueous medium, and then distilling off the organic solvent as necessary.

[5] A method comprising: polycondensing an amine component (c) and a hydroxy acid (d); reacting the terminal hydroxyl group with a polyisocyanate in one or multiple steps, in the presence or absence of an organic solvent, to produce a prepolymer having an isocyanate group; then, if necessary, dispersing the carboxyl group in the prepolymer as a salt in an aqueous medium with a neutralizing agent such as triethylamine; reacting the chain extender with the isocyanate group; and, if necessary, distilling off the organic solvent.

Of methods [1] to [5], method [3] is preferred from the viewpoint of storage stability of the aqueous resin dispersion (Q) and mechanical strength of the dried film.

In the case of [1], in the step of dispersing the resin (P) in an aqueous medium, it is preferable to use a rotary dispersion and mixing apparatus as described later, and the temperature is preferably 60°C or lower, and more preferably 40°C or lower. The dispersion time can be appropriately selected depending on the apparatus used, but generally 1 minute to 2 hours is preferred, and 3 minutes to 1 hour is even more preferred.
In cases [2] to [5], the formation of the polyurethane-modified resin (P) is preferably carried out by a reaction at 20°C to 150°C, more preferably 60°C to 110°C, and the reaction time is preferably 2 to 20 hours.
The formation of the polyurethane-modified resin (P) can be carried out in or without the presence of an organic solvent, as described later, but it is preferable to carry it out in or without the presence of an organic solvent that is substantially inactive with isocyanate groups, and methyl ethyl ketone is more preferable.

Examples of organic solvents that are substantially non-reactive with isocyanate groups include ketone solvents, ester solvents, ether solvents, amide solvents, and aromatic hydrocarbon solvents.

In the production of aqueous resin dispersions, catalysts commonly used in conventional urethane reactions may be used to accelerate the reaction of the polyurethane-modified resin (P) as needed. Examples of catalysts include amine catalysts, such as triethylamine, N-ethylmorpholine, triethylenediamine, and cycloamidines described in U.S. Patent No. 4,524,104 [e.g., 1,8-diazabicyclo(5,4,0)undecene-7 (manufactured by Sunapro, DBU)]; tin-based catalysts, such as dibutyltin dilaurylate, dioctyltin dilaurylate, and tin octoate; and titanium-based catalysts, such as tetrabutoxytitanate.

In the method for producing an aqueous resin dispersion of the present invention, examples of organic solvents for the organic solvent solution of resin (P) include aromatic hydrocarbon solvents, aliphatic or alicyclic hydrocarbon solvents, halogen solvents, esters, ester ether solvents, ether solvents, ketone solvents, alcohol solvents, amide solvents, sulfoxide solvents, heterocyclic compound solvents, and mixed solvents of two or more of these.
Specific examples of organic solvents include aromatic hydrocarbon solvents (toluene, xylene, ethylbenzene, and tetralin, etc.); aliphatic or alicyclic hydrocarbon solvents (n-hexane, n-heptane, mineral spirits, and cyclohexane, etc.); halogen solvents such as methyl chloride, methyl bromide, methyl iodide, methylenedichloride, carbon tetrachloride, trichloroethylene, and perchloroethylene; ester or ester ether solvents such as ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, and ethyl cellosolve acetate; diethyl ether, tetrahydrofuran, dioxane, ethyl cellosolve, butyl acetate Examples of organic solvents include ether solvents such as Rosolve and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, and cyclohexanone; alcohol solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 2-ethylhexyl alcohol, and benzyl alcohol; amide solvents such as dimethylformamide and dimethylacetamide; sulfoxide solvents such as dimethyl sulfoxide; heterocyclic compound solvents such as N-methylpyrrolidone; and mixed solvents of two or more of these. Among the above organic solvents, volatile ones with a boiling point of less than 100°C are preferred. Preferred organic solvents include ethyl acetate, acetone, tetrahydrofuran, and methyl ethyl ketone.

The amount of organic solvent used per 100 parts by weight of resin (P) is preferably 25 to 300 parts by weight, more preferably 25 to 150 parts by weight, and even more preferably 25 to 100 parts by weight.

In the method for producing the aqueous resin dispersion of the present invention, the aqueous solvent used in the step of mixing the organic solvent solution of the resin (P) with an aqueous solvent can be any liquid in which water is an essential component, without limitation. Examples of such solvents include water, aqueous solutions of organic solvents, aqueous solutions of surfactants (s) (described later), aqueous solutions of water-soluble polymers (t), and mixtures of two or more of these.

To improve the dispersibility of resin (P) in aqueous solvents, a neutralizing agent may be used to neutralize the carboxyl groups of resin (P). Examples of neutralizing agents include those used for neutralizing diols having carboxyl groups and/or carboxylate anion groups.

