Multi-coating method for manufacturing a material with improved insulating and heat-insulating properties

Abstract

The present invention relates to a multilayer coating method for manufacturing a material having insulating or thermal insulation capabilities by first applying a coating composition comprising an inorganic binder component, an organic binder component, a phosphorus-based flame retardant component, and a graphite-based filler onto a target material to form a first coating layer, and then directly coating and laminating the coating composition, an insulating material, or a thermal insulation material a second or more times on top of the first layer without adding any adhesive material, and to a material manufactured according to the same. The coating method according to the present invention fundamentally prevents the incorporation of heterogeneous impurities resulting from the addition of a separate adhesive material, thereby preventing a decrease in product purity and enabling the expression of the material's inherent insulating and thermal insulation capabilities. Furthermore, due to excellent interlayer bonding strength, performance degradation is suppressed even in environments exposed to high temperatures, flames, and high voltages, allowing it to be utilized as a composite material in various industrial fields.

Description

Technology Field

[0001] The present invention relates to the field of insulation and thermal insulation technology, and specifically to a multilayer coating method capable of producing a material with excellent insulation and thermal insulation capabilities by stably and directly coating a coating composition, an insulating material, or a thermal insulation material onto a target material without the addition of an adhesive material while maintaining high purity, and to a material produced thereby. Background Technology

[0003] As safety standards become more sophisticated across industries, the application of insulating or thermal insulation materials is becoming essential in various fields of application, such as electric vehicles, high-voltage battery packs (rechargeable batteries), industrial high-power equipment, aerospace, and advanced building materials, to protect components and equipment from high-temperature and high-voltage environments and prevent thermal runaway.

[0004] In order to impart such insulation or thermal insulation performance to the material, a process of laminating special-purpose insulating or thermal insulation materials, such as ceramics, silicone rubber, and flame-retardant polymers, onto the surface of a substrate (fabric or substrate) has been widely used in the past. However, due to the chemical properties of the above insulating and thermal insulation materials, the surface affinity and physical bonding strength with the fabric or substrate are significantly low, so there is a process limitation in that it is difficult to form a stable coating layer on the substrate and maintain an attached state using only lamination coating with an adhesive material (e.g., adhesive).

[0005] In other words, conventional technology required the lamination coating process to be performed by necessarily interposing a separate adhesive material, chemical adhesive, or adhesion-enhancing additive between the substrate and the insulating / thermal insulation material. However, when an adhesive material is included during lamination coating, chemical components heterogeneous to the inherent insulating and thermal insulation materials are incorporated into the coating layer as impurities, causing a severe reduction in the overall purity of the product.

[0006] Consequently, the inherent electrical and thermal resistance of the material is compromised by such incorporated adhesive impurities. When exposed to high voltage or high-temperature environments, the heat-vulnerable adhesive layer undergoes degradation first, or insulation breakdown occurs. This presents a critical problem that can ultimately cause delamination between the substrate and the coating layer, drastically reducing the material's overall insulation and thermal performance. Prior art literature

[0008] Republic of Korea Published Patent Application No. 10-2022-0041365 The problem to be solved

[0009] The present invention aims to overcome the limitations of conventional lamination coating processes, such as the incorporation of impurities due to the use of adhesive materials, the resulting decrease in product purity, and the consequent decrease in insulation and thermal insulation performance.

[0010] Specifically, the present invention aims to provide a coating method and a material having insulating or insulating ability manufactured therefrom, by providing a multilayer coating technology that can strongly bond an insulating or thermal insulation material without adding a separate adhesive material after applying a coating composition having a specific composition as a first step, thereby fundamentally blocking the intervention of impurities caused by adhesive materials and stably expressing the inherent insulating and thermal insulation performance of the material.

[0011] However, the problems that this invention seeks to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art from the description below. means of solving the problem

[0013] To achieve the above objectives, a coating method for manufacturing a material having insulating ability or thermal insulation ability according to one aspect of the present invention is,

[0014] (a) a step of preparing a first mixture comprising an inorganic binder component, a phosphorus-based flame retardant component, a surface modifier, a catalytic metal oxide, and a foam remover; (b) a step of preparing a second mixture comprising an organic binder component, ionized water, and a thickener; (c) a step of preparing a third mixture by mixing the first mixture and the second mixture; (d) a step of preparing a coating composition by adding a graphite-based filler to the third mixture; (e) a step of forming a first coating layer by coating one or both surfaces of a target material with the coating composition; and (f) a step of forming a second coating layer by coating one or more selected from the group consisting of the coating composition, an insulating material, and a thermal insulation material on the first coating layer without adding an adhesive material.

