JP7596082B2 - Polyurethane urea resin solution and paints, printing inks, coating agents and adhesives using the same - Google Patents

Description

The present invention relates to a polyurethane urea resin solution and paints, printing inks, coating agents, and adhesives that use the same.

Conventionally, polyurethane resins have been used in the fields of paints, printing inks, adhesives (binders), and coating agents due to their excellent durability, chemical resistance, and abrasion resistance. In particular, polyurethane resins have excellent adhesion to substrates such as polyester and nylon, and solvent solutions of polyurethane resins are widely used from the viewpoint of handling and drying. However, polyurethane resins do not have sufficient adhesion to polyolefin substrates such as polyethylene and polypropylene, and chlorinated polyolefin resins are widely used instead for polyolefin substrates. However, chlorinated polyolefin resins do not have sufficient adhesion to substrates such as polyester and nylon, so there is a problem that the substrates to which they can be applied are limited.
For the purpose of improving the adhesive strength of polyester, nylon and polyolefin to substrates and for general use with various plastics, it has been proposed to use a mixture of polyurethane and chlorinated polyolefin (see, for example, Patent Document 1) or a urethane-modified product of oxidized chlorinated polyolefin as a binder (see, for example, Patent Document 2). Also, a method of improving adhesive strength by subjecting the substrate surface to a corona treatment or plasma treatment has been proposed (see, for example, Patent Document 3).

However, in recent years, attention has been focused on environmental issues, and there is a strong demand for suppressing the generation of harmful substances in the waste disposal of used products. The chlorinated polyolefins used in Patent Documents 1 and 2 contain chlorine, and therefore may generate harmful substances during incineration, which may pollute the environment.
Furthermore, in the method of subjecting the surface of the substrate to a corona treatment or plasma treatment, there is a problem in that the adhesiveness decreases with the lapse of time after the treatment.
Furthermore, toluene is widely used as a solvent for paints, printing inks, adhesives, and coating agents. However, the revision of the Industrial Safety and Health Act has strengthened the regulation of the environmental concentration of toluene, and the demand for solvent systems that do not contain toluene has increased, and more recently, there has been an increasing demand for alcohol-based solvent systems that are more environmentally friendly.

Japanese Patent Application Publication No. 10-251594 Japanese Patent Application Publication No. 11-323236 JP 2000-319426 A

The present invention has been made in consideration of the above problems, and aims to provide a polyurethane urea resin solution that does not contain harmful substances such as chlorine and toluene, does not impair mechanical strength, exhibits particularly excellent adhesion to plastic substrates (polyolefin, polyester, nylon, etc.) that have not been corona-treated or plasma-treated, and has excellent solution stability, as well as paints, printing inks, coating agents, and adhesives that use the same.

The inventors of the present invention have made extensive research to achieve the above object, and have arrived at the present invention. That is, the present invention is a polyurethane urea resin solution containing a polyurethane urea resin (U) having essential constituent monomers of hydroxyl-modified polyolefin (A), polyisocyanate (B), and a chain extender (C) having a number average molecular weight or chemical formula weight of less than 500, and a solvent (S), in which the weight ratio (ethylene:α-olefin) of the constituent monomers of the hydroxyl-modified polyolefin (A) to an α-olefin having 3 to 8 carbon atoms is 5:95 to 95:5, the isotacticity of the α-olefin unit chain of the hydroxyl-modified polyolefin (A) is 1 to 50%, and the number average molecular weight of the hydroxyl-modified polyolefin (A) is 1,000 to 6,000; and a paint, printing ink, coating agent, and adhesive containing the polyurethane urea resin solution.

The polyurethane urea resin solution of the present invention and the paints, printing inks, coating agents and adhesives using the same do not contain harmful substances such as chlorine and toluene, do not impair mechanical strength, and exhibit particularly excellent adhesion to plastic (polyolefin, polyester, nylon, etc.) substrates that have not been corona-treated or plasma-treated, and have excellent solution stability.

The polyurethane urea resin solution of the present invention contains a polyurethane urea resin (U) having, as essential constituent monomers, a hydroxyl group-modified polyolefin (A), a polyisocyanate (B), and a chain extender (C) having a number average molecular weight or chemical formula weight of less than 500, and a solvent (S).

<Polyurethane urea resin (U)>
In the present invention, the polyurethane urea resin (U) contains a hydroxyl group-modified polyolefin (A), a polyisocyanate (B), and a chain extender (C) having a number average molecular weight or chemical formula weight of less than 500 as essential constituent monomers.
In the present invention, the weight ratio (ethylene:α-olefin) of the constituent monomers of the hydroxyl-modified polyolefin (A) between ethylene and an α-olefin having 3 to 8 carbon atoms is 5:95 to 95:5, the isotacticity of the α-olefin unit chain of the hydroxyl-modified polyolefin (A) is 1 to 50%, and the number average molecular weight of the hydroxyl-modified polyolefin (A) is 1,000 to 6,000.
In the present invention, by using as (A) a resin having an appropriate amount of α-olefin structure, a number average molecular weight within the above range, and an isotacticity within the above range, it is possible to provide the molecular structure of the polyurethane urea resin (U) with a portion having high affinity for plastics in appropriate units while making the molecular structure of (U) low in crystallinity, and therefore it is presumed that it is possible to achieve both adhesion to plastics and solubility in solvents.

Hydroxyl-modified polyolefin (A) can be obtained by reacting an acid-modified polyolefin (X), which is a polyolefin (A1) having a carbon-carbon double bond modified with an unsaturated (poly)carboxylic acid (anhydride) (E), with an amino alcohol (G). It can also be obtained by reacting the acid-modified polyolefin (X) with an alkylene oxide.

The polyolefin (A1) having a carbon-carbon double bond in the present invention contains ethylene and an α-olefin having 3 to 8 carbon atoms as constituent monomers.
Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene. Although two or more types of α-olefins may be used in combination, it is preferable to use one type. Among the above α-olefins, propylene is preferable from the viewpoints of mechanical strength and productivity.

The weight ratio of ethylene, which is a constituent monomer of the polyolefin (A1) having a carbon-carbon double bond, to an α-olefin having 3 to 8 carbon atoms (ethylene:α-olefin) is 5:95 to 95:5, preferably 10:90 to 60:40, and more preferably 15:85 to 40:60.
If the weight ratio (ethylene:α-olefin) is less than 5:95, the adhesiveness is poor, whereas if it exceeds 95:5, the mechanical strength is poor.
The weight ratio (ethylene:α-olefin) can be calculated, for example, by ¹ H-MNR.

The (A1) may contain, as a constituent monomer, another monomer other than ethylene and an α-olefin having 3 to 8 carbon atoms. In that case, the weight of the other monomer is preferably 10% by weight or less, more preferably 5% by weight or less, and particularly preferably 1% by weight or less, based on the weight of all the monomers constituting (A1).
Examples of the other monomers include α-olefins having a carbon number (sometimes abbreviated as C) of 9 to 30 (1-decene, 1-dodecene, etc.), and unsaturated monomers having a carbon number of 4 to 30 other than α-olefins (for example, olefins such as 2-butene and isobutene, and vinyl monomers such as styrene, acrylonitrile, acrylamide, and vinyl acetate).

The number average molecular weight (hereinafter abbreviated as Mn) of the polyolefin (A1) having a carbon-carbon double bond is preferably 800 to 5,800, more preferably 800 to 3,800, from the viewpoints of adhesiveness, mechanical strength, and solvent solubility.

In the present invention, Mn is measured by GPC (gel permeation chromatography) under the following conditions.
Apparatus: High temperature gel permeation chromatograph
["Alliance GPC V2000", manufactured by Waters Corporation]
Detector: Refractive index detector Solvent: Orthodichlorobenzene Reference material: Polystyrene Sample concentration: 3 mg/ml
Column stationary phase: PLgel 10 μm, MIXED-B 2 columns in series
[Manufactured by Polymer Laboratories, Inc.]
Column temperature: 135°C

The number of double bonds in the polyolefin (A1) having a carbon-carbon double bond [the number of carbon-carbon double bonds at the molecular terminals and in the molecular chain of (A1)] per 1,000 carbon atoms is preferably 3 to 30, and more preferably 4 to 20, from the viewpoints of reactivity with the unsaturated (poly)carboxylic acid (anhydride) (E) described below and productivity.
The number of double bonds can be determined from the spectrum of (A1) by ¹ H-NMR (nuclear magnetic resonance) spectroscopy. That is, the peaks in the spectrum are assigned, and the relative value between the number of double bonds in (A1) and the number of carbon atoms in (A1) is determined from the integral value derived from the double bonds in (A1) at 4.5 to 6 ppm and the integral value derived from (A1), and the number of double bonds per 1,000 carbons in (A1) is calculated. The number of double bonds in the examples described below was determined according to the above method.

From the viewpoint of adhesion and solvent solubility, the isotacticity of the α-olefin unit chain portion of polyolefin (A1) having carbon-carbon double bonds is preferably 1 to 50%, and more preferably 5 to 45%. The isotacticity of the α-olefin unit chain portion of polyolefin (A1) tends to be directly reflected in the isotacticity of the α-olefin unit chain portion of the acid-modified polyolefin (X) and hydroxyl-modified polyolefin (A) described below. In addition, the isotacticity of the α-olefin unit chain portion of polyolefin (A1) having carbon-carbon double bonds tends to be reflected in the isotacticity of the α-olefin unit chain portion of the raw material polyolefin (A0) described below, so it can be adjusted by the raw material polyolefin (A0) used.