The amount of neutralizing agent used is preferably 1 to 150 mol%, more preferably 5 to 100 mol%, relative to the carboxyl groups of the resin (P), from the viewpoint of dispersibility.

When dispersing the resin (P) in an aqueous solvent, known surfactants (s) and inorganic dispersants can be used as emulsifiers or dispersants as needed.

The surfactant (s) is not particularly limited and includes anionic surfactants (s-1), cationic surfactants (s-2), amphoteric surfactants (s-3), and nonionic surfactants (s-4). The surfactant (s) may also be a combination of two or more surfactants.

Examples of anionic surfactants (s-1) include carboxylic acids or their salts, sulfate esters, carboxymethyl salts, sulfonates, and phosphate esters.
Examples of cationic surfactants (S-2) include quaternary ammonium salt type surfactants and amine salt type surfactants.
Examples of amphoteric surfactants (S-3) include carboxylate-type amphoteric surfactants, sulfate-type amphoteric surfactants, sulfonate-type amphoteric surfactants, and phosphate-type amphoteric surfactants.
Examples of nonionic surfactants (s-4) include AO-added nonionic surfactants and polyhydric alcohol-type nonionic surfactants.
Specific examples of these surfactants (s) include those described in Japanese Patent Publication No. 2002-284881.

Examples of inorganic dispersants include polyvalent metal phosphate salts such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, and hydroxyapatite; carbonates such as calcium carbonate and magnesium carbonate; inorganic salts such as calcium metasilicate, calcium sulfate, and barium sulfate; and inorganic compounds such as magnesium hydroxide and aluminum hydroxide.

When dispersing resin (P) in an aqueous solvent, a known water-soluble polymer (t) can be used as an emulsifier or dispersant.

Examples of water-soluble polymers (t) include cellulose compounds (e.g., methylcellulose, ethylcellulose, hydroxyethylcellulose, ethylhydroxyethylcellulose, carboxymethylcellulose, hydroxypropylcellulose, and their saponified products), gelatin, starch, dextrin, gum arabic, chitin, chitosan, polyethylene glycol, and the like.

The method of dispersion when mixing the organic solvent solution of the resin (P) of the present invention with an aqueous medium is not particularly limited, but it is preferable to use a rotary dispersion mixer, an ultrasonic disperser, or a kneader, and among these, a rotary dispersion mixer, which has particularly excellent dispersion capabilities, is even more preferable.

Examples of rotary dispersion mixing devices include those with common agitators such as MaxBlend and helical blades, as well as TK Homomixer [Primix Co., Ltd.], Creamix [M-Technique Co., Ltd.], Philmix [Primix Co., Ltd.], UltraTarlux [IKA Co., Ltd.], Ebara Milder [Ebara Corporation], Cavitron (Eurotech Co., Ltd.), and Biomixer [Nippon Seiki Co., Ltd.].

The amount of aqueous medium used per 100 parts by weight of the organic solvent solution of resin (P) is preferably 100 to 500 parts by weight, more preferably 150 to 400 parts by weight, and even more preferably 150 to 300 parts by weight.

The particle size of the particles in the aqueous resin dispersion is preferably 10 to 200 nm, more preferably 10 to 150 nm, and even more preferably 20 to 100 nm, from the viewpoint of inkjet head permeability and ink viscosity. In this invention, particle size refers to the volume-average particle size. The particle size can be measured and determined by light scattering measurement.

The aqueous resin dispersion of the present invention is preferably used as an aqueous resin dispersion for inkjet inks. Using the aqueous resin dispersion of the present invention as an inkjet ink is preferable because it exhibits good adhesion to recording media, and is preferable as an inkjet ink for flexible packaging printing from the viewpoint of image lamination strength and blocking resistance. Furthermore, due to its good boil and retort resistance, it can be used for retort pouches. Flexible packaging printing refers to printing on packaging materials made of flexible materials. Examples of packaging materials include thin, flexible materials such as plastic film, aluminum foil, and paper, which may be used individually or in combination. Packaging materials printed with flexible packaging printing are used, for example, as bags for food, pharmaceuticals, etc.

The aqueous ink (L) of the present invention contains the aqueous resin dispersion of the present invention. The aqueous ink (L) of the present invention can preferably be used as an inkjet ink.
Inkjet inks preferably contain pigments in addition to the aqueous resin dispersion of the present invention. Inkjet inks may also contain humectants, penetrating agents, etc.

The solid content of the aqueous resin dispersion of the present invention in the inkjet ink is preferably 0.1 to 60% by weight, more preferably 1 to 20% by weight, based on the weight of the inkjet ink. The content of the aqueous resin dispersion is preferably 1 to 90% by weight, more preferably 5 to 50% by weight, based on the weight of the inkjet ink.

