Aqueous coating composition

Abstract

An aqueous coating composition is provided comprising (a) a first polyurethane dispersion comprising a first polyurethane having a Tg of 5°C to 20°C, (b) a second polyurethane dispersion comprising a second polyurethane having a Tg of -40°C to -60°C, and (c) a polyacrylic emulsion comprising an acrylic (co)polymer having a Tg of -40°C to -20°C. Also provided is a method of preparing a laminate using the aqueous coating composition, and a laminate prepared therefrom.

Description

Technical Field

[0001] This disclosure relates to the technical field of coating materials, and more particularly to an aqueous coating composition comprising a polyacrylic emulsion and two different polyurethane dispersions. Background Technology

[0002] PTP (Press-through Packaging) sheets are among the most popular packaging materials for medical packs worldwide, and the adhesives used to prepare PTP are primarily solvent-based (SB). These adhesives are becoming increasingly unpopular due to the organic solvents emitted during manufacturing processes (such as coating and curing steps) and subsequent storage, transportation, and use. In recent years, due to stricter VOC emission regulations in many countries, PTP sheet suppliers have been working to develop environmentally friendly solutions to replace the solvent-based adhesives currently used to prepare PTP foils. Several water-based (WB) coating materials for PTP applications have been reported, specifically formulating several emulsions or dispersions of different polymers. However, none of these WB coating materials achieves a combination of superior performance characteristics, including VOC-free (volatile organic compound) content, economic viability, and superior heat-sealing strength and anti-blocking properties compared to, or at least comparable to, commercially available SB (solvent-based) coating materials.

[0003] As should be understood from the preceding text, there remains a strong desire for a WB coating composition that can be easily prepared at a limited cost and exhibits the excellent performance characteristics described above.

[0004] After continuous exploration, we have surprisingly discovered a WB polyurethane coating composition that can achieve the above objectives. Summary of the Invention

[0005] This disclosure provides a unique waterborne coating composition for PTP foil applications, a method for preparing a laminate using the waterborne coating composition, and a laminate prepared therefrom.

[0006] In a first aspect of this disclosure, an aqueous coating composition is provided comprising: (a) a first polyurethane dispersion comprising a first polyurethane with a Tg of 5°C to 20°C; (b) a second polyurethane dispersion comprising a second polyurethane with a Tg of -40°C to -60°C; and (c) a polyacrylic emulsion comprising an acrylic (co)polymer with a Tg of -40°C to -20°C.

[0007] According to one embodiment of this disclosure, the first polyurethane is derived from a first raw material, which, based on the total dry weight of the first polyurethane dispersion, comprises 15% to 45% by weight of at least one first monomer diisocyanate, 40% to 75% by weight of at least one first polyol, and 2% to 15% by weight of at least one first internal emulsifier. According to another embodiment of this disclosure, the second polyurethane is derived from a second raw material, which, based on the total dry weight of the second polyurethane dispersion, comprises 20% to 35% by weight of at least one second monomer diisocyanate, 50% to 75% by weight of at least one second polyol, and 2% to 10% by weight of at least one second internal emulsifier. According to another embodiment of this disclosure, the acrylic (co)polymer is derived from a third raw material, which comprises 60% to 90% by weight of at least one (meth)acrylic monomer and 10% to 40% by weight of at least one styrene monomer.

[0008] According to another embodiment of this disclosure, the first monomer diisocyanate and the second monomer diisocyanate are each independently selected from the group consisting of: C2-C 16 Aliphatic diisocyanates, C6-C 16 Aromatic diisocyanates, C5-C 16 Alicyclic diisocyanates and combinations thereof.

[0009] According to another embodiment of this disclosure, the first polyol and the second polyol are each independently selected from the group consisting of: C2-C polyols comprising at least two hydroxyl groups. 16 Aliphatic polyols, including C6-C groups with at least two hydroxyl groups 15 Alicyclic or aromatic polyols, including at least two hydroxyl groups, C7-C 15 Aromatic aliphatic polyols, poly(C4-C5) with an average molecular weight of 500 to 5,000 12 (Lactone) polyols, polycarbonate polyols with an average functionality of 2 to 5 and a molecular weight of 400 to 5,000, polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 400 to 12,000, polyester polyols with an average functionality of 2 to 5 and a molecular weight of 500 to 5,000, and any combination thereof.

[0010] According to another embodiment of this disclosure, the first polyol comprises a C4-C group including at least two hydroxyl groups. 16 The product comprises at least one of branched aliphatic polyols and polycarbonate polyols having an average functionality of 2 to 5 and a molecular weight of 500 to 3,000, and optionally further comprises poly(C4-C) polyols having an average molecular weight of 800 to 4,000. 12One or more of the following: lactone polyols, polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 800 to 5,000, and polyester polyols with an average functionality of 2 to 5 and a molecular weight of 800 to 4,000.

[0011] According to another embodiment of this disclosure, the second polyol comprises a linear polyester polyol having an average functionality of 2 to 5 and a molecular weight of 800 to 5,000, and optionally further comprises a poly(C4-C5) polyol having an average molecular weight of 500 to 5,000. 12 One or both of the following: lactone polyols and polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 400 to 12,000.

[0012] According to another embodiment of this disclosure, the first polyol is selected from:

[0013] (a) A blend of a polycarbonate polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000, a polylactone polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000, and a polyester polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000; and

[0014] (b) A blend of trimethylpentanediol, a polyester polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000, and a polyether polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000.

[0015] According to another embodiment of this disclosure, the second polyol is selected from...

[0016] (c) A linear polyester polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000; and

[0017] (d) A linear polyester polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000 and a poly(C4-C) polyol with an average functionality of 2 and an average molecular weight of 1,000 to 3,000. 12 A blend of at least one of a lactone polyol and a polyether polyol having an average functionality of 2 and an average molecular weight of 1,000 to 3,000.

[0018] According to another embodiment of this disclosure, the first internal emulsifier and the second internal emulsifier are each independently selected from the group consisting of: C2-C molecules substituted with at least two hydroxyl or amino groups. 16 Aliphatic acids or their salts, C5-C substituted with at least two hydroxyl or amino groups 16 Alicyclic acids or their salts, and any combination thereof.

[0019] According to another embodiment of this disclosure, the acrylic copolymer of the polyacrylic emulsion is derived from a third raw material, which, based on the total solids weight of the polyacrylic emulsion, comprises 60% to 80% by weight of at least one C1-C. 12 Alkyl (meth)acrylates, 1% to 10% by weight of (meth)acrylic acid, and 10% to 30% by weight of styrene and / or C1-C6 alkyl-substituted styrene.

[0020] According to another embodiment of this disclosure, the weight ratio of the first polyurethane dispersion, the second polyurethane dispersion and the polyacrylic emulsion is (10-15):(1-7):(1-8).

[0021] In a second aspect, this disclosure provides a method for producing a laminated material, the method comprising:

[0022] (a) Providing metal foil and substrate;

[0023] (b) Applying the aqueous coating composition of this disclosure to at least one surface of a metal foil to form a wet coating, then curing and drying the wet coating to form a dry coating; and

[0024] (c) Laminating the substrate onto the dry coating under pressure and elevated temperature to form a laminate.

[0025] In a third aspect, this disclosure provides a laminate comprising a metal foil, a substrate, and an adhesive layer sandwiched therebetween, wherein the adhesive layer is derived from the aqueous coating composition of this disclosure.

[0026] In a fourth aspect, this disclosure provides the use of the aqueous coating compositions of this disclosure in the preparation of PTP (pressure puncture packaging) foil.

[0027] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and not intended to limit the invention as claimed. Detailed Implementation

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Furthermore, all publications, patent applications, patents, and other references mentioned herein are incorporated herein by reference.

[0029] As disclosed herein, “and / or” means “and, or as an alternative”. Unless otherwise specified, all ranges include end values.

[0030] As disclosed herein, the terms "composition," "formulation," or "mixture" refer to a physical blend of different components obtained by simply mixing the different components using physical means. The term "dispersion" refers to a physical blend comprising a liquid continuous phase and at least one solid and / or liquid dispersed phase (preferably a solid dispersed phase) dispersed in the liquid continuous phase. "Dispersion" is a general concept that may include a solution (i.e., the dispersed phase is soluble in the continuous phase) or a suspension (i.e., the dispersed phase is at least partially insoluble in the continuous phase). According to a preferred embodiment of this disclosure, the solid dispersed phase is uniformly dispersed in the liquid continuous phase. As used herein, the term "emulsion" refers to a substantially stable physical mixture of a liquid continuous phase and at least one solid and / or liquid dispersed phase dispersed in the liquid continuous phase, wherein the dispersed phase is partially or substantially immiscible with the liquid continuous phase. The stability of the emulsion preferably derives from electrostatic repulsion.

[0031] As disclosed herein, the term “glass transition temperature” or “Tg” is determined by differential scanning calorimetry (DSC).

[0032] As disclosed herein, unless otherwise specified, all percentages mentioned herein are by weight, temperatures are in °C, and the average molecular weight is the exponential average molecular weight (Mn).

[0033] As used herein, the term “(meth)acrylate” refers to acrylate or methacrylate, the term “(meth)acrylic acid” refers to acrylic acid or methacrylic acid, and the term “(co)polymer” refers to polymer or copolymer.