The isotacticity of the α-olefin unit sequence in the present invention can be calculated, for example, by ¹³ C-NMR (nuclear magnetic resonance spectroscopy). It is generally known that a side chain methyl group is influenced by the configuration (meso or racemo) with the methyl groups on both sides (triad), on both sides of the triad (pentad), and on both sides of the pentad (heptad), and peaks are observed at different chemical shifts. The stereoregularity is generally evaluated for the pentad, and the isotacticity in the present invention can also be calculated based on the evaluation of the pentad.
That is, when the α-olefin is propylene, the carbon peaks derived from the side chain methyl groups in the propylene obtained by ^13C -NMR are taken as the peaks of each pentad (H), and the peaks derived from the methyl groups in the isotactic propylene in which the pentad is formed only of a meso structure (Ha), the isotacticity is calculated by the following formula:
Isotacticity (%) = [(Ha) / Σ(H)] × 100 (1)
In the formula, H a is the peak height of an isotactic signal (pentads are formed only in the mesostructure), and H is the height of each peak of the pentad.

In the present invention, a method for producing polyolefin (A1) having a carbon-carbon double bond includes, for example, thermal degradation of polyolefin (A0) having a high molecular weight (preferably Mn of 60,000 to 400,000, more preferably Mn of 80,000 to 250,000).

The thermal degradation method includes a method in which the high molecular weight polyolefin (A0) is thermally degraded (1) in the absence of an organic peroxide, for example, at 300 to 450° C. for 0.5 to 10 hours, and (2) in the presence of an organic peroxide [for example, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane], for example, at 180 to 300° C. for 0.5 to 10 hours.
Of these, the method (1) is preferred from the industrial viewpoint and from the viewpoint of modification properties, since it is easy to obtain a polymer having a larger number of double bonds at the molecular terminals and/or in the molecular chain.

The weight ratio [ethylene:α-olefin] of ethylene and α-olefin (having 3 to 8 carbon atoms), which are monomers constituting the above (A1), tends to be maintained the same as the weight ratio [ethylene:α-olefin] of the high molecular weight polyolefin (A0).
The higher the thermal degradation temperature and the longer the thermal degradation time, the greater the number of double bonds per 1,000 carbon atoms tends to be.
Furthermore, the smaller the Mn of (A0), the higher the thermal degradation temperature, and the longer the thermal degradation time, the smaller the Mn of (A1) tends to be.

The unsaturated (poly)carboxylic acid (anhydride) (E) in the present invention may, for example, be a C3-30 (poly)carboxylic acid (anhydride) having one polymerizable unsaturated group.
In the present invention, the unsaturated (poly)carboxylic acid (anhydride) means an unsaturated monocarboxylic acid, an unsaturated polycarboxylic acid and/or an unsaturated polycarboxylic acid anhydride.
Examples of the unsaturated monocarboxylic acid include aliphatic unsaturated monocarboxylic acids (C3-24, for example, acrylic acid, methacrylic acid, α-ethylacrylic acid, crotonic acid, isocrotonic acid) and alicyclic-containing unsaturated monocarboxylic acids (C6-24, for example, cyclohexene carboxylic acid).
Examples of the unsaturated poly(2-3 or more) carboxylic acid (anhydride) include unsaturated dicarboxylic acid (anhydride) [aliphatic dicarboxylic acid (anhydride) (C4-24, for example, maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, and anhydrides thereof) and alicyclic ring-containing dicarboxylic acid (anhydride) (C8-24, for example, cyclohexene dicarboxylic acid, cycloheptene dicarboxylic acid, bicycloheptene dicarboxylic acid, methyltetrahydrophthalic acid, and anhydrides thereof)].
(E) may be used alone or in combination of two or more kinds.
Among the (E) compounds, from the viewpoint of reactivity with the polyolefin (A1), unsaturated dicarboxylic acid anhydrides are preferred, and maleic anhydride is more preferred.

The acid-modified polyolefin (X) contains the polyolefin (A1) having a carbon-carbon double bond and an unsaturated (poly)carboxylic acid (anhydride) (E) as constituent monomers.
The weight ratio of the constituent monomers (A1) and (E) in the acid-modified polyolefin (X) [(A1):(E)] is preferably 80:20 to 99.5:0.5, more preferably 90:10 to 99:1, from the viewpoint of the balance between mechanical strength and adhesiveness.

The acid-modified polyolefin (X) can be preferably produced by reacting a polyolefin (A1) and an unsaturated (poly)carboxylic acid (anhydride) (E) in the presence of a radical initiator (F), if necessary, in a suitable organic solvent [C3 to C18, for example, hydrocarbons (hexane, heptane, octane, dodecane, benzene, toluene, xylene, etc.), halogenated hydrocarbons (di-, tri-, or tetrachloroethane, dichlorobutane, etc.), ketones (acetone, methyl ethyl ketone, di-t-butyl ketone, etc.), and ethers (ethyl-n-propyl ether, di-n-butyl ether, di-t-butyl ether, dioxane, etc.)].
The radical initiator (F) may be any known initiator, such as an azo initiator (azobisisobutyronitrile, etc.) or a peroxide initiator (dicumyl peroxide, etc.), with the peroxide initiator being preferred.

From the viewpoints of reactivity between (A1) and (E) and productivity, the reaction temperature is preferably 100 to 270°C, more preferably 120 to 250°C, and particularly preferably 130 to 240°C.

The acid value of the acid-modified polyolefin (X) is preferably 1 to 100 mgKOH/g, more preferably 3 to 75 mgKOH/g, and particularly preferably 5 to 50 mgKOH/g, from the viewpoint of the solvent solubility and adhesiveness of the polyurethane urea resin (U). The acid value here is a value measured according to the following procedures (i) to (iii) in accordance with JIS K0070:1992.
(i) 1 g of (X) is dissolved in 100 g of xylene adjusted to 100° C.
(ii) At the same temperature, titration is performed with a 0.1 mol/L ethanolic potassium hydroxide solution [product name "0.1 mol/L ethanolic potassium hydroxide solution", manufactured by Wako Pure Chemical Industries, Ltd.] using phenolphthalein as an indicator.
(iii) The amount of potassium hydroxide required for the titration is converted into mg to calculate the acid value (unit: mgKOH/g).
In the above measurement, one acid anhydride group is equivalent to one carboxyl group.
The acid value can be appropriately adjusted by the number of double bonds in (A1), the weight of (A1), the type of (E), and the weight of (E).

From the viewpoint of the solvent solubility and adhesiveness of the polyurethane urea resin (U), the Mn of the acid-modified polyolefin (X) is preferably 900 to 5,900, more preferably 900 to 5,000, and particularly preferably 900 to 4,000.

The isotacticity of the α-olefin unit chain of the acid-modified polyolefin (X) is preferably 1 to 50%, more preferably 5 to 45%, and particularly preferably 10 to 40%, from the viewpoints of the solvent solubility, adhesiveness, and mechanical strength of the polyurethane urea resin (U).

Examples of the hydroxyl-modified polyolefin (A) in the present invention include a reaction product of the acid-modified polyolefin (X) with an aminoalcohol (G) and a reaction product of the acid-modified polyolefin (X) with an alkylene oxide (hereinafter abbreviated as AO).

Examples of amino alcohols (G) include linear alkanolamines, cycloalkanolamines and alkyl alkanolamines having 2 to 12 carbon atoms (e.g., 2-aminoethanol, 3-aminopropanol, 1-amino-2-propanol, 2-amino-2-methyl-1-propanol, 4-aminobutanol, 5-aminopentanol, 6-aminohexanol, diethanolamine, di-n- or isopropanolamine, 3-aminomethyl-3,5,5-trimethylcyclohexanol, methylethanolamine and ethylethanolamine), with 2-aminoethanol being preferred.

Examples of AO include AOs having a carbon number of 2 to 12 (ethylene oxide, 1,2- or 1,3-propylene oxide, 1,2-, 2,3- or 1,3-butylene oxide, tetrahydrofuran, 3-methyltetrahydrofuran, styrene oxide, α-olefin oxide, etc.), preferably those having a carbon number of 2 to 4, and more preferably ethylene oxide and propylene oxide. AOs may be used alone or in combination of two or more.
The number of moles of AO added is preferably 1 to 10 moles or more, more preferably 1 to 5 moles, and particularly preferably 1 mole, per carboxyl group of the acid-modified polyolefin (X).

The modification of the acid-modified polyolefin (X) with the aminoalcohol (G) can be carried out by a known method, for example, by adding an excess (for example, 1.1 to 2 times or more moles) of aminoalcohol to the carboxyl group (carbonyl group in the case of anhydride) of the acid-modified polyolefin (X) to react with it, and then removing the unreacted aminoalcohol by a method such as distillation. The reaction can be carried out in the presence or absence of an organic solvent. The reaction temperature is preferably 100 to 220°C, more preferably 120 to 200°C.
The modification of the acid-modified polyolefin (X) with AO is carried out by a known method. For example, the reaction temperature when the AO is subjected to ring-opening addition polymerization is preferably 40 to 200° C., more preferably 70 to 160° C. The reaction pressure is preferably −0.1 to 0.5 MPa. The reaction is carried out in the presence of a catalyst as necessary.

