Polyethylene resin-containing baking powder coating composition and liquid coating composition, and coating film and coated body containing baking powder coating composition or liquid coating composition

Abstract

[Problem] The purpose of the present invention is to provide: a baking powder coating composition and baking liquid coating composition which are PFAS-free, have excellent corrosion resistance and processability while also having high durability and high chemical resistance, and form a good lining coating film without causing defects such as cracks; and a coating film and coated body containing the baking powder coating composition or baking liquid coating composition. [Solution] This baking powder coating composition comprises a polyethylene resin in which a porous coordination polymer (PCP) / metal organic framework (MOF) is dispersed, wherein an organic ligand and a central metal form a coordination bond in the porous coordination polymer (PCP) / metal organic framework (MOF).

Description

Powder coating compositions and liquid coating compositions for baking containing polyethylene resin, coatings and coating bodies containing the powder coating composition or liquid coating composition for baking.

[0001] The present invention relates to a powder coating composition and a liquid coating composition for baking containing a polyethylene resin, and to a coating and a film body containing this powder coating composition or liquid coating composition. More specifically, the present invention relates to a powder coating composition and a liquid coating composition for baking containing a polyethylene resin in which porous coordination polymers (PCP) / metal-organic structures (MOFs) formed by coordination bonding between organic ligands and a central metal are dispersed, and to a coating and a film body containing this powder coating composition or liquid coating composition.

[0002] Fluoropolymers possess excellent heat resistance, corrosion resistance, water repellency, stain resistance, lubricity, and abrasion resistance, and are used as lining coatings for substrates made of metals and other materials. However, in recent years, there has been a growing trend towards avoiding the use of fluorinated compounds due to their environmental persistence, a so-called PFAS-free approach, and a need for non-fluorinated alternatives.

[0003] Patent Document 1 discloses that a highly durable lining film was obtained by adding a porous coordination polymer (PCP) / metal-organic structure (MOF) to a fluororesin.

[0004] Patent No. 6785517

[0005] However, while the invention described in Patent Document 1 enhances the functionality of fluororesins, it presents a challenge in that, from the perspective of avoiding the use of fluorine compounds, a non-fluorine alternative is needed, as is the case with PFAS-free materials.

[0006] On the other hand, polyethylene compounds have inferior chemical resistance compared to fluororesins, are insoluble in solvents, and, in particular, ultra-high molecular weight polyethylene is difficult to melt-process. For these reasons, it has been considered extremely difficult to use polyethylene resin compounds as a substitute for fluororesin compounds in paint compositions until now.

[0007] The present invention has been made in view of the problems arising from the above background, and aims to provide a powder coating composition and a liquid coating composition for baking that are PFAS-free, have excellent corrosion resistance and processability, and at the same time have high durability and chemical resistance, and form a good lining film without causing defects such as cracks, as well as a film and a film body containing this powder coating composition or liquid coating composition for baking.

[0008] The present invention relates to a baking coating composition containing polyethylene resin, wherein a porous coordination polymer (PCP) / metal-organic structure (MOF) formed by a coordination bond between an organic ligand and a central metal is dispersed in the polyethylene resin, and is a powder coating composition for baking.

[0009] Powder coatings, by using thermoplastic resins, can utilize solvent-insoluble resins, resulting in a highly solvent-resistant coating.

[0010] The porous coordination polymer (PCP) / metal-organic structure (MOF) is in powder form, and its 5% decomposition temperature from 100°C in air, as measured by thermogravimetric differential thermal analysis (TG-DTA), is higher than the melting point of the polyethylene resin, and it is blended in an amount of 0.01% to 20.00% by weight relative to the entire powder coating composition for baking.

[0011] The polyethylene resin is thermoplastic, insoluble in both polar and nonpolar solvents, and is blended in an amount of 70.00% to 99.99% by weight of the entire coating composition for baking.

[0012] The aforementioned powder coating composition for baking has excellent durability, chemical resistance, penetration resistance, and corrosion resistance, and can form a good lining film without causing defects such as cracks.

[0013] If the amount of porous coordination polymer (PCP) / metal-organic structure (MOF) is insufficient relative to the overall powder coating composition for baking, the desired sufficient durability, chemical resistance, corrosion resistance, etc., cannot be obtained. Conversely, if the amount is excessive, the coating will not form properly on the substrate.

[0014] The central metal is Al ３＋ , Co ３＋ , Co ２＋ , Ni ２＋ , Ni ＋ , Cu ２＋ , Cu ＋ , Zn ２＋ , Fe ３＋ , Fe ２＋ , Ti ３＋ , and Zr ４＋ It exists as one or more metal ions selected from the group consisting of, and the metal ions are preferably present in the porous coordination polymer (PCP) / metal organic framework (MOF) by coordinating with the organic ligand.

[0015] According to such a configuration, the pore structure changes due to the different valences of the metal ions, and it becomes possible to prepare durability, chemical resistance, corrosion resistance, heat resistance, etc. as needed.

[0016] At least one of the central metals supports one or more anions, and the central metal is preferably present in the porous coordination polymer (PCP) / metal organic framework (MOF) by coordinating with the organic ligand.

[0017] According to such a configuration, a polymer structure having a pore structure is assembled to prevent or delay the penetration of components that cause a decrease in the durability of the coating film, and a powder coating composition for baking that provides a lining coating film having excellent durability can be obtained.

[0018] The anion preferably contains one or more anions selected from the group consisting of OH － , CO ３ ２－ and O ２－ .

[0019] According to such a configuration, OH － , CO ３ ２－ , O ２－ interact with the chemical, and a powder coating composition for baking that provides a coating film with more excellent corrosion resistance and chemical resistance can be obtained.

[0020] Preferably, at least one of the central metals forms an oxo structure together with the anion.

[0021] According to this configuration, the oxo structure interacts with chemicals, making it possible to obtain a powder coating composition for baking that provides a coating with superior corrosion resistance and chemical resistance.

[0022] The organic ligand preferably includes one or more organic ligands selected from the group consisting of 1,3-benzenedicarboxylic acid, 1,4-benzenedicarboxylic acid, 1,3,5-benzenetricarboxylic acid, 4,4'-bipyridyl, imidazole, 1,3,5-tris(4-carboxyphenyl)benzene, fumaric acid, terephthalic acid, and maleic acid.