[0015] In one embodiment of the present invention, the coating composition may comprise, with respect to 100 parts by weight of the third mixture, 20 to 40 parts by weight of the inorganic binder component, 10 to 20 parts by weight of the phosphorus-based flame retardant component, 10 to 20 parts by weight of the surface modifier, 8 to 14 parts by weight of the catalytic metal oxide, 0.5 to 1.5 parts by weight of the foam remover, 20 to 30 parts by weight of the organic binder component, 1 to 3 parts by weight of the ionized water, 0.5 to 2 parts by weight of the thickener, and 5 to 20 parts by weight of the graphite-based filler.

[0016] The above catalytic metal oxide may include one or more selected from the group consisting of zinc oxide (ZnO), aluminum oxide (Al2O3), iron oxide (Fe2O3 or Fe3O4), zirconium oxide (ZrO2), tin oxide (SnO2), cerium oxide (CeO2), molybdenum oxide (MoO3), magnesium oxide (MgO), copper oxide (CuO or Cu2O), antimony oxide (Sb2O3), nickel oxide (NiO), tungsten oxide (WO3), and vanadium oxide (V2O5), and specifically may be titanium dioxide (TiO2).

[0017] In one embodiment of the present invention, if the inorganic binder component is included in an amount of less than 20 parts by weight, the bonding strength between the inorganic components may be reduced, which may lower the mechanical stability and durability of the coating layer; if it is included in an amount exceeding 40 parts by weight, the viscosity of the composition may increase excessively, which may lower dispersibility and applicability, and consequently, a problem may arise in which it is difficult to secure uniform insulation performance or thermal insulation performance.

[0018] In one embodiment of the present invention, if the phosphorus-based flame retardant component is included in an amount of less than 10 parts by weight, the supply of phosphorus-based components required for the flame retardant reaction is insufficient, so flame retardant performance and thermal insulation performance may not be sufficiently expressed, and if it is included in an amount exceeding 20 parts by weight, the proportion of inorganic components in the composition increases excessively, resulting in reduced dispersibility and reduced uniformity and mechanical stability of the coating layer.

[0019] In one embodiment of the present invention, if the surface modifier is included in an amount of less than 10 parts by weight, the interfacial bonding force between the inorganic component and the flame retardant component and the binder is not sufficiently secured, so dispersion stability and coating uniformity may be reduced, and if it is included in an amount exceeding 20 parts by weight, the viscosity and fluidity of the composition change due to the excessive presence of the surface modifier, so coating stability and mechanical properties may be reduced.

[0020] In one embodiment of the present invention, if the organic binder component is included in an amount of less than 20 parts by weight, the inorganic binder component and the phosphorus-based flame retardant component are not sufficiently bonded and fixed, which may result in reduced adhesion and mechanical stability of the coating layer; and if it is included in an amount exceeding 30 parts by weight, the thermal insulation performance may be reduced or shape stability may be reduced upon exposure to high temperatures as the proportion of the organic binder component becomes excessive.

[0021] In one embodiment of the present invention, the step (g) may further include the step of additionally coating one or more selected from the group consisting of the coating composition, insulating material, and thermal insulation material on the second coating layer to form a total coating layer of 3 to 4 layers, thereby providing a critical increase effect in insulating ability or thermal insulation ability due to the multilayer interface structure.

[0023] Another aspect of the present invention provides a material having insulating or thermal insulation ability manufactured according to the above method, wherein the material comprises one or more selected from the group consisting of films, sheets, pads, and refractory composites. Effects of the invention

[0025] The coating method and material according to embodiments of the present invention provide the following excellent effects.

[0026] First, since no adhesive materials or separate chemical adhesives are used at all during the lamination coating process of insulating or thermal insulation materials, the deterioration of product purity due to the incorporation of foreign substances can be fundamentally prevented. Consequently, the pure electrical and thermal resistance of the material itself is preserved, enabling the expression of excellent insulation or thermal insulation performance.

[0027] Second, since the first coating layer acts as a strong self-binder (anchor) between the target material and the insulating / thermal insulation material, interlayer delamination is suppressed even in high-temperature exposure or physical stress environments, and the long-term durability of the coating layer can be significantly improved.

[0028] Third, by providing process stability that allows the coating composition and heterogeneous insulating / thermal insulation materials to be continuously laminated into a multi-layer structure of 2, 3, or 4 or more layers without the addition of adhesive materials, it is possible to create synergistic effects of insulation performance, thermal insulation performance, and structural stability through the formation of a complex layered structure. Brief explanation of the drawing