The weight ratio of ethylene and an α-olefin having 3 to 8 carbon atoms (ethylene:α-olefin), which are constituent monomers of the hydroxyl group-modified polyolefin (A), is 5:95 to 95:5, preferably 10:90 to 60:40, and more preferably 15:85 to 40:60.
If the weight ratio (ethylene:α-olefin) is less than 5:95, the adhesiveness is poor, whereas if it exceeds 95:5, the mechanical strength is poor.
The weight ratio of ethylene and the α-olefin having 3 to 8 carbon atoms, which are the constituent monomers of the hydroxyl group-modified polyolefin (A), can be appropriately adjusted by the ratio of ethylene and the α-olefin having 3 to 8 carbon atoms used in (A0).

The isotacticity of the α-olefin unit chain of the hydroxyl group-modified polyolefin (A) is 1 to 50%, preferably 5 to 45%. If the isotacticity is less than 1%, the adhesiveness is poor, and if it exceeds 50%, the solvent solubility is poor.
The isotacticity of the α-olefin unit sequence of (A) can be appropriately adjusted by the isotacticity of (A0).

The Mn of the hydroxyl-modified polyolefin (A) is from 1,000 to 6,000, preferably from 1,000 to 4,000, from the viewpoints of adhesiveness and solvent solubility.
The Mn of (A) can be appropriately adjusted by controlling the Mn of (A1), the type and amount of (E) used, and the reaction between (A1) and (E).

The hydroxyl value (mgKOH/g) of the hydroxyl-modified polyolefin (A) is preferably 14 to 110, preferably 20 to 100, and more preferably 25 to 80. When the hydroxyl value is 14 or more, the solvent solubility of the polyurethane urea resin (U) tends to be good, and when it is 110 or less, the adhesion of (U) to a polyolefin film tends to be good.
The hydroxyl value of (A) can be appropriately adjusted by the number of double bonds in (A1), the amount of (A1) used, and the type and amount of (E) used.
The acid value (mgKOH/g) of (A) is preferably 0 to 10, and more preferably 0 to 5.
The hydroxyl value and acid value of (A) are values measured in accordance with JIS K0070-1992.

In the present invention, the number of hydroxyl groups per molecule of the hydroxyl-modified polyolefin (A) is preferably 1.5 to 2.0, more preferably 1.6 to 2.0, from the viewpoints of the solvent solubility, adhesiveness and mechanical strength of the polyurethane urea resin (U). The number of hydroxyl groups per molecule of the hydroxyl-modified polyolefin (A) can be calculated by the following mathematical formula (1).
Number of hydroxyl groups per molecule = _MnA x OHV/56100 (1)
_MnA : Mn of (A)
OHV: hydroxyl value of (A) (mg KOH/g)

When the polyurethane urea resin (U) uses multiple types of hydroxyl-modified polyolefins (A), the weight average number of hydroxyl groups in all of the hydroxyl-modified polyolefins (A) constituting the polyurethane urea resin (U) is preferably 1.5 to 2.0, and more preferably 1.6 to 2.0, from the viewpoints of the solvent solubility, adhesiveness, and mechanical strength of the polyurethane urea resin (U).

The polyurethane urea resin (U) in the present invention contains a hydroxyl group-modified polyolefin (A) as an essential constituent monomer. (A) may be used alone or in combination of two or more types.

The polyurethane urea resin (U) can further contain, in combination with a polyol component, at least one polyol (H) selected from the group consisting of condensation type polyester polyols (H1), polylactone polyols (H2), polycarbonate polyols (H3), polyether polyols (H4) and poly(meth)acrylic polyols (H5).
From the viewpoint of solvent solubility, the hydroxyl value (mgKOH/g) of the polyol (H) is preferably from 22 to 225, more preferably from 28 to 113. The hydroxyl value of (H) is a value measured in accordance with JIS K0070-1992.

The Mn of the polyol (H) is preferably from 500 to 5,000, and more preferably from 1,000 to 4,000, from the viewpoint of solvent solubility.
The number average molecular weight (Mn) of the polyol (H) in the present invention can be measured by gel permeation chromatography (GPC) under the following conditions, for example.
Apparatus: "Waters Alliance 2695" [manufactured by Waters]
Column: "Guardcolumn Super H-L" (1 column), "TSKgel
One each of Super H2000, TSKgel Super H3000, and TSKgel Super H4000 (all manufactured by Tosoh Corporation) connected together.
Sample solution: 0.25% by weight tetrahydrofuran solution Solution injection amount: 10 μl
Flow rate: 0.6ml/min Measurement temperature: 40℃
Detector: Refractive index detector Reference material: Standard polyethylene glycol

Examples of condensation type polyester polyols (H1) include those obtained by condensing a diol having an Mn of less than 500 with a dicarboxylic acid or an ester-forming derivative thereof [such as an acid anhydride, a lower (carbon number 1 to 4) alkyl ester, and an acid halide].

Diols with Mn less than 500 include aliphatic dihydric alcohols having 2 to 8 carbon atoms [linear diols (ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, etc.) and diols having branched alkyl chains (1,2-propanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 1,2-, 1,3- or 2,3-butanediol, etc.)]; Examples of the dihydric alcohols include alicyclic group-containing dihydric alcohols [such as 1,4-bis(hydroxymethyl)cyclohexane and 2,2-bis(4-hydroxycyclohexyl)propane]; aromatic ring-containing dihydric alcohols having 8 to 20 carbon atoms [m- or p-xylylene glycol, bis(hydroxyethyl)benzene, bis(hydroxyethoxy)benzene]; AO adducts of bisphenols (such as bisphenol A, bisphenol S, and bisphenol F), AO adducts of dihydroxynaphthalene, and bis(2-hydroxyethyl)terephthalate]. Diols having an Mn of less than 500 may be used alone or in combination of two or more.

Examples of dicarboxylic acids or their ester-forming derivatives include aliphatic dicarboxylic acids having 2 to 15 carbon atoms [oxalic acid, succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid, maleic acid, fumaric acid, etc.], aromatic dicarboxylic acids having 8 to 12 carbon atoms [terephthalic acid, isophthalic acid, etc.], and their ester-forming derivatives [acid anhydrides, lower alkyl esters (dimethyl esters, diethyl esters, etc.), acid halides (acid chlorides, etc.)]. One type of dicarboxylic acid may be used alone, or two or more types may be used in combination.

Specific examples of condensation type polyester polyols (H1) include polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polyhexamethylene isophthalate diol, polyneopentyl adipate diol, polyethylene propylene adipate diol, polyethylene butylene adipate diol, polybutylene hexamethylene adipate diol, poly(polyoxytetramethylene) adipate diol, poly(3-methylpentylene adipate) diol, polyethylene azelate diol, polyethylene sebacate diol, polybutylene azelate diol, polybutylene sebacate diol, and polyneopentyl terephthalate diol.

Of the condensation type polyester polyols (H1), from the viewpoint of adhesion and solvent solubility, polyester diols having branched alkyl chains are preferred, polyneopentyl adipate diol and poly(3-methylpentylene adipate) diol are particularly preferred, and poly(3-methylpentylene adipate) diol is most preferred. (H1) may be used alone or in combination of two or more types.

Examples of polylactone polyols (H2) include those obtained by ring-opening polymerization of lactone monomers (such as γ-butyrolactone, γ-valerolactone, ε-caprolactone, and mixtures of two or more of these) using the above-mentioned diol having an Mn of less than 500 as an initiator. Specific examples of polylactone polyols (H2) include polybutyrolactone diol, polyvalerolactone diol, and polycaprolactone diol. (H2) may be used alone or in combination of two or more.

Examples of polycarbonate polyols (H3) include polycarbonate diols produced by condensing the diol having an Mn of less than 500 with a low molecular weight carbonate compound (for example, a dialkyl carbonate having an alkyl group with 1 to 6 carbon atoms, an alkylene carbonate having an alkylene group with 2 to 6 carbon atoms, and a diaryl carbonate having an aryl group with 6 to 9 carbon atoms) while causing a dealcoholization reaction. (H3) may be used alone or in combination of two or more types.

Specific examples of polycarbonate polyols (H3) include polyhexamethylene carbonate diol, polypentamethylene carbonate diol, polytetramethylene carbonate diol, and poly(tetramethylene/hexamethylene) carbonate diol (e.g., a diol obtained by condensing 1,4-butanediol and 1,6-hexanediol with a dialkyl carbonate while causing a dealcoholization reaction).

The polyether polyol (H4) may be an adduct of the above-mentioned AO having 2 to 12 carbon atoms to a diol having an Mn of less than 500, and the AO may be used alone or in the form of block copolymer or random copolymer of two or more kinds.

Among the polyether polyols (H4), those having branched alkyl chains are preferred from the viewpoint of solvent solubility, i.e., those using as the raw material a diol having a branched alkyl chain among diols with Mn of less than 500, and those using 1,2-propylene oxide, 1,2-, 2,3- or 1,3-butylene oxide, 3-methyltetrahydrofuran, etc. as the AO in the AO adduct, and more preferred are aliphatic polyether diols of dihydric alcohols having branched alkyl, and particularly preferred is polyoxypropylene glycol. (H4) may be used alone or in combination of two or more types.

Examples of the poly(meth)acrylic polyol (H5) include homopolymers and copolymers of (meth)acrylic acid esters having a hydroxyl group. The (meth)acrylic polyol can also be obtained by copolymerizing a compound having a polymerizable unsaturated bond in addition to the (meth)acrylic acid ester having a hydroxyl group.
In the present invention, "(meth)acrylic" means "methacrylic and/or acrylic".