The pigment content is preferably 0.1 to 30% by weight, more preferably 1 to 10% by weight, based on the weight of the inkjet ink. The humectant content is preferably 0.1 to 90% by weight, more preferably 1 to 50% by weight, based on the weight of the inkjet ink.

Examples of pigments include conventionally known organic and inorganic pigments (e.g., white pigments, black pigments, gray pigments, red pigments, brown pigments, yellow pigments, green pigments, blue pigments, purple pigments, and metallic pigments; synthetic organic pigments derived from natural organic pigments; nitroso pigments; nitro pigments; pigment-type azo pigments; azo lakes made from water-soluble dyes; azo lakes made from poorly soluble dyes; lakes made from basic dyes; lakes made from acid dyes; xanthan lakes; anthraquinone lakes; pigments and phthalocyanine pigments derived from vat dyes; and organic pigments such as daylight fluorescent pigments).

Examples of specific organic and inorganic pigments are given below. Examples of white pigments include inorganic pigments such as titanium dioxide, zinc oxide, zinc sulfide, antimony oxide, and zirconium oxide. In addition to inorganic pigments, hollow resin microparticles and polymer microparticles can also be used. The average particle size of the pigment is preferably 200 to 300 nm. If the average particle size is less than 200 nm, the opacity tends to be insufficient, and if it exceeds 300 nm, the discharge stability tends to be insufficient.

In particular, titanium dioxide is preferred from the viewpoint of opacity. Similarly, the average particle size of the titanium dioxide is preferably 200 to 300 nm.

While not particularly limited, the following pigments are used for magenta: C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 48:1, C.I. Pigment Red 53:1, C.I. Pigment Red 57:1, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 139, C.I. Pigment Red 144, C.I. Pigment Red 149, C.I. Pigment Red 166, C.I. Pigment Red 177, C. Examples include I. Pigment Red 178 and C. I. Pigment Red 222.

While not particularly limited, examples of pigments for yellow include C.I. Pigment Orange 31, C.I. Pigment Orange 43, C.I. Pigment Yellow 12, C.I. Pigment Yellow 13, C.I. Pigment Yellow 14, C.I. Pigment Yellow 15, C.I. Pigment Yellow 17, C.I. Pigment Yellow 74, C.I. Pigment Yellow 93, C.I. Pigment Yellow 94, C.I. Pigment Yellow 128, C.I. Pigment Yellow 138, and Pigment Yellow 180.

Pigments for cyan are not particularly limited, but examples include C.I. Pigment Blue 15, C.I. Pigment Blue 15:2, C.I. Pigment Blue 15:3, C.I. Pigment Blue 16, C.I. Pigment Blue 60, and C.I. Pigment Green 7.

Moisturizers are used as moisturizing ingredients in inkjet inks.
Examples of humectants, though not particularly limited, include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, pentamethylene glycol, trimethylene glycol, 2-butene-1,4-diol, 2-ethyl-1,3-hexanediol, 2-methyl-2,4-pentanediol, tripropylene glycol, polyethylene glycol with Mn of 2,000 or less, 1,3-propylene glycol, isopropylene glycol, isobutylene glycol, glycerin, mesoerythritol, pentaerythritol, 2-pyrrolidone, N-methyl-2-pyrrolidone, and N-ethyl-2-pyrrolidone. A single humectant may be used, or two or more may be used in combination.

Penetrants play a role in promoting the penetration of inkjet ink into permeable media. Penetrants are not particularly limited, but examples include glycol ethers (ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol mono-t-butyl ether, triethylene glycol monobutyl ether, 1-methyl-1-methoxybutanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol monobutyl ether, etc.) and aliphatic diols having 4 to 8 carbon atoms (1,2-alkyl diols such as 1,2-pentanediol and 1,2-hexanediol, and 1,3 Examples of surfactants include organic solvents such as linear alcohols (propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, and 1,8-octanediol); acetylene glycol-based surfactants; acetylene alcohol-based surfactants; ether-based surfactants such as polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene dodecylphenyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether, and polyoxyalkylene alkyl ether; ester-based surfactants such as polyoxyethylene oleic acid, polyoxyethylene oleic acid ester, polyoxyethylene distearate ester, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate, and polyoxyethylene stearate; silicone-based surfactants such as dimethylpolysiloxane; and fluorine-based surfactants such as fluorine alkyl esters and perfluoroalkyl carboxylates. Penetrating agents may be used individually or in combination of two or more types.

In addition to the resin (P) in the aqueous resin dispersion of the present invention, other aqueous media dispersible resins or water-soluble resins may be used in combination with the inkjet ink, if necessary, for purposes such as assisting in film formation or improving binder function.

Other aqueous media-dispersible or water-soluble resins used in combination with inkjet inks include, for example, polyester resins, polyacrylic resins, and polyurethane resins other than resin (P) in the present invention that are aqueous media-dispersible or water-soluble.