[0034] According to one embodiment of this disclosure, the waterborne coating composition of this disclosure is substantially free of any organic solvents intentionally added thereto. For example, based on the total weight of the waterborne coating composition, the total amount of organic solvents is less than 5% by weight, or less than 4%, preferably less than 2%, more preferably less than 1%, more preferably less than 0.1%, more preferably less than 0.01%, more preferably less than 100 ppm, more preferably less than 50 ppm, more preferably less than 10 ppm, and more preferably less than 1 ppm. As disclosed herein, the term "solvent-type" refers to an organic liquid whose function is to dissolve only one or more solid, liquid, or gaseous materials without initiating any chemical reaction. In other words, although some organic compounds that are generally considered "solvents" in polymerization techniques, such as ethylene glycol, propylene glycol, and other polyols, can be used to prepare one or more polymer components such as polyurethane, they are not considered "solvents" because they primarily act as isocyanate reactive functional substances, adhesion promoters, chain extenders, modifiers, emulsifiers, etc., by initiating chemical reactions. According to a preferred embodiment of this disclosure, the waterborne coating composition contains only water as a solvent and does not contain any organic solvents intentionally added thereto.

[0035] In the context of this disclosure, all raw materials used to prepare the first polyurethane are described with the term "first," and raw materials used to prepare the second polyurethane are described with the term "second," so as to clearly distinguish them from each other.

[0036] According to various embodiments of this disclosure, the waterborne coating composition comprises (a) a first polyurethane dispersion, (b) a second polyurethane dispersion different from the first polyurethane dispersion, and (c) a polyacrylate emulsion, and the formulation design of each component will be specifically described in the following paragraphs.

[0037] First polyurethane dispersion

[0038] In one embodiment of this disclosure, the first polyurethane dispersion comprises a first polyurethane dispersed in water, and the Tg of the first polyurethane dispersion is from 5°C to 20°C, such as from 10°C to 15°C, or within a numerical range obtained by combining any two of the following values: 5°C, 6°C, 7°C, 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C. According to one embodiment of this disclosure, based on the total weight of the first polyurethane dispersion, the solids content of the first polyurethane dispersion is from 20% to 50% by weight, such as 22% to 48%, or 24% to 46%, or 25% to 45%, or 27% to 42%, or 30% to 40%, or 32% to 38%, or 34% to 36%. Alternatively, the first polyurethane dispersion may have a solids content within a numerical range obtained by combining any two of the following percentage values: 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, 35 wt%, 36 wt%, 37 wt%, 38 wt%, 39 wt%, 40 wt%, 41 wt%, 42 wt%, 43 wt%, 44 wt%, 45 wt%, 46 wt%, 47 wt%, 48 wt%, 49 wt%, and 50 wt%.

[0039] According to one embodiment of this disclosure, the first polyurethane is in the form of fine particles. For example, the fine particles of the first polyurethane may have a particle size of 10 nm to 500 nm, or 20 nm to 450 nm, or 30 nm to 400 nm, or 50 nm to 350 nm, or 60 nm to 300 nm, or 80 nm to 250 nm, or 90 nm to 200 nm, or 100 nm to 180 nm, or 120 nm to 150 nm, or may be within a numerical range obtained by combining any two of the above endpoint values.

[0040] According to one embodiment of this disclosure, a first polyurethane is prepared by reacting at least one first monomer diisocyanate with at least one first polyol and at least one first internal emulsifier.

[0041] According to one embodiment of this disclosure, the first monomeric diisocyanate may be selected from the group consisting of: C2-C 16 Aliphatic diisocyanates, C6-C 16 Aromatic diisocyanates, C5-C 16 Alicyclic diisocyanates and combinations thereof. Alicyclic diisocyanates may include, but are not limited to, ethylene diisocyanate, propylene diisocyanate, butyl diisocyanate, pentamethylene diisocyanate, and hexamethylene diisocyanate (HDI). Alicyclic diisocyanates may include, but are not limited to, cyclopentyl diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate (IPDI), and methylene-bis-(4-cyclohexyl isocyanate) (HMDI). Preferred aromatic diisocyanates are selected from phenyl diisocyanate, methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), carbodiimide-modified MDI, naphthyl diisocyanate, and combinations thereof. TDI can generally be used with any commonly used isomer distribution. The most commonly used TDI isomer distribution is 80% 2,4-isomer and 20% 2,6-isomer. TDI with other isomer distributions may also be used. When MDI is used, it is preferably pure 4,4′-MDI or any combination of MDI isomers. More preferably, it is pure 4,4′-MDI and any combination of 4,4′-MDI with other MDI isomers. When using a combination of 4,4′-MDI with other MDI isomers, the preferred concentration of 4,4′-MDI is 25% to 75% of all MDI isomers. According to an alternative embodiment of this disclosure, examples of aromatic diisocyanates include, but are not limited to, isomers of methylene diphenyl diisocyanate (“MDI”) such as 4,4-MDI, 2,4-MDI and 2,2′-MDI, or modified MDIs such as carbodiimide-modified MDI or urethane-modified MDI; isomers of toluene diisocyanate (“TDI”) such as 2,4-TDI, 2,6-TDI; isomers of naphthalene diisocyanate (“NDI”) such as 1,5-NDI; and combinations thereof. In a more preferred embodiment of this disclosure, the first monomer diisocyanate may be selected from the group consisting of: 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-diisocyanodicyclohexylmethane, diisocyanomethylcyclohexane, and any combination thereof.

[0042] Based on the total solid weight of the first polyurethane contained in the first polyurethane dispersion, the amount of the first monomer diisocyanate can be from 15 wt% to 45 wt%, such as within the numerical range obtained by combining any two of the following endpoint values: 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, 35 wt%, 36 wt%, 37 wt%, 38 wt%, 39 wt%, 40 wt%, 41 wt%, 42 wt%, 43 wt%, 44 wt%, and 45 wt%.

[0043] According to one embodiment of this disclosure, the monomeric diisocyanate preferably has a molecular weight Mn of less than 500 g / mol, more preferably less than 300 g / mol, and even more preferably less than 275 g / mol.

[0044] The first polyol used to prepare the first polyurethane is selected from the group consisting of: C2-C... comprising at least two hydroxyl groups. 16 Aliphatic polyols, including C6-C groups with at least two hydroxyl groups 15 Alicyclic or aromatic polyols, including at least two hydroxyl groups, C7-C 15 Aromatic aliphatic polyols, poly(C4-C5) with an average molecular weight of 500 to 8,000 12 (Lactone) polyols, polycarbonate polyols with an average functionality of 2 to 5 and a molecular weight of 400 to 5,000, polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 400 to 12,000, polyester polyols with an average functionality of 2 to 5 and a molecular weight of 500 to 5,000, and any combination thereof.

[0045] According to one embodiment of this disclosure, the first polyol comprises a C4-C group including at least two hydroxyl groups. 16 The product comprises at least one of branched aliphatic polyols and polycarbonate polyols having an average functionality of 2 to 5 and a molecular weight of 600 to 3,000, and may also include one or more of the following polyols as an option: poly(C4-C) polyols having an average molecular weight of 800 to 4,000. 12 (Lactone) polyols, polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 800 to 5,000, and polyester polyols with an average functionality of 2 to 5 and a molecular weight of 800 to 5,000.

[0046] As used herein, the term "branched aliphatic polyol comprising at least two hydroxyl groups" refers to an aliphatic polyol having at least two hydroxyl groups and at least two "branched groups" selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, and hexyl. For example, a C2-C... 16 Aliphatic polyols can be ethylene glycol, propylene glycol, butanediol, pentanediol, or hexanediol substituted with two, three, four, five, or six "branched groups" selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, and hexyl groups. According to a preferred embodiment of this application, the branched aliphatic polyol disclosed herein is trimethylpentanediol, such as 2,2,4-trimethylpentane-1,3-diol (TMPD).

[0047] According to one embodiment of this disclosure, the aforementioned polycarbonate polyol has a hydroxyl functionality of 2 to 5, such as 2 to 4, or 2 to 3, or about 2. According to another embodiment of this disclosure, the aforementioned polycarbonate polyol has an Mn of 400 to 5,000, such as 800 to 4,500, or within a numerical range obtained by combining any two of the following values: 400 g / mol, 500 g / mol, 600 g / mol, 700 g / mol, 800 g / mol, 900 g / mol, 1,000 g / mol, 1100 g / mol, 1200 g / mol, 1300 g / mol, 1400 g / mol, 1500 g / mol, 1600 g / mol, 1700 g / mol, 1800 g / mol, 1900 g / mol, 2000 g / mol, 2100 g / mol, 2200 g / mol, 2300 g / mol, 2 400g / mol, 2500g / mol, 2600g / mol, 2700g / mol, 2800g / mol, 2900g / mol, 3000g / mol, 3100g / mol, 3200g / mol, 3300g / mol, 3400g / mol, 3500g / mol, 3600g / mol, 3700g / mol, 3800g / mol, 3900g / mol, 4000g / mol, 4100g / mol, 4200g / mol, 4300g / mol, 4400g / mol, 4500g / mol, 4600g / mol, 4700g / mol, 4800g / mol, 4900g / mol, 5000g / mol.

[0048] According to one embodiment of this disclosure, the first polyol comprises the aforementioned C4-C4 group. 16 Any one or a combination of branched aliphatic polyols and polycarbonate polyols.