The (meth)acrylic acid esters having a hydroxy group include those having one (meth)acryloyl group, such as those having a hydroxyalkyl group having 2 to 20 carbon atoms (e.g., hydroxyalkyl (meth)acrylic acid esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate), and (meth)acrylic acid monoesters of trihydric alcohols (e.g., (meth)acrylic acid monoesters of glycerin, (meth)acrylic acid monoesters of trimethylolpropane, etc.).

The compound having a polymerizable unsaturated bond includes compounds having one polymerizable unsaturated bond, such as (meth)acrylic acid alkyl esters having 4 to 50 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, lauryl (meth)acrylate, glycidyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate; unsaturated carboxylic acids having 3 to 50 carbon atoms, such as (meth)acrylic acid, maleic acid, and itaconic acid; unsaturated amides having 3 to 50 carbon atoms, such as (meth)acrylamide, N-methylol (meth)acrylamide, and diacetone (meth)acrylamide; and other polymerizable monomers, such as styrene, vinyl toluene, vinyl acetate, acrylonitrile, and dibutyl fumarate.

Examples of the polymerization method for the (meth)acrylic acid ester having a hydroxy group or the compound having a polymerizable unsaturated bond include emulsion polymerization, suspension polymerization, dispersion polymerization, and solution polymerization. The emulsion polymerization can also be carried out in stages.

Specific examples of the commercially available poly(meth)acrylic polyol (H5) include "ARUFON UH-2000, UH-2041, UH-2190, UHE-2012" manufactured by Toagosei Co., Ltd., and "Actflow UT-1001, UMM-1001" manufactured by Soken Chemical & Engineering Co., Ltd.

Among the poly(meth)acrylic polyols (H5), from the viewpoint of solvent solubility, it is preferable to use at least one compound having a polymerizable unsaturated bond selected from the group consisting of n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, lauryl (meth)acrylate, and 2-ethylhexyl (meth)acrylate, and more preferably a polyacrylic diol using n-butyl (meth)acrylate and/or 2-ethylhexyl (meth)acrylate. (H5) may be used alone or in combination of two or more kinds.

When the hydroxyl-modified polyolefin (A) is used in combination with at least one selected from the group consisting of condensation type polyester polyol (H1), polylactone polyol (H2), polycarbonate polyol (H3), polyether polyol (H4) and poly(meth)acrylic polyol (H5), the ratio of the total weight of the condensation type polyester polyol (H1), polylactone polyol (H2), polycarbonate polyol (H3), polyether polyol (H4) and poly(meth)acrylic polyol (H5) to the weight of the hydroxyl-modified polyolefin (A) is preferably 100% by weight or less, more preferably 10 to 90% by weight, from the viewpoint of the solvent solubility and mechanical strength of the polyurethane urea resin (U).

The polyisocyanate (B) in the present invention may include aliphatic diisocyanates (B1) having 4 to 22 carbon atoms, alicyclic diisocyanates (B2) having 8 to 18 carbon atoms, aromatic diisocyanates (B3) having 8 to 26 carbon atoms, and aromatic aliphatic diisocyanates (B4) having 10 to 18 carbon atoms.

Examples of aliphatic diisocyanates (B1) having 4 to 22 carbon atoms include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl caproate, bis(2-isocyanatoethyl) fumarate, and bis(2-isocyanatoethyl) carbonate.

Examples of alicyclic diisocyanates (B2) having 8 to 18 carbon atoms include isophorone diisocyanate (hereinafter abbreviated as IPDI), 4,4-dicyclohexylmethane diisocyanate, cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, bis(2-isocyanatoethyl)-4-cyclohexene-1,2-dicarboxylate, and 2,5- or 2,6-norbornane diisocyanate.

Examples of aromatic diisocyanates (B3) having 8 to 26 carbon atoms include 1,3- or 1,4-phenylene diisocyanate, 2,4- or 2,6-tolylene diisocyanate, 4,4'- or 2,4'-diphenylmethane diisocyanate, polyaryl diisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, and m- or p-isocyanatophenylsulfonyl isocyanate.

Examples of aromatic aliphatic diisocyanates (B4) having 10 to 18 carbon atoms include m- or p-xylylene diisocyanate and α,α,α',α'-tetramethylxylylene diisocyanate.

Among these, from the viewpoint of adhesiveness, preferred is the alicyclic diisocyanate having 8 to 18 carbon atoms (B2), and further preferred from the viewpoints of the solvent solubility and adhesiveness of the polyurethane urea resin (U) is IPDI.
The polyisocyanate (B) may be used alone or in combination of two or more kinds.

In the present invention, examples of the chain extender (C) having an Mn or formula weight of less than 500 include polyamine (C1) and polyol (C2). (C) may be used alone or in combination of two or more types.

Examples of the polyamine (C1) include diamines having 2 to 12 carbon atoms (ethylene diamine, propylene diamine, hexamethylene diamine, isophorone diamine, toluene diamine, piperazine, etc.), poly(n=2-6) alkylene (having 2-6 carbon atoms) poly(n=3-7) amines (diethylene triamine, dipropylene triamine, dihexylene triamine, triethylene tetramine, tetraethylene pentamine, pentaethylene hexamine, hexaethylene heptamine, etc.), and hydrazine or a derivative thereof (dibasic acid dihydrazide, for example, adipic acid dihydrazide, etc.).
Among these, from the viewpoints of adhesion and solvent solubility, alicyclic diamines are preferred, and isophorone diamine is more preferred.

Examples of polyols (C2) include those exemplified above as diols with an Mn of less than 500, with 1,4-butanediol being preferred from the standpoint of adhesion and solvent solubility.

When obtaining polyurethane urea resin (U), in addition to the essential components (A), (B), and (C), a reaction terminator (D) can be used to adjust the molecular weight of the polyurethane urea resin.

Examples of reaction stoppers (D) include monoalcohols having 1 to 10 carbon atoms (methanol, propanol, butanol, 2-ethylhexanol, etc.) and monoamines having 2 to 8 carbon atoms [mono- or di-alkylamines having 2 to 8 carbon atoms (n-butylamine, di-n-butylamine, etc.), mono- or dialkanolamines having 2 to 6 carbon atoms (monoethanolamine, diethanolamine, propanolamine, etc.)]. Among these, mono- or dialkanolamines having 2 to 6 carbon atoms are preferred. One type of reaction stopper (D) may be used alone, or two or more types may be used in combination.

The amine value of the polyurethane urea resin (U) is preferably 0.1 to 20 mgKOH/g, more preferably 0.1 to 5 mgKOH/g, and particularly preferably 0.2 to 2 mgKOH/g. When the amine value is 0.1 mgKOH/g or more, the adhesiveness is good, and when it is 20 mgKOH/g or less, the viscosity and molecular weight have good stability over time.

The weight ratio [{(A)+(H1)-(H5)}:(B):(C)] of the total amount of the hydroxyl-modified polyolefin (A) and the polyols (H1)-(H5) used as needed to the polyisocyanate (B) and the chain extender (C) in the polyurethane urea resin (U) is preferably 100:(10-40):(1-20), more preferably 100:(12-35):(2-18), from the viewpoints of the solvent solubility, adhesiveness and mechanical strength of the polyurethane urea resin (U).

The method for producing the polyurethane urea resin (U) is not particularly limited, and may be any of the following: a one-shot method in which the hydroxyl-modified polyolefin (A), polyisocyanate (B), chain extender (C), and, if necessary, polyol (H) and reaction terminator (D) are reacted at once, or a multi-stage method in which they are reacted in stages [for example, a method in which (A), (B), and, if necessary, (H) and (C) are reacted to form an isocyanate-terminated prepolymer, and then (C) and, if necessary, (D) are added and further reacted to produce the resin]. However, from the viewpoint of adhesion, a method in which an isocyanate-terminated prepolymer is formed, and then an amino group is introduced to the end of the polyurethane urea molecular chain using a diamine having 2 to 12 carbon atoms as the chain extender (C) such that the total value of the amino groups in the diamine is in excess relative to the equivalent weight of the isocyanate groups in the prepolymer is preferred.

In producing the polyurethane urea resin (U), the molar ratio (isocyanate group:active hydrogen-containing group) of the isocyanate group of the polyisocyanate (B) to the active hydrogen-containing group of the hydroxyl group-modified polyolefin (A), the chain extender (C), and the polyol (H) and reaction terminator (D) used as necessary is preferably 0.7:1 to 0.99:1, more preferably 0.8:1 to 0.98:1, from the viewpoint of the solvent solubility and mechanical strength of the polyurethane urea resin (U).

The urethane group concentration of the polyurethane urea resin (U) in the present invention is preferably 0.4 to 1.5 mmol/g, and more preferably 0.6 to 1.0 mmol/g, based on the weight of (U), from the viewpoints of adhesiveness, mechanical strength, and solvent solubility.
The urea group concentration of the polyurethane urea resin (U) in the present invention is preferably 0.3 to 1.3 mmol/g, and more preferably 0.3 to 1.2 mmol/g, based on the weight of (U), from the viewpoints of adhesiveness, mechanical strength, and solvent solubility.
The total concentration of the urethane group and the urea group in the polyurethane urea resin (U) in the present invention is preferably 0.7 to 2.2 mmol/g, and more preferably 1.0 to 2.0 mmol/g, based on the weight of (U), from the viewpoints of adhesiveness, mechanical strength, and solvent solubility.
In order to adjust the urea group content in the polyurethane urea resin (U) to fall within a desired range, the amino group content, water content and isocyanate group content in the raw materials of (U) may be appropriately adjusted.
The urethane group concentration and urea group concentration in the polyurethane urea resin (U) can be calculated from the N atom content determined by a nitrogen analyzer and the ratio of the urethane group to the urea group, as well as the allophanate group and biuret group contents determined by ¹ H-NMR.