Inkjet ink may further contain one or more of the following: pH adjusters, viscosity adjusters, defoamers, preservatives, degradation inhibitors, stabilizers, antifreeze agents, and water.

Other additives include chelating agents, preservatives, and pH adjusters. Examples of chelating agents include ethylenediaminetetraacetate (EDTA), ethylenediamine nitrilotriacetate, hexametaphosphate, pyrophosphate, or metaphosphate.

Examples of preservatives include sodium benzoate, sodium pentachlorophenol, sodium 2-pyridinethiol-1-oxide, sodium sorbate, sodium dehydroacetate, and 1,2-dibenzinthiazolin-3-one.

Examples of pH adjusting agents include potassium dihydrogen phosphate, disodium hydrogen phosphate, sodium hydroxide, lithium hydroxide, potassium hydroxide, ammonia, diethanolamine, triethanolamine, triisopropanolamine, potassium carbonate, sodium carbonate, and sodium bicarbonate.

In addition to inkjet printing, the present invention also includes conventional printing methods such as special gravure printing, offset printing, and thermal transfer printing, which are used for printing plastic films.

The recording medium used for printing with water-based ink (L) is not particularly limited, but examples include non-permeable and permeable recording media. Examples of non-permeable recording media include resin media such as polycarbonate, rigid PVC, flexible PVC, polystyrene, expanded polystyrene, polymethyl methacrylate, polypropylene, polyethylene, polyethylene terephthalate, and nylon, as well as metal media such as glass and stainless steel.

Furthermore, while there are no particular limitations on the permeable recording medium, examples include paper media such as high-quality paper, art paper, coated paper, and cast-coated paper.

Among these, non-permeable recording media are preferred for use in printing with water-based ink (L) from the viewpoint of adhesion, and resin media are more preferred. Furthermore, resin media are suitable for flexible packaging printing from the viewpoint of lamination strength and blocking resistance.

Flexible packaging printing refers to printing on flexible recording media such as resin films, either individually or in laminated form. Printed materials using flexible packaging printing are used for packaging food, household goods, and other similar items.

This specification discloses the following:

The present disclosure (1) is an aqueous resin dispersion (Q) containing a resin (P) having a constituent unit represented by general formula (1).
[In general formula (1), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms, R2 is an aliphatic alkylene group having 1 to 6 carbon atoms, X is an amide group, and Y is an ester group or a urethane group.]

Disclosure (2) is an aqueous ink (L) containing the aqueous resin dispersion described in Disclosure (1).

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Hereinafter, unless otherwise specified, "parts" refers to parts by weight.

<Example 1> [Production of aqueous resin dispersion (Q-1)]
In a reaction vessel equipped with a condenser, thermometer, stirrer, and nitrogen inlet tube, 89.0 parts of dimer acid (Pripol 1009: manufactured by CRODA) as the carboxylic acid component and 11.0 parts of N-methylethanolamine as the amino alcohol were added (the amounts are listed in parts by weight after subtracting the amount to be distilled off, as described below. The same applies to the following examples and comparative examples.) and the reaction was carried out at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water to obtain resin (P-1). Next, 50 parts of tetrahydrofuran were added and heated to 70°C and stirred to prepare a tetrahydrofuran solution of resin (P-1). Then, 2.1 parts of triethylamine as a neutralizing agent were added and homogenized, and then 238 parts of ion-exchanged water as an aqueous medium were added while stirring at 200 rpm to disperse in water. The obtained dispersion was heated to 60°C under reduced pressure and the tetrahydrofuran was distilled off. Subsequently, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q-1). The raw materials used and their quantities are shown in Table 1.

<Examples 2-4> [Production of aqueous resin dispersions (Q-2) to (Q-4)]
The carboxylic acid components and amino alcohols listed in Table 1 were charged into a reaction vessel equipped with a condenser, a stirrer, and a nitrogen inlet pipe. The reaction was carried out in the same manner as in Example 1, otherwise yielding aqueous resin dispersions (Q-2) to (Q-4). The raw materials used and their quantities are shown in Table 1.

<Example 5> [Production of aqueous resin dispersion (Q-5)]
In a reaction vessel equipped with a condenser, thermometer, stirrer, and nitrogen inlet, 14.8 parts of lactic acid as a hydroxy acid and 82.8 parts of dimer amine (Priamine 1075: manufactured by CRODA) as an amine component were added and reacted at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. Next, the mixture was reacted under reduced pressure of 0.5 to 2.5 kPa while distilling off the water. Further, 2.4 parts of trimellitic anhydride were added and the mixture was reacted while distilling off the water. The reactants were removed from the reaction vessel to obtain resin (P-5). Next, 50 parts of tetrahydrofuran were added and heated to 70°C and stirred to prepare a tetrahydrofuran solution of resin (P-5). Then, 3.0 parts of triethylamine as a neutralizing agent were added and homogenized, and then 240 parts of ion-exchanged water as an aqueous medium were added while stirring at 200 rpm to disperse the mixture in water. The resulting dispersion was heated under reduced pressure to 60°C and the tetrahydrofuran was distilled off. Subsequently, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q-5). The raw materials used and their quantities are shown in Table 1.