[0049] According to another embodiment of this disclosure, the first polyol comprises the above-mentioned C4-C... 16 Branched aliphatic polyols, and also containing poly(C4-C) polyols with an average molecular weight (Mn) of 800 to 4,000. 12 The first polyol comprises one or more of the following: a polyol containing a lactone, a polyether polyol having an average functionality of 2 to 5 and an average molecular weight of 400 to 5,000, and a polyester polyol having an average functionality of 2 to 5 and a molecular weight of 800 to 4,000. According to another embodiment of this disclosure, the first polyol comprises the aforementioned polycarbonate polyol and further comprises a poly(C4-C) polyol having an average molecular weight of 800 to 4,000. 12 One or more of the following: lactone polyols, polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 400 to 5,000, and polyester polyols with an average functionality of 2 to 5 and a molecular weight of 800 to 4,000.

[0050] In the above implementation scheme, C4-C 16 The amount of branched aliphatic polyol may be from 2% to 30% by weight of the total weight of the first polyol, such as 3% to 20% by weight, or up to 15% by weight, or up to 10% by weight, or up to 5% by weight. In the above embodiments, the amount of the "polycarbonate polyol" may be from 10% to 50% by weight of the total weight of the first polyol, such as 15% to 45% by weight, or 20% to 40% by weight, or 25% to 35% by weight.

[0051] The aforementioned polyether polyols are addition polymerization and grafting products of ethylene oxide, propylene oxide, tetrahydrofuran, and butane oxide, condensation products of polyols, and any combination thereof. Suitable examples of polyether polyols include, but are not limited to, polypropylene glycol (PPG), polyethylene glycol (PEG), polybutane glycol, polytetramethylene ether glycol (PTMEG), and any combination thereof. Preferably, the polyether polyol is a combination of PEG and at least one other polyether polyol selected from the aforementioned addition polymerization and grafting products and condensation products. More preferably, the polyether polyol is a combination of PEG and at least one of PPG, polybutane glycol, and PTMEG. According to one embodiment of this disclosure, the Mn of the aforementioned polyether polyol is from 400 to 12,000, such as 800 to 5,000, or within a numerical range obtained by combining any two of the following values: 400 g / mol, 500 g / mol, 600 g / mol, 700 g / mol, 800 g / mol, 900 g / mol, 1,000 g / mol, 1100 g / mol, 1200 g / mol, 1300 g / mol, 1400 g / mol. g / mol, 1500g / mol, 1600g / mol, 1700g / mol, 1800g / mol, 1900g / mol, 2000g / mol, 2100g / mol, 2200g / mol , 2300g / mol, 2400g / mol, 2500g / mol, 2600g / mol, 2700g / mol, 2800g / mol, 2900g / mol, 3000g / mol, 3100 g / mol, 3200g / mol, 3300g / mol, 3400g / mol, 3500g / mol, 3600g / mol, 3700g / mol, 3800g / mol, 3900g / mol , 4000g / mol, 4100g / mol, 4200g / mol, 4300g / mol, 4400g / mol, 4500g / mol, 4600g / mol, 4700g / mol, 4800 The available polyether polyols are 4900 g / mol, 5000 g / mol, 5500 g / mol, 6000 g / mol, 6500 g / mol, 7000 g / mol, 7500 g / mol, 8000 g / mol, 8500 g / mol, 9000 g / mol, 9500 g / mol, 10000 g / mol, 10500 g / mol, 11000 g / mol, 11500 g / mol, and 12000 g / mol. According to one embodiment of this disclosure, the amount of the above polyether polyols can be 0-50% by weight, or up to 40% by weight, or up to 30% by weight, or up to 20% by weight, or up to 10% by weight of the total weight of the first polyol.

[0052] Examples of the aforementioned polyester polyols are condensation products of diols and dicarboxylic acids and their derivatives, or derivatives thereof. Suitable examples of diols are ethylene glycol, butanediol, diethylene glycol, triethylene glycol, polyalkylene glycols such as polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, and any combination thereof. To achieve a polyol functionality greater than 2, triols and / or tetraols may also be used. Suitable examples of such triols include trimethylolpropane and glycerol. Suitable examples of such tetraols include erythritol and pentaerythritol. Dicarboxylic acids are selected from aromatic acids, aliphatic acids, and combinations thereof. Suitable examples of aromatic acids are phthalic acid, isophthalic acid, and terephthalic acid; while suitable examples of aliphatic acids are adipic acid, azelaic acid, sebacic acid, glutaric acid, tetrachlorophthalic acid, maleic acid, fumaric acid, itaconic acid, malonic acid, octanoic acid, 2-methylsuccinic acid, 3,3-diethylglutaric acid, and 2,2-dimethylsuccinic acid. Anhydrides of these acids can also be used. For the purposes of this invention, anhydrides are therefore encompassed by the term "acid." Preferably, the fatty acids and aromatic acids are saturated and are adipic acid and isophthalic acid, respectively. Monocarboxylic acids, such as benzoic acid and hexanecarboxylic acid, should be minimized or excluded as much as possible. According to one embodiment of this disclosure, the Mn of the aforementioned polyether polyol is from 500 to 5,000, such as from 800 to 4,000, or within a numerical range obtained by combining any two of the following values: 500 g / mol, 600 g / mol, 700 g / mol, 800 g / mol, 900 g / mol, 1,000 g / mol, 1100 g / mol, 1200 g / mol, 1300 g / mol, 1400 g / mol, 1500 g / mol, 1600 g / mol, 1700 g / mol, 1800 g / mol, 1900 g / mol, 2000 g / mol, 2100 g / mol, 2200 g / mol, 2300 g / mol, 2400 g / mol. ol, 2500g / mol, 2600g / mol, 2700g / mol, 2800g / mol, 2900g / mol, 3000g / mol, 3100g / mol, 3200g / mol, 3300g / mol, 3400g / mol, 3500g / mol, 3600g / mol, 3700g / mo l, 3800g / mol, 3900g / mol, 4000g / mol, 4100g / mol, 4200g / mol, 4300g / mol, 4400g / mol, 4500g / mol, 4600g / mol, 4700g / mol, 4800g / mol, 4900g / mol, 5000g / mol.According to one embodiment of this disclosure, the amount of the aforementioned polyester polyol may be 0-55% by weight or 20-50% by weight of the total weight of the first polyol.

[0053] The aforementioned polylactone polyols refer to those produced by at least one C4-C... 12 Polymeric polyols prepared by addition polymerization of lactones with diols, triols, and / or tetraols. Suitable examples of lactones include propiolactone, caprolactone, butyllactone, and valproicol, such as ε-caprolactone, β-propiolactone, γ-butyllactone, methyl-ε-caprolactone, or mixtures thereof. Suitable examples of diols are ethylene glycol, butanediol, diethylene glycol, triethylene glycol, polyalkylene glycols such as polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, and any combination thereof. Suitable examples of triols include trimethylolpropane and glycerol. Suitable examples of tetraols include erythritol and pentaerythritol. According to one embodiment of this disclosure, the Mn of the aforementioned polylactone polyol is from 500 to 5,000, such as from 800 to 4,000, or within a numerical range obtained by combining any two of the following values: 500 g / mol, 600 g / mol, 700 g / mol, 800 g / mol, 900 g / mol, 1,000 g / mol, 1100 g / mol, 1200 g / mol, 1300 g / mol, 1400 g / mol, 1500 g / mol, 1600 g / mol, 1700 g / mol, 1800 g / mol, 1900 g / mol, 2000 g / mol, 2100 g / mol, 2200 g / mol, 2300 g / mol, 2400 g / mol. mol, 2500g / mol, 2600g / mol, 2700g / mol, 2800g / mol, 2900g / mol, 3000g / mol, 3100g / mol, 3200g / mol, 3300g / mol, 3400g / mol, 3500g / mol, 3600g / mol, 3700g / mo l, 3800g / mol, 3900g / mol, 4000g / mol, 4100g / mol, 4200g / mol, 4300g / mol, 4400g / mol, 4500g / mol, 4600g / mol, 4700g / mol, 4800g / mol, 4900g / mol, 5000g / mol. According to one embodiment of this disclosure, the amount of the aforementioned polylactone polyol may be 0-40% by weight or 0-35% by weight of the total weight of the first polyol.

[0054] Based on the total solid weight of the first polyurethane contained in the first polyurethane dispersion, the total amount of the first polyol can be from 40 wt% to 75 wt%, such as within the numerical range obtained by combining any two of the following endpoint values: 40 wt%, 41 wt%, 42 wt%, 43 wt%, 44 wt%, 45 wt%, 46 wt%, 47 wt%, 48 wt%, 49 wt%, 50 wt%, 51 wt%, 52 wt%, 53 wt%, 54 wt%, 55 wt%, 56 wt%, 57 wt%, 58 wt%, 59 wt%, 60 wt%, 61 wt%, 62 wt%, 63 wt%, 64 wt%, 65 wt%, 66 wt%, 67 wt%, 68 wt%, 69 wt%, 70 wt%, 71 wt%, 72 wt%, 73 wt%, 74 wt%, 75 wt%.

[0055] According to a preferred embodiment of this disclosure, a polycarbonate polyol, a polylactone polyol, and a polyester polyol, as described above, are combined as the first polyol for preparing the first polyurethane. Preferably, the weight ratio between these polyols can be polycarbonate polyol:polylactone polyol:polyester polyol = (0.3-3):(0.3-3):(0.3-3), such as (0.7-1.5):(0.7-1.5):(0.7-1.5), or (0.75-1.4):(0.75-1.4):(0.75-1.4). According to a preferred embodiment, the first polyol is a blend of a polycarbonate polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000, a polylactone polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000, and a polyester polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000.