In the present invention, the urethane group concentration and the urea group concentration of the polyurethane urea resin (U) can be measured as follows.
(Urethane Group Concentration and Urea Group Concentration of Polyurethane Urea Resin (U))
The urethane group concentration and urea group concentration of the polyurethane urea resin (U) are calculated from the N atom content quantified by a nitrogen analyzer [ANTEK7000 (manufactured by Antec)], the ratio of the urethane group to the urea group quantified by ¹ H-NMR, and the allophanate group and biuret group contents described below.
The ¹ H-NMR measurement is carried out by the method described in "Structural Study of Polyurethane Resins by NMR: Takeda Laboratory Report 34(2), 224-323 (1975)". That is, when an aliphatic isocyanate is used by measuring ¹ H-NMR, the weight ratio of urea groups to urethane groups is measured from the ratio of the integral amount of hydrogen derived from urea groups at a chemical shift of about 6 ppm to the integral amount of hydrogen derived from urethane groups at a chemical shift of about 7 ppm, and the contents of urethane groups and urea groups are calculated from the weight ratio, the above-mentioned N atom content, and the allophanate group and biuret group contents.
When an aromatic isocyanate is used, the weight ratio of urea groups to urethane groups is calculated from the ratio of the integral amount of hydrogen derived from urea groups at a chemical shift of about 8 ppm to the integral amount of hydrogen derived from urethane groups at a chemical shift of about 9 ppm, and the contents of urethane groups and urea groups are calculated from this weight ratio, the above-mentioned N atom content, and the allophanate group and biuret group contents.

(Allophanate Group and Biuret Group Content)
The total content of allophanate groups and biuret groups in polyurethane urea resin (U) is calculated by gas chromatography [Shimadzu GC-9A {manufactured by Shimadzu Corporation}]. 50 g of DMF solution containing 0.01 wt% di-n-butylamine and 0.01 wt% naphthalene (internal standard) is prepared. A sample is weighed into a test tube with a stopper, 2 g of the above DMF solution is added, and the test tube is heated in a thermostatic water bath at 90°C for 2 hours. After cooling to room temperature, 10 μl of acetic anhydride is added and shaken and stirred for 10 minutes. Further, 50 μl of di-n-propylamine is added, and after shaking for 10 minutes, gas chromatographic measurement is performed. A blank measurement is performed in parallel, and the amount of amine consumed is calculated from the difference with the test value, and the total content of allophanate groups and biuret groups is measured.
(Gas chromatograph conditions)
Equipment: Shimadzu GC-9A
Column: 10% PEG-20M on Chromosorb WAW DMLS 60/80 mesh glass column 3 mmφ×2 m
Column temperature: 160°C, sample inlet temperature: 200°C, carrier gas: nitrogen 40 ml/min, detector: FID, sample injection amount: 2 μl
(Calculation formula for the total content of allophanate groups and biuret groups)
Total content of allophanate group and biuret group={(B−A)/B}×0.00155/S
A: (peak area of di-n-butylacetamide/peak area of naphthalene) of the sample
B: Blank (peak area of di-n-butylacetamide/peak area of naphthalene)
S: Amount of polyurethane urea resin (U) collected (g)

The reaction between the hydroxyl-modified polyolefin (A) and the polyisocyanate (B) is carried out at a temperature of preferably 20 to 140°C, more preferably 40 to 120°C.
The reaction temperature of the polyisocyanate (B) or the isocyanate-terminated prepolymer obtained by reacting the hydroxyl-modified polyolefin (A) with the polyisocyanate (B) with the chain extender (C) is preferably 100°C or lower, more preferably 0 to 80°C.

In the above reaction, in order to accelerate the reaction, catalysts generally used in urethane reactions [amine catalysts (triethylamine, N-ethylmorpholine, triethylenediamine, etc.), tin-based catalysts (dibutyltin dilaurate, dioctyltin dilaurate, tin octoate, etc.), and titanium-based catalysts (tetrabutyl titanate, etc.)] may be used as necessary. The amount of catalyst used is preferably 0.1% by weight or less relative to the polyurethane urea resin.

The reaction may be carried out in a solvent (S), and the solvent (S) may be added during or after the reaction.
Examples of the solvent (S) include ester-based solvents (ethyl acetate, butyl acetate, ethyl cellosolve acetate, etc.), ketone-based solvents (acetone, methyl isobutyl ketone, methyl isobutyl ketone, etc.), ether-based solvents (dioxane, tetrahydrofuran, propylene glycol monomethyl ether, etc.), aliphatic hydrocarbon-based solvents (n-hexane, n-heptane, cyclohexane, methylcyclohexane, etc.), and alcohol-based solvents (ethanol, methanol, n-propyl alcohol, isopropyl alcohol, n-butanol, etc.).

Among these, from the viewpoint of the solubility of the polyurethane urea resin (U), at least one selected from the group consisting of ethyl acetate, butyl acetate, propylene glycol monomethyl ether, methyl ethyl ketone, methyl isobutyl ketone, n-propyl alcohol, methylcyclohexane, and isopropyl alcohol is preferred, and at least one selected from the group consisting of ethyl acetate, methyl ethyl ketone, methylcyclohexane, and isopropyl alcohol is more preferred. The solvent (S) may be used alone or in combination of two or more.

The number average molecular weight (Mn) of the polyurethane urea resin (U) in the present invention is preferably 10,000 to 40,000. If Mn is 10,000 or more, the adhesiveness is good when using one liquid, and if Mn is 40,000 or less, the solubility and workability are good.

<Polyurethane urea resin solution>
The polyurethane urea resin solution of the present invention contains the polyurethane urea resin (U) and a solvent (S).
Examples of the solvent (S) include those mentioned above. From the viewpoint of the solubility of the polyurethane urea resin (U), preferred are ethyl acetate, propylene glycol monomethyl ether, methyl ethyl ketone, methylcyclohexane, n-propyl alcohol, and isopropyl alcohol, and more preferred are ethyl acetate, methyl ethyl ketone, methylcyclohexane, and isopropyl alcohol.

The content of the polyurethane urea resin (U) in the polyurethane urea resin solution of the present invention is preferably 10 to 50% by weight, more preferably 20 to 40% by weight, based on the weight of the polyurethane urea resin solution, from the viewpoint of handleability.
The polyurethane urea resin (U) in the polyurethane urea resin solution of the present invention has good mechanical strength and excellent adhesion to plastic (polyolefin, polyester, nylon, etc.) substrates, and the polyurethane urea resin solution of the present invention has excellent solution stability. Therefore, by using the polyurethane urea resin solution of the present invention, it is possible to obtain paints, printing inks, coating agents, and adhesives which have good mechanical strength, excellent adhesion to plastic substrates, and excellent solution stability.

<Paint>
The coating material of the present invention contains the polyurethane urea resin solution of the present invention. In the coating material of the present invention, the polyurethane urea resin (U) exhibits functions as a binder, a pigment dispersing resin, or the like.
The content of the polyurethane urea resin (U) of the present invention in the coating material of the present invention is preferably 1 to 40% by weight, more preferably 2 to 30% by weight, based on the weight of the coating material, from the viewpoints of adhesion, mechanical strength and handleability.

The coating material of the present invention may contain any of the additives commonly used in coating materials.
Examples of additives include pigments, curing agents, diluents, leveling agents such as acrylic resins and silicone resins, silicone-based and acrylic-based anti-repellents, anti-skinning agents, thixotropic agents, defoamers, color separation inhibitors, smoothing agents, wetting agents, dispersants, thickeners, anti-settling agents, polymerization inhibitors, structural viscosity imparting agents, electrostatic coating property improvers, sagging inhibitors, curing accelerators, antioxidants, light stabilizers, antifouling agents, flame retardants, coating aids, etc. Preferred examples of light stabilizers and antioxidants include the compounds described in JP-A-2004-117997.

The coating film formed by the paint can be applied to any thickness depending on the application, but the final coating film thickness is preferably 0.1 to 10,000 μm, more preferably 0.1 to 2,000 μm, even more preferably 1 to 1,000 μm, even more preferably 5 to 1,000 μm, and even more preferably 5 to 200 μm.
The coating method may be any method, including spraying, dipping, roller coating, flow coating, flow painting, electrocoating, powder flow painting, brush painting, and the like.
Drying after application varies depending on the paint components, but can be done by natural drying or heat drying (generally at room temperature to 180° C. for about 10 to 90 minutes).

The viscosity (20° C.) of the coating material of the present invention is preferably from 100 to 5,000 mPa·s, more preferably from 500 to 3,000 mPa·s, from the viewpoint of handleability.
The viscosity of the coating material can be measured using a B-type viscometer in accordance with JIS-K7117-1.