<Example 6> [Production of aqueous resin dispersion (Q-6)]
The reaction was carried out in the same manner as in Example 5, except that the hydroxy acid, amine component, and trimellitic anhydride listed in Table 1 were used, to obtain an aqueous resin dispersion (Q-6). The raw materials used and their quantities are shown in Table 1.

<Example 7> [Production of aqueous resin dispersion (Q-7)]
In a simple pressurized reaction apparatus equipped with a condenser, thermometer, stirrer, and nitrogen inlet tube, 20.9 parts of dimer acid (Pripol 1009: manufactured by CRODA) as the carboxylic acid component and 4.1 parts of N-methylethanolamine as the amino alcohol were added, and the reaction was carried out at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water and unreacted amino alcohol. Next, 52.8 parts of isophorone diisocyanate as the polyisocyanate, 17.7 parts of neopentyl glycol as the active hydrogen component, 4.5 parts of dimethylolpropionic acid, and 50.5 parts of tetrahydrofuran as the reaction organic solvent were charged, and the mixture was stirred at 70°C for 12 hours to carry out the urethane formation reaction, thereby producing a tetrahydrofuran solution of a urethane prepolymer having isocyanate groups.
Next, 3.4 parts of triethylamine were added to the tetrahydrofuran solution of the obtained urethane prepolymer as a neutralizing agent to homogenize it. Then, 244 parts of ion-exchanged water were added as an aqueous medium while stirring at 200 rpm to disperse the polyurethane prepolymer in water. Next, 1.4 parts of isophorone diamine were added to the obtained dispersion as a chain extender, and the mixture was heated to 50°C and stirred for 4 hours to carry out a chain extension reaction by the reaction of water or the chain extender with the isocyanate group. The mixture was then heated under reduced pressure to 60°C to remove the tetrahydrofuran, which was the organic solvent used in the reaction. After that, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q-7). The raw materials used and their amounts are shown in Table 2.

<Examples 8-11 and 14> [Production of aqueous resin dispersions (Q-8) to (Q-11) and (Q-14)]
The raw materials listed in Table 2 were placed in a simple pressurized reaction apparatus equipped with a cooling tube, thermometer, stirrer, and nitrogen inlet tube. The reaction was carried out in the same manner as in Example 7, otherwise yielding aqueous resin dispersions (Q-8) to (Q-11) and (Q-14). The raw materials used and their quantities are shown in Table 2.

<Example 12> [Production of aqueous resin dispersion (Q-12)]
In a simple pressurized reaction apparatus equipped with a condenser, thermometer, stirrer, and nitrogen inlet tube, 7.1 parts of lactic acid as a hydroxy acid and 42.9 parts of dimer amine (Priamine 1075: manufactured by CRODA) as an amine component were added, and the reaction was carried out at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water. Next, 38.0 parts of isophorone diisocyanate as a polyisocyanate, 7.0 parts of neopentyl glycol as an active hydrogen component, 4.9 parts of dimethylolpropionic acid, and 50.6 parts of methyl ethyl ketone as an organic solvent for the reaction were charged, and the mixture was stirred at 70°C for 12 hours to carry out the urethane formation reaction, thereby producing a methyl ethyl ketone solution of a urethane prepolymer having isocyanate groups.
Next, 3.3 parts of diethylaminoethanol were added to the methyl ethyl ketone solution of the obtained urethane prepolymer as a neutralizing agent to homogenize it. Then, 247 parts of ion-exchanged water as an aqueous medium were added while stirring at 200 rpm to disperse the polyurethane prepolymer in water. Next, 2.8 parts of isophorone diamine were added to the obtained dispersion as a chain extender, and the mixture was heated to 50°C and stirred for 4 hours to carry out a chain extension reaction by the reaction of water or the chain extender with the isocyanate group. The mixture was then heated under reduced pressure to 60°C to remove the methyl ethyl ketone, which was the organic solvent used in the reaction. After that, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q-12). The raw materials used and the amounts used are shown in Table 2.