[0023] According to this configuration, a polymer structure with a porous structure is assembled, preventing and delaying the penetration of components that reduce the durability of the coating, thus enabling the creation of a lining coating with excellent durability. Furthermore, by adjusting the amount of organic ligands used, it is possible to obtain porous coordination polymers (PCPs) / metal-organic structures (MOFs) with various polymer structures.

[0024] In one embodiment of the present invention, the porous coordination polymer (PCP) / metal-organic structure (MOF) imparts gas adsorption properties to a powder coating composition for baking.

[0025] The gas may be a corrosive gas containing at least water vapor and hydrogen chloride.

[0026] Because polyethylene resin is permeable to gases, it could not provide sufficient corrosion resistance when the substrate of the polyethylene resin lining film was reactive with gases or when the durability of the primer layer that ensures adhesion between the lining film and the substrate was reduced. Porous coordination polymers (PCPs) / metal-organic structures (MOFs) adsorb gases, thus reducing the gas permeability of the polyethylene resin lining film and improving its corrosion resistance.

[0027] While polyethylene resins can be permeated by corrosive gases, potentially causing problems with film adhesion, a powder coating composition for baking is available that allows for the formation of a lining film with excellent durability, chemical resistance, penetration resistance, and corrosion resistance by using a porous coordination polymer (PCP) / metal-organic structure (MOF) to adsorb gases.

[0028] The porous coordination polymer (PCP) / metal-organic frame (MOF) has a pore area of ​​0.15 nm. ２ ~7.00 nm ２ It is preferable that this be the case.

[0029] The pore opening area is 0.15 nm ２ If the pore size is smaller, adsorption of large gas molecules becomes impossible. The pore opening area is 7.00 nm. ２ If the size is larger, the effect of capillary condensation is attenuated, and the gas adsorption properties decrease.

[0030] The porous coordination polymer (PCP) / metal-organic structure (MOF) is 900.00 m ２ It is preferable to have a specific surface area (BET specific surface area) greater than / g.

[0031] Specific surface area (BET specific surface area) is 900.00 m² ２ A value greater than / g increases the amount of gas adsorbed, resulting in superior durability, chemical resistance, penetration resistance, and corrosion resistance.

[0032] One embodiment of the present invention is a baking powder coating composition containing polyethylene resin, comprising one or more hydrophobic porous coordination polymers (PCPs) / metal-organic structures (MOFs) and one or more hydrophilic porous coordination polymers (PCPs) / metal-organic structures (MOFs).

[0033] Porous coordination polymers (PCPs) / metal-organic frameworks (MOFs) can adsorb different substances depending on their properties. By including both hydrophobic and hydrophilic porous coordination polymers (PCPs) / metal-organic frameworks (MOFs), the variety of substances that can be adsorbed increases, resulting in superior durability, chemical resistance, penetration resistance, and corrosion resistance.

[0034] The amount of polyethylene resin blended is preferably 75.00% to 99.99% by weight of the entire powder coating composition for baking.

[0035] By blending polyethylene resin at a concentration of 75.00% to 99.99% by weight, it is possible to provide a powder coating composition for baking that has high adhesion, contains a sufficient amount of porous coordination polymer (PCP) / metal-organic structure (MOF), and forms a lining film with excellent durability, chemical resistance, penetration resistance, and corrosion resistance.

[0036] Preferably, the polyethylene resin is an ultra-high molecular weight polyethylene with a molecular weight exceeding 1,000,000.

[0037] According to this configuration, a powder coating composition for baking can be obtained that provides a lining film with excellent durability.

[0038] Ultra-high molecular weight polyethylene (UHMW-PE) is a synthetic resin classified as a thermoplastic resin, referring to polyethylene resin with a molecular weight of 1 million to 7 million, compared to the usual 200,000 to 300,000. A major characteristic of ultra-high molecular weight polyethylene is its excellent abrasion resistance and lubricity. Due to its stable molecular structure, it has excellent chemical resistance and can be used in environments where chemical solutions are used. Its low water absorption rate of 0.01% makes it an ideal material for coatings in areas where water is used.

[0039] The mixture may further contain one or more additives selected from the group consisting of silicon carbide, carbon nanotubes, and graphene, which have high chemical resistance and ensure electrical conductivity.

[0040] The material may further contain phenolic, phosphite, thioether, or blended antioxidants that improve the heat resistance of polyethylene during processing and use.

[0041] According to this configuration, a lining film with excellent durability can be obtained.

[0042] One embodiment of the present invention is a liquid coating composition for baking, wherein the above-described powder coating composition for baking is dispersed in a solvent.

[0043] According to this configuration, since the powder coating composition for baking is dispersed in the solvent, it becomes possible to coat substrates that are difficult to coat with powder coating compositions.

[0044] One embodiment of the present invention is a coating comprising a powder coating composition for baking or a liquid coating composition for baking that contains a polyethylene resin as described above.

[0045] According to this configuration, a lining film with excellent durability, chemical resistance, penetration resistance, and corrosion resistance can be obtained because it contains the polyethylene resin described above.

[0046] In one embodiment of the present invention, the coating has a film thickness of 40 μm to 5000 μm.

[0047] If the coating thickness is insufficient, durability, chemical resistance, penetration resistance, and corrosion resistance cannot be obtained. If the coating thickness is excessive, there is a risk of loss of smoothness due to foaming within the coating, cracks on the coating surface, and unevenness.

[0048] A coating body according to one embodiment of the present invention is a coating body having a substrate, a primer layer formed on the surface of the substrate, and one or more polyethylene resin coating layers formed on the primer layer, wherein the polyethylene resin coating layer is a coating as described above.

[0049] According to this configuration, a coating with excellent durability, chemical resistance, penetration resistance, and corrosion resistance can be obtained because it contains the polyethylene resin described above.

[0050] The present invention provides a powder coating composition and a liquid coating composition for baking containing polyethylene resin, and a coating and film body containing this powder coating composition or liquid coating composition for baking, which have excellent durability, chemical resistance, penetration resistance, and corrosion resistance, and form a good lining coating without causing defects such as cracks.