[0056] According to another preferred embodiment of this disclosure, a C4-C as described above... 16 A combination of a branched aliphatic polyol, a polyester polyol, and a polyether polyol is used as the first polyol for preparing the first polyurethane. Preferably, the weight ratio between these polyols can be C4-C5. 16 Branched aliphatic polyol: polyester polyol: polyether polyol = (0.05-5):(5-20):(5-20), such as (0.08-3):(7-15):(7-15), or (0.9-1.5):(8-12):(8-12), or (0.95-1.1):(9-11):(9-11). According to a preferred embodiment, the first polyol is a blend of trimethylpentanediol, a polyester polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000, and a polyether polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000.

[0057] The first internal emulsifier used to prepare the first polyurethane is preferably anionic. Suitable examples of the first internal emulsifier are selected from the group consisting of: C2-C molecules substituted with at least two hydroxyl or amino groups. 16 Aliphatic acids or their salts, C5-C substituted with at least two hydroxyl or amino groups 16 Alicyclic acids or their salts, sulfonates, phosphates, carboxylates, and any combination thereof. Preferably, the first internal emulsifier comprises 2,2-dimethylolpropionic acid and its derivatives.

[0058] Based on the total solid weight of the first polyurethane contained in the first polyurethane dispersion, the amount of the first internal emulsifier can be from 1 wt% to 15 wt%, such as within a numerical range obtained by combining any two of the following endpoint values: 1 wt%, 1.2 wt%, 1.4 wt%, 1.5 wt%, 1.8 wt%, 2 wt%, 2.2 wt%, 2.4 wt%, 2.5 wt%, 2.8 wt%, 3 wt%, 3.2 wt%, 3.4 wt%, 3.5 wt%, 3.6 wt%, 3.8 wt%, 4.0 wt%, 4.2 wt%, 4.5 wt%, 4.8 wt%, 5.0 wt%, 5.2 wt%, 5.5 wt%, 5.8 wt%, 6.0 wt%, 6.2 wt%, 6.5 wt%, 6.8 wt%. %, 7.0 wt%, 7.2 wt%, 7.5 wt%, 7.8 wt%, 8.0 wt%, 8.2 wt%, 8.5 wt%, 8.8 wt%, 9.0 wt%, 9.2 wt%, 9.5 wt%, 9.8 wt%, 10.0 wt%, 10.5 wt%, 11 wt%, 11.2 wt%, 11.4 wt%, 11.5 wt%, 11.8 wt%, 12 wt%, 12.2 wt%, 12.4 wt%, 12.5 wt%, 12.8 wt%, 13 wt%, 13.2 wt%, 13.4 wt%, 13.5 wt%, 13.6 wt%, 13.8 wt%, 14.0 wt%, 14.2 wt%, 14.5 wt%, 14.8 wt%, 15.0 wt%.

[0059] According to one embodiment of this disclosure, at least one chain extender or crosslinker may be present in the reactants used to prepare the first polyurethane dispersion. The chain extender or crosslinker may be a chemical having two isocyanate reactive groups per molecule and an equivalent weight of less than 300, preferably less than 200, and particularly 31 to 125 per isocyanate reactive group. The isocyanate reactive group is preferably hydroxyl, aliphatic or aromatic primary hydroxyl / amino, or aliphatic or aromatic secondary hydroxyl / amino. Representative chain extenders or crosslinkers include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, cyclohexanediol, ethylenediamine, phenylenediamine, bis(3-chloro-4-aminophenyl)methane, dimethylthiotoluenediamine, and diethyltoluenediamine.

[0060] According to one embodiment of this disclosure, based on the total solid weight of the first polyurethane contained in the first polyurethane dispersion, the content of the chain extender or crosslinker can be from 2 wt% to 12 wt%, such as within a numerical range obtained by combining any two of the following endpoint values: 2 wt%, 2.2 wt%, 2.4 wt%, 2.5 wt%, 2.8 wt%, 3 wt%, 3.2 wt%, 3.4 wt%, 3.5 wt%, 3.6 wt%, 3.8 wt%, 4.0 wt%, 4.2 wt%, 4.5 wt%, 4.8 wt%, 5.0 wt%, 5.2 wt%. wt%, 5.5 wt%, 5.8 wt%, 6.0 wt%, 6.2 wt%, 6.5 wt%, 6.8 wt%, 7.0 wt%, 7.2 wt%, 7.5 wt%, 7.8 wt%, 8.0 wt%, 8.2 wt%, 8.5 wt%, 8.8 wt%, 9.0 wt%, 9.2 wt%, 9.5 wt%, 9.8 wt%, 10.0 wt%, 10.2 wt%, 10.5 wt%, 10.8 wt%, 11.0 wt%, 11.2 wt%, 11.5 wt%, 11.8 wt%, 12.0 wt%.

[0061] The pH of the reaction mixture can be adjusted by adding an acid or a base during the preparation of the first polyurethane dispersion. Examples of bases include, but are not limited to, ammonia, diethylamine, triethylamine, dimethylethanolamine, triethanolamine, sodium hydroxide, potassium hydroxide, and sodium acetate. Examples of acids include, but are not limited to, acetic acid, formic acid, hydrochloric acid, nitric acid, and toluenesulfonic acid.

[0062] The glass transition temperature (Tg) of the first polyurethane dispersion is 5-20°C, such as within the range of values ​​obtained by combining any two of the following endpoint values: 5°C, or 6°C, or 7°C, or 8°C, or 9°C, or 10°C, or 11°C, or 12°C, or 13°C, or 14°C, or 15°C, or 16°C, or 17°C, or 18°C, or 19°C, or 20°C.

[0063] Second polyurethane dispersion

[0064] In one embodiment of this disclosure, the second polyurethane dispersion comprises a second polyurethane dispersed in water, wherein the solids content of the second polyurethane is 30% to 50% by weight, such as 32% to 49%, or 34% to 48%, or 35% to 47%, or 37% to 46%, or 38% to 45%, or 40% to 44%, or 42% to 43%, based on the total weight of the second polyurethane dispersion. Alternatively, the second polyurethane dispersion may have a solids content within a numerical range obtained by combining any two of the following percentage values: 30% by weight, 31% by weight, 32% by weight, 33% by weight, 34% by weight, 35% by weight, 36% by weight, 37% by weight, 38% by weight, 39% by weight, 40% by weight, 41% by weight, 42% by weight, 43% by weight, 44% by weight, 45% by weight, 46% by weight, 47% by weight, 48% by weight, 49% by weight, and 50% by weight.

[0065] According to one embodiment of this disclosure, the second polyurethane is in the form of fine particles. For example, the fine particles of the second polyurethane may have a particle size of 15 nm to 600 nm, or 20 nm to 500 nm, or 30 nm to 450 nm, or 50 nm to 400 nm, or 60 nm to 350 nm, or 80 nm to 300 nm, or 90 nm to 250 nm, or 100 nm to 200 nm, or 120 nm to 150 nm, or may be within a numerical range obtained by combining any two of the above endpoint values.

[0066] According to one embodiment of this disclosure, a second polyurethane is prepared by reacting at least one second monomer diisocyanate with at least one second polyol and at least one second internal emulsifier.

[0067] According to one embodiment of this disclosure, the second monomer diisocyanate may be selected from the group consisting of: C2-C 16 Aliphatic diisocyanates, C6-C 16 Aromatic diisocyanates, C5-C 16Alicyclic diisocyanates and combinations thereof. Alicyclic diisocyanates may include, but are not limited to, ethylene diisocyanate, propylene diisocyanate, butyl diisocyanate, pentamethylene diisocyanate, and hexamethylene diisocyanate (HDI). Alicyclic diisocyanates may include, but are not limited to, cyclopentyl diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate (IPDI), and methylene-bis-(4-cyclohexyl isocyanate) (HMDI). Preferred aromatic diisocyanates are selected from phenyl diisocyanate, methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), carbodiimide-modified MDI, naphthyl diisocyanate, and combinations thereof. TDI can generally be used with any commonly used isomer distribution. The most commonly used TDI isomer distribution is 80% 2,4-isomer and 20% 2,6-isomer. TDI with other isomer distributions may also be used. When MDI is used, it is preferably pure 4,4′-MDI or any combination of MDI isomers. More preferably, it is pure 4,4′-MDI and any combination of 4,4′-MDI with other MDI isomers. When using a combination of 4,4′-MDI with other MDI isomers, the preferred concentration of 4,4′-MDI is 25% to 75% of all MDI isomers. According to an alternative embodiment of this disclosure, examples of aromatic diisocyanates include, but are not limited to, isomers of methylene diphenyl diisocyanate (“MDI”) such as 4,4-MDI, 2,4-MDI and 2,2′-MDI, or modified MDIs such as carbodiimide-modified MDI or urethane-modified MDI; isomers of toluene diisocyanate (“TDI”) such as 2,4-TDI, 2,6-TDI; isomers of naphthalene diisocyanate (“NDI”) such as 1,5-NDI; and combinations thereof. In a more preferred embodiment of this disclosure, the second monomer diisocyanate may be selected from the group consisting of: 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-diisocyanodicyclohexylmethane, diisocyanomethylcyclohexane, and any combination thereof.

[0068] Based on the total solid weight of the second polyurethane contained in the second polyurethane dispersion, the amount of the second monomer diisocyanate can be from 10 wt% to 35 wt%, such as within the numerical range obtained by combining any two of the following endpoint values: 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, and 35 wt%.

[0069] According to one embodiment of this disclosure, the second monomer diisocyanate preferably has a molecular weight Mn of less than 500 g / mol, more preferably less than 300 g / mol, and even more preferably less than 275 g / mol.

