Composition

Abstract

A particle coating composition, preferably a powder coating composition, is provided. [Solution] A particle coating composition comprising: (i) an epoxy resin; (ii) a curing agent, the curing agent including an imidazoline ring; (iii) a filler; and (iv) a degassing agent, preferably benzoin, wherein the total amount of the epoxy binder system including the epoxy resin and the curing agent is 40 to 99 wt % based on the total weight of the particle coating composition.

Description

[Technical field]

[0001] introduction The present invention relates to a particulate coating composition, particularly a powder coating composition, comprising an epoxy resin, a hardener containing an imidazoline ring, a filler, and a degassing agent. The present invention also relates to a container containing the composition, and a method for making the composition. Furthermore, the present invention relates to a coating comprising the composition, a substrate coated with the composition, and a method for coating a substrate with the composition.

[0002] The coatings of the present invention advantageously have strong resistance to electrolytes, i.e., they retain their electrical insulating properties and their aesthetic appearance after contact with the electrolyte.The present invention therefore also relates to a battery assembly including a battery cell having a coating formed on at least one surface thereof, the coating being formed from a powder coating composition including an epoxy resin, a curing agent including an imidazole, imidazoline or imidazolidine ring, a filler, and a degassing agent. [Background technology]

[0003] background Electric vehicles are a greener form of transportation, especially when it comes to reducing CO 2 It has been one of the fastest growing industries in recent years, driven by increasing demand to reduce emissions. Batteries are at the heart of electric vehicles.

[0004] Electric vehicles typically have a battery assembly that includes many battery cells, each containing an electrolyte. The battery cells may be arranged in different configurations, but are interconnected to provide an overall battery assembly. Conventionally, the assembly includes modules and fixtures to hold the battery cells.

[0005] Blue PET tape has traditionally been used for the insulation of battery cells in electric vehicles. However, the use of PET tape has several drawbacks, for example, being a thermoplastic film, it softens at relatively high temperatures, making dimensional stabilization at relatively high temperatures problematic. Also, when temperatures exceed about 110 °C, PET melts, increasing the risk of the battery catching fire. This is of particular concern to battery manufacturers, as battery cells made with PET film will spread fire quickly. Finally, adhesion loss occurs in the PET film when sudden temperature changes occur, which can potentially short the battery.

[0006] At the same time, there is an increasing demand for the energy density of batteries used in the vehicle industry. As a result, there is a trend to remove the modules and fixtures present in the battery assembly to provide more space for the battery cells. This technology is called "Cell to Pack (CTP)" technology. Since there are no fixtures in a CTP battery assembly or pack, the battery cells in the pack must be bonded together with a structural adhesive to form a block. The bonded cells need to withstand vibrations during the service life of the electric vehicle. Therefore, the bond strength between the battery cells is important. PET tape has a low bond strength of about 5 MPa to the aluminum substrate of the battery and cannot meet the high demands of the new technology.

[0007] Powder coatings that are free of volatile organic compounds (VOCs) and have excellent adhesion to both the aluminum substrate of the battery cell and to the structural adhesives used in CTP battery assemblies are receiving increasing attention as possible replacements for traditional PET tapes. One of the main challenges to overcome in order to turn this concept into a practical reality is to provide a coating that is electrolyte resistant, i.e., a coating whose performance is not adversely affected by contact with the electrolyte.

[0008] The lowest powder coating curing temperature is 120-130°C. However, the electrolyte present in the battery cell will be damaged if the electrolyte is exposed to these temperatures. Therefore, the battery cell must first be coated with the powder coating and then filled with the electrolyte. Unfortunately, spillage during electrolyte filling is inevitable, as well as some evaporation of the electrolyte. The powder coating must maintain its designed electrical insulation properties and other properties after contacting the electrolyte.

[0009] This is a challenge because the chemicals present in the electrolyte are highly corrosive. For example, lithium batteries contain solvents, additives, and lithium salts, mainly lithium hexafluorophosphate (LiPF6) and other lithium-based salts. If the electrolyte is spilled during filling, the coating on the battery cell comes into contact with hydrofluoric acid produced by the reaction of LiPF6 with water in the air, which is harmful. If a large spill occurs, the coating is destroyed very quickly, and even if a small spill occurs, it is irreversibly damaged, for example losing its insulating properties. Other chemicals present in the electrolyte, such as solvents, will similarly adversely affect important properties of the coating if contact occurs. For example, contact with the electrolyte often causes the coating to discolor, lose its insulating effect, and / or lose adhesion to the substrate.

[0010] Other types of batteries may contain different salts, for example based on nickel, cobalt, and manganese salts, but they all tend to contain similar solvents. The main components of the solvents are ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), carboxylic acid esters, and fluoroethers. Coatings suitable for use on battery cells must be able to withstand contact with these solvents and the corrosive compounds that form in the event of a spill. Summary of the Invention [Problem to be solved by the invention]

[0011] The coatings of the present invention are advantageously highly resistant to electrolytes, i.e., they retain their electrical insulating properties as well as their aesthetic appearance after contact with the electrolyte. Accordingly, the present invention also relates to a battery assembly including a battery cell having a coating formed on at least one surface thereof. [Means for solving the problem]

[0012] Viewed from a first aspect, the present invention provides a particle coating composition, preferably a powder coating composition, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazoline ring; (iii) a filler; and (iv) a degassing agent, preferably benzoin Here, the total amount of the epoxy binder system (which system includes the epoxy resin and the hardener) is 40 to 99 wt %, based on the total weight of the particle coating composition. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Viewed from a further aspect, the present invention provides a container containing a particle coating composition, preferably a powder coating composition, as described above.

[0014] Viewed from a further aspect, the present invention provides a process for preparing a particle coating composition, preferably a powder coating composition, as defined above, comprising: (i) mixing an epoxy resin, a hardener containing an imidazoline ring, a filler, and a degassing agent to form a mixture; and (ii) extruding the mixture to form particles. Includes.

[0015] Viewed from a further aspect, the present invention provides the use of a particulate coating composition, preferably a powder coating composition as described above, for coating a substrate, preferably a metal substrate, such as aluminium.

[0016] Viewed from a further aspect, the present invention provides a method for coating a substrate, preferably a metal substrate, such as aluminium, with a particulate coating composition, preferably a powder coating composition as described above, comprising: i) applying a particle coating composition to a substrate; and ii) curing the particle coating composition Includes.

[0017] Viewed from a further aspect, the present invention provides a coating, preferably a cured coating, comprising the particulate coating composition, preferably a powder coating composition, as described above.

[0018] Viewed from a further aspect, the present invention provides a substrate, preferably a metal substrate, such as aluminium, coated with the above-mentioned particulate coating composition, preferably a powder coating composition, or with a coating as defined above.

[0019] Viewed from a further aspect, the present invention provides a battery assembly including at least one battery cell having a coating formed on at least one surface thereof, the coating comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; formed from a composition comprising Preferably, the total amount of the epoxy binder system (the system including the epoxy resin and the hardener) is 40 to 99 weight percent, based on the total weight of the particle coating composition.

[0020] Preferably the composition is as described above.

[0021] Viewed from a further aspect, the present invention provides the use of a particle coating composition for forming an electrolyte-resistant coating on at least one surface of a substrate, preferably a battery cell, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Here, the total amount of the epoxy binder system including the epoxy resin and the curing agent is preferably 40 to 99% by weight based on the total weight of the particle coating composition.

[0022] Viewed from a further aspect, the present invention provides the use of a particle coating composition for protecting a substrate, in particular a battery cell, against an electrolyte, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0023] Viewed from a further aspect, the present invention provides the use of a particulate coating composition for coating at least one aluminium surface of a battery cell, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0024] Viewed from a further aspect, the present invention provides the use of a particle coating composition for forming at least a base layer on a battery cell, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0025] Viewed from a further aspect, the present invention provides the use of a particulate coating composition for coating a battery cell comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Here, the total amount of the epoxy binder system including the epoxy resin and the curing agent is preferably 40 to 99% by weight based on the total weight of the particle coating composition.

[0026] Viewed from a further aspect, the present invention provides a method for protecting a surface from electrolyte damage, the method comprising: (a) applying a particle coating composition onto a surface; and (b) curing the coating composition to obtain a coating; Including, The particle coating composition comprises: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Including, Preferably, the total amount of the epoxy binder system (said system including the epoxy resin and the hardener) is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0027] Viewed from a further aspect, the present invention provides a method for maintaining electrical insulation of a coating on a substrate following exposure of said coating to (e.g., contact with) an electrolyte, the method comprising: (a) applying a particle coating composition onto a surface; and (b) curing the coating composition to obtain a coating; Including, The particle coating composition comprises: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin Including, Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0028] definition As used herein, the term "particulate coating composition" refers to a mixture of particles that when applied to a surface and heated, e.g., cured, forms a coating thereon.