[0051] This is a structural cross-sectional view of a coating according to an embodiment of the present invention. The X-ray diffraction pattern of AP5015 is shown. The thermogravimetric differential thermal analysis (TG-DTA) measurement results of AP5015 are shown. The thermogravimetric differential thermal analysis (TG-DTA) measurement results of PM200 are shown. A schematic diagram of a corrosion resistance test method for a coating according to an embodiment of the present invention is shown. Test example 1 after immersion in 5% hydrochloric acid for two weeks under a temperature of 80°C is shown. Test example 1 after immersion in 5% hydrochloric acid for three weeks under a temperature of 80°C is shown. Test example 2 after immersion in 5% hydrochloric acid for two weeks under a temperature of 80°C is shown. Test example 3 after immersion in 5% hydrochloric acid for two weeks under a temperature of 80°C is shown. Test example 3 after immersion in 5% hydrochloric acid for three weeks under a temperature of 80°C is shown. Test Example 4 after immersion in 5% hydrochloric acid for 2 weeks at a temperature of 80°C is shown. Test Example 4 after immersion in 5% hydrochloric acid for 3 weeks at a temperature of 80°C is shown. Test Example 5 after immersion in 5% hydrochloric acid for 2 weeks at a temperature of 80°C is shown. Test Example 5 after immersion in 5% hydrochloric acid for 3 weeks at a temperature of 80°C is shown. Test Example 6 after immersion in 5% hydrochloric acid for 2 weeks at a temperature of 80°C is shown. Test Example 6 after immersion in 5% hydrochloric acid for 3 weeks at a temperature of 80°C is shown. Test Example 6 after immersion in 5% hydrochloric acid for 4 weeks at a temperature of 80°C is shown. Test Example 6 after immersion in 5% hydrochloric acid for 4 weeks at a temperature of 80°C is shown, followed by adhesion measurement. Comparative Example 1 after immersion in 5% hydrochloric acid for 2 weeks at a temperature of 80°C is shown. Comparative Example 1 after immersion in 5% hydrochloric acid for 3 weeks at a temperature of 80°C is shown. The following shows the fluoropolymer lining coating NF-020GLP after being immersed in 5% hydrochloric acid at a temperature of 80°C for two weeks. The following shows the fluoropolymer lining coating NF-020GLP after being immersed in 5% hydrochloric acid at a temperature of 80°C for three weeks. The following shows the fluoropolymer lining coating NF-020GLP after being immersed in 5% hydrochloric acid at a temperature of 80°C for four weeks. The following shows the fluoropolymer lining coating NF-020GLP after being immersed in 5% hydrochloric acid at a temperature of 80°C for four weeks and then subjected to adhesion testing. The following shows the results of the steam resistance test before testing, after one exposure, and after two exposures. The following shows the results of the steam resistance test after three to five exposures.

[0052] Porous coordination polymers (PCPs) are materials based on complex chemistry that have a porous structure formed by coordination bonds between a central metal and organic ligands. In PCPs, the central metal and organic ligands are continuously coordinated, resulting in a crystalline, three-dimensional polymer structure with internal spaces (pores).

[0053] Furthermore, porous coordination polymers (PCPs) are also called metal-organic frameworks (MOFs). These compounds have several alternative names, such as porous metal complexes, but in this specification, they will be consistently referred to as "porous coordination polymers (PCPs) / metal-organic frameworks (MOFs)." Therefore, the present invention should not be understood as not intending to include these compounds, which are referred to by alternative names such as porous metal complexes.

[0054] In this specification, when the term "paint composition" is used, it refers to the powder coating composition for baking containing polyethylene resin and the liquid coating composition for baking according to the present invention.

[0055] In this specification, "coating" refers to a single-layer or multi-layer polyethylene resin lining coating that includes at least one coating layer coated with the paint composition of the present invention. That is, "coating" in this specification includes a multi-layer polyethylene resin lining coating having at least one coating layer coated with the paint composition of the present invention and a coating layer coated with a general paint composition.

[0056] In this specification, "coating" means a structure in which a substrate, a primer layer on the substrate, and a coating on the primer layer are arranged in layers.

[0057] Furthermore, the effects and characteristics of the coating of the present invention are understood to be the same as those of the coating body of the present invention.

[0058] The following describes embodiments of the paint composition, its coating, and the coating body according to the present invention.

[0059] <Paint Composition> The paint composition comprising polyethylene resin according to this embodiment is a paint composition comprising polyethylene resin in which porous coordination polymers (PCP) / metal-organic structures (MOFs), which are formed by coordination bonding between organic ligands and a central metal, are dispersed. Here, the paint composition comprises one or more porous coordination polymers (PCP) / metal-organic structures (MOFs).

[0060] Porous coordination polymers (PCPs) / metal-organic frameworks (MOFs) have a polymer structure with a pore structure, which is thought to prevent or delay the penetration of components that reduce the durability of the coating, thus enabling the creation of a coating with excellent durability.

[0061] The components that cause a decrease in the durability of the coating are liquids and / or gases. In other words, paint compositions can be given the property of adsorbing liquids and / or gases by porous coordination polymers (PCPs) / metal-organic structures (MOFs).

[0062] The gases that can be adsorbed are not limited to, but include water vapor, hydrogen sulfide, sulfurous acid, nitrite, chlorine, hydrogen bromide, hydrogen chloride, organic acids such as acetic acid and acrylic acid, amines, and alkaline gases such as ammonia.

[0063] Polyethylene resin is permeable to gases, which can cause the substrate of the coating to react with gases and corrode. Porous coordination polymers (PCPs) / metal-organic frameworks (MOFs) adsorb gases, thus reducing the gas permeability of the coating and suppressing a decrease in coating adhesion and corrosion of the substrate.

[0064] To uniformly disperse the porous coordination polymer (PCP) / metal-organic structure (MOF) in polyethylene resin, the porous coordination polymer (PCP) / metal-organic structure (MOF) is in powder form. To obtain this form, it is preferable to mix the polyethylene resin and the porous coordination polymer (PCP) / metal-organic structure (MOF) using a ball mill or the like.

[0065] The amount of porous coordination polymer (PCP) / metal-organic structure (MOF) in the coating composition according to this embodiment is 0.01% to 20.00% by weight of the total coating composition. More preferably, the amount of porous coordination polymer (PCP) / metal-organic structure (MOF) is 0.1% or more by weight of the total coating composition. Even more preferably, the amount of porous coordination polymer (PCP) / metal-organic structure (MOF) is 15.00% or less by weight of the total coating composition. If the amount of porous coordination polymer (PCP) / metal-organic structure (MOF) is insufficient, the desired sufficient durability, chemical resistance, corrosion resistance, etc. cannot be obtained. If the amount is excessive, it will not form a proper film on the substrate.