[0070] According to one embodiment of this disclosure, the second polyol used to prepare the second polyurethane comprises a polyester polyol having an average functionality of 2 to 5 and a molecular weight of 600 to 6,000, and optionally further comprises a poly(C4-C5) polyol having an average molecular weight of 500 to 8,000. 12 The polyester polyol is selected from one or both of adipic acid (ADA) polyol and polyether polyol with an average functionality of 2 to 5 and an average molecular weight of 400 to 12,000. According to a preferred embodiment of this disclosure, the aforementioned polyester polyol is prepared by using one or both of hexanediol (HDO, more preferably 1,6-hexanediol) and butanediol (BDO, more preferably 1,4-butanediol).

[0071] According to one embodiment of this disclosure, the aforementioned polyester polyol has a hydroxyl functionality of 2 to 5, such as 2 to 4, or 2 to 3, or about 2. According to another embodiment of this disclosure, the aforementioned polyester polyol has an Mn of 800 to 5,000, such as 1,000 to 4,500, or within a numerical range obtained by combining any two of the following values: 800 g / mol, 900 g / mol, 1,000 g / mol, 1100 g / mol, 1200 g / mol, 1300 g / mol, 1400 g / mol, 1500 g / mol, 1600 g / mol, 1700 g / mol, 1800 g / mol, 1900 g / mol, 2000 g / mol, 2100 g / mol, 2200 g / mol, 2300 g / mol, 2400 g / mol, 2500 g / mol. , 2600g / mol, 2700g / mol, 2800g / mol, 2900g / mol, 3000g / mol, 3100g / mol, 3200g / mol, 3300g / mol, 3400g / mol, 3500g / mol, 3600g / mol, 3700g / mol, 3800 g / mol, 3900g / mol, 4000g / mol, 4100g / mol, 4200g / mol, 4300g / mol, 4400g / mol, 4500g / mol, 4600g / mol, 4700g / mol, 4800g / mol, 4900g / mol, 5000g / mol.

[0072] According to one embodiment of this disclosure, the polyester polyol is a condensation product of a diol and a dicarboxylic acid and its derivatives, or a derivative thereof. Suitable examples of diols are 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, and any combination thereof. The dicarboxylic acid is selected from aromatic acids, aliphatic acids, and combinations thereof. Suitable examples of aromatic acids are phthalic acid, isophthalic acid, and terephthalic acid; while suitable examples of aliphatic acids are adipic acid, azelaic acid, sebacic acid, glutaric acid, tetrachlorophthalic acid, maleic acid, fumaric acid, itaconic acid, malonic acid, octanoic acid, 2-methylsuccinic acid, 3,3-diethylglutaric acid, and 2,2-dimethylsuccinic acid. Anhydrides of these acids can also be used. For the purposes of this invention, anhydrides are therefore covered by the term "acid". Preferably, the fatty acid and aromatic acid are saturated and are adipic acid and isophthalic acid, respectively. Monocarboxylic acids, such as benzoic acid and hexanecarboxylic acid, should be minimized or excluded as much as possible. According to a preferred embodiment, a majority, such as at least 90%, or at least 95%, or at least 99%, or all of the polyester polyol used as the second polyol has a “linear structure.” As used herein, the term “linear polyester polyol” refers to a polyester polyol derived from one or more carboxylic acids and one or more diols without any side chains or branched structures.

[0073] According to one embodiment of this disclosure, the amount of polyester polyol can be from 35% to 100% by weight of the total weight of the second polyol, such as at least 40% by weight, or at least 50% by weight, or at least 60% by weight, or at least 70% by weight, or at least 80% by weight, or at least 85% by weight.

[0074] According to one embodiment of this disclosure, polyether polyols and polylactone polyols may optionally be used in the second polyol. According to a preferred embodiment, a majority, such as at least 90%, at least 95%, at least 99%, or all, of the polyether polyols and polylactone polyols used in the second polyol has a “linear structure.” As used herein, the terms “linear polyether polyol” and “linear polylactone polyol” refer to polyether polyols and polylactone polyols without any side chains or branched structures. Preferably, the second polyol does not contain polycarbonate polyols or C2-C... 16 Aliphatic polyols, and specifically, those that do not contain C4-C. 16 Branched-chain aliphatic polyols.

[0075] According to one embodiment of this disclosure, the amount of the optional polyether polyol may be 0-50% by weight, or up to 40% by weight, or up to 30% by weight, or up to 20% by weight, or up to 15% by weight of the total weight of the second polyol. According to another embodiment of this disclosure, the amount of the optional polylactone polyol may be 0-40% by weight, or up to 40% by weight, or up to 30% by weight, or up to 20% by weight, or up to 15% by weight of the total weight of the second polyol. The aforementioned polyether polyol and polylactone polyol used in the first polyol may be used as optional components in the second polyol.

[0076] According to a preferred embodiment of this disclosure, based on the total solid weight of the second polyurethane contained in the second polyurethane dispersion, the total amount of the second polyol can be from 50 wt% to 75 wt%, such as within the numerical range obtained by combining any two of the following endpoint values: 50 wt%, 51 wt%, 52 wt%, 53 wt%, 54 wt%, 55 wt%, 56 wt%, 57 wt%, 58 wt%, 59 wt%, 60 wt%, 61 wt%, 62 wt%, 63 wt%, 64 wt%, 65 wt%, 66 wt%, 67 wt%, 68 wt%, 69 wt%, 70 wt%, 71 wt%, 72 wt%, 73 wt%, 74 wt%, and 75 wt%.

[0077] According to a preferred embodiment of this disclosure, a polyester polyol as described above is specifically used as a second polyol for preparing a second polyurethane. According to another preferred embodiment of this disclosure, a polyester polyol as described above is combined with a polyether polyol as described above as a second polyol for preparing a second polyurethane.

[0078] The second internal emulsifier used in the preparation of the second polyurethane is preferably anionic. Suitable examples of the second internal emulsifier are selected from the group consisting of: C2-C molecules substituted with at least two hydroxyl or amino groups. 16 Aliphatic acids or their salts, C5-C substituted with at least two hydroxyl or amino groups 16 Alicyclic acids or their salts, sulfonates, phosphates, carboxylates, and any combination thereof. Preferably, the second internal emulsifier comprises 2,2-dimethylolpropionic acid and its derivatives.

[0079] Based on the total solid weight of the second polyurethane contained in the second polyurethane dispersion, the amount of the second internal emulsifier can be from 2 wt% to 10 wt%, such as within the numerical range obtained by combining any two of the following endpoint values: 2 wt%, 2.2 wt%, 2.4 wt%, 2.5 wt%, 2.8 wt%, 3 wt%, 3.2 wt%, 3.4 wt%, 3.5 wt%, 3.6 wt%, 3.8 wt%, 4.0 wt%, 4.2 wt%. 4.5 wt%, 4.8 wt%, 5.0 wt%, 5.2 wt%, 5.5 wt%, 5.8 wt%, 6.0 wt%, 6.2 wt%, 6.5 wt%, 6.8 wt%, 7.0 wt%, 7.2 wt%, 7.5 wt%, 7.8 wt%, 8.0 wt%, 8.2 wt%, 8.5 wt%, 8.8 wt%, 9.0 wt%, 9.2 wt%, 9.5 wt%, 9.8 wt%, and 10.0 wt%.

[0080] According to one embodiment of this disclosure, at least one chain extender or crosslinking agent may be present in the reactants used to prepare the second polyurethane dispersion. The types and amounts of chain extenders or crosslinking agents indicated above for the first polyurethane also apply to those for the second polyurethane.

[0081] The pH of the reaction mixture can be adjusted by adding an acid or a base during the preparation of the first polyurethane dispersion. Examples of bases include, but are not limited to, ammonia, diethylamine, triethylamine, dimethylethanolamine, triethanolamine, sodium hydroxide, potassium hydroxide, and sodium acetate. Examples of acids include, but are not limited to, acetic acid, formic acid, hydrochloric acid, nitric acid, and toluenesulfonic acid.

[0082] The glass transition temperature (Tg) of the second polyurethane dispersion is -40°C to -60°C, such as within the range of values ​​obtained by combining any two of the following endpoint values: -60°C, or -58°C, or -56°C, or -55°C, or -54°C, or -53°C, or -52°C, or -51°C, or -50°C, or -49°C, or -48°C, or -47°C, or -46°C, or -45°C, or -44°C, or -43°C, or -42°C, or -41°C, or -40°C.

[0083] acrylic emulsions

[0084] Acrylic latexes are latexes that are aqueous dispersions of particles derived from copolymers of at least one (meth)acrylic monomer and at least one styrene monomer. The copolymer may also contain additional comonomers besides the (meth)acrylic monomer and styrene monomer, which may include, for example, vinyl groups (e.g., acetates, such as vinyl acetate, ethylene-vinyl acetate; alcohols; chlorides, such as polyvinyl chloride, polyvinyl chloride; etc.). The latex will typically exhibit a viscosity in the range of about 10 cps to 1000 cps, and more preferably 20 cps to 500 cps, at 25°C. Based on the total weight of the polyacrylic emulsion, the acrylic emulsion may have a solids content in the range of 35-65%, such as a numerical range obtained by combining any two of the following endpoint values: 35 wt%, 38 wt%, 40 wt%, 42 wt%, 44 wt%, 45 wt%, 46 wt%, 48 wt%, 50 wt%, 52 wt%, 54 wt%, 55 wt%, 57 wt%, 58 wt%, 60 wt%, 61 wt%, 62 wt%, 63 wt%, 64 wt%, and 65 wt%. In one embodiment, the copolymer in the polyacrylic emulsion may have a number average molecular weight between 5,000 and 2,000,000, and more preferably between 100,000 and 2,000,000.