[0029] As used herein, the term "powder coating composition" refers to a dry, free-flowing powder that when applied to a surface and heated, e.g., cured, forms a coating thereon.

[0030] Generally, the particles constituting the powder have an average diameter of 10 to 120 μm.

[0031] As used herein, the term "epoxy" refers to a three atom cyclic ether.

[0032] As used herein, the term "epoxy-based" refers to polymers or oligomers that contain epoxy groups and / or modified epoxy groups. The term epoxy-based binder encompasses binders that have a conventional epoxy backbone, but in which the epoxy end groups are modified, for example, with acrylic or methacrylic functional groups that can be cured with the same curing agents as the epoxy groups. Epoxy binders contain at least some epoxy groups. The term epoxy is used interchangeably with epoxide.

[0033] As used herein, the term "solid epoxy resin" refers to an epoxy polymer that is solid at ambient temperature and pressure (25° C. and 1 atm). Thus, the term "solid" refers to the physical state of the epoxy-based binder.

[0034] As used herein, the phrase "epoxy equivalent weight" or "EEW" refers to the number of grams of epoxy resin required to provide one mole of epoxy groups. It is measured by ASTM D-1652.

[0035] As used herein, the term "molecular weight" refers to the weight average molecular weight (Mw), unless otherwise specified.

[0036] As used herein, the term "hardener" refers to a compound that, when mixed with an epoxy resin, produces a cured or hardened coating by creating crosslinks within the polymer. Hardeners are sometimes also called hardeners.

[0037] As used herein, the terms "cure accelerator" and "accelerator" are used synonymously and refer to compounds that increase the rate of the curing reaction to harden or harden a coating.

[0038] As used herein, the term "filler" refers to solid particles. Typically, fillers are incorporated into particle coating compositions to increase their volume. Fillers are sometimes also called "extenders."

[0039] As used herein, the term "spherical" when used with respect to particles includes substantially spherical and spherical particles. Substantially spherical particles are equivalent in size to ±1.2 μm, more preferably ±0.6 μm in each of the x, y, and z dimensions.

[0040] As used herein, the term "average diameter" refers to the Z-average diameter size determined by ISO 22412:2017 using a Malvern Mastersizer 2000.

[0041] As used herein, the term D 90 refers to the size at which 90% of the particles have a diameter smaller than the indicated value.

[0042] As used herein, the term D 50 refers to the size at which 50% of the particles have a diameter smaller than the indicated value.

[0043] As used herein, the term D 10 refers to the size at which 10% of the particles have a diameter smaller than the indicated value.

[0044] As used herein, the term "degassing agent" refers to a compound added to a composition to remove gases, such as air, and / or promote the dissolution of gases to avoid the formation of pinholes and bubbles in the formed coating.

[0045] As used herein, the term "leveling agent" refers to a compound added to a particle coating composition to promote powder flow during the melting stage, for example, by breaking weak bonds between particles in the powder and / or by lubricating movement.

[0046] As used herein, the term "flow additive" or "flow agent" refers to compounds added to particle coating compositions to reduce surface tension, reduce surface defects such as craters, pinholes and fish eyes, and increase surface smoothness.

[0047] As used herein, the term "color pigment" refers to a pigment that is added to a composition to impart color. Color pigments include TiO 2 Examples of white pigments include:

[0048] As used herein, the term "rheology modifier" refers to a compound that improves the uniformity of consistency and application characteristics of a coating composition.

[0049] As used herein, the term "weight percent (wt%)" when used in reference to a coating composition refers to the weight of an individual component of the composition relative to the total weight of the composition. The total weight percent of any given coating composition is 100 wt%.

[0050] Detailed Description of the Invention The present invention relates to a particle coating composition, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin Contains Here, the total amount of the epoxy binder system including the epoxy resin and the curing agent is 40 to 99 wt % based on the total weight of the particle coating composition.

[0051] Preferably, the particle coating composition is a powder coating composition.

[0052] Optionally, the coating composition of the present invention further comprises (v) a flow additive, (vi) a color pigment, (vii) a leveling agent, and / or (viii) an additive.

[0053] The particle coating composition of the present invention advantageously produces coatings that are more resistant to contact with electrolytes, such as those present in lithium batteries, than other particle coatings. More specifically, the coating composition of the present invention produces coatings that maintain their insulating and voltage-withstanding properties, even after immersion in an electrolyte (i.e., extreme conditions). The coating composition of the present invention also produces coatings that are less likely to discolor upon contact with an electrolyte than other powder coatings, meaning that they retain a good aesthetic appearance for a longer period of time. Coatings produced by the coating composition of the present invention achieve improved resistance to damage from electrolyte contact while maintaining adequate adhesion to metal, e.g., aluminum, substrates.

[0054] Epoxy Resin The particle coating composition of the present invention comprises an epoxy resin, which is preferably a solid epoxy resin.

[0055] Preferred epoxy resins present in the coating composition of the present invention have an epoxy equivalent weight (EEW) of from 200 to 1950 g / eq, more preferably from 200 to 1300 g / eq, even more preferably from 400 to 1300 g / eq.

[0056] There are two major categories of epoxy resins: glycidyl epoxy resins and non-glycidyl epoxy resins. Some classes of glycidyl epoxy resins include glycidyl-ether epoxy resins, glycidyl-ester epoxy resins and glycidyl-amine epoxy resins. Some classes of non-glycidyl epoxy resins include aliphatic epoxy resins and cycloaliphatic epoxy resins.

[0057] Preferably, the solid epoxy resin present in the particle coating composition of the present invention comprises a glycidyl epoxy resin, more preferably a glycidyl ether epoxy resin. The glycidyl-ether epoxy resin is generally prepared by the condensation reaction of a dihydroxy compound with epichlorohydrin. Preferably, the dihydroxy compound is a bisphenol compound. Therefore, preferably, the epoxy resin is a bisphenol-based epoxy resin.

[0058] Representative examples of solid epoxy resins suitable for use in the compositions of the present invention include bisphenol A-based epoxy resins, bisphenol F-based epoxy resins, novolac-modified bisphenol A-based epoxy resins, isocyanate-modified bisphenol A epoxy resins, cresol novolac-type epoxy resins, O-cresol epoxy resins, silane-modified bisphenol A epoxy resins, rubber-modified bisphenol A epoxy resins, silicone-modified bisphenol A epoxy resins, and mixtures thereof. In preferred particle coating compositions, the solid epoxy resins are selected from bisphenol A-based epoxy resins, bisphenol F-based epoxy resins, novolac-modified bisphenol A-based epoxy resins, isocyanate-modified bisphenol A epoxy resins, cresol novolac-type epoxy resins, O-cresol epoxy resins, and mixtures thereof. In particularly preferred particle coating compositions, the solid epoxy resins are selected from bisphenol A-based epoxy resins, novolac-modified bisphenol A-based epoxy resins, bisphenol F epoxy resins, isocyanate-modified bisphenol A epoxy resins, and mixtures thereof. Bisphenol A-based epoxy resins, novolac-modified bisphenol A-based epoxy resins, and mixtures thereof are particularly preferred. Bisphenol A based epoxy resins are particularly preferred.

[0059] The preferred solid epoxy resins present in the coating composition of the present invention, such as bisphenol A-based epoxy resins, novolac-modified bisphenol A-based epoxy resins, have an epoxy equivalent weight (EEW) of 200 to 1950 g / eq, more preferably 200 to 1300 g / eq, even more preferably 400 to 1300 g / eq, even more preferably 700 to 1300 g / eq, and especially preferably 700 to 1000 g / eq. It is believed that the EEW plays an important role in the performance of the coating. Epoxy resins with a relatively low EEW tend to have lower viscosity and better wetting properties, thereby having better adhesion, but if the EEW is too low, sagging and / or bubbles will occur in the final coating. On the other hand, epoxy resins with a relatively high EEW tend to slow down the degassing of air in the coating as it cures, which is believed to be detrimental to electrolyte resistance. Furthermore, if the EEW of the epoxy resin is too low or too high, the composition will be difficult to process during coating and the final coating produced from the composition will tend to have poor appearance, poor coverage at the edges of the substrate, poor protection at the edges and poor storage stability.

[0060] The particle coating composition of the present invention may include one or more solid epoxy resins. In some preferred particle coating compositions of the present invention, only one type of solid epoxy resin is present, in particular bisphenol A based epoxy resin, novolac modified bisphenol A based epoxy resin or isocyanate modified bisphenol A based epoxy resin. Other preferred coating compositions of the present invention contain a mixture of two or more, for example two solid epoxy resins. A mixture of bisphenol A based epoxy resin and novolac modified bisphenol A based epoxy resin is particularly preferred. When using a mixture of bisphenol A based epoxy resin and novolac modified bisphenol A based epoxy resin, the weight ratio of bisphenol A based epoxy resin to novolac modified bisphenol A based epoxy resin is preferably 10:1 to 1:10, more preferably 5:1 to 1:5, even more preferably 2:1 to 1:2.