<Example 13> [Production of aqueous resin dispersion (Q-13)]
In a reaction vessel equipped with a condenser, thermometer, stirrer, and nitrogen inlet, 89.0 parts of dimer acid (Pripol 1009: manufactured by CRODA) as the carboxylic acid component and 11.0 parts of N-methylethanolamine as the amino alcohol were added and reacted at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water to obtain resin (P-13). Next, 50 parts of tetrahydrofuran were charged and heated to 70°C and stirred to prepare a tetrahydrofuran solution of resin (P-13). Then, 1.2 parts of potassium hydroxide as a neutralizing agent and 12 parts of deionized water were added and homogenized, and then 226 parts of deionized water as an aqueous medium were added while stirring at 200 rpm and dispersed in water. The obtained dispersion was heated to 60°C under reduced pressure and the tetrahydrofuran was distilled off. After that, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q-13). Table 1 shows the raw materials used and their quantities.

<Comparative Example 1> [Production of aqueous resin dispersion (Q'-1)]
In a reaction vessel equipped with a condenser, thermometer, stirrer, and nitrogen inlet, 91.5 parts of dimer acid (Pripol 1009: manufactured by CRODA) as the carboxylic acid component and 8.5 parts of ethylenediamine as the amine component were added and reacted at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water to obtain resin (P'-1). Next, 50.5 parts of tetrahydrofuran were added and heated to 70°C and stirred to prepare a tetrahydrofuran solution of resin (P'-1). Then, 3.8 parts of triethylamine as a neutralizing agent were added and homogenized, and then 233 parts of ion-exchanged water as an aqueous medium were added while stirring at 200 rpm and dispersed in water. The obtained dispersion was heated to 60°C under reduced pressure and the tetrahydrofuran was distilled off. After that, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q'-1). Table 3 shows the raw materials used and their quantities.

<Comparative Example 2> [Production of aqueous resin dispersion (Q'-2)]
In a simple pressurized reaction apparatus equipped with a condenser, thermometer, stirrer, and nitrogen inlet tube, 43.2 parts of dimer acid (Pripol 1009: manufactured by CRODA) as the carboxylic acid component and 6.8 parts of ethylenediamine as the amine component were added, and the reaction was carried out at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water and unreacted amine components. Next, 38.1 parts of isophorone diisocyanate as the polyisocyanate, 6.9 parts of neopentyl glycol as the active hydrogen component, 4.9 parts of dimethylolpropionic acid, and 50.5 parts of tetrahydrofuran as the reaction organic solvent were charged, and the mixture was stirred at 70°C for 12 hours to carry out the urethane formation reaction, thereby producing a tetrahydrofuran solution of a urethane prepolymer having isocyanate groups.
Next, 3.7 parts of triethylamine were added to the tetrahydrofuran solution of the obtained urethane prepolymer as a neutralizing agent to homogenize it. Then, 249 parts of ion-exchanged water were added as an aqueous medium while stirring at 200 rpm to disperse the polyurethane prepolymer in water. Next, 2.8 parts of isophorone diamine were added to the obtained dispersion as a chain extender, and the mixture was heated to 50°C and stirred for 4 hours to carry out a chain extension reaction by the reaction of water or the chain extender with the isocyanate group. The mixture was then heated under reduced pressure to 60°C to remove the tetrahydrofuran, which was the organic solvent used in the reaction. After that, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q'-2). The raw materials used and their amounts are shown in Table 3.

<Comparative Example 3> [Production of aqueous resin dispersion (Q'-3)]
In a simple pressurized reaction apparatus equipped with a condenser, thermometer, stirrer, and nitrogen inlet tube, 9.6 parts of dodecanedioic acid as the carboxylic acid component and 20.4 parts of 1,4-butanediol as the diol were added, and the reaction was carried out at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water and unreacted amine components. Next, 51.0 parts of isophorone diisocyanate as the polyisocyanate, 14.1 parts of neopentyl glycol as the active hydrogen component, 4.9 parts of dimethylolpropionic acid, and 50.5 parts of methyl ethyl ketone as the reaction organic solvent were charged, and the reaction was carried out by stirring at 70°C for 12 hours to produce a methyl ethyl ketone solution of a urethane prepolymer having isocyanate groups.
Next, 3.3 parts of diethylaminoethanol were added to the methyl ethyl ketone solution of the obtained urethane prepolymer as a neutralizing agent to homogenize it. Then, 250 parts of ion-exchanged water were added as an aqueous medium while stirring at 200 rpm to disperse the polyurethane prepolymer in water. Next, 3.9 parts of isophorone diamine were added to the obtained dispersion as a chain extender, and the mixture was heated to 50°C and stirred for 4 hours to carry out a chain extension reaction by the reaction of water or the chain extender with the isocyanate group. The mixture was then heated under reduced pressure to 60°C to remove the methyl ethyl ketone, which was the organic solvent used in the reaction. After that, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q'-3). The raw materials used and their amounts are shown in Table 3.