[0085] According to one embodiment of this disclosure, based on the total solids weight of the polyacrylic emulsion, the copolymer may contain 5% to 50% by weight of repeating units derived from at least one styrene monomer. Alternatively, based on the total solids weight of the polyacrylic emulsion, the content of polymeric residues derived from at least one styrene monomer may be within a numerical range obtainable by combining any two of the following endpoint values: 5% by weight, 8% by weight, 10% by weight, 12% by weight, 15% by weight, 18% by weight, 20% by weight, 22% by weight, 25% by weight, 28% by weight, 30% by weight, 32% by weight, 35% by weight, 38% by weight, 40% by weight, 42% by weight, 44% by weight, 45% by weight, 48% by weight, and 50% by weight. The styrene monomer may include styrene or C1-C6 alkyl-substituted styrene, such as styrene or α-methylstyrene.

[0086] According to a preferred embodiment of this disclosure, based on the total solids weight of the polyacrylic emulsion, the copolymer may contain 50% to 90% by weight of derivatives of at least one C1-C. 20 Polymer residues of alkyl (meth)acrylate monomers, and optionally, 1% to 15% by weight of repeating units derived from at least one olefinic unsaturated acid having at least one carboxylic acid group.

[0087] For example, based on the total solids weight of polyacrylic emulsions, derived from at least one C1-C 20 The content of repeating units of alkyl (meth)acrylate monomers can be within a numerical range obtainable by combining any two of the following endpoint values: 50 wt%, 52 wt%, 55 wt%, 58 wt%, 60 wt%, 62 wt%, 65 wt%, 68 wt%, 70 wt%, 72 wt%, 75 wt%, 78 wt%, 80 wt%, 82 wt%, 85 wt%, 88 wt%, and 90 wt%. According to one embodiment of this disclosure, C1-C 20 Alkyl (meth)acrylate monomers can be C4-C 12 Alkyl (meth)acrylate monomers, such as methyl methacrylate (MMA), ethyl methacrylate (EMA), butyl methacrylate (BMA), ethylhexyl methacrylate (EHMA), lauryl methacrylate (LMA), hydroxyethyl methacrylate (HEMA), methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), isobutyl acrylate (IBA), ethylhexyl acrylate (EHA), and hydroxyethyl acrylate (HEA).

[0088] Based on the total solids weight of the polyacrylic emulsion, the content of repeating units derived from at least one olefinic unsaturated acid can be within a numerical range obtainable by combining any two of the following endpoint values: 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, and 15 wt%. According to one embodiment of this disclosure, the olefinic unsaturated acid can be acrylic acid, methacrylic acid, itaconic acid, fumaric acid, or combinations thereof.

[0089] According to one embodiment of this disclosure, the copolymer in the polyacrylic emulsion contains less than 0.5% hydroxyl-containing monomer residues. Preferably, the polymer has less than 0.3% of such residues, more preferably less than 0.2%, and most preferably, the polymer is substantially free of hydroxyl-containing monomer residues. Examples of hydroxyl-containing monomers include, for example, HEMA, HEA, vinyl alcohol, hydroxypropyl methacrylate (HPMA), and hydroxypropyl acrylate. Preferably, the polymer is substantially free of amino-containing monomers. Preferably, the polymer has less than 0.5% of isocyanate reactive groups other than carboxylic acid groups, more preferably less than 0.2%, and most preferably, the polymer is substantially free of isocyanate reactive groups other than carboxylic acid groups.

[0090] Common processing agents such as surfactants and initiators can be used to prepare polyacrylic acid emulsions. For example, surfactants can be used in the preparation of polyacrylic acid emulsions to provide stability and control particle size. Conventional surfactants include anionic or nonionic emulsifiers or combinations thereof. Typical anionic emulsifiers include, but are not limited to, alkyl sulfates or ammonium, alkyl ether sulfates or ammonium, alkyl aryl ether sulfates or ammonium, alkyl sulfonates, fatty acid salts, esters of sulfosuccinates, alkyl diphenyl ether disulfonates, and salts or free acids of complex organophosphates. Typical nonionic emulsifiers include, but are not limited to, polyethers, such as ethylene oxide and propylene oxide condensates, including straight-chain and branched alkyl and alkyl aryl polyethylene glycol and polypropylene glycol ethers and thioethers, alkylphenoxy poly(ethyleneoxy)ethanol with alkyl groups containing about 7 to about 18 carbon atoms and having about 4 to about 100 ethyleneoxy units, and polyoxyethylene derivatives of hexyl alcohols, including sorbitol, sorbitan, mannan, and mannitol anhydride. Based on the total weight of the resulting polyacrylic emulsion, the surfactant can be used at a level of 0.1% to 5% by weight.

[0091] According to one embodiment of this disclosure, the Tg of the acrylic emulsion is from -40°C to -20°C, such as within a numerical range obtained by combining any two of the following endpoint values: -40°C, or -39°C, or -38°C, or -37°C, or -36°C, or -35°C, or -34°C, or -33°C, or -32°C, or -31°C, or -30°C, or -29°C, or -28°C, or -27°C, or -26°C, or -25°C, or -24°C, or -23°C, or -22°C, or -21°C, or -20°C.

[0092] Other additives

[0093] Optionally, one or more catalysts may be used to promote or accelerate the polymerization reactions described above for preparing the first and second polyurethane dispersions. The catalyst may include any substance capable of promoting the reaction between the isocyanate group and the hydroxyl group. Without being theoretically limited, the catalyst may include, for example, glycinate salts; tertiary amines; tertiary phosphines, such as trialkylphosphine and dialkylbenzylphosphine; morpholine derivatives; piperazine derivatives; chelates of various metals, such as those obtainable from acetylacetone, benzoylacetone, trifluoroacetylacetone, ethyl acetoacetate, etc., with metals such as Be, Mg, Zn, Cd, Pd, Ti, Zr, Sn, As, Bi, Cr, Mo, Mn, Fe, Co, and Ni; acidic metal salts of strong acids, such as ferric chloride and tin chloride; and salts of organic acids with various metals, such as alkali metals and alkaline earth metals. Al, Sn, Pb, Mn, Co, Ni, and Cu; organotin compounds, such as tin(II) salts of organic carboxylic acids, such as tin(II) diacetate, tin(II) dioctanoate, tin(II) diethylhexanoate, and tin(II) dilaurate, and dialkyltin(IV) salts of organic carboxylic acids, such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and dioctyltin diacetate; bismuth salts of organic carboxylic acids, such as bismuth octanoate; organometallic derivatives of trivalent and pentavalent As, Sb, and Bi, and carbonyl metals of iron and cobalt; or mixtures thereof. Typically, the catalyst used herein is present in an amount greater than zero and at most 1.0% by weight, preferably at most 0.5% by weight, more preferably at most 0.05% by weight, based on the total weight of all reactants. According to another embodiment of this disclosure, either or both of the first and second polyurethane dispersions are prepared without the use of a catalyst.

[0094] The coating compositions disclosed herein may optionally contain any additional additives and / or auxiliaries for a particular purpose. In one embodiment of this disclosure, the additives and / or auxiliaries are selected from the group consisting of: tackifiers, plasticizers, rheology modifiers, antioxidants, fillers, colorants, pigments, water removers, surfactants, solvents, diluents, flame retardants, antislip agents, antistatic agents, preservatives, biocides, antioxidants, and combinations of two or more thereof.

[0095] Waterborne coating composition

[0096] According to one embodiment of this application, the weight ratio of the first polyurethane dispersion, the second polyurethane dispersion, and the polyacrylic emulsion can be (10-15):(1-7):(1-8).

[0097] According to one embodiment of this disclosure, the relative content of the first polyurethane dispersion can be from 50 parts by weight to 75 parts by weight, such as within the range of values ​​obtained by any two of the following endpoint values: 50 parts by weight, 51 parts by weight, 52 parts by weight, 53 parts by weight, 54 parts by weight, 55 parts by weight, 56 parts by weight, 57 parts by weight, 58 parts by weight, 59 parts by weight, 60 parts by weight, 61 parts by weight, 62 parts by weight, 63 parts by weight, 64 parts by weight, 65 parts by weight, 66 parts by weight, 67 parts by weight, 68 parts by weight, 69 parts by weight, 70 parts by weight, 71 parts by weight, 72 parts by weight, 73 parts by weight, 74 parts by weight, and 75 parts by weight.

[0098] According to another embodiment of this disclosure, the relative content of the second polyurethane dispersion can be from 10 parts by weight to 25 parts by weight, such as within the range of values ​​obtained by any two of the following endpoint values: 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight, 19 parts by weight, 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, and 25 parts by weight.

[0099] According to another embodiment of this disclosure, the relative content of the polyacrylic emulsion can be from 5 parts by weight to 40 parts by weight, such as within the range of values ​​obtained by any two of the following endpoint values: 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight, 19 parts by weight, 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, 25 parts by weight, 26 parts by weight, 27 parts by weight, 28 parts by weight, 29 parts by weight, 30 parts by weight, 31 parts by weight, 32 parts by weight, 33 parts by weight, 34 parts by weight, 35 parts by weight, 36 parts by weight, 37 parts by weight, 38 parts by weight, 39 parts by weight, and 40 parts by weight.