[0061] Suitable epoxy resins are commercially available. Representative examples of suitable epoxy resins include KD-213, KD-214C, KD-242K, KD-2200, KD-242G, KD-243G, KD-2103, KD-214M, KD-2203, KD-2104, KD-214L, KD-9002, KD-9003, KD-9004, KD-213C, KD-213H, DER6805, NPCN-704, DER6224, DER6225, DER662E, KD-211G, DER662UH, DER6635, DER6636, DER6637, DER6638, DER6639 ... ER663U, DER663UE, DER664, DER664U, DER664UE, DER672U.DER6510HT, YDCN-500-90P, BE501H, BE502L, BE502, BE503L, BE503, BE504, B E504H, BE505H, BE507, YD-017, BE574P, BFE107, MOE-380, MOE-400, CNE202, CNE220, CNE220H, BE502S, BE503S, NPES-901, NPES-901H, NPES-902, NPES-902H, NPES-903K, NPES-903, NPES-903H, NPES-904, NPES-303, NPES-904H, NPES-304, NPES-907, NPCN-704 and NPER-450.

[0062] The total amount of epoxy resins present in the particle coating composition of the present invention is preferably 38 to 99 wt%, more preferably 38 to 95 wt%, based on the total weight of the particle coating composition. Preferably, the total amount of epoxy resins present in the particle coating composition is 40 to 99 wt% (e.g., 40 to 95 wt%), more preferably 50 to 95 wt%, and even more preferably 60 to 90 wt%, based on the total weight of the particle coating composition.

[0063] Hardener The particle coating composition of the present invention also includes a curing agent, which reacts with the epoxy resin during curing to form a coating, such as a film coating. Thus, the curing agent facilitates providing a coating composition with an acceptable cure time.

[0064] The curing agent present in the particle coating composition of the present invention contains an imidazoline ring. The imidazoline ring may be a 2-imidazoline, a 3-imidazoline or a 4-imidazoline. Preferably, the imidazoline ring is a 2-imidazoline.

[0065] The imidazoline ring present in the curing agent present in the particle coating composition of the present invention can be unsubstituted or substituted.Preferably, the imidazoline ring is substituted.There can be any number of substituents, more preferably there are one or two substituents, and even more preferably there is one substituent.

[0066] When substituted, the imidazoline ring may be substituted at any position.Preferably, the imidazoline ring is substituted at the 2-position, for example, the preferred hardener comprises an imidazoline ring substituted at the 2-position.Optionally, the imidazoline ring present in the hardener present in the particle coating composition of the present invention is a dimer, for example, is linked by an alkylene linker between the two 2-positions of the imidazoline ring.

[0067] Examples of suitable substituents which may be present on the imidazoline ring include aromatic substituents, C 1 ~C 12 Alkyl Substituents, C 1 ~C 6 Alkylene Substituents, Alcohols, Amines, Halides, C 1 ~C 6 Preferred substituents include aromatic substituents (e.g., phenyl or benzyl) and C 1 ~C 12Alkyl substituents (e.g., methyl) are included. More preferred substituents include aromatic substituents (e.g., phenyl or benzyl) and C 2 ~C 12 The imidazoline ring preferably has an aromatic substituent. Examples of suitable aromatic substituents include phenyl and heterocycles such as pyridine, imidazole, furan and thiophene. The preferred aromatic substituent is phenyl, especially unsubstituted phenyl.

[0068] The nitrogen atom of the imidazoline ring may be substituted or unsubstituted. Examples of suitable substituents include C 1 ~C 12 These include alkyl groups, alkyl alcohols and alkyl amines. The nitrogen atom is preferably unsubstituted.

[0069] When phenyl is present as a substituent on the imidazoline ring, it may be unsubstituted or substituted. Examples of suitable substituents include C 1 ~C 6 Alkyl, C 1 ~C 6 These include alkoxy, nitrile, hydroxyl, halide, thiol, and amine. Phenyl substituents may have one or several substituents located at any position on the aromatic ring. Preferably, phenyl present as a substituent is unsubstituted.

[0070] Particularly preferred particle coating compositions of the present invention include a curing agent that contains a 2-imidazoline ring.

[0071] Particularly preferred curing agents present in the coating composition of the present invention comprise (e.g., consist of) a 2-imidazoline ring substituted at the 2-position. Even more preferably, the substituent is aromatic (e.g., phenyl) or C 1 ~C 12 Alkyl substituents (e.g., methyl). Even more preferably, the substituents are aromatic (e.g., phenyl) or C 2 ~C 12It is an alkyl substituent.

[0072] It is particularly preferred that the hardener present in the particle coating composition of the present invention comprises (eg, consists of) 2-phenyl-2-imidazoline (Cas number 936-49-2). [ka]

[0073] More often, imidazolines are used as accelerators. Without wishing to be bound by theory, it is believed that the coating compositions of the present invention use them as hardeners.

[0074] The hardener preferably comprises 2-phenyl-2-imidazoline, for example at >50% by weight of the hardener, more preferably >75% by weight, even more preferably >90% by weight, even more preferably >95% by weight.

[0075] The 2-phenyl-2-imidazoline preferably present in the particle coating composition preferably has a purity of 98% or greater, more preferably 99% or greater.

[0076] Suitable hardeners containing an imidazoline ring are commercially available. For example, 2-phenyl-2-imidazoline for use in the particle coating composition of the present invention is commercially available, for example, from Huangshan Huahui Technology Co. Ltd under the trade name HC31, from Evonik Degussa Coatings & Colour under the trade name Vestagon B31, and from Huangshan Deping Chemical Co. Ltd under the trade name MB 31.

[0077] It will be understood that the hardener and epoxy resin must react to cure the coating. The appropriate amount of hardener and epoxy resin will depend on the relative number of reactive groups, i.e., epoxide in the epoxy resin and amine in the hardener. Generally speaking, the amount of hardener present (wt%) is preferably 1-35 wt%, more preferably 1.5-20 wt%, and even more preferably 2-15 wt%, based on the amount of epoxy resin present on a wt% basis.

[0078] It is preferred that these components are mixed in a ratio such that the hardener is present in a stoichiometric amount of 80-120%, more preferably 90-115%, and even more preferably 100-110%, based on the number of reactive groups in the hardener relative to the number of reactive groups present in the epoxy resin.

[0079] The total amount of the epoxy binder system, including one or more epoxy resins and one or more hardeners, is preferably 40-99 wt.%, more preferably 50-95 wt.%, and even more preferably 60-90 wt.%, based on the total weight of the particle coating composition.

[0080] In the preferred coating compositions of the present invention, the binder system is a pure epoxy resin system, and therefore preferably no other types of resins (e.g. copolymers) are present in the binder system.

[0081] filling material The particle coating composition of the present invention includes a filler. Preferred fillers present in the particle coating composition are inorganic fillers.

[0082] Suitable inorganic filler particles exist in different morphologies, for example, spherical, lamellar, nodular and irregular morphologies.

[0083] The fillers present in the particle coating composition of the present invention preferably have a D of 0.5 to 25 μm, more preferably 1 to 20 μm, even more preferably 1 to 15 μm, and even more preferably 1 to 10 μm. 50 has.

[0084] In the preferred particle coating compositions of the present invention, the filler is selected from barium sulfate, preferably precipitated barium sulfate, mica, talc, wollastonite (calcium metasilicate), glass flake, nepheline, kaolin, dolomite, diatomite, boron nitride, alumina, aluminum hydroxide and mixtures thereof, more preferably barium sulfate, preferably precipitated barium sulfate, kaolin and mixtures thereof. In the particularly preferred particle coating compositions, the filler is selected from precipitated barium sulfate, kaolin, mica and mixtures thereof.

[0085] The particle coating composition of the present invention may comprise a single filler or a combination of two or more fillers.In some preferred particle coating compositions, a single filler is present.When a single filler is present, the filler is preferably selected from precipitated barium sulfate, wollastonite (calcium metasilicate), glass flake, nepheline, kaolin, dolomite, diatomite, boron nitride, alumina, aluminum hydroxide and mixtures thereof.

[0086] In some other preferred particle coating compositions, the combination of two fillers is preferred.Some representative preferred combinations include precipitated barium sulfate and mica, precipitated barium sulfate and talc, precipitated barium sulfate and kaolin, mica and talc, kaolin and talc, and kaolin and mica.The particularly preferred combinations of fillers are precipitated barium sulfate and kaolin, kaolin and talc, and kaolin and mica.

[0087] Suitable fillers are commercially available. Representative examples of suitable fillers include Blanc Fine GM-80 from Gemme Speciality Chemicals Co. Ltd, Blanc Fixe L from Yillong Chemical Group Limited, GL-2500 from Jiangsu Qunxin powder technology Ltd, Specswhite and Micro Mica W1 from Imerys Minerals Ltd, JLH-60D and H6 from Shenzhen JinHaoHui Industrial Department Co.Ltd, and GA-1 from Chuzhou Gera Minerals Co.Ltd.