The coating material of the present invention can be applied to any substrate, such as metals (steel plates, iron and steel, non-ferrous metals, light metals, etc.), plastics (polyolefins, polyesters, nylons, etc.), wood, glass, concrete, resins, rubber, leather, paper, skin, etc., depending on the application, to form a coating film and produce a desired member, but from the viewpoint of adhesion, plastic substrates are preferred as substrates.
The coating material of the present invention can be used, for example, as an automotive coating material for automotive parts, automotive bumpers, and vehicle bodies, an electrical appliance coating material, an architectural coating material, an anti-rust coating material, and the like, and is particularly useful as an automotive coating material.

<Printing ink>
The printing ink of the present invention contains the polyurethane urea resin solution of the present invention. In the printing ink of the present invention, the polyurethane urea resin (U) exhibits functions as a binder, a pigment dispersing resin, etc.
The content of the polyurethane urea resin (U) in the printing ink of the present invention is preferably 5 to 40% by weight, more preferably 10 to 30% by weight, based on the weight of the printing ink, from the viewpoints of adhesiveness, mechanical strength and handleability.

The printing ink of the present invention may also contain additives such as pigments, other resins, and pigment dispersants that are generally preferably used in printing inks, if necessary. The other resins and additives may each be used alone or in combination of two or more types.

The pigment is not particularly limited, and preferably, inorganic pigments and organic pigments used in printing inks can be used.
Examples of the other resins include polyamide resins, nitrocellulose, acrylic resins, vinyl acetate resins, styrene-maleic acid copolymer resins, chlorinated polypropylene resins, epoxy resins, and rosin resins, etc. The amount of these other resins used is preferably 30% by weight or less, more preferably 20% by weight or less, based on the weight of the printing ink.

There are no particular limitations on the method for producing the printing ink, and the printing ink can be produced by known methods, for example, using general-purpose ink production equipment such as a three-roll mill, ball mill, and sand grinder mill.

An example of the formulation of the printing ink of the present invention is as follows.
Polyurethane urea resin (U): 5 to 40% by weight (preferably 10 to 30% by weight)
Pigment: 5 to 40% by weight (preferably 10 to 30% by weight)
Other resins: 0 to 30% by weight (preferably 0 to 20% by weight)
Solvent: 30 to 80% by weight (preferably 40 to 70% by weight)

The printing ink made using the polyurethane urea resin solution of the present invention may be used as a one-component printing ink, but may also be used as a two-component printing ink in combination with, for example, a polyisocyanate-based curing agent. In this case, suitable polyisocyanate-based curing agents include, for example, an adduct from 1 mole of trimethylolpropane and 3 moles of 1,6-hexamethylene diisocyanate, tolylene diisocyanate, or IPDI; an isocyanurate group-containing trimer synthesized by cyclic trimerization of the isocyanate groups of 1,6-hexamethylene diisocyanate or IPDI; a partial biuret reaction product derived from 1 mole of water and 3 moles of 1,6-hexamethylene diisocyanate, and a mixture of two or more of these. When used as a two-component printing ink, the amount of polyisocyanate-based curing agent used is preferably 0.5 to 10% by weight based on the weight of the polyurethane urea resin (U).

Printing methods using the printing ink of the present invention include conventional printing methods used for printing on plastic films, such as special gravure printing, inkjet printing, offset printing, and thermal transfer printing.

The printing ink of the present invention has particularly excellent adhesion to plastics and can be suitably used for printing on various plastic films such as polyester films, nylon films, polyolefin films (surface-treated or untreated polypropylene films, polyethylene films, etc.), polyvinyl acetal films, acetate films, polyvinyl chloride films, and films obtained by depositing aluminum on these films.

<Coating Agent>
The coating agent of the present invention contains the polyurethane urea resin solution of the present invention. In the coating agent of the present invention, the polyurethane urea resin (U) exhibits a function as a binder or the like.
The content of the polyurethane urea resin (U) in the coating agent of the present invention is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, based on the weight of the coating agent, from the viewpoints of adhesion, mechanical strength and handleability.

The coating agent of the present invention may contain other resins in addition to the polyurethane urea resin (U), such as polyurethane resins other than (U), polyester resins, polyacrylic resins, and epoxy resins. From the viewpoint of adhesion, the content of the other resins is preferably 50% by weight or less, and more preferably 30% by weight or less, based on the weight of the polyurethane urea resin (U).

Any additives generally used in coating agents may be contained. Examples of additives include stabilizers (antioxidants, ultraviolet absorbers, etc.), fillers, colorants (dyes and pigments), flame retardants (antimony oxide, etc.), dispersants, defoamers, and leveling agents. The content of the additives is preferably 10% by weight or less, more preferably 0.5 to 5% by weight, based on the weight of (U) in the coating agent.
Examples of the antioxidant include hindered phenols [Irganox 1010 (Ciba-Geigy Co., Ltd.)] and hindered amines [Sanol LS770 (Ciba-Geigy Co., Ltd.)]. Examples of the ultraviolet absorber include triazoles [Tinuvin 320 (Ciba-Geigy Co., Ltd.)] and benzophenones [Cyasorb UV9 (Cyanamido Co., Ltd.)]. Examples of the filler include clay, calcium carbonate, barium sulfate, alumina, silica, carbon black, zinc oxide, calcium oxide, lead dioxide, titanium oxide, diatomaceous earth, glass fiber and its crushed products (cut glass, milled glass, glass flakes, etc.), talc, and mica.

The viscosity (20° C.) of the coating agent of the present invention is preferably from 100 to 5,000 mPa·s, and more preferably from 500 to 3,000 mPa·s, from the viewpoint of handleability.
The viscosity of the coating agent can be measured by a B-type viscometer in accordance with JIS-K7117-1.

Substrates to which the coating agent of the present invention can be applied include plastic molded bodies [polyolefins (polyethylene, polypropylene, etc.), polystyrene, ABS, polyvinyl chloride, polycarbonate, polyacetal, polyester, nylon, polyamide, polyurethane, modified PPO, polymethyl methacrylate, epoxy resin, phenolic resin, melamine resin, etc.], rubbers [natural rubber, synthetic rubber (chloroprene rubber, isoprene rubber, SBR, NBR, butyl rubber, EP rubber, etc.)], porous materials [wood, paper, cloth (woven or nonwoven fabrics of natural and synthetic fibers, etc.), plastic foams (polyolefin foam, polyurethane foam, etc.)], and inorganic materials [metals (iron, tinplate, galvanized iron, aluminum, galvanized steel sheet, etc.), glass, roof tile slate, ceramics, etc.]. Of these, plastics are preferred, and polyolefins, polyesters, and nylons are more preferred.

The coating agent of the present invention exhibits excellent performance, particularly as a primer for painting polyolefin resin molded bodies (such as automobile bumpers) and electrodeposition-coated steel sheets of automobile bodies. When used as a primer for painting, the amount of coating (after drying) can be selected according to the purpose, but is preferably 1 to 50 μm, more preferably 2 to 40 μm. As a coating method, known methods such as spray coating, brush coating, roll coating, flow coating, and immersion can be used. The drying (baking) temperature is preferably 40 to 130°C, more preferably 60 to 80°C, and the drying time is preferably 0.5 to 60 minutes, more preferably 3 to 30 minutes.

As the topcoat, known thermosetting or thermoplastic resin paints such as acrylic enamel, one-component and two-component polyurethane paints, acrylic urethane paints, acrylic melamine paints, and alkyd melamine paints are used. The coating amount of the topcoat (after drying) is preferably 20 to 80 μm. Methods for coating and drying the topcoat include known methods such as the two-coat one-bake (wet-on-wet coating) method and the two-coat two-bake (dry-on-wet coating) method. The topcoat layer may consist of one layer or two or more layers.

<Adhesive>
The adhesive of the present invention contains the polyurethane urea resin solution of the present invention.
The content of the polyurethane urea resin (U) in the adhesive of the present invention is preferably 1 to 50% by weight, more preferably 2 to 40% by weight, based on the weight of the adhesive, from the viewpoints of adhesion, mechanical strength, and handleability.

The adhesive of the present invention may further contain various additives, if necessary, in addition to the polyurethane urea resin solution of the present invention.
The additives include one or more selected from the group consisting of tackifiers, plasticizers, adsorbents, colorants, flame retardants, fillers, lubricants, nucleating agents, antioxidants, release agents, light stabilizers, fragrances, and ultraviolet absorbers.

Examples of tackifiers include terpene resins, terpene phenol resins, phenol resins, aromatic hydrocarbon modified terpene resins, rosin resins, modified rosin resins, synthetic petroleum resins (aliphatic, aromatic or alicyclic synthetic petroleum resins, etc.), coumarone-indene resins, xylene resins, styrene-based resins, dicyclopentadiene resins, and hydrogenated versions of these resins that have unsaturated double bonds that can be hydrogenated.

As the plasticizer, various plasticizers [such as those described in Adhesion Technology Vol. 20, (2), 21 (2000)] can be used, including process oils (paraffin, naphthene or aromatic compound type); liquid resins (Mn 300 to 6,000, such as liquid polybutene, liquid polybutadiene, liquid polyisoprene); hydrogenated versions of such liquid resins; low molecular weight (Mn 300 to 10,000) polyisobutylene; and mixtures of two or more of these.

Adsorbents include alumina, silica gel, molecular sieves, etc.

Colorants include inorganic pigments [white pigments, cobalt compounds, iron compounds, sulfides, etc.], organic pigments [azo pigments, polycyclic pigments, etc.], dyes [azo-based, indigoid-based, sulfide-based, alizarin-based, acridine-based, thiazole-based, nitro-based, aniline-based, etc.], etc.