[0066] The porous coordination polymer (PCP) / metal-organic structure (MOF) incorporated into the coating composition according to this embodiment has a 5% decomposition temperature from 100°C in air, as measured by calorimetrymally-suggested thermal analysis (TG-DTA), which is higher than the melting point of the main component, polyethylene resin.

[0067] Because the porous coordination polymer (PCP) / metal-organic structure (MOF) possesses this property, when the paint composition is fired to form a film, the porous coordination polymer (PCP) / metal-organic structure (MOF) does not decompose, and the film can have excellent durability, chemical resistance, penetration resistance, and corrosion resistance. Furthermore, even under usage conditions where the film is exposed to high temperatures, there is no risk of the film losing its durability, chemical resistance, penetration resistance, and corrosion resistance.

[0068] The central metal of a porous coordination polymer (PCP) / metal-organic structure (MOF) may include metal ions such as Li, Be, Mg, Al, Ca, Sc, Ti, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Mo, Ru, Rh, Pd, Pb, In, W, Re, Pt, or lanthanides. Furthermore, these metal ions may be present individually or in combination of two or more types.

[0069] As a result, the structure of the porous coordination polymer (PCP) / metal-organic structure (MOF) changes depending on the type of metal and / or the valency of the metal ions, and the chemical properties such as durability, chemical resistance, corrosion resistance, and heat resistance also change. Therefore, it is possible to adjust durability, chemical resistance, corrosion resistance, and heat resistance according to the application.

[0070] Furthermore, from the perspective of obtaining superior durability, chemical resistance, corrosion resistance, and heat resistance, Al ３＋ Co ３＋ Co ２＋ Ni ２＋ Ni ＋ ,Cd ２＋ ,Cd ＋ , Zn ２＋ Fe ３＋ Fe ２＋ Ti ３＋ , and Zr ４＋ It is preferable that the metal ion contains one or more metal ions selected from the group consisting of the following:

[0071] At least one of the central metals supports one or more anions, and the central metal may exist in the porous coordination polymer (PCP) / metal-organic structure (MOF) in coordination with the organic ligand.

[0072] For example, when using a carboxylic acid as a ligand, deprotonation occurs to produce -CO ２ － Because it coordinates to the metal in this form, the entire structure becomes neutral with only the metal ion of the central metal and the ligand, and pores are formed inside. On the other hand, ligands that coordinate to the metal cation in a neutral state, such as 4,4'-bipyridyl, maintain electrical neutrality after the formation of the porous coordination polymer (PCP) / metal-organic structure (MOF). As a result, the framework of the porous coordination polymer (PCP) / metal-organic structure (MOF) becomes positively charged, and anions enter the interior to compensate for this.

[0073] Anion is F － , Cl － , Br － , I － H － , O ２－ , O ２ ２－ S ２－ , N ３－ , CN － , OH － , HCO ３ － , CH ３ COO － , H(COO) ２ － , (COO) ２ ２－ , CO ３ ２－ , HS － , HSO ４ － , SO ４ ２－ , SO ３ ２－ , S ２ O ３ ２－ , SCN － , NCS － , NO ３ － , NO ２ － , ONO － , ClO － , ClO ２ － , ClO ３ － , ClO ４ － , H ２ PO ４ － , HPO ４ ２－ may contain anions such as these. These anions may contain only one kind or may contain two or more kinds.

[0074] From the viewpoint of obtaining more excellent durability, chemical resistance, corrosion resistance, and heat resistance, the anion preferably contains one or more anions selected from the group consisting of OH － , CO ３ ２－ and, O ２－ .

[0075] Further, it is preferable that at least one of the central metals forms an oxo structure together with the anion. A coating composition can be obtained in which the oxo structure interacts with the chemical and provides a coating film having more excellent corrosion resistance and chemical resistance.

[0076] The organic ligands are 1,3-benzenedicarboxylic acid, 1,4-benzenedicarboxylic acid, 1,3,5-benzenetricarboxylic acid, 4,4'-bipyridyl, imidazole, 1,3,5-tris(4-carboxyphenyl)benzene, fumaric acid, maleic acid, 5-cyano-1,3-benzenedicarboxylic acid, 9,10-anthracenedicarboxylic acid, 2,2'-diamino-4,4'-stilbendicarboxylic acid, 2,5-diaminoterephthalic acid, 2,2'-dinitro-4,4'-stilbendicarboxylic acid, 2,5-dihydroxyterephthalic acid, 3,3',5,5'-tetracarboxydiphenylmethane, 1,2,4,5-tetrakis(4-carboxyphenyl)benzene, terephthalic acid, 4,4',4'-s-triazine-2,4,6-triyl-tribenzoic acid, and 1,3,5-tris(4'-cal It may contain organic ligands such as boxy[1,1'-biphenyl]-4-yl)benzene, trimesic acid, 2,6-naphthalenedicarboxylic acid, 2-hydroxyterephthalic acid, biphenyl-3,3',5,5'-tetracarboxylic acid, biphenyl-3,4',5-tricarboxylic acid, 5-bromoisophthalic acid, malonic acid, 2-methylimidazole, 5-cyano-1,3-benzenedicarboxylic acid, 2-aminoterephthalic acid, 1,2-di(4-pyridyl)ethylene, 4,4'-ethylenedipyridine, 2,3-pyrazinedicarboxylic acid, 1,4-diazabicyclo[2.2.2]octane, 3,5-pyridinedicarboxylic acid, trans,trans-muconic acid, 5-nitroisophthalic acid, 5-methylisophthalic acid, 2-hydroxyterephthalic acid, 4,4'-biphenyldicarboxylic acid, and trimesic acid. Furthermore, these organic ligands may be present in a single form or in a multiplicity of two or more forms.

[0077] Furthermore, from the viewpoint of obtaining superior durability, chemical resistance, corrosion resistance, and heat resistance, it is preferable to include one or more organic ligands selected from the group consisting of 1,3-benzenedicarboxylic acid, 1,4-benzenedicarboxylic acid, 1,3,5-benzenetricarboxylic acid, 4,4'-bipyridyl, imidazole, 1,3,5-tris(4-carboxyphenyl)benzene, fumaric acid, terephthalic acid, and maleic acid as organic ligands.