[0088] The total amount of filler present in the particle coating composition of the present invention is preferably 0.01 to 60 wt %, more preferably 1.5 to 50 wt %, and even more preferably 10 to 38 wt %, based on the total weight of the particle coating composition.

[0089] Degassing agent The particle coating composition of the present invention includes a degassing agent. Conventional commercially available degassing agents can be used.

[0090] Representative examples of suitable degassing agents include cyclohexanedimethanol bisbenzoate, benzoin, benzoin derivatives and mixtures thereof. Preferably, the degassing agent is benzoin or a benzoin derivative, and particularly preferably benzoin. Suitable degassing agents are available from a wide range of commercial suppliers, for example, benzoin is available from Miwon Speciality Chemical Co Ltd under the trade name Miwon benzoin, and benzoin is available from Orgamine Chemicals PVT Ltd, and Ningbo South Sea Chemical Co. Ltd.

[0091] Preferred coating compositions of the present invention comprise from 0.15 to 0.45 wt. %, more preferably from 0.17 to 0.4 wt. %, and even more preferably from 0.2 to 0.35 wt. % of the degassing agent, based on the total weight of the particle coating composition.

[0092] Flow Additives The particle coating composition of the present invention preferably comprises a flow additive.The presence of the flow additive tends to increase surface smoothness, for example by reducing or eliminating surface defects such as craters, fish eyes and pinholes.This is achieved by improving the melt flow properties of the particle coating composition.

[0093] Conventional commercially available flow additives can be used, such as PCL-100 from Kscnt Co. Ltd, Rheoflow PLP 100H(A) from KS Chemical Co. Ltd, Resiflow PV 88 from Worlee-Chemie GmbH.

[0094] Representative examples of suitable flow additives include acrylics, silicon-containing compounds, and fluoropolymers.A preferred particle coating composition of the present invention includes a flow additive that is an acrylic.

[0095] Preferred coating compositions of the present invention comprise from 0.01 to 5 wt. %, more preferably from 0.1 to 3 wt. %, and even more preferably from 0.5 to 1.5 wt. % of a flow additive, based on the total weight of the particle coating composition.

[0096] Color Pigments The particle coating composition of the present invention preferably comprises at least one color pigment. The color pigment may be an inorganic or organic color pigment. Organic color pigments are preferred.

[0097] Representative examples of inorganic color pigments suitable for inclusion in the particle coating compositions of the present invention include titanium dioxide, iron oxide red, black pigments, yellow pigments, chrome pigments, carbon black, and combinations thereof.

[0098] Representative examples of organic pigments suitable for inclusion in the particle coating compositions of the present invention include phthalocyanine, azo, dioxazine, perylene, anthraquinone, thioindigo, isodibenzanthrone, triphenedioxane, quinacridone pigments, vat dye pigments, and combinations thereof.

[0099] Preferred color pigments for inclusion in the particle coating compositions of the present invention are selected from titanium dioxide, carbon black, organic red pigments, organic yellow pigments, organic blue pigments, ultramarine blue, and organic green pigments.

[0100] Other preferred particle coating compositions of the present invention contain less than 5% by weight, more preferably less than 2% by weight, and even more preferably less than 1.1% by weight of carbon black. Without wishing to be bound by theory, it has been found that when higher levels of carbon black are present, the electrolyte resistance of the resulting coating is compromised. This is believed to be due to the conductive properties of carbon black.

[0101] Suitable colour pigments are commercially available, for example, NTR-606, Beablack 2669F, Beablack 2870F, Red 122, DPP Red SR2P, Yellow 139, Sudafast blue 2789, Blue 51, Green 2730K.

[0102] Generally speaking, color pigments should be included in the particle coating composition in the minimum amount necessary to provide the desired color. The amount of color pigment required depends in part on the type of color pigment. As an example, titanium dioxide may be present at 25% by weight, while carbon black may be present in an amount up to 1.1% by weight. Those skilled in the art can determine the appropriate amount for different types of pigments.

[0103] If present, the amount of color pigment present in the particle coating composition of the present invention is preferably from 0.0005 to 30% by weight, more preferably from 0.001 to 25% by weight, and even more preferably from 0.01 to 20% by weight, based on the total weight of the particle coating composition.

[0104] Leveling Agent The particle coating composition of the present invention preferably comprises a leveling agent. Examples of suitable leveling agents include copolymers of methyl acrylate and butyl acrylate. Suitable leveling agents are commercially available, such as BLC701B from Ningbo South Sea Chemical Co. Ltd. and WK701 from Ningbo Wecan Chemical Co. Ltd. The leveling agent enhances the melt flow properties of the composition and helps to remove surface defects during curing.

[0105] If present, the amount of leveling agent present in the particle composition of the present invention is preferably from 0.01 to 5 wt. %, more preferably from 0.1 to 3 wt. %, and even more preferably from 0.5 to 1.5 wt. %, based on the total weight of the particle coating composition.

[0106] Additives The particle coating composition of the present invention optionally comprises one or more additives. Examples of additives optionally present in the composition of the present invention include metal phosphates, metal borates, amino alcohols, adhesion promoters, gloss modifiers, drying agents, waxes, ethylene bisstearamide (EBS), antioxidants, rheology additives, matting agents and surface conditioners. Preferred additives present in the particle coating composition of the present invention are gloss modifiers, rheology modifiers, surface conditioners, matting agents and mixtures thereof. Representative examples of suitable rheology modifiers are hydrogenated castor oil and low melting polyethylene wax. The additional additives are preferably present in an amount of 0-10 wt%, more preferably 0.1-5 wt%, even more preferably 0.2-4 wt%, and particularly preferably 0.5-3 wt%, based on the total weight of the particle coating composition.

[0107] composition A preferred particle coating composition of the present invention comprises: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazoline ring; (iii) filler; (iv) a degassing agent, preferably benzoin; (v) flow additives; (vi) preferably a color pigment; and (vii) leveling agents, Including, Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0108] Further preferred particle coating compositions of the present invention include: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazoline ring; (iii) a filler selected from barium sulfate, preferably precipitated barium sulfate, mica, talc, wollastonite (calcium metasilicate), glass flake, nepheline, kaolin, dolomite, diatomite, boron nitride, alumina, aluminum hydroxide, and mixtures thereof; (iv) benzoin; (v) flow additives; (vi) colour pigments; and (vii) leveling agents, Including, Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0109] Yet another preferred particle coating composition of the present invention comprises: (i) an epoxy resin selected from bisphenol A type epoxy resins, bisphenol F type epoxy resins, novolac-modified bisphenol A type epoxy resins, isocyanate-modified bisphenol A type epoxy resins, cresol novolac type epoxy resins, O-cresol epoxy resins, silane-modified bisphenol A type epoxy resins, rubber-modified bisphenol A type epoxy resins, silicone-modified bisphenol A type epoxy resins, and mixtures thereof; (ii) a curing agent, the curing agent containing an imidazoline ring; (iii) a filler selected from barium sulfate, preferably precipitated barium sulfate, mica, talc, wollastonite (calcium metasilicate), glass flake, nepheline, kaolin, dolomite, diatomite, boron nitride, alumina, aluminum hydroxide, and mixtures thereof; (iv) benzoin; (v) flow additives; (vi) colour pigments; and (vii) Leveling agent Including, The total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40-99 wt %, based on the total weight of the particle coating composition.

[0110] Further preferred particle coating compositions of the present invention include: (i) 38 to 95% by weight, preferably 40 to 95% by weight, more preferably 50 to 95% by weight, and even more preferably 60 to 90% by weight of an epoxy resin; (ii) 1 to 35% by weight, preferably 1.5 to 20% by weight, more preferably 2 to 15% by weight, of a curing agent based on the amount of epoxy resin, the curing agent containing an imidazoline ring; (iii) 0.01 to 60% by weight, preferably 1.5 to 50% by weight, more preferably 10 to 38% by weight of a filler; (iv) 0.15 to 0.45% by weight, preferably 0.17 to 0.4% by weight, more preferably 0.2 to 0.35% by weight of a degassing agent, preferably benzoin; Including, All weight percentages herein are based on the total weight of the particulate composition unless otherwise specified.

[0111] In particularly preferred particle coating compositions of the present invention, the hardener is 2-phenyl-2-imidazoline.

[0112] Preferred particle coating compositions of the present invention have a pigment volume concentration (PVC) of 0 to 25, more preferably 7 to 18, even more preferably 9 to 13, calculated for example from the theoretical density of the components of the coating and their weight percentages.