Examples of flame retardants include halogen-containing flame retardants, sulfur-containing flame retardants, phosphorus-containing flame retardants, and metal hydroxide-containing flame retardants.

Examples of fillers include inorganic fillers (calcium carbonate, talc, clay, etc.).

Examples of lubricants include calcium stearate, butyl stearate, and oleic acid amide.

Nucleating agents include sorbitol, metal phosphates, metal benzoates, metal phosphates, etc.

Examples of antioxidants include phenol compounds [monocyclic phenols (e.g., 2,6-di-t-butyl-p-cresol), bisphenols [e.g., 2,2'-methylenebis(4-methyl-6-t-butylphenol)], polycyclic phenols [e.g., 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene], etc.], sulfur compounds (e.g., dilauryl 3,3'-thiodipropionate), phosphorus compounds (e.g., triphenyl phosphite), etc.].

Examples of release agents include carboxy-modified silicone oil and hydroxyl-modified silicone oil.

Examples of light stabilizers include hindered amine compounds [(bis-2,2,6,6-tetramethyl-4-piperidyl) sebacate, etc.].

Fragrances include diterpenes, limonene, etc.

Examples of ultraviolet absorbers include benzotriazoles [2-(2'-hydroxy-5'-methylphenyl)benzotriazole, etc.], benzophenones [2-hydroxy-4-methoxybenzophenone, etc.], and salicylates [phenyl salicylate, etc.].

The total content of the additives is preferably 50% by weight or less, more preferably 0.002 to 40% by weight, and particularly preferably 1 to 30% by weight, based on the total weight of the adhesive, from the viewpoint of the additive effect and adhesiveness.

When the above additives overlap, each additive should not be used in the amount that produces the corresponding additive effect, but should be adjusted according to the purpose of use, taking into consideration that the effects of other additives can also be obtained at the same time.

<Adhesive>
The adhesive of the present invention can be used to bond adherends to obtain an adherend.
Examples of the adherend include various plastics [polyolefins (polyethylene and polypropylene, etc.), polyesters, nylons, polystyrenes, syndiotactic polystyrenes, ABS, polyvinyl chloride, polycarbonates, polyacetals, polyamides, polyimides, polyurethanes, modified PPOs, polymethyl methacrylates, liquid crystal polymers, epoxy resins, phenolic resins, and melamine resins, etc.], rubbers [natural rubbers, synthetic rubbers (chloroprene rubbers, isoprene rubbers, SBRs, NBRs, butyl rubbers, and EP rubbers, etc.)], porous materials [wood, paper, cloths (woven or nonwoven fabrics of natural and synthetic fibers, etc.), plastic foams (polyolefin foams, polyurethane foams, etc.)], and inorganic materials [metals (copper, iron, tinplate, galvanized iron, aluminum, and galvanized steel sheets, etc.), glass, tile slates, and ceramics, etc.]. Among these, from the viewpoint of adhesion, plastic substrates are preferred, and polyolefins, polyesters, and nylons are more preferred.
It is preferred that at least one of the adherends is a polyolefin substrate.

The method for applying the adhesive of the present invention to the substrate is not particularly limited, and the adhesive can be applied with a spatula, comb, roller, trowel, rake, etc., or by extrusion or spraying with a sealing gun, or by hand or machine application to form a coating film, film sheet, thick object, or other desired shape of any thickness. In addition, a compound with anti-sagging properties can be added and applied to vertical surfaces, wall surfaces, curved surfaces, depressions, etc. with a roller, ricin gun, airless gun, etc. to form a coating film.

The adhesive of the present invention can be used as an adhesive for automobile parts using polyolefin parts such as bumpers, for building parts, and for polyolefin-based laminate films, and is particularly useful as an adhesive for automobile parts and laminate films.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. In the following, "parts" refers to parts by weight.

Production Example 1
In a reaction vessel, 1000 parts of polyolefin (A0-1) [Mn: 113,000, isotacticity: 50%, trade name "Vistamaxx3980", manufactured by ExxonMobil] with 91% by weight of propylene and 9% by weight of ethylene as constituent monomers was charged, and while passing nitrogen through the liquid phase, it was heated and melted with a mantle heater, and thermal degradation was performed under the condition of 370 ° C. for 60 minutes while stirring, to obtain polyolefin (A1-1). Here, 65 parts of maleic anhydride (E-1) was charged, and after nitrogen replacement, it was heated to 180 ° C. under nitrogen passing and dissolved uniformly, and a solution in which 5 parts of radical initiator [dicumyl peroxide, trade name "Percumyl D", manufactured by NOF Corp.] (F-1) was dissolved in 50 parts of xylene was dropped over 5 minutes, and stirring was continued for 1 hour under xylene reflux. Thereafter, unreacted maleic anhydride was distilled off under reduced pressure (1.5 kPa) to obtain an acid-modified polyolefin (X-1). 500 parts of (X-1) and 32 parts of 2-aminoethanol (G-1) were charged into a similar reaction vessel and reacted at 180°C for 1 hour under a nitrogen gas atmosphere. Next, unreacted 2-aminoethanol was distilled off at 180°C and a reduced pressure of 2.7 kPa to obtain a hydroxyl-containing modified polyolefin (A-1). (A-1) had a hydroxyl value of 29, an acid value of 0.2, an Mn of 3,500, and an isotacticity of 43%. The number of double bonds per 1,000 carbons of the polyolefin (A1-1) used for modification was 7.5.

Production Example 2
A reaction was carried out in the same manner as in Production Example 1 under the conditions described in Table 1, except that a polyolefin (A0-2) having 85% by weight of propylene and 15% by weight of ethylene as constituent monomers [Mn: 76,000, isotacticity: 20%, product name "Vistamaxx 6202", manufactured by Exxon Mobil] was used in the reaction vessel, to obtain an acid-modified polyolefin (X-2), which was then reacted with 2-aminoethanol (G-1) in the same manner as in Production Example 1 to obtain a hydroxyl group-containing modified polyolefin (A-2). The results are shown in Table 1.

Production Example 3
A polyolefin (A0-1) having 91% by weight of propylene and 9% by weight of ethylene as constituent monomers was used and reacted in the same manner as in Production Example 1 under the conditions shown in Table 1 to obtain an acid-modified polyolefin (X-3), which was then reacted with 2-aminoethanol (G-1) in the same manner as in Production Example 1 to obtain a hydroxyl group-containing modified polyolefin (A-3). The results are shown in Table 1.

Production Example 4
A polyolefin (A0-2) having 85% by weight of propylene and 15% by weight of ethylene as constituent monomers was used and reacted in the same manner as in Production Example 1 under the conditions shown in Table 1 to obtain an acid-modified polyolefin (X-4), which was then reacted with 2-aminoethanol (G-1) in the same manner as in Production Example 1 to obtain a hydroxyl group-containing modified polyolefin (A-4). The results are shown in Table 1.

Production Example 5
1000 parts of polyolefin (A0-3) [Mn: 200,000, isotacticity: 33%, trade name "Tafmer S4030", manufactured by Mitsui Chemicals] containing 73% by weight of propylene and 27% by weight of ethylene as constituent monomers was charged, and while passing nitrogen through the liquid phase, it was heated and melted with a mantle heater, and thermally degraded at 380 ° C for 80 minutes while stirring to obtain polyolefin (A1-3). 47 parts of maleic anhydride (E-1) was charged thereto, and after nitrogen replacement, it was heated to 200 ° C under nitrogen aeration and continued stirring for 10 hours. Thereafter, unreacted maleic anhydride was distilled off under reduced pressure (1.5 kPa) to obtain acid-modified polyolefin (X-5). 500 parts of (X-5) and 23 parts of 2-aminoethanol (G-1) were charged in a similar reaction vessel, and reacted at 180 ° C for 1 hour under a nitrogen gas atmosphere. Next, unreacted 2-aminoethanol was distilled off at 180° C. under a reduced pressure of 2.7 kPa to obtain a hydroxyl group-containing modified polyolefin (A-5). The results are shown in Table 1.

Production Example 6
A polyolefin (A0-4) [Mn: 40,000, isoactivity: 3%, product name "TAFMER P0280", manufactured by Mitsui Chemicals, Inc.] having 27% by weight of propylene and 73% by weight of ethylene as constituent monomers was used, and a reaction was carried out in the same manner as in Production Example 1 under the conditions shown in Table 1 to obtain an acid-modified polyolefin (X-6), which was then reacted with 2-aminoethanol (G-1) in the same manner as in Production Example 1 to obtain a hydroxyl group-containing modified polyolefin (A- 6 ). The results are shown in Table 1.

Comparative Production Example 1
Except for using a polyolefin (A0-5) having constituent monomers of 98% by weight of propylene and 2% by weight of ethylene [Mn: 100,000, isotacticity: 90%, product name "SunAllomer PZA20A", manufactured by SunAllomer Co., Ltd.], a reaction was carried out in the same manner as in Production Example 1 under the conditions shown in Table 1 to obtain an acid-modified polyolefin (X-7), which was then reacted with 2-aminoethanol (G-1) in the same manner as in Production Example 1 to obtain a hydroxyl group-containing modified polyolefin (A'-1). The results are shown in Table 1.