[0100] It should be understood that the contents of the first polyurethane dispersion, the second polyurethane dispersion, and the polyacrylic emulsion are calculated in parts by weight rather than weight percentages, therefore the total contents of these three components may not necessarily be 100.

[0101] PTP Sheets

[0102] According to one embodiment of this disclosure, the aqueous coating composition of this disclosure can be used to bond at least two different layers together to form a laminated material, such as a PTP (pressure-penetration packaging) sheet for medical packs. According to one example of this disclosure, the PTP sheet comprises a container film and a cover film, the container film having a recessed pouch portion filled with contents (such as tablets), the cover film being attached to the container film, for example, to seal an opening in the recessed pouch portion. The container film can be made of various polymers, such as polymethyl methacrylate, polypropylene carbonate, polybutene carbonate, polystyrene, acrylonitrile-butadiene-styrene resin, acrylic resins, polyvinyl chloride, polyvinyl alcohol, polycarbonate, polyethylene terephthalate, polyurethane, polyimide, and copolymers thereof, and is preferably a transparent resin material, while the cover film can be made of metal foil, such as aluminum foil and aluminum alloy foil.

[0103] The aqueous coating composition of this disclosure can be applied to the surface of a cover film, then dried and / or cured to form an adhesive layer, and then the container film is pressed onto the exposed surface of the adhesive layer under elevated temperature and pressure to form a PTP sheet, thereby encapsulating a drug (e.g., a tablet) within a recessed pouch portion.

[0104] Example

[0105] Some embodiments of the invention will now be described in the following examples, wherein all parts and percentages are by weight unless otherwise stated. However, the scope of this disclosure is certainly not limited to the formulations described in these examples. Rather, the examples are merely illustrative of this disclosure.

[0106] Table 1. Raw Material Information

[0107]

[0108]

[0109] Preparation Example 1: Preparation of the first polyurethane dispersion (PUD-1)

[0110] 11 g of Desmodur W was added to a mixture of 7 g Capa220, 6 g Eternacoll UP-100, 2.0 g bis-MPA, and 8 g Bester 127. The mixture was then reacted at 75°C for 4.5 hours with stirring to form a prepolymer. The prepolymer was then transferred to a plastic wide-mouth bottle, and TEA was added to the bottle with high-speed stirring (2500 rpm) for 2 minutes to neutralize the contents to a pH of approximately 7. 66 g of cold DI water (5°C) was added to the bottle with high-speed stirring to form a homogeneous oil-in-water dispersion, and 3 g of 20% aqueous EDA solution was slowly added to the dispersion while stirring at 1200 rpm for 20 minutes. The resulting dispersion was labeled PUD-1 and exhibited a Tg value of 10°C.

[0111] Preparation Example 2: Preparation of the first polyurethane dispersion (PUD-2)

[0112] 12.5 g of Desmodur W was added to a mixture of 10.0 g PTMEG2000, 10.5 g Bester 127, 1.0 g TMPD, and 3 g bis-MPA. The mixture was then reacted at 80 °C for 4 h to form a prepolymer. The prepolymer was then transferred to a plastic wide-mouth bottle, and TEA was added to the bottle with high-speed stirring (2500 rpm) for 2 minutes to neutralize the contents to approximately pH 7. 64.5 g of cold DI water (5 °C) was added to the bottle with high-speed stirring to form a homogeneous oil-in-water dispersion, and 4.5 g of an aqueous EDA solution (20%) was slowly added to the dispersion while stirring at 1200 rpm for 20 minutes. The resulting dispersion was labeled PUD-2 and exhibited a Tg value of 15 °C.

[0113] Preparation Example 3: Preparation of the Second Polyurethane Dispersion (PUD-3)

[0114] 13 g of Vestanat IPDI was added to a mixture of 33.5 g Bester 80 and 2.5 g of bis-MPA. The mixture was then reacted at 70 °C for 4.5 h to form a prepolymer. The prepolymer was then transferred to a plastic wide-mouth bottle, and TEA was added to the bottle with high-speed stirring (2500 rpm) for 2 minutes to neutralize the contents to a pH of approximately 7. 51 g of cold DI water (5 °C) was added to the bottle with high-speed stirring to form a homogeneous oil-in-water dispersion, and 4.8 g of an aqueous EDA solution (20%) was slowly added to the dispersion while stirring at 1200 rpm for 20 minutes. The resulting dispersion was labeled PUD-3 and exhibited a Tg value of -47 °C.

[0115] Preparation Example 4: Preparation of the Second Polyurethane Dispersion (PUD-4)

[0116] Add 12.0g Desmodur W to 30g Bester 121, 1.0g Bis-MPA, and 5.0g Voranol. TM The mixture of PEG1000 was then reacted at 85°C for 4 hours to form a prepolymer. The prepolymer was then transferred to a plastic wide-mouth bottle, and TEA was added to the bottle with high-speed stirring (2500 rpm) for 2 minutes to neutralize the contents to approximately pH 7. 52 g of cold DI water (5°C) was added to the bottle with high-speed stirring to form a homogeneous oil-in-water dispersion, and 4.0 g of an aqueous EDA solution (20%) was slowly added to the dispersion while stirring at 1300 rpm for 20 minutes. The resulting dispersion was labeled PUD-4 and exhibited a Tg value of -55°C.

[0117] Preparation Example 5: Preparation of the Second Polyurethane Dispersion (PUD-5)

[0118] 10 g of Vestanat IPDI was added to a mixture of 28 g Bester 121 and 2.0 g of bis-MPA. The mixture was then reacted at 70 °C for 4.5 h to form a prepolymer. The prepolymer was then transferred to a plastic wide-mouth bottle, and TEA was added to the bottle with high-speed stirring (2600 rpm) for 2 minutes to neutralize the contents to a pH of approximately 7. 60 g of cold DI water (5 °C) was added to the bottle with high-speed stirring to form a homogeneous oil-in-water dispersion, and 4.0 g of aqueous EDA solution (20%) was slowly added to the dispersion while stirring at 1400 rpm for 25 minutes. The resulting dispersion was labeled PUD-5 and exhibited a Tg value of -52 °C.

[0119] Preparation Example 6: Preparation of Polyacrylic Acid Emulsion (PAC-1)

[0120] 2.38 g of DS-4 was dissolved in 315 g of deionized water (DI water) to form a solution. 31.9 g of AA, 692.7 g of BA and 173.2 g of Sty were slowly added to the solution with stirring to form an emulsified monomer mixture.

[0121] A solution containing 5.62 g DS4 and 300 g deionized water was introduced into a 5-necked 3-liter round-bottom flask equipped with a thermocouple, a cooling condenser, and a stirrer, and heated to 84 °C under a nitrogen atmosphere. A solution of 13.7 g itaconic acid (IA) dissolved in 180 g DI water at 60 °C was added to the flask, followed by 52.5 g of the monomer emulsion described above. Then, a solution of 2.74 g ammonium persulfate (APS) in 20 g DI water was added to the flask to initiate the reaction. The temperature increased as the exothermic reaction proceeded, and when the temperature reached a peak of 84 °C, the remaining monomer emulsion and APS solution (1.18 g in 44 g DI water) were gradually added over a period of 150 minutes, during which time the temperature was maintained at 83–85 °C. After the addition was complete, the container of the monomer emulsion and the feed line to the flask were rinsed with 35 g DI water, and the rinse water was also added to the flask. The flask was kept at 84°C for another 15 minutes, then cooled to 75°C. Over 30 minutes, a solution of 3.58 g of tert-butyl hydroperoxide in 40 g of DI water and a solution of 2.29 g of isoascorbic acid in 47 g of DI water were gradually fed into the flask. The reaction was then cooled to room temperature. 19.5 g of 25% ammonia was added to the flask to adjust the pH to 6.5–7.5. The contents of the flask were then diluted with DI water to a solids content of 46% and exhibit a Tg of -30°C.

[0122] Preparation Example 7: Preparation of Polyacrylic Acid Emulsion (PAC-2)

[0123] 2.99g sodium carbonate, 4.03g DS-4 and 3.19g A-102 were dissolved in 249g deionized water to form a solution. 41.8g AA, 968.3g BA and 167.3g Sty were slowly added to the solution with stirring to form an emulsified monomer mixture.

[0124] A solution containing 2.02 g DS4 and 224 g deionized water was introduced into a 5-necked 3-liter round-bottom flask equipped with a thermocouple, a cooling condenser, and a stirrer, and heated to 84 °C under a nitrogen atmosphere. A solution of 18 g itaconic acid dissolved in 69 g of DI water at 60 °C was added to the flask, followed by 20.1 g of the aforementioned monomer emulsion. Then, a solution of 3.6 g ammonium persulfate (APS) in 15 g of DI water was added to the flask to initiate the reaction. The temperature increased as the exothermic reaction proceeded, and when the temperature reached a peak of 84 °C, the remaining monomer emulsion and APS solution (1.18 g in 44 g of DI water) were gradually added over a period of 150 minutes, during which time the temperature was maintained at 83–85 °C. At 96.7 minutes, a solution of 16.11 g DS4 in 13 g of DI water was also added to the flask. After the addition was complete, the container of the monomer emulsion and the feed tube leading to the flask were rinsed with 50 g of DI water, and the rinse water was also added to the flask. The flask was kept at 84°C for another 15 minutes, then cooled to 75°C, and over 30 minutes, a solution of 5.16 g of tert-butyl hydroperoxide in 40 g of DI water and a solution of 4.4 g of FF6 in 40 g of DI water were gradually fed into the flask, and then the flask was cooled to room temperature. 18.7 g of 25% ammonia was added to the flask to adjust the pH to 6.5–7.5. The contents of the flask were then diluted with DI water to a solids content of 57.5% and exhibit a Tg of -25°C.