[0078] The porous coordination polymer (PCP) / metal-organic framework (MOF) preferably has a pore opening area of 0.15 nm ２ to 7.00 nm ２ It is preferable that it is.

[0079] When the pore opening area of the pores is smaller than 0.15 nm ２ , adsorption of gas molecules with a large molecular weight becomes impossible. When the pore opening area of the pores is larger than 7.00 nm ２ , the effect due to capillary condensation attenuates, and the property of adsorbing gas deteriorates.

[0080] The porous coordination polymer (PCP) / metal-organic framework (MOF) preferably has a specific surface area (BET specific surface area) larger than 900.00 m ２ / g.

[0081] When the specific surface area (BET specific surface area) is larger than 900.00 m ２ / g, the gas adsorption amount increases, and more excellent durability, chemical resistance, impermeability, and corrosion resistance can be obtained.

[0082] The porous coordination polymer (PCP) / metal-organic framework (MOF) has properties derived from the constituent central metal and organic ligand. For example, thermal conductivity and dielectric properties change depending on the central metal. Hydrophobicity / hydrophilicity etc. change depending on the organic ligand. Therefore, the central metal and organic ligand can be selected according to the environmental conditions to which the coating or coated body is applied.

[0083] The coating composition may contain a plurality of types of porous coordination polymers (PCP) / metal-organic frameworks (MOF). As described above, the porous coordination polymer (PCP) / metal-organic framework (MOF) has different properties depending on the difference in the central metal and organic ligand. By blending a plurality of types of porous coordination polymers (PCP) / metal-organic frameworks (MOF) with different properties, various properties can be imparted to the coating composition and the coating.

[0084] As an example of a formulation of multiple types of porous coordination polymers (PCPs) / metal-organic structures (MOFs), a paint composition may include one or more hydrophobic porous coordination polymers (PCPs) / metal-organic structures (MOFs) and one or more hydrophilic porous coordination polymers (PCPs) / metal-organic structures (MOFs).

[0085] By including both hydrophobic porous coordination polymers (PCPs) / metal-organic structures (MOFs) and hydrophilic porous coordination polymers (PCPs) / metal-organic structures (MOFs), the variety of substances that can be adsorbed increases, resulting in superior durability, chemical resistance, penetration resistance, and corrosion resistance.

[0086] The polyethylene resin contained in the coating composition according to this embodiment is thermoplastic and insoluble in both polar and non-polar solvents.

[0087] Examples of polar solvents include water, formic acid, acetic acid, methanol, ethanol, propanol, isopropanol, n-butanol, acetone, and ethyl acetate. Examples of nonpolar solvents include benzene, toluene, hexane, diethyl ether, and dichloromethane.

[0088] Since the polyethylene resin targeted by the present invention is insoluble in both polar and non-polar solvents, it is possible to provide a coating composition that can form a film with excellent chemical resistance and solvent resistance.

[0089] The amount of polyethylene resin added to the total paint composition is 70.00% to 99.99% by weight. Preferably, it is 73.00% to 96.00% by weight. More preferably, it is 75.00% to 90.00% by weight.

[0090] If the polyethylene resin content is less than 70.00% by weight, problems such as cracking will occur during film formation. Furthermore, by setting this upper limit for polyethylene resin, a sufficient amount of porous coordination polymer (PCP) / metal-organic structure (MOF) can be included.

[0091] The polyethylene resin is preferably an ultra-high molecular weight polyethylene with a molecular weight exceeding 1,000,000. If the molecular weight is low, there is a concern that durability will decrease due to a reduction in molecular weight caused by the baking process.

[0092] Polyethylene resin is thermoplastic and insoluble in both polar and nonpolar solvents. Therefore, by using powder coatings containing one or more of these fluororesins, a lining film with excellent durability can be obtained.

[0093] The material may further contain one or more additives selected from the group consisting of silicon carbide, carbon nanotubes, and graphene, which have high chemical resistance and ensure electrical conductivity, from the viewpoint of providing antistatic properties, mitigating film shrinkage, improving film strength, and improving abrasion resistance.

[0094] To improve the heat resistance of polyethylene, it may further contain antioxidants such as phenolic, phosphite, thioether, or blends thereof.

[0095] By using powder coatings containing one or more of these additives, a lining film with excellent durability can be obtained.

[0096] The paint composition is a paint composition for forming a film by baking (baking process).

[0097] The coating composition can be provided in the form of a powder coating. The coating composition provided in the form of a powder coating does not contain a solvent. Providing it in the form of a powder coating makes it easy to adjust the film thickness.

[0098] Furthermore, the coating composition is not necessarily limited to the form of a powder coating composition. In some cases, it may be a liquid coating composition for baking in which the powder coating composition is dispersed in a solvent with a surfactant or the like.

[0099] Either a polar or nonpolar solvent may be used. While not limited to specific solvents, water, alcohols (such as methanol, ethanol, propanol, isopropanol, or n-butanol, propylene glycol, etc.), ketones (such as acetone), aromatic compounds (such as benzene or toluene, etc.) can be used.

[0100] In the form of a liquid coating composition, the particle sizes of the polyethylene resin, porous coordination polymer (PCP) / metal-organic frame (MOF), and other additives are smaller compared to the form of a powder coating composition. While not limited to these particle sizes, examples include sizes ranging from approximately 0.01 μm to 50 μm. For the polyethylene resin, a dispersion called a dispersion, in which particles of approximately 0.2 μm are pre-dispersed in a water-based liquid, may also be used.

[0101] <Coating and Coating Body> Next, the method for forming the coating according to this embodiment will be described, as well as the coating body having the coating.

[0102] The lining film according to this embodiment is formed on a substrate via a primer layer using a paint composition containing polyethylene resin as described above.

[0103] Figure 1 is a cross-sectional view of a coated body (10) in which a coating (lining coating) (3) is formed on a substrate (1) via a primer layer (2).

[0104] The substrate (1) is not particularly limited, but if a baking process is performed when forming a primer layer (2) or a coating (3) on the substrate (1), it is preferable to use a metal, quartz glass, ceramics, etc. that can withstand the heat during baking. Among these, quartz glass is preferred because it provides high corrosion resistance.

[0105] Furthermore, the substrate (1) may be pre-treated (blast treatment, plating, etc.) to improve its adhesion to the primer layer (2).