<Comparative Example 4> [Production of aqueous resin dispersion (Q'-4)]
In a reaction vessel equipped with a condenser, thermometer, stirrer, and nitrogen inlet, 87.2 parts of dimer acid (Pripol 1009: manufactured by CRODA) as the carboxylic acid component and 12.8 parts of 1,4-butanediol as the diol were added and reacted at 200°C under a nitrogen stream for 6 hours while distilling off the water produced. The reaction was further carried out under reduced pressure of 0.5 to 2.5 kPa while distilling off the water to obtain resin (P'-4). Next, 50.5 parts of tetrahydrofuran were added and heated to 70°C and stirred to prepare a tetrahydrofuran solution of resin (P'-4). Then, 2.0 parts of triethylamine as a neutralizing agent were added and homogenized, and then 238 parts of ion-exchanged water as an aqueous medium were added while stirring at 200 rpm and dispersed in water. The obtained dispersion was heated to 60°C under reduced pressure and the tetrahydrofuran was distilled off. After that, water was added to adjust the solid content concentration to 30% by weight to obtain an aqueous resin dispersion (Q'-4). Table 3 shows the raw materials used and their quantities.

The composition of each raw material in Tables 1 to 3 is as follows:
• Prepol 1009: Biomass-derived dimer acid with 36 carbon atoms, made from vegetable oil [manufactured by CRODA]
• Prepol 1004: Biomass-derived dimer acid with 44 carbon atoms, made from vegetable oil [manufactured by CRODA]
• IPU-22: A biomass-derived dibasic acid with 22 carbon atoms, made from vegetable oil [Manufactured by Okamura Oil Co., Ltd.]
• Priamine 1075: A biomass-derived dimer amine with 36 carbon atoms, made from vegetable oil [manufactured by CRODA]
• Stavio PDI: Biomass-derived 1,5-pentamethylene diisocyanate [Manufactured by Mitsui Chemicals]
PTMG2000: Poly(oxytetramethylene) glycol with Mn=2,000 [manufactured by Mitsubishi Chemical Corporation]
• BioPTMG2000: Biomass-derived poly(oxytetramethylene) glycol with Mn=2,000 [Manufactured by Mitsubishi Chemical Corporation]
・Radianol 4713: Biomass-derived propylene glycol [Manufactured by OLEON]
• Biomass-derived 1,10-decanediamine made from castor oil [manufactured by Ogura Synthetic Industry Co., Ltd.]

The adhesion properties of the aqueous resin dispersions (Q-1) to (Q-14) and (Q'-1) to (Q'-4) were evaluated using the following method. The evaluation results are shown in Tables 1 to 3.

<Method for evaluating the adhesion of resin (P)>
Test specimens were prepared by coating surface-treated polypropylene film (OPP) [Toyobo Co., Ltd. "Pyrene P-2161" (thickness 30 μm)], surface-treated polyester film (PET) [Toyobo Co., Ltd. "Espet E-5102" (thickness 12 μm)], and surface-treated nylon film [Toyobo Co., Ltd. "Harden N-1130" (thickness 15 μm)] with aqueous resin dispersions (Q-1) to (Q-14) and (Q'-1) to (Q'-4) using a bar coater so that the thickness after drying was 2 μm, and drying at 90°C for 10 minutes to produce test specimens coated with polyurethane resin on each plastic film. In accordance with JIS K5600-5-6, 1 mm wide cuts were made on the dried surface of the aqueous resin dispersion of the prepared test specimens using a cutter knife so that 100 squares (10 x 10) were created, and a peel test was performed using transparent pressure-sensitive adhesive tape, and the number of squares remaining on the base film was counted. The more remaining cells there are, the better the adhesion of the polyurethane resin.

<Manufacturing of water-based inks (L-1) to (L-14), (L'-1), and (L'-4)>
In Examples 1 to 14 and Comparative Examples 1 to 4, 2.7 parts each of the aqueous resin dispersions (Q-1) to (Q-14) and (Q'-1) to (Q'-4), 2.5 parts of pigment [aqueous carbon black dispersion {Aqua-Black 162 manufactured by Tokai Carbon Co., Ltd., solid content concentration 20% by weight}], 1.0 part of glycerin as a humectant, 0.1 part of triethylene glycol, 0.1 part of 1,2-hexanediol as a penetrating agent, and 3.6 parts of water were placed in a container and mixed for 10 minutes to prepare aqueous inks (L-1) to (L-14) and comparative aqueous inks (L'-1) to (L'-4).

The permeability, abrasion resistance, blocking resistance, and boil resistance of water-based inks (L-1) to (L-14) and (L'-1) to (L'-4) were evaluated using the following method. The results are shown in Tables 1 to 3. Note that evaluation of abrasion resistance, blocking resistance, and boil resistance for (L'-1) and (L'-2) was discontinued because the ink clogged the print head nozzles of the inkjet printer described later.