[0125] Invention Examples 1-7 and Comparative Examples 1-7: Preparation of Coating Compositions

[0126] The PUD and PAC prepared above were combined according to the relative contents listed in Table 2 below to form the coating compositions of Invention Examples (IE) 1-7 and Comparative Examples (CE) 1-7.

[0127] Table 2. Formulation Information

[0128] PUD-1 PUD-2 PUD-3 PUD-4 PUD-5 PAC-1 PAC-2 IE.1 55g 15g 30g IE.2 55g 15g 30g IE.3 55g 15g 30g IE4 55g 20g 25g IE.5 50g 15g 35g IE.6 70g 20g 10g IE.7 65g 15g 20g CE.1 85g 15g CE.2 85g 15g CE.3 85g 15g CE.4 85g 15g CE.5 85g 15g CE.6 100g CE.7 100g

[0129] Each of the above coating compositions was used to produce a laminate of aluminum foil and PVC board, and its performance characteristics were characterized. The characterization results are summarized in Table 3 below:

[0130] Table 3. Performance evaluation results of Al foil / PVC

[0131]

[0132]

[0133] HSS: Heat seal strength; Aging conditions: 85°C and 85% humidity.

[0134] As can be seen from Table 3, the invention examples (IE.1-7) containing two PUDs and one polyacrylic emulsion still exhibit good heat-sealing strength and good anti-blocking properties after aging at 85°C and 85% humidity for 3 days, while the comparative examples (CE.1-7) exhibit very poor performance.

[0135] Test methods

[0136] Heat seal strength (HS)

[0137] The above-prepared coating composition was applied to one surface of an aluminum foil (100mm×100mm) at a dry coating weight of 3.2gsm. The coated aluminum foil was then heated in an oven at 150°C for 30 seconds, and then removed from the oven and cooled.

[0138] The coated foil was laminated together with a PVC board (100mm×100mm), with the exposed surface of the coating facing the PVC board. The laminate was then heat-compressed in a heat sealer at a sealing temperature of 150°C and a compression pressure of 0.2MPa for 1 second. The sample was then removed from the machine and cooled at ambient temperature for at least two hours.

[0139] Each sample was then cut into 15mm wide strips and subjected to a heat seal strength test on a tensile strength tester. Each sample was tested three times, and the average of the three tests was reported as the final result. Specifically, the PVC sheet was clamped in the upper fixture, while the aluminum foil was clamped in the lower fixture. At the start of the test, the tensile strength tester was turned on, and the two fixtures began to move in opposite directions at a speed of 200mm / min ± 20mm / min to perform a 180° peeling motion. Simultaneously, the heat seal strength value was recorded in real time on a computer. A higher value indicates better heat seal strength.

[0140] Anti-adhesion test :

[0141] The above-prepared coating composition was applied to one surface of an aluminum foil (100mm×100mm) at a dry coating weight of 3.2gsm. The coated aluminum foil was then heated in an oven at 150°C for 30 seconds, and then removed from the oven and cooled.

[0142] Four coated foils prepared above were overlapped, with the surface of each coated foil in contact with the uncoated surface of the other foil. The four-layer laminate sample was placed on a flat surface and a 1.0 kg weight was placed on top of it. The entire sample was heated in an oven at 40°C for 2 hours, and then removed to observe adhesion.

[0143] Aging test :

[0144] The heat-sealed laminate was kept in a conditioning chamber at 85°C and 85% relative humidity for 3 days, and was removed daily to monitor the heat seal strength.

[0145] Glass transition temperature (Tg)

[0146] Heat the PUD or PAC sample until dry, then transfer it to an aluminum crucible and test it using a DSC Q2000 instrument from TA Instruments according to the following procedure:

[0147] 1. Increase the temperature from -80°C to 120°C at a rate of 20°C / min to erase the thermal history;

[0148] 2. Cool the sample to -80℃;

[0149] 3. The temperature was increased from -80℃ to 120℃ at a rate of 10℃ / min to characterize the DSC plot; and

[0150] 4. Select the half-maximum transition point in the DSC chart as the glass transition temperature (Tg).

Claims

1. A water-based coating composition, said water-based coating composition comprising: (a) 50 to 75 parts by weight of a first polyurethane dispersion comprising a first polyurethane with a Tg of 5°C to 20°C. (b) 10 to 25 parts by weight of a second polyurethane dispersion comprising a second polyurethane having a Tg of -40°C to -60°C, and (c) 5 to 40 parts by weight of a polyacrylic emulsion comprising an acrylic polymer or acrylic copolymer with a Tg of -40°C to -20°C. in, The first polyurethane dispersion is prepared by reacting at least one first monomer diisocyanate with at least one first polyol and at least one first internal emulsifier; The second polyurethane is prepared by reacting at least one second monomer diisocyanate with at least one second polyol and at least one second internal emulsifier; Furthermore, the acrylic polymer or acrylic copolymer is derived from at least one acrylic monomer or methacrylic monomer and at least one styrene monomer.

2. The water-based coating composition according to claim 1, wherein... The first polyurethane is prepared by reacting 15% to 45% by weight of the first monomer diisocyanate, 40% to 75% by weight of the first polyol, and 2% to 15% by weight of the first internal emulsifier based on the total dry weight of the first polyurethane dispersion. The second polyurethane is prepared by reacting 10% to 35% by weight of the at least one second monomer diisocyanate, 50% to 75% by weight of the at least one second polyol, and 2% to 15% by weight of the at least one second internal emulsifier, based on the total dry weight of the second polyurethane dispersion; and The acrylic polymer or acrylic copolymer is prepared by reacting 60% to 90% by weight of the at least one (meth)acrylic monomer and 10% to 40% by weight of the at least one styrene monomer.

3. The waterborne coating composition according to claim 1, wherein the first monomer diisocyanate and the second monomer diisocyanate are each independently selected from the group consisting of: C2-C 16 Aliphatic diisocyanates, C6-C 16 Aromatic diisocyanates, C5-C 16 Alicyclic diisocyanates and combinations thereof.

4. The waterborne coating composition according to claim 1, wherein the first polyol comprises a C4-C group including at least two hydroxyl groups. 16 The product comprises at least one of branched aliphatic polyols and polycarbonate polyols having an average functionality of 2 to 5 and a molecular weight of 500 to 3,000, and optionally further comprises poly(C4-C) polyols having an average functionality of 2 to 5 and an average molecular weight of 800 to 4,000. 12 One or more of the following: lactone polyols, polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 800 to 5,000, and polyester polyols with an average functionality of 2 to 5 and a molecular weight of 800 to 5,000; and The second polyol comprises a polyester polyol having an average functionality of 2 to 5 and a molecular weight of 800 to 5,000, and optionally further comprises a poly(C4-C) polyol having an average functionality of 2 to 5 and an average molecular weight of 500 to 8,000. 12 One or both of the following: lactone polyols and polyether polyols with an average functionality of 2 to 5 and an average molecular weight of 400 to 12,000.

5. The waterborne coating composition according to claim 1, wherein... (A) The first polyol is selected from (a) a blend of a polycarbonate polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000, a polylactone polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000, and a polyester polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000; and (b) a blend of trimethylpentanediol, a polyester polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000, and a polyether polyol with an average functionality of 2 and a molecular weight of 1,000 to 3,000; and / or (B) The second polyol is selected from (c) a linear polyester polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000; and (d) a linear polyester polyol having an average functionality of 2 and a molecular weight of 1,000 to 3,000 and a poly(C4-C) polyol having an average functionality of 2 and an average molecular weight of 1,000 to 3,000. 12 A blend of at least one of a lactone polyol and a polyether polyol having an average functionality of 2 and an average molecular weight of 1,000 to 3,000.

6. The waterborne coating composition according to claim 1, wherein the first internal emulsifier and the second internal emulsifier are each independently selected from the group consisting of: C2-C molecules substituted with at least two hydroxyl or amino groups. 16 Aliphatic acids or their salts, C5-C substituted with at least two hydroxyl or amino groups 16 Alicyclic acids or their salts, and any combination thereof.

7. The waterborne coating composition of claim 1, wherein the acrylic copolymer of the polyacrylic emulsion is derived from a third raw material, and the third raw material comprises 60% to 80% by weight of at least one C1-C based on the total solid weight of the polyacrylic emulsion. 12 Alkyl (meth)acrylates, 1% to 10% by weight of at least one olefinic unsaturated acid, and 10% to 40% by weight of styrene and / or C1-C6 alkyl-substituted styrene.

8. The waterborne coating composition according to claim 1, wherein the weight ratio of the first polyurethane dispersion, the second polyurethane dispersion and the polyacrylic emulsion is (10-15):(1-7):(1-8).

9. A method for producing a laminated material, the method comprising: (a) Providing metal foil and substrate; (b) Applying the water-based coating composition according to any one of claims 1-8 to at least one surface of the metal foil to form a wet coating, then curing and drying the wet coating to form a dry coating; as well as (c) The substrate is laminated onto the dry coating under pressure and elevated temperature to form the laminate material.

10. A laminate comprising a metal foil, a substrate, and a coating sandwiched therebetween, wherein the coating is derived from an aqueous coating composition according to any one of claims 1-8.

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