[0113] Some particularly preferred particle coating compositions of the present invention are: - 65.9% by weight of bisphenol F based epoxy, 4.1% by weight of 2-phenylimidazoline, 8.4% by weight of pigment, 20.2% by weight of precipitated barium sulfate, 1.4% by weight of benzoin, flow agents and additives, - Type 3 epoxy 64.8% by weight, 2-phenylimidazoline 5.2% by weight, pigment 8.4% by weight, precipitated barium sulfate 20.2% by weight, benzoin, flow agents and additives 1.4% by weight, - Type 3 epoxy 64.2% by weight, 2-phenylimidazoline 5.8% by weight, pigment 8.4% by weight, precipitated barium sulfate 20.2% by weight, benzoin, flow agents and additives 1.4% by weight, - Type 3 epoxy 66.5% by weight, 2-phenylimidazoline 3.5% by weight, precipitated barium sulfate 27.1% by weight, organic green pigment 1.5% by weight, benzoin, flow agents and additives 1.4% by weight, - Type 3 epoxy 66.5% by weight, 2-phenylimidazoline 3.5% by weight, carbon black 1.1% by weight, precipitated barium sulfate 27.5% by weight, benzoin, flow agents and additives 1.4% by weight, - Type 3 epoxy 66.5% by weight, 2-phenylimidazoline 3.5% by weight, pigment 8.4% by weight, kaolin 20.2% by weight, benzoin, flow agents and additives 1.4% by weight, - Type 3 epoxy 66.5% by weight, 2-phenylimidazoline 3.5% by weight, pigment 8.4% by weight, precipitated barium sulfate 10.1% by weight, kaolin 10.1% by weight, benzoin, flow agents and additives 1.4% by weight, - Type 3 Epoxy 66.5% by weight, 2-Phenylimidazoline 3.5% by weight, Pigment 8.4% by weight, Talc 10.1% by weight, Kaolin 10.1% by weight, Benzoin, Flow Agents and Additives 1.4% by weight - 66.5% by weight of Type 3 epoxy, 3.5% by weight of 2-phenylimidazoline, 8.4% by weight of pigment, 20.2% by weight of precipitated barium sulfate, 1.4% by weight of benzoin, flow agents and additives, and - Type 3 epoxy 66.5% by weight, 2-phenylimidazoline 3.5% by weight, titanium dioxide 25% by weight, precipitated barium sulfate 3.6% by weight, benzoin, flow agents and additives 1.4% by weight.

[0114] The particle coating composition of the present invention preferably provides a coating that is electrically insulating, i.e., has high electrical resistance and high voltage resistance. Preferably, the particle coating composition of the present invention provides a coating that can withstand DC 1000V with a resistance of >500MΩ. Preferably, the particle coating composition of the present invention provides a coating that can withstand DC 2700V and has a maximum leakage current of 0.1 mA or less.

[0115] It is a feature of the present invention that the particle coating composition provides a coating that is electrolyte resistant, thus providing a coating that is electrically insulating after exposure to an electrolyte.

[0116] Preferably, the particle coating composition of the present invention provides a coating having insulation resistance after immersion in an electrolyte according to the criteria set forth in the Examples herein, withstanding DC 1000V without destruction of the coating with a resistance of >500MΩ and / or a resistance below the limit of 500MΩ. Preferably, the particle coating composition of the present invention provides a coating having voltage resistance after immersion in an electrolyte according to the criteria set forth in the Examples herein, withstanding DC 2700V with a maximum leakage current of 0.1 mA or less and / or with a slight current leakage above the limit of 1 mA at voltages below DC 2700V. Preferably, the particle coating composition of the present invention provides a coating having insulation and voltage resistance after immersion in an electrolyte according to the criteria set forth in the Examples herein, withstanding DC 1000V without destruction of the coating with a resistance of >500MΩ and / or a resistance below the limit of 500MΩ, withstanding DC 2700V with a maximum leakage current of 0.1 mA or less and / or with a slight current leakage above the limit of 1 mA at voltages below DC 2700V.

[0117] Preferably, the particle coating composition provides a coating having insulation resistance after immersion in an electrolyte according to the criteria described in the Examples herein, withstanding DC 1000V with a resistance of >500MΩ. Preferably, the particle coating composition provides a coating having voltage resistance after immersion in an electrolyte according to the criteria described in the Examples herein, withstanding DC 2700V, with a maximum leakage current of 0.1 mA or less. Preferably, the particle coating composition provides a coating having insulation and voltage resistance after immersion in an electrolyte according to the criteria described in the Examples herein, withstanding DC 1000V with a resistance of >500MΩ, and withstanding DC 2700V, with a maximum leakage current of 0.1 mA or less.

[0118] It is yet another feature of the present invention that the particle coating composition provides a coating having good adhesion to a substrate, preferably a metal substrate, such as an aluminum substrate, and good adhesion to a structural adhesive. Preferably, the particle coating composition provides a coating that passes the cross-cut test described in ISO 2409:2013(E).

[0119] It is yet another feature of the present invention that the particle coating composition provides a coating that is resistant to discoloration by electrolytes. Preferably, the coating exhibits only slight discoloration when immersed in an electrolyte, for example, as described in the Examples section herein.

[0120] A further feature of the present invention is that the particle coating composition provides a coating that is water resistant, i.e., does not lose adhesion and does not significantly swell or form swelling areas when exposed to water, even at elevated temperatures.

[0121] container The present invention also relates to a container containing the above-mentioned particle coating composition. Suitable containers include cardboard boxes lined with plastic bags, and plastic bags (so-called "big bags").

[0122] manufacturing The present invention also relates to a method for preparing a particle coating composition as described above, comprising: (i) mixing an epoxy resin, a hardener, the hardener including an imidazoline ring, a filler, and a degassing agent to form a mixture; and (ii) extruding the mixture to form particles. Includes.

[0123] The extruded particles can be of any shape, for example, spherical particles, chips or flakes. A preferred method of the present invention further comprises milling the extruded particles to form a powder. Milling can be carried out in any conventional mill to a particle size found to be most suitable for powder applications. Another preferred method of the present invention further comprises sieving the milled particles.

[0124] Thus, a preferred method of the invention comprises: (i) mixing an epoxy resin, a hardener (wherein the hardener comprises an imidazoline ring), a filler and a degassing agent to form a mixture; (ii) extruding the mixture to form particles; (iii) grinding the extruded particles to form ground particles; and (iv) Sifting the ground particles. Includes.

[0125] In a particularly preferred method of the invention, the curing agent is 2-phenyl-2-imidazoline.

[0126] After pulverization, it is preferable to carry out sieving to remove coarse particles.

[0127] If necessary, add a flow agent (eg, fume silica or aluminum oxide) during grinding and / or sieving.

[0128] Any conventional mixing, extrusion and grinding methods can be used. Preferred extrusion conditions are conventional and are generally kept low, e.g., below 140°C, to avoid premature curing. Particle Size Distribution D of the Particulate Coating Composition 50 The preferred particle size D is in the range of 10 to 120 μm, and more preferably 15 to 100 μm. 50 is at least 20 or 25 μm, advantageously not exceeding 80 μm, for example 30 to 70 μm. Generally, particle size can be determined using a Malvern particle size analyzer.

[0129] Substrate and Coating Applications The present invention also relates to a method for coating a substrate with a particulate coating composition as described above, the method comprising: i) applying a particle coating composition to a substrate; and ii) curing the particle coating composition; Includes.

[0130] Optionally, the substrate is pretreated, for example degreased, desalted, shot or grit blasted, dedusted, etc., prior to application of the particulate coating composition.

[0131] In some methods of the present invention, the substrate is preheated and the heat in the substrate cures the coating.

[0132] Thus, some methods of the invention include: i) preheating the substrate, e.g., to a temperature above the cure temperature of the particle coating composition; ii) applying a particulate coating composition to the preheated substrate; and iii) curing the particle coating composition; Includes.

[0133] The particle coating composition of the present invention may be applied to a substrate by any conventional particle coating method, such as a powder coating method, for example, by electrostatic spraying or fluidized bed. A cold or preheated substrate may be coated, for example, in a spray booth, or the preheated substrate is immersed in a fluidized bed of powder. Preheating is preferably maintained for a time sufficient to heat the substrate to a temperature above the melting temperature of the powder and for the coating to flow, melt, and harden into a continuous coating. Coating techniques are well known in the art and familiar to those skilled in the art. Electrostatic spraying is preferred.

[0134] The present invention also relates to the use of a particulate coating composition as described above for coating a substrate, preferably a metal substrate, such as aluminium, preferably having a dry thickness of 60 to 250 microns, for example 80 to 200 microns, in particular 90 to 150 microns.

[0135] The present invention also relates to a coating comprising the above-mentioned particle coating composition. Preferably, the coating is cured. Alternatively, the present invention relates to a coating obtainable by spraying or dipping the above-mentioned particle coating composition and curing.

[0136] The particle coating composition of the present invention can be used to form a single layer coating or can be part of a multi-layer structure.The particle coating composition of the present invention is preferably used to form a first layer or base layer on a substrate, such as a battery cell.Preferably, the coating of the present invention is the top layer or outermost layer that can be exposed to electrolyte.