[0106] A primer layer (2) is formed on the substrate (1). By forming a primer layer (2) on the substrate (1), the adhesion between the substrate (1) and the coating (3) can be improved. Specifically, the raw materials for the primer layer (2) are applied to the substrate (1), and the primer layer (2) is formed by drying or baking as needed.

[0107] The primer layer (2) is not particularly limited, but silane coupling agents and elastomers are preferred. Silane coupling agents having amino groups and styrene elastomers having amino groups at their terminal groups are particularly preferred.

[0108] After forming the primer layer (2), a coating (3) is formed on the primer layer (2) using the paint composition of this embodiment.

[0109] The paint composition of this embodiment may be used for the entire layer, or it may be used for some layers and a general paint composition for the other layers. There are no particular restrictions on the ratio of the film thickness made up of the paint composition of this embodiment, but 5% to 100% of the total film thickness is preferable.

[0110] The paint composition of this embodiment or a general paint composition is applied onto a primer layer (2) by electrostatic powder coating or spray coating, and one or more layers of coating (3) are formed by repeating the baking process.

[0111] The thickness of the formed coating (3) is preferably 40 μm to 5000 μm. If the thickness of the coating (3) is insufficient, durability, chemical resistance, penetration resistance, and corrosion resistance cannot be obtained. If the thickness is excessive, there is a risk of loss of smoothness due to foaming within the coating (3), cracks on the coating surface, and unevenness.

[0112] Furthermore, although the mixing of the paint composition varies depending on the mixing conditions, it is preferable to mix it thoroughly using a ball mill or the like to prevent uneven distribution of porous coordination polymers (PCPs) and the retention of clumps. It is preferable to prepare a masterbatch with a high concentration of dispersion and then mix it to an appropriate concentration using a Henschel mixer or the like.

[0113] Furthermore, while examples of baking conditions for the primer layer (2) and the coating (3) include baking at a temperature of 150°C to 200°C for 5 to 120 minutes, the conditions are not limited to these. Baking can be carried out, for example, using an electric furnace.

[0114] Through this process, a coated body (10) can be obtained, which has a base material (1), a primer layer (2) formed on the surface of the base material (1), and a polyethylene resin coating layer consisting of one or more coating layers (3) formed on the primer layer (2).

[0115] The effects of the present invention will be made clearer by providing the following examples for evaluating the paint composition, coating, and coating body according to the present invention.

[0116] However, the present invention is not limited to the embodiments shown in the following examples.

[0117] In the following examples, AP5015 (manufactured by Atomis Co., Ltd.), which has a structure similar to Al(OH)(fumarate), was used as the porous coordination polymer (PCP) / metal-organic frame (MOF). The ligand for AP5015 is fumaric acid.

[0118] Figure 2 shows the X-ray diffraction pattern of AP5015.

[0119] <Example 1> Thermogravimetric differential thermal analysis of porous coordination polymer (PCP) / metal-organic frame (MOF) and polyethylene resin

[0120] Thermogravimetric differential thermal analysis (TG-DTA) was performed on the porous coordination polymer (PCP) / metal-organic frame (MOF) and polyethylene resin used in the examples.

[0121] The porous coordination polymers (PCPs) / metal-organic frameworks (MOFs) and polyethylene resins subjected to thermogravimetric differential thermal analysis (TG-DTA) are as follows:

[0122] ・Porous coordination polymer (PCP) / metal-organic framework (MOF) AP5015 (PCP / MOF manufactured by Atomis Co., Ltd. Al(OH) (fumarate) = Al(OH)(C４ H ２ O ４ The pores are rhomboid in shape, measuring 0.57 nm × 0.60 nm. The pore opening area is 0.17 nm. ２ BET specific surface area: 900-2000m ２ / g)

[0123] • Polyethylene resin PM200 (Ultra-high molecular weight polyethylene powder coating manufactured by Mitsui Chemicals, Inc., molecular weight 1,800,000)

[0124] • Silicon carbide NG H-BD#1000 (Green silicon carbide manufactured by Taiheiyo Alundum) Hereafter referred to as H-BD.

[0125] • Surfactant Pegnol DK-082 (Polyoxyalkylene alkyl ether surfactant manufactured by Toho Chemical Industry Co., Ltd.) Hereinafter referred to as Pegnol.

[0126] - Antioxidant ADEKA STAB AO80 (Phenol-based antioxidant manufactured by ADEKA Corporation. Chemical name: 3,9-bis{2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl]propionyloxy)-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5,5]undecane) (hereinafter referred to as AO80).

[0127] • Silane coupling agent DOWSIL Z-6011 (aminopropyltriethoxysilane manufactured by Dow-Toray Industries, Inc.) (hereinafter referred to as Z-6011)

[0128] Figure 3 shows the thermogravimetric differential thermal analysis (TG-DTA) results for AP5015. Figure 4 shows the thermogravimetric differential thermal analysis (TG-DTA) results for PM200.

[0129] As shown in Figure 3, the 5% decomposition temperature of AP5015 in air from approximately 100°C was 404.34°C.

[0130] Furthermore, as shown in Figure 4, PM200 showed a peak melting temperature at 142.48°C.

[0131] Therefore, the 5% decomposition temperature of AP5015 from 100°C was higher than the melting point of PM200. <Example 2> Formulation of paint composition

[0132] According to Tables 1, 2, and 3, the formulation examples and comparative formulation examples were formulated as liquid paint compositions. Note that AP5015 and PM200 in Tables 1, 2, and 3 are the same porous coordination polymer (PCP) / metal-organic structure (MOF) and polyethylene resin that were subjected to thermogravimetric differential thermal analysis (TG-DTA) in Example 1. Furthermore, PM200 is thermoplastic and insoluble in both polar and non-polar solvents.

[0133] The paint compositions according to the formulation examples were formulated according to Tables 1 and 2.

[0134] (Example Formulation) Formulation Example 1 was prepared according to the proportions shown in Table 1. AP5015 and PM200 from Table 1 were combined, mixed in a ball mill for two days, and passed through a sieve with a 300 μm mesh size to obtain Formulation Example 1.

[0135] Formulas 2 to 7 were obtained by mixing Formula 1 with PM200, H-BD, Pegnol, purified water, and isopropyl alcohol, respectively, according to the proportions in Table 1, and for Formula 7, AO80 was also added and mixed in a stirrer for 10 minutes.