Comparative Production Example 2
Except for using polyolefin (A0-2) having 85% by weight of propylene and 15% by weight of ethylene as constituent monomers, the reaction was carried out in the same manner as in Production Example 1 under the conditions shown in Table 1 to obtain acid-modified polyolefin (X-8), which was then reacted with 2-aminoethanol (G-1) in the same manner as in Production Example 1 to obtain hydroxyl group-containing modified polyolefin (A'-2). The results are shown in Table 1.

Example 1
In a reaction vessel equipped with a stirrer, 223 parts of the hydroxyl-containing modified polyolefin (A-1) obtained in Production Example 1, 3.20 parts of 1,4-butanediol, and 52.11 parts of IPDI were charged and reacted for 6 hours at 110°C under a nitrogen atmosphere to obtain a urethane prepolymer having an NCO content of 3.50% by weight. After cooling to 40°C, 350 parts of methylcyclohexane were added to obtain a homogeneous solution. Next, 350 parts of isopropanol were added and stirred until homogeneous, after which 16.43 parts of isophoronediamine and 5.06 parts of diethanolamine were added and reacted at 40°C for 1 hour to obtain a solution of polyurethane urea resin (U-1) of the present invention. The viscosity of the solution of (U-1) at 20°C was 1,000 mPa·s, and the Mn of (U-1) was 13,000.

Examples 2 to 14, Comparative Examples 1 to 3
The reaction was carried out in the same manner as in Example 1, except that the raw materials used were changed to the types and amounts shown in Table 2, to obtain solutions of polyurethane urea resins (U-2) to (U-14) and (U'-1) to (U'-3). The results are shown in Table 2.

The raw materials used in the examples and comparative examples are as follows.
Polyol (H-1):
Kuraray Polyol P-2010: poly(3-methyl-1,5-pentanediol, adipic acid polycondensate) with Mn=2,000, manufactured by Kuraray Co., Ltd.
Polyol (H-2):
PTMG2000: Poly(oxytetramethylene) glycol with Mn = 2,000 [manufactured by Mitsubishi Chemical Corporation]
Polyol (H-3):
Sannix PP-2000: Polypropylene glycol with Mn=2,000 [manufactured by Sanyo Chemical Industries, Ltd.]
Polyol (H-4):
Actflow UT-1001: Polyacryldiol with Mn=2,000 [manufactured by Soken Chemical Industries, Ltd.]

Examples 15 to 28 and Comparative Examples 4 to 6
The storage stability of the polyurethane urea resin (U) solutions obtained in Examples 1 to 14 and Comparative Examples 1 to 3 at 25° C. was evaluated according to the following criteria by comparing the appearance immediately after production and one day after production. The results are shown in Table 3.
<Evaluation criteria>
◯: No change in appearance.
×: The solution separated.

Using the solutions of polyurethane urea resin (U) obtained in Examples 1 to 14 and Comparative Examples 1 to 3, white pigment dispersions were prepared according to the following recipe and adhesion tests were conducted. The results are shown in Table 3.

[Preparation of White Pigment Dispersion]
A mixture of 35 parts of a polyurethane urea resin (U) solution, 35 parts of titanium oxide ("Titanix JR809" manufactured by Teika Corporation), 10 parts of isopropyl alcohol, 20 parts of ethyl acetate, and 100 parts of glass beads was kneaded in a paint conditioner (manufactured by Red Devil Co., Ltd.) for 1 hour, and the glass beads were removed by filtration to obtain a white pigment dispersion.

[Adhesion test method]
A white pigment dispersion was applied to the treated surfaces of a surface-treated polypropylene film (OPP) [Toyobo Co., Ltd.'s "Pylen P-2161" (thickness 30 μm)], a surface-treated polyester film (PET) [Toyobo Co., Ltd.'s "Espet E-5102" (thickness 12 μm)], and a surface-treated nylon film [Toyobo Co., Ltd.'s "Harden N-1130" (thickness 15 μm)] using a bar coater so that the thickness after drying would be 2 to 3 μm, and the test pieces were prepared by drying at 60° C. for 1 minute, and then cellophane tape (Nichiban Co., Ltd., 12 mm wide) was applied to the coated surface, and one end of the cellophane tape was rapidly peeled off in a direction perpendicular to the coated surface, observing the state of the coated surface and determining the area percentage where the ink was not peeled off. The untreated surface of each film that had not been surface-treated was also tested in the same manner.

Dry films were prepared according to the following recipes using the solutions of the polyurethane urea resins (U) obtained in Examples 1 to 14 and Comparative Examples 1 to 3, and the physical properties of the films were measured. The results are shown in Table 3.
[Production of dried film]
A release film was attached to a polypropylene mold, and for the solution of polyurethane urea resin (U) obtained in the Examples and Comparative Examples, a polyurethane urea resin solution previously prepared to a solid content concentration of 20% by weight was gently poured into the mold so that the film thickness after drying would be approximately 200 μm. The polyurethane urea resin solution was then spread uniformly over the entire mold, and the mold was left to stand at 25° C. for 12 hours. The mold was then dried at 70° C. for 1 hour using a circulating air dryer, and then further dried at 105° C. under reduced pressure of 1.3 kPa for 1 hour to obtain a dry film.

<Coating film properties>
[100% modulus, breaking strength and breaking elongation]
The dried film obtained above was cut into a dumbbell-shaped test piece No. 3 in accordance with JIS K6251, and the 100% modulus, breaking strength, and breaking elongation were measured at a tensile speed of 500 mm/min using an autograph [Shimadzu Corporation "AGS-500D"]. The 100% modulus and breaking strength are indicators of the strength of the coating film when applied to the surface of a substrate as a paint, printing ink, or coating agent, and it can be said that a 100% modulus of 1.0 MPa or more and a breaking strength of 3.0 MPa or more are usable levels. In addition, the breaking elongation is an indicator of the conformability to the substrate when used as a paint, printing ink, coating agent, or adhesive, and it can be said that a breaking elongation of 300% or more conforms to the substrate and does not deteriorate in adhesion even if the substrate is deformed.

From the results in Table 3, it can be seen that the polyurethane urea resin solution of the present invention has excellent solution stability, does not contain harmful substances such as chlorine and toluene, exhibits excellent adhesion to not only surface-treated plastic substrates but also to untreated plastic substrates, and has good mechanical strength. On the other hand, from the evaluation results of Comparative Example 6, it can be seen that the conventional polyurethane urea resin solution has good solution stability but extremely poor adhesion to polyolefin films and untreated polyester and nylon films. In addition, from the evaluation results of Comparative Examples 4 and 5, it can be seen that the polyurethane urea resin solution using the hydroxyl-modified polyolefin (A'-1) or (A'-2) whose Mn is too small or too large, whose polyolefin structure contains too many α-olefin structures, or whose isotacticity is too large, has poor solution stability and extremely poor adhesion to plastic substrates.

The polyurethane urea resin solution of the present invention and the paint, printing ink, coating agent and adhesive using the same do not contain harmful substances such as chlorine and toluene, do not impair mechanical strength, and exhibit particularly excellent adhesion to plastics (polyolefin, polyester, nylon, etc.) that have not been subjected to corona treatment or plasma treatment, and have excellent solution stability, so that the paint containing the polyurethane urea resin solution of the present invention can be used as automobile paints such as automobile parts and automobile bodies, paints for electrical appliances, architectural paints, and rust-preventive paints, and is particularly useful as automobile paints. In addition, the printing ink containing the polyurethane urea resin solution of the present invention is particularly suitable as a printing ink for special gravure printing, flexographic printing, inkjet printing, offset printing, and thermal transfer printing. In addition, the polyurethane urea resin solution of the present invention is useful not only for the above-mentioned applications, but also as a coating agent for adhesives and paper, etc.

Claims (7)

A polyurethane urea resin solution containing a polyurethane urea resin (U) having as essential constituent monomers a hydroxyl-modified polyolefin (A), a polyisocyanate (B), and a chain extender (C) having a number average molecular weight or chemical formula weight of less than 500, and a solvent (S), wherein the chain extender (C) contains a polyamine (C1), the number of hydroxyl groups per molecule of the hydroxyl-modified polyolefin (A) is 1.5 to 2.0, the weight ratio (ethylene:α-olefin) of the constituent monomers of the hydroxyl-modified polyolefin (A) to an α-olefin having 3 to 8 carbon atoms is 9:91 to 95:5, the isotacticity of the α-olefin unit chain portion of the hydroxyl-modified polyolefin (A) is 1 to 50%, and the number average molecular weight of the hydroxyl-modified polyolefin (A) is 1,000 to 6,000. The polyurethane urea resin solution according to claim 1, wherein the hydroxyl value of the hydroxyl-modified polyolefin (A) is 14 to 110 mg KOH/g. The polyurethane urea resin solution according to claim 1 or 2, wherein the hydroxyl group-modified polyolefin (A) is a reaction product of an acid-modified polyolefin (X) obtained by modifying a polyolefin (A1) having a carbon-carbon double bond with an unsaturated (poly)carboxylic acid (anhydride) (E) and an amino alcohol (G), or a reaction product of the acid-modified polyolefin (X) and an alkylene oxide, and the polyolefin (A1) having a carbon-carbon double bond is a thermal degradation product of a polyolefin (A0) having a number average molecular weight of 60,000 to 400,000 . A paint containing the polyurethane urea resin solution according to any one of claims 1 to 3. A printing ink containing the polyurethane urea resin solution according to any one of claims 1 to 3. A coating agent containing the polyurethane urea resin solution according to any one of claims 1 to 3. An adhesive containing the polyurethane urea resin solution according to any one of claims 1 to 3.