[0137] hardening Once the substrate is coated with the particle coating composition of the present invention, the coating is preferably cured. Curing can be accomplished by continued heating, subsequent heating, or residual heat in the substrate. Additionally or alternatively, the particle coating composition of the present invention may be cured by placing the substrate in a post-cure oven. The heating process allows the particles to melt, fuse, and then harden.

[0138] The particle coating composition is preferably free flowing during the curing operation. Advantageously, this results in a smooth, uniform finish. The thickness of the cured coating is preferably 60 to 250 microns, for example 80 to 200 microns, especially 90 to 150 microns.

[0139] The coating formed from the particle coating composition of the present invention is preferably electrically insulating, i.e., has high electrical resistance and high voltage resistance. Preferably, the coating formed from the particle coating composition of the present invention is resistant to DC 1000V with a resistance of >500MΩ. Preferably, the coating formed from the particle coating composition of the present invention is resistant to 2700V and has a maximum leakage current of 0.1mA or less.

[0140] A feature of the present invention is that the coating formed from the particle coating composition of the present invention is electrolyte resistant. Thus, the coating is electrically insulating after exposure to electrolyte. Preferably, the coating has insulation resistance according to the criteria described in the examples of this specification after immersion in electrolyte, and withstands DC1000V with a resistance of >500MΩ. Preferably, the coating has voltage resistance according to the criteria described in the examples of this specification after immersion in electrolyte, and withstands 2700V and has a maximum leakage current of 0.1mA or less. Preferably, the coating has insulation and voltage resistance according to the criteria described in the examples of this specification after immersion in electrolyte, and withstands DC1000V with a resistance of >500MΩ, and withstands 2700V and has a maximum leakage current of 0.1mA or less.

[0141] Yet another feature of the present invention is that the coating formed from the particle coating composition of the present invention has good adhesion to substrates, preferably metal substrates, such as aluminum substrates, and structural adhesives. Preferably, the coating formed from the particle coating composition of the present invention is subjected to the cross-cut test described in ISO 2409:2013(E).

[0142] Yet another feature of the present invention is that the coatings formed from the particle coating compositions of the present invention are resistant to discoloration by electrolytes. Preferably, the coatings exhibit only slight discoloration when immersed in an electrolyte, for example, as described in the Examples section herein.

[0143] A further feature of the present invention is that the coatings formed from the particle coating compositions of the present invention are water resistant, i.e., they do not loosen adhesion or swell significantly or form blisters when exposed to water, even at elevated temperatures.

[0144] Substrates and articles The present invention also relates to a substrate coated with the above-mentioned particle coating composition or the above-mentioned coating. The particle coating composition of the present invention can be applied to any substrate. The preferred substrate is a metal, and even more preferably, the substrate is aluminum. Particularly preferably, the substrate is an aluminum surface of a battery cell, and particularly preferably, the aluminum surface of a battery cell present in a battery assembly, for example, a battery assembly of an electric vehicle.

[0145] The substrate, such as the aluminum surface of a battery cell, may be partially or completely coated with the particle coating composition or coating of the present invention. However, preferably substantially all of the substrate is coated with the particle coating composition or coating of the present invention. In the case of a battery cell, this preferably includes the entire outer wall of the cell, except for the electrical contacts.

[0146] The present invention also relates to a battery assembly including at least one battery cell, the at least one battery cell having a coating formed on at least one surface thereof, the coating comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazoline ring; (iii) filler; and (iv) optionally a degassing agent, preferably benzoin The composition is formed from a composition comprising:

[0147] Preferably, the battery assembly includes a plurality of battery cells, the battery cells having a coating formed on at least one surface, the coating being formed from a composition described herein.

[0148] A preferred battery assembly includes a coating formed from the preferred particle coating composition described above.

[0149] Further preferred battery assemblies include the preferred coatings described above.

[0150] Battery assemblies, uses and methods The present invention also relates to a battery assembly including at least one battery cell, the at least one battery cell having a coating formed on at least one surface thereof, the coating comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent comprising an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin The composition is formed from a composition comprising:

[0151] Preferably, the battery assembly includes a plurality of battery cells, the battery cells having a coating formed on at least one surface, the coating being formed from a composition described herein.

[0152] The present invention also relates to the use of a particle coating composition for forming an electrolyte-resistant coating on at least one surface of a substrate, preferably a battery cell, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Here, the total amount of the epoxy binder system including the epoxy resin and the curing agent is preferably 40 to 99% by weight based on the total weight of the particle coating composition.

[0153] The present invention also relates to the use of a particle coating composition for protecting a substrate, in particular a battery cell, from an electrolyte, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0154] The present invention also relates to the use of a particulate coating composition for coating at least one aluminum surface of a battery cell, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt %, based on the total weight of the particle coating composition.

[0155] The present invention also relates to the use of a particle coating composition for forming at least a base layer on a battery cell, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Preferably, the total amount of the epoxy binder system, including the epoxy resin and the hardener, is 40 to 99 wt % based on the total weight of the particle coating composition.

[0156] The present invention also relates to the use of a particle coating composition for coating a battery cell, comprising: (i) an epoxy resin, (ii) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (iii) filler; and (iv) a degassing agent, preferably benzoin; Here, the total amount of the epoxy binder system including the epoxy resin and the curing agent is preferably 40 to 99% by weight based on the total weight of the particle coating composition.

[0157] The present invention also relates to a method for protecting a surface from electrolyte damage, the method comprising: (a) applying a particle coating composition onto a surface; and (b) curing the coating composition to obtain a coating. Including, The particle coating composition comprises: (v) epoxy resins, (vi) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (vii) filler; and (viii) a degassing agent, preferably benzoin; Including, Preferably, the total amount of the epoxy binder system (the system including the epoxy resin and the hardener) is 40 to 99 wt % based on the total weight of the particle coating composition.

[0158] The present invention also relates to a method for maintaining electrical insulation of a coating on a substrate after exposure of the coating to (e.g., contact with) an electrolyte, the method comprising: (a) applying a particle coating composition onto a surface; and (b) curing the coating composition to obtain a coating; Including, The particle coating composition comprises: (v) epoxy resins, (vi) a curing agent, the curing agent containing an imidazole, imidazoline or imidazolidine ring, preferably an imidazoline ring; (vii) filler; and (viii) a degassing agent, preferably benzoin Including, Here, preferably, the total amount of the epoxy binder system (the system includes an epoxy resin and a hardener) is 40-99 wt % based on the total weight of the particle coating composition.

[0159] The preferred battery assemblies, uses and methods include a coating formed from the preferred epoxy resin, a filler, and a degassing agent, as described above in connection with the composition itself.

[0160] The preferred battery assemblies, uses and methods include a coating formed from a curing agent that includes an imidazole, imidazoline or imidazolidine ring. More preferably, the curing agent present in the particle coating composition includes an imidazoline ring. The imidazoline ring may be a 2-imidazoline, a 3-imidazoline or a 4-imidazoline. Preferably, the imidazoline ring is a 2-imidazoline.

[0161] The imidazole, imidazoline or imidazolidine ring present in the present curing agent may be unsubstituted or substituted.Preferably, the imidazole, imidazoline or imidazolidine ring is substituted.Any number of substituents may be present, more preferably, one or two substituents are present, and even more preferably, one substituent is present.

[0162] When substituted, imidazole, imidazoline or imidazolidine ring can be substituted at any position.Preferably, imidazole, imidazoline or imidazolidine ring is substituted at 2-position, for example, preferred hardener comprises imidazoline ring substituted at 2-position.Optionally, imidazole, imidazoline or imidazolidine ring present in hardener present in particle coating composition of the present invention is dimer, for example, is connected by alkylene linker between two 2-position of imidazole, imidazoline or imidazolidine ring.

[0163] Examples of suitable substituents which may be present on the imidazole, imidazoline or imidazolidine ring include aromatic substituents, C 1 ~C 12 Alkyl Substituents, C 1 ~C 6 Alkylene Substituents, Alcohols, Amines, Halides, C 1 ~C 6 Preferred substituents include aromatic substituents (e.g., phenyl or benzyl) and C 1 ~C 12Alkyl substituents (e.g., methyl) are included. More preferred substituents include aromatic substituents (e.g., phenyl or benzyl) and C 2 ~C 12 The aromatic substituents include alkyl groups. Even more preferably, the imidazole, imidazoline or imidazolidine ring has an aromatic substituent. Examples of suitable aromatic substituents include phenyl and heterocycles such as pyridine, imidazole, furan and thiophene. The preferred aromatic substituent is phenyl, especially unsubstituted phenyl.

[0164] The imidazole, imidazoline or nitrogen atom of the imidazoline ring may be substituted or unsubstituted. Examples of suitable substituents include C 1 ~C 12 These include alkyl groups, alkyl alcohols and alkyl amines. The nitrogen atom is preferably unsubstituted.