[0136] Table 1(A) shows the amount of porous coordination polymer (PCP) / metal-organic structure (MOF) blended in the powder coating in the paint composition, and (B) shows the amount of polyethylene resin blended in the powder coating.

[0137] (Comparative formulation example) The paint composition according to the comparative formulation example was formulated according to Table 2.

[0138] Comparative formulations 1 to 4 were obtained by mixing the materials according to the proportions shown in Table 2 for 10 minutes in a stirrer that did not contain porous coordination polymers (PCPs) or metal-organic frameworks (MOFs).

[0139] Table 2(A) shows the amount of porous coordination polymer (PCP) / metal-organic structure (MOF) blended in the powder coating in the paint composition, and (B) shows the amount of polyethylene resin blended in the powder coating.

[0140]

[0141]

[0142] <Example 3> Formation of a coating

[0143] To form the coatings of Test Examples 1-6 and Comparative Example 1, a primer layer was first formed on the substrate by blast treatment. Quartz glass (3 mm thick, 160 mm square) was used as the substrate.

[0144] The primer layers for Test Examples 1 to 5 were formed by mixing (a) and (b) below in a weight ratio of 9:1 and baking them at 150°C for 60 minutes. For Test Example 6, a primer layer with a thickness of 50 μm was formed by applying Comparative Formulation Example 3 and repeating the process of baking it at 150-190°C for 60-90 minutes.

[0145] (a) Isopropyl alcohol (b) VPS 7163 (manufactured by Evonik Corporation, silane coupling agent)

[0146] The following provides a more detailed explanation of the coating (lining coating layer) used in the test example.

[0147] Using formulation examples 2-7 and comparative formulation examples 2 and 4, coatings having the coatings of test examples 1-6 were formed on a primer layer, as shown in Table 3 below. Furthermore, using comparative formulation examples 1 and 2, coatings having the coating of comparative example 1 were formed, as shown in Table 4. For test examples 1-6 and comparative example 1, the coatings were all applied by spray coating, with the paint composition according to the formulation example or comparative formulation example being applied and then baked at 150-190°C for 60 minutes, repeating this process until the total film thickness reached 300 μm.

[0148]

[0149] <Example 4> Corrosion Resistance Test

[0150] Corrosion resistance tests were performed on the prepared test examples 1 to 6, comparative example 1, and the fluoropolymer coating NF-020GLP for quartz using a lining tester LA-15 (manufactured by Yamazaki Seiki Kenkyusho Co., Ltd.).

[0151] In the corrosion resistance test, as shown in Figure 5, the lower half of the coatings of Test Examples 1 to 6, Comparative Example 1, and the fluoropolymer coating NF-020GLP for quartz were immersed in a 5% hydrochloric acid solution, and the upper half was exposed to the volatilized 5% hydrochloric acid by sealing the container.

[0152] The test was conducted at a temperature of 80°C using 5% hydrochloric acid for 3 to 4 weeks.

[0153] (Test items) Specifically, the following were evaluated.

[0154] The time until abnormalities such as blistering and cracking occurred was measured. Since the test was stopped every week, the sample was disassembled, and the coating was examined, the occurrence of abnormalities is indicated on a weekly basis. A ○ was used if the value was the same as in Comparative Example 1, a ◎ if it exceeded the value, and a △ if it fell below the value. The nature of the abnormality, such as cracks and blisters, was also described.

[0155] Adhesion after a certain period of time: The adhesion to the substrate after a certain period of time was evaluated using the peel strength test specified in JIS K 5400. As shown in Figure 5, measurements were taken twice, on the left and right sides, with A and B corresponding to the gas phase and C and D corresponding to the liquid phase. In addition, the initial adhesion to the substrate was evaluated by performing the peel strength test on a portion that was not immersed in hydrochloric acid, as shown in E.

[0156] (Test Results) The test results are shown in Table 5. The results of a similar test conducted on our fluoropolymer coating for quartz, NF-020GLP (film thickness 200 μm), are also included.

[0157]

[0158] As shown in Table 5 and Figures 6-18 and 20-24, Test Examples 1-5, which contained AP5015, showed slower occurrence of abnormalities in the corrosion resistance test or no abnormalities occurred after 3 weeks compared to Comparative Example 1, which did not contain porous coordination polymer (PCP) / metal-organic frame (MOF). In addition, better results were obtained compared to the fluoropolymer coating NF-020GLP. In Test Example 6, although blister formation was observed, no crack formation occurred, and better results were obtained in terms of blister area and residual adhesion compared to the fluoropolymer coating NF-020GLP.

[0159] These effects are thought to be due to the fact that the layer containing the porous coordination polymer (PCP) / metal-organic structure (MOF) is located above the primer layer, causing gases such as water vapor and hydrogen chloride to be adsorbed onto the PCP / MOF before reaching the primer layer, thereby contributing to improved corrosion resistance.

[0160] <Example 5> Formation of coating 2

[0161] To form the coatings of Test Examples 1-3 and Comparative Example 1, the substrate was first degreased and a primer layer was formed. SUS304 (2 mm thick, 50 mm x 100 mm) was used as the substrate.

[0162] The primer layer was formed by mixing (a) and (b) below in a weight ratio of 9:1 and baking it at 150°C for 60 minutes.

[0163] (a) Isopropyl alcohol (b) VPS 7163 (manufactured by Evonik Corporation, silane coupling agent)

[0164] The following provides a more detailed explanation of the coating (lining coating layer) used in the test example.

[0165] Using formulation example 4 and comparative formulation example 2, a coating body having the coating of test example 4 was formed on a primer layer as shown in Table 6 below. Similarly, using comparative formulation examples 1 and 2, a coating body having the coating of comparative example 2 was formed as shown in Table 7. For both test example 6 and comparative example 2, the coating bodies were prepared by spray coating, applying the paint composition according to the formulation example or comparative formulation example, and repeating the process of baking at 150°C for 60 minutes until the total film thickness reached 300 μm.

[0166]

[0167] <Example 6> Steam Resistance Test

[0168] Steam resistance tests were performed in an autoclave on the coatings prepared for Test Example 6 and Comparative Example 2.

[0169] For the steam resistance test, Test Example 6 and Comparative Example 2 were placed in an autoclave at a height that prevented them from coming into contact with the water inside, and were exposed to steam.

[0170] The test conditions involved one 60-minute exposure at 80°C, followed by an evaluation. A second 60-minute exposure at 80°C was then performed and evaluated. This process was repeated until all test subjects were detached.