<Method for evaluating the blocking resistance of water-based inks>
Surface-treated polypropylene film (OPP) [Toyobo Co., Ltd. "Pyrene P-2161" (thickness 30 μm)], surface-treated polyester film (PET) [Toyobo Co., Ltd. "Espet E-5102" (thickness 12 μm)], and surface-treated nylon film [Toyobo Co., Ltd. "Harden N-1130" (thickness 15 μm)] were printed with water-based inks (L-1) to (L-14) and (L'-3) to (L'-4) using an inkjet method, and then dried at 90°C for 10 minutes. An inkjet printer [Seiko Epson Corporation PX-105] was used for printing.

<Method for evaluating blocking resistance>
After printing water-based ink over the entire surface of a resin film using an inkjet method, it was cut into 4cm x 8cm sections. The printed side of this sample was placed next to an unprocessed, unprinted film of the same size, and subjected to a pressure of 7kg/cm² at 50°C for 24 hours. The resistance to peeling of the printed surface and the resulting image were analyzed using image processing software [product name "WinROOF", version 5.5, manufactured by Mitani Corporation]. The area of the remaining image (SA) and the pressure area (SB) were determined, and the image retention rate was calculated using the following formula and evaluated according to the following criteria.
Survival rate (%) = 100 x SA/SB
5 points: No ink peeling was observed at all from the printed material, and there was no resistance when peeling it off.
4 points: No ink peeling was observed from the printed material, but there was resistance when peeling it off.
3 points: Some ink peeling was observed on the printed material, but it covered less than 10% of the total printed area.
Two points: Ink peeling occurred on more than 10% but less than 50% of the total printed area of the printed material.
1. Ink peeling occurred on more than 50% of the printed area.
A score of 3 or higher indicates a practical level of performance.

[Test method for boil resistance]
A water-based ink was applied to a surface-treated polyester film (PET) [Toyobo Co., Ltd.'s "Espet E-5102" (thickness 12 μm)] using a bar coater to a thickness of 2-3 μm in solid content. After drying at 40°C for 1 minute, a dry laminating adhesive [main agent: Polybond AY-651A, hardener: Polybond AY-651C (manufactured by Sanyo Chemical Industries)] was applied to the coated surface, and it was bonded to LLDPE (manufactured by Mitsui Chemicals Tohcello Co., Ltd.) using a laminator, and aged at 40°C for 48 hours. Subsequently, the LLDPE side was heat-sealed to form a bag, and a mixture of vinegar, salad oil, and meat sauce in a 1:1:1 (weight ratio) ratio was sealed inside. After boiling at 98°C for 1 hour, the image was analyzed using image processing software [product name "WinROOF", version 5.5, manufactured by Mitani Shoji Co., Ltd.] to determine the area of the remaining image (SC) and the area of the composite image (SD). The image retention rate was calculated using the following formula and evaluated according to the following criteria.
Survival rate (%) = 100 x SC/SD
5 points: Image retention rate of 90-100%
4 points: Image retention rate is 80-89%
3 points: Image retention rate is 70-79%
2 points: Image retention is 50-69%
1 point: Image retention rate is less than 50%

<Permeability of water-based inks>
100g of water-based ink was filtered using a reduced-pressure filtration method, and the amount of liquid that passed through the filter until it became clogged was measured and evaluated according to the following criteria. A larger amount of liquid passing through indicates that the nozzles are less likely to become clogged during printing, and stable printing is possible. Clogging is mainly caused by large particles or aggregates of pigment or resin particles due to insufficient dispersion stability.
Filter: MF-Millipore SMWP04700
Filtration pressure: 50 kPa
5 points: Liquid passing amount 100g
4 points: Liquid passing amount 80-99g
3 points: Liquid passing amount 50-79g
2 points: Liquid passing amount 10-49g
1 point: Fluid volume less than 10g

The resin aqueous dispersion of the present invention is suitable for use as an inkjet ink and is useful as an ink raw material for printing using recording media such as resin media such as polycarbonate, rigid PVC, flexible PVC, polystyrene, expanded polystyrene, polymethyl methacrylate, polypropylene, polyethylene, and polyethylene terephthalate, paper media such as fine paper, art paper, coated paper, and cast coated paper, and metal media such as glass and stainless steel. In particular, it is suitable for flexible packaging using polypropylene (OPP) or polyethylene terephthalate (PET) as recording media.

Claims (2)

A resin aqueous dispersion (Q) containing a resin (P) having a constituent unit represented by general formula (1).
[In general formula (1), R1 is an aliphatic alkylene group having 11 to 64 carbon atoms, R2 is an aliphatic alkylene group having 1 to 6 carbon atoms, X is an amide group, and Y is an ester group or a urethane group. When Y is an ester group, the average number of repeating units of the constituent units represented by general formula (1) is 2 or more .] Aqueous ink (L) comprising the resin aqueous dispersion described in claim 1.