[0165] When phenyl is present as a substituent on an imidazole, imidazoline or imidazoline ring, the phenyl may be unsubstituted or substituted. Examples of suitable substituents include C 1 ~C 6 Alkyl, C 1 ~C 6 These include alkoxy, nitrile, hydroxyl, halide, thiol, and amine. Phenyl substituents may have one or several substituents located at any position on the aromatic ring. Preferably, phenyl present as a substituent is unsubstituted.

[0166] Particularly preferred particle coating compositions include a curing agent that includes an imidazoline ring, and even more preferably includes a curing agent that includes a 2-imidazoline ring. Particularly preferred curing agents present in the coating composition include (e.g., consist of) a 2-imidazoline ring substituted at the 2-position.

[0167] Even more preferably, the substituents are aromatic (e.g., phenyl) or C 1 ~C 12It is an alkyl substituent (eg, methyl).

[0168] Even more preferably, the substituents are aromatic (e.g., phenyl or benzyl) or C 2 ~C 12 It is an alkyl substituent.

[0169] It is particularly preferred that the hardener present comprises (eg consists of) 2-phenyl-2-imidazoline (Cas number 936-49-2). [ka]

[0170] The hardener preferably comprises 2-phenyl-2-imidazoline, for example at >50% by weight of the hardener, more preferably >75% by weight, even more preferably >90% by weight, even more preferably >95% by weight.

[0171] The 2-phenyl-2-imidazoline preferably present in the particle coating composition preferably has a purity of 98% or greater, more preferably 99% or greater.

[0172] Suitable curing agents that contain an imidazole, imidazoline or imidazolidine ring are commercially available as described above.

[0173] It will be understood that the hardener and epoxy resin must react to cure the coating. The appropriate amount of hardener and epoxy resin will depend on the relative number of reactive groups, i.e., epoxide in the epoxy resin and amine in the hardener. Generally speaking, the amount of hardener present (wt%) is preferably 1-35 wt%, more preferably 1.5-20 wt%, and even more preferably 2-15 wt%, based on the amount of epoxy resin present on a wt% basis.

[0174] It is preferred that these components are mixed in a ratio such that the hardener is present in a stoichiometric amount of 80-120%, more preferably 90-115%, and even more preferably 100-110%, based on the number of reactive groups in the hardener relative to the number of reactive groups present in the epoxy resin.

[0175] Preferably, the coating composition is as described above with respect to the coating composition per se.

[0176] The invention will now be described with reference to the following non-limiting examples. EXAMPLES

[0177] raw material The polymers and compounds used in the examples were all commercially available and are summarized in the table below.

[0178] [Table 1-1] [Table 1-2]

[0179] Powder coating sample preparation The powder coatings were prepared using the following procedure: (1) The raw materials were charged into a mixing tank according to the corresponding weight percentages for premixing as shown in the table below. The amounts of ingredients are specified in wt% unless otherwise specified. Mixing was carried out in two stages in a mixing tank: in the first stage the mixing time was 3-5 min, the rotation speed was 700 r / min, and the working temperature was 20-30 °C; in the second stage the mixing time was 3-5 min, the rotation speed was 900 r / min, and the working temperature was 20-30 °C. (2) The premixed raw materials were homogeneously melted, mixed, dispersed and extruded using a twin-screw extruder. The temperature of the extruder was 90-110°C, and the screw frequency was controlled at 30-50Hz. The extruded mixture was then tableted and crushed. (3) The crushed material was graded and crushed by ACM mill. The disk frequency was 25-35Hz and the classifier frequency was 25-35Hz. (4) The milled material was classified into a powder coating having a particle size D50 of 30-50 microns. (5) The compositions of the powder coatings prepared for testing are summarized in the table below, where the amounts specified are in wt % unless otherwise specified.

[0180] Preparation of test samples The test panels were prepared according to the following steps: 1. The panels were AL 6036 type aluminum panels with a panel size of 50x30x0.8mm. The panels were pre-treated sequentially by immersion in alkaline or acidic solutions, a rinse bath, an acid cleaning bath, a rinse bath, and then a treatment to ensure that the panels were chrome-free, after which they were dried in an oven at object temperatures up to 100°C. 2. Protective tape was applied to the bottom rim (approximately 0.5 x 2 cm) on the back of each panel to avoid coating this area. 3. In a cleaned spray booth, the spray gun was thoroughly cleaned with compressed air. The spray pattern of the gun was checked to ensure that it deposited a uniform layer of powder across the test panel. 4. Each panel was sprayed individually for the length of time necessary to achieve the specified target thickness of 100-130μm. 5. The panel was hung in a curing oven and cured using an object temperature of 200°C / 10min. 6. The protective tape was removed after the panel had cooled. 7. Coating thickness was measured. The thickness of the panels used in the test was 100-130 μm. 8. For adhesion testing, the panels were tested prior to exposure to the electrolyte. 9. For insulation and voltage testing, the panels were tested before exposure to the electrolyte and after immersion in the electrolyte. 10. For discoloration testing, the panels were exposed to electrolyte and then tested.

[0181] electrolyte soak 0.5 liters of electrolyte was prepared, the composition of the electrolyte being: Ethylene carbonate (EC), diethyl carbonate (DEC) and dimethyl carbonate (DMC) mixed in a weight or volume ratio of EC / DEC / DMC=2 / 1 / 7; lithium hexafluorophosphate (1.1 mol); additives vinylene carbonate (VC)=2%, 1,3-propane sultone=1% Half of the coated panel was immersed in the electrolyte and the other half of the panel was left in air. The container was sealed and left for 7 days. After 7 days, the panel was removed from the electrolyte, dried, and then tested as described below. These test conditions represent extreme conditions, much more severe than those to which the coating would be exposed in a battery assembly where contact with the electrolyte occurs through spillage.

[0182] Test Method Adhesion test The samples were tested according to the cross-cut test as described in ISO 2409:2013(E). In the results, Gt0 is the best and Gt5 is the worst. / = not tested

[0183] Insulation test The samples were tested according to the following procedure. Three parallel samples were tested for each composition: 1. Establish the connection: Connect the power supply and turn on the device. The coated panel is placed on a thick rubber pad to ensure there is no leakage current when voltage is applied. A clip is connected to the bare metal back bottom (previously covered by protective tape) and the test electrode from the device is connected to the coated top part of the panel via the profiling checker in step 3. 2. Parameter setting: DC1000V, test time = 60 seconds, lower limit resistance set to 500MΩ. Voltage rises from 0 to 1000V in 1 second. 3. A profiling checker, i.e. a conductive metal panel having the same shape as the coated panel but slightly smaller in size (approximately 5 mm shorter in all directions), is placed on top of the coated panel to be tested. When a voltage is applied, the profiling checker is pressed with a force of ≥ 1.5 kgf to ensure that the potential breakdown point (of the coated panel) is in the non-edge area (the area covered by the profiling checker), and the insulation resistance is tested using the test electrodes through the profiling checker.

[0184] Insulation test pass criteria: If the sample has a resistance >500MΩ and can withstand 1000V DC: O = Passes the test criteria Θ = No damage to the sample, but it withstands below the limit of 500MΩ x = No withstand voltage test, no insulation resistance test

[0185] Voltage testing The samples were tested according to the following procedure. Three parallel samples were tested for each composition: 1. Establish the connections: Connect the power supply and turn on the device. The coated panel is placed on a thick rubber pad to ensure there is no leakage current when voltage is applied. Connect the clip to the bare metal back bottom (previously covered by protective tape) and connect the test electrodes from the device in step 3 to the coated top part of the panel via the profiling checker. 2. Parameter settings: DC2700V, test time = 60 seconds, maximum leakage current is set to 1mA or less. The voltage rises from zero to 2700V in 1s. 3. Place the profiling checker on the coated panel to be tested. When voltage is applied, press the profiling checker with a force of ≥ 1.5 kgf to ensure that the potential breakdown point (of the coated panel) is in the non-edge area (the area covered by the profiling checker), and test the leakage current using the test electrodes through the profiling checker.

[0186] Voltage test pass criteria: The sample has a maximum leakage current of 0.1mA or less and can withstand a resistance of 2700V: O = Passes the test criteria Small current leakage of more than 1mA at voltages below Θ=2.7kV x = Destruction of the coating film

[0187] Voltage test and insulation test are typically performed on the same panel because the steps are the same except for the parameter settings. If the coating is damaged during the voltage test, the insulation test cannot be performed on the same panel.

[0188] Discoloration after immersion The coatings were visually inspected for discoloration after immersion. This was done before insulation and voltage testing. The evaluation criteria applied were as follows: O = slight discoloration of the immersed coating Θ = Significant discoloration of the immersed coating x = Significant discoloration of the entire coating

[0189] Example 1 - Effect of hardener The powder coatings listed in Table 1 below were prepared along with seven comparative examples. The comparative examples used various curing agents other than those containing an imidazole, imidazoline or imidazolidine ring. The results of the testing are also shown in Table 1. All examples passed insulation and voltage tests prior to immersion in the electrolyte.