[0171] (Evaluation Criteria) The evaluation criteria included the peeling of the coating after steam exposure. Complete peeling was marked with ×, clear peeling of 1 / 5 or more of the coating area was marked with △, slight peeling at the edges was marked with ○, and no peeling at all was marked with ◎.

[0172] (Evaluation Results) The evaluation results are shown in Table 8.

[0173]

[0174] As shown in Table 8 and Figure 26, Test Example 6, which contains AP5015, showed better results in the steam resistance test, with less peeling occurring compared to Comparative Example 2, which does not contain a porous coordination polymer (PCP) / metal-organic structure (MOF).

[0175] These effects are thought to be due to the fact that the layer containing the porous coordination polymer (PCP) / metal-organic structure (MOF) is located above the primer layer, causing water vapor to be adsorbed onto the porous coordination polymer (PCP) / metal-organic structure (MOF) before it reaches the primer layer, thereby contributing to improved steam resistance.

[0176] Therefore, the coating composition, its film, and its film body according to the present invention can be said to be useful as they form a film without causing defects such as cracks, and exhibit excellent durability, chemical resistance, penetration resistance, and corrosion resistance.

[0177] Furthermore, the coating composition, its film, and its coated body according to the present invention exhibit durability equivalent to or better than that of fluororesin in corrosion resistance tests, and can be said to have sufficient performance as a PFAS-free coating comparable to fluororesin.

[0178] The baking powder coating composition and liquid coating composition containing polyethylene resin according to the present invention, as well as the coatings and coated bodies containing this baking powder coating composition or liquid coating composition, can be suitably used in equipment (for example, chemical plant equipment, semiconductor manufacturing equipment, cooking equipment, etc.) that requires excellent durability, chemical resistance, penetration resistance, and corrosion resistance without causing defects such as cracks, and can be said to have sufficient performance as a PFAS-free coating comparable to fluororesin.

[0179] 1. Substrate 2. Primer layer 3. Coating (lining film) 10. Coating body

Claims

1. A powder coating composition for baking containing a polyethylene resin in which one or more porous coordination polymers (PCPs) / metal-organic structures (MOFs), formed by coordination bonding between organic ligands and a central metal, are dispersed.

2. The powder coating composition for baking according to claim 1, wherein the porous coordination polymer (PCP) / metal-organic structure (MOF) is in powder form, and its 5% decomposition temperature from 200°C in air, as measured by thermogravimetric differential thermal analysis (TG-DTA), is higher than the melting point of the polyethylene resin, and is blended in an amount of 0.01% to 20.00% by weight relative to the entire coating composition.

3. The baking powder coating composition according to claim 1, wherein the polyethylene resin is thermoplastic and is blended in an amount of 70.00% to 99.99% by weight relative to the entire coating composition.

4. The central metal is Al ３＋ , Co ３＋ , Co ２＋ , Ni ２＋ , Ni ＋ , Cu ２＋ , Cu ＋ , Zn ２＋ , Fe ３＋ , Fe ２＋ , Ti ３＋ , and Zr ４＋ and is present as one or more metal ions selected from the group consisting of, and the metal ions are coordinately bonded to the organic ligand and present in the porous coordination polymer (PCP) / metal-organic framework (MOF). The powder coating composition for baking according to claim 1.

5. The powder coating composition for baking according to claim 1, wherein at least one of the central metals supports one or more anions, and the central metal is present in the porous coordination polymer (PCP) / metal-organic structure (MOF) in coordination with the organic ligand.

6. The anion is OH － CO ３ ２－ and, O ２－ The powder coating composition for baking according to claim 5, comprising one or more anions selected from the group consisting of the following.

7. The powder coating composition for baking according to claim 5, wherein at least one of the central metals forms an oxo structure together with the anion.

8. The powder coating composition for baking according to claim 1, wherein the organic ligand comprises one or more organic ligands selected from the group consisting of 1,3-benzenedicarboxylic acid, 1,4-benzenedicarboxylic acid, 1,3,5-benzenetricarboxylic acid, 4,4'-bipyridyl, imidazole, 1,3,5-tris(4-carboxyphenyl)benzene, fumaric acid, terephthalic acid, and maleic acid.

9. The powder coating composition for baking according to claim 1, wherein the porous coordination polymer (PCP) / metal-organic structure (MOF) imparts gas adsorption properties to the composition.

10. The powder coating composition for baking according to claim 9, wherein the gas is a corrosive gas containing at least water vapor and hydrogen chloride.

11. The porous coordination polymer (PCP) / metal-organic structure (MOF) has a pore area of ​​0.15 nm. ２ ~7.00 nm ２ The powder coating composition for baking according to claim 1.

12. The porous coordination polymer (PCP) / metal-organic structure (MOF) is 900.00 m ２ The powder coating composition for baking according to claim 1, having a specific surface area (BET specific surface area) greater than / g.

13. The powder coating composition for baking according to claim 1, comprising one or more hydrophobic porous coordination polymers (PCPs) / metal-organic structures (MOFs) and one or more hydrophilic porous coordination polymers (PCPs) / metal-organic structures (MOFs).

14. The powder coating composition for baking according to claim 1, wherein the amount of polyethylene resin added is 75.00% to 99.95% by weight of the entire coating composition.

15. The powder coating composition for baking according to claim 1, wherein the polyethylene resin is ultra-high molecular weight polyethylene with a molecular weight exceeding 1,000,000.

16. The powder coating composition for baking according to claim 1, further comprising one or more additives selected from the group consisting of silicon carbide, carbon nanotubes, and graphene, which have high chemical resistance and ensure electrical conductivity.

17. The powder coating composition for baking according to claim 1, further comprising one or more additives selected from the group consisting of phenolic, phosphite, thioether, or blended antioxidants, for improving heat resistance.

18. A liquid coating composition for baking, wherein the powder coating composition for baking described in claim 1 is dispersed in a solvent.

19. A coating comprising the powder coating composition for baking according to claim 1 or the liquid coating composition for baking according to claim 18.

20. The coating according to claim 19, having a film thickness of 40 μm to 5000 μm.

21. A coating body comprising a base material, a primer layer formed on the surface of the base material, and one or more polyethylene resin coating layers formed on the primer layer, wherein the polyethylene resin coating layer is the coating described in claim 19.

Images