[0190] The results in Table 1 show that when the curing agent present in the particle coating composition contains an imidazole, imidazoline or imidazolidine ring (e.g., 2-phenyl-2-imidazoline), the resulting coating adheres well to the substrate and can withstand exposure to an electrolyte. After immersion in an electrolyte for 7 days, an extreme test condition, the coating made from the composition containing 2-phenyl-2-imidazoline still passed the voltage test and did not break down in the insulation test. In contrast, coatings made from compositions containing various other curing agents did not pass the voltage test after immersion in the electrolyte and therefore could not be subjected to the insulation test. The level of discoloration was also more severe in coatings containing curing agents other than 2-phenyl-2-imidazoline.

[0191] The results in Table 1, specifically Examples 1-5, also show that different types of epoxy resins can be successfully used in the particle coating composition of the present invention.

[0192] Examples 9 and 10 in Table 1 show particularly strong performance. In these examples, the ratio of 2-phenyl-2-imidazoline to epoxy resin is higher than in some of the other examples. It is believed that the relatively higher ratio of hardener can result in a higher density of crosslinks in the final coating and thus the improved performance results observed.

[0193] [Table 2]

[0194] [Table 3]

[0195] Example 2 - Effect of total amount of epoxy resin in coating composition The powder coatings listed below in Table 2 were prepared. All examples passed the insulation and voltage tests prior to immersion in the electrolyte. None of the examples were tested for adhesion prior to immersion.

[0196] [Table 4]

[0197] The results in Table 2 show that the particle coating compositions of the present invention can include a wide range of epoxy resin and hardener combinations. The examples show that particle coating compositions containing 38-85.5 wt. % epoxy resin and 2-5 wt. % hardener all produce coatings that pass insulation and voltage tests, even after exposure to an electrolyte for 7 days. The examples also show that the particle compositions of the present invention can include a range of fillers, specifically 0.2-50.2 wt. % filler, and still produce coatings that pass insulation and voltage tests, even after exposure to an electrolyte.

[0198] Example 3 - Effect of fillers on coating composition The powder coatings described in Table 3 below were prepared. The results of the testing are also shown in Table 3. All examples passed the insulation and voltage tests before immersion in the electrolyte. All coating films had an adhesion of Gt0 before immersion.

[0199] The results in Table 3 show that a wide range of fillers can be used in the particle coating compositions of the present invention. Compositions containing a single filler and compositions containing a mixture of fillers performed well. When a filler is present, coatings made from the particle coating compositions of the present invention pass insulation and voltage tests, even after exposure to electrolytes.

[0200] Example 4 - Effect of filler combinations and pigments in coating compositions The powder coatings described in Table 4 below were prepared. The results of the tests are also shown in Table 4. All examples passed the insulation test and voltage test before immersion in the electrolyte. The results in Table 4 show that both organic and inorganic pigments can be used in the particle compositions of the present invention.

[0201]

Table 5

[0202]

Table 6

[0203]

Table 7

Claims

1. A particle coating composition, preferably a powder coating composition: (i) epoxy resin, (ii) a curing agent, the curing agent comprising an imidazoline ring; (iii) Filling material; and (iv) Degassing agent, preferably benzoin, Includes, The total amount of the epoxy binder system is 40 to 99% by weight based on the total weight of the particle coating composition, and the system comprises the epoxy resin and the curing agent. Particle coating composition.

2. The composition according to claim 1, wherein the curing agent comprises 2-phenyl-2-imidazoline, or more preferably 2-phenyl-2-imidazoline.

3. The composition according to claim 1 or 2, wherein the epoxy resin has an epoxy equivalent (EEW) of 200 to 1950 g / eq, preferably 200 to 1300 g / eq, and more preferably 400 to 1300 g / eq.

4. The composition according to claim 1 or 2, wherein the epoxy resin is selected from bisphenol A epoxy resins, novolac-modified bisphenol A epoxy resins, bisphenol F epoxy resins, isocyanate-modified bisphenol A epoxy resins, and mixtures thereof, preferably selected from bisphenol A epoxy resins, novolac-modified bisphenol A epoxy resins, and mixtures thereof, and more preferably a bisphenol A epoxy resin.

5. The composition according to claim 1 or 2, wherein the total amount of the epoxy binder system is 50 to 95% by weight, more preferably 60 to 90% by weight, based on the total weight of the particle coating composition, and the system comprises the epoxy resin and the curing agent.

6. The composition according to claim 1 or 2, comprising 38 to 99% by weight, preferably 40 to 99% by weight, more preferably 50 to 95% by weight, even more preferably 55 to 95% by weight, and even more preferably 60 to 90% by weight of epoxy resin, based on the total weight of the particle coating composition, and / or comprising 1 to 35% by weight, more preferably 1.5 to 20% by weight, and even more preferably 2 to 15% by weight of curing agent, based on the amount of epoxy resin.

7. The composition according to claim 1 or 2, wherein the filler is selected from barium sulfate, preferably precipitated barium sulfate, mica, talc, wollastonite (calcium metasilicate), glass flakes, nepheline, kaolin, dolomite, diatomite, boron nitride, alumina, aluminum hydroxide, and mixtures thereof, more preferably barium sulfate, preferably precipitated barium sulfate, kaolin, and mixtures thereof.

8. The composition according to claim 1 or 2, comprising 0.01 to 60% by weight, more preferably 1.5 to 50% by weight, and even more preferably 10 to 38% by weight of a filler, based on the total weight of the particle coating composition.

9. The composition according to claim 1 or 2, comprising 0.15 to 0.45% by weight, more preferably 0.17 to 0.4% by weight, and even more preferably 0.2 to 0.35% by weight of a degassing agent, based on the total weight of the particle coating composition.

10. A container containing the particle coating composition according to claim 1 or 2.

11. A method for preparing the particle coating composition according to claim 1 or 2: (i) Mixing epoxy resin, curing agent, filler and degassing agent to form a mixture, the curing agent containing an imidazoline ring; and (ii) Extruding the mixture to form particles. Methods that include...

12. Use of the particle coating composition according to claim 1 or 2 for coating a substrate, preferably a metal substrate, such as aluminum.

13. A method for coating a substrate, preferably a metal substrate, such as aluminum, with the particle coating composition described in claim 1 or 2: (i) Applying the particle coating composition to the substrate, and (ii) Curing the particle coating composition. Methods that include...

14. A coating, preferably a cured coating, comprising the particle coating composition according to claim 1 or 2.

15. A substrate, preferably a metal substrate, such as aluminum, coated with the particle coating composition according to claim 1 or 2, or coated with a coating comprising the particle coating composition according to claim 1 or 2, preferably a cured coating.

16. A battery assembly comprising at least one battery cell, wherein the at least one battery cell has a coating formed on at least one surface, the coating being: (i) epoxy resin, (ii) Curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin A battery assembly formed from a composition containing the following:

17. The battery assembly according to claim 15, wherein the composition is the composition according to claim 1 or 2.

18. The use of a particle coating composition for forming an electrolyte-resistant coating on at least one surface of a substrate, preferably a battery cell, wherein the particle coating composition is: (i) epoxy resin, (ii) Curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin Includes, use.

19. The use of a particle coating composition for protecting a substrate, particularly a battery cell, from an electrolyte, wherein the particle coating composition is: (i) epoxy resin, (ii) Curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin Includes, use.

20. Use of a particle coating composition for coating at least one aluminum surface of a battery cell, wherein the particle coating composition is: (i) epoxy resin, (ii) Curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin Includes, use.

21. The use of a particle coating composition for forming at least one substrate layer on a battery cell, wherein the particle coating composition is: (i) epoxy resin, (ii) Curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin Includes, use.

22. The use of a particle coating composition for coating a battery cell, wherein the particle coating composition is: (i) epoxy resin, (ii) A curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin Includes, use.

23. The use according to claim 17, wherein the composition is the composition according to claim 1 or 2.

24. A method for protecting a surface from electrolyte damage: (a) Applying the particle coating composition to the surface, and (b) To obtain a coating by curing the coating composition. Includes, The aforementioned particle coating composition is: (i) epoxy resin, (ii) A curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin Methods that include...

25. A method for maintaining the electrical insulation of a coating on a substrate after exposure (e.g., contact) of the coating to an electrolyte, comprising: (a) Applying the particle coating composition to the surface, and (b) To obtain a coating by curing the coating composition. The particle coating composition includes: (i) epoxy resin, (ii) Curing agent, the curing agent comprising an imidazole, imidazoline, or imidazolidine ring, preferably an imidazoline ring; (iii) Fillers; and (iv) Degassing agent, preferably benzoin Methods that include...

26. The method according to claim 21 or 22, wherein the composition is the composition according to claim 1 or 2.

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