[0030] FIG. 1 is an optical microscope image showing the shape and distribution according to particle size (S: average about 150 μm, M: average about 250 μm, L: average about 500 μm) of fine particulate graphite according to one embodiment of the present invention. FIG. 2a is an image showing fire resistance and thermal insulation testing equipment according to one embodiment of the present invention, and FIG. 2b is an image showing the state in which fire resistance and thermal insulation testing is performed according to one embodiment of the present invention. FIG. 3 is a temperature graph showing the change in front temperature and back temperature according to the flame exposure time during fire resistance and thermal insulation tests for a sample to which the coating composition of Example 3 of the present invention is applied to a standard fabric (#118, XTBS180 glass fabric fiber). FIG. 4 is a temperature graph showing the change in front temperature and back temperature according to the flame exposure time during fire resistance and thermal insulation tests for a sample to which the coating composition of Example 3 of the present invention is applied to an ultra-thin, highly flexible glass fabric fiber (#7628). FIG. 5 is a temperature graph showing the change in front temperature and rear temperature according to the flame exposure time during fire resistance and thermal insulation tests for a sample with a two-layer laminated structure applied according to Example 12 of the present invention. FIG. 6 is a temperature graph showing the change in front temperature and rear temperature according to the flame exposure time during fire resistance and thermal insulation tests for a sample with a three-layer laminated structure applied according to Example 13 of the present invention. FIG. 7 is a temperature graph showing the change in front temperature and rear temperature according to the flame exposure time during fire resistance and thermal insulation tests for a sample with a three-layer laminated structure and adhesive components applied according to Comparative Example 18 of the present invention. FIG. 8 is a temperature graph showing the change in front temperature and rear temperature according to the flame exposure time during fire resistance and thermal insulation tests for a sample with a four-layer laminated structure applied according to Example 19 of the present invention. FIG. 9 is a temperature graph showing the change in front temperature and rear temperature according to the flame exposure time during fire resistance and thermal insulation tests for a sample with a 4-layer laminated structure and adhesive components applied according to Comparative Example 21 of the present invention. FIG. 10 is an image showing a material coated on one side with a two-layer laminated structure and a material coated on both sides with a two-layer laminated structure according to Examples 10 and 11 of the present invention. Specific details for implementing the invention

[0031] Specific structural or functional descriptions of the embodiments are disclosed for illustrative purposes only and may be modified and implemented in various forms. Accordingly, the embodiments are not limited to the specific disclosed forms, and the scope of this specification includes modifications, equivalents, or substitutions that fall within the technical concept.

[0032] Terms such as first or second may be used to describe various components, but these terms should be interpreted solely for the purpose of distinguishing one component from another. For example, the first component may be named the second component, and similarly, the second component may also be named the first component.

[0033] When it is stated that a component is "connected" to another component, it should be understood that it may be directly connected to or joined to that other component, or that there may be other components in between.

[0034] The terms used in the embodiments are for illustrative purposes only and should not be interpreted as intended to be limiting. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "comprising" or "having" are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0035] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the embodiments pertain. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0036] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described in detail below. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0037] In the embodiments of the present invention, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in the embodiments of the present invention.

[0038] Furthermore, in describing the present invention, if it is determined that a detailed description of related prior art could unnecessarily obscure the essence of the present invention, such detailed description is omitted. Where terms such as "includes," "has," or "is made up" are used in this specification, other parts may be added unless "only" is used. Where a component is expressed in the singular, it includes cases where it is included in the plural unless specifically stated otherwise.

[0039] In interpreting the components, they are interpreted to include a margin of error even in the absence of a separate explicit statement.

[0040] The features of each of the various embodiments of the present invention may be combined or combined with one another, either partially or wholly, and as will be fully understood by those skilled in the art, various technical interlocking and operation are possible, and each embodiment may be implemented independently of one another or together in an interlocking relationship.

[0042] Embodiments of the present invention have been described in detail below, but the present invention is not limited thereto.

[0044] The first aspect of the present invention provides a coating method for manufacturing a material having insulating ability or thermal insulation ability, comprising: (a) preparing a first mixture comprising an inorganic binder component, a phosphorus-based flame retardant component, a surface modifier, a catalytic metal oxide, and a foaming agent; (b) preparing a second mixture comprising an organic binder component, ionized water, and a thickening agent; (c) preparing a third mixture by mixing the first mixture and the second mixture; (d) preparing a coating composition by adding a graphite-based filler to the third mixture; (e) forming a first coating layer by coating one or both surfaces of a target material with the composition; and (f) forming a second coating layer by coating one or more selected from the group consisting of the coating composition, an insulating material, and a thermal insulation material without adding an adhesive material onto the first coating layer.

[0045] In one embodiment of the present invention, the first mixture and the second mixture may be manufactured separately, taking into account different component combinations and functional roles. Specifically, the first mixture is intended to ensure interfacial affinity between an inorganic binder component and a flame-retardant / functional inorganic component, and the second mixture is intended to control the viscosity of the coating solution and the adhesion to the target material through an organic binder component. Since local aggregation may occur if mixed in a single step, the first mixture and the second mixture are manufactured separately and then mixed to achieve the coating stability and high-purity surface quality of the coating composition.

[0046] In one embodiment of the present invention, the inorganic binder component can play a role in stably binding the phosphorus-based flame retardant component and the inorganic filler and ensuring the mechanical stability of the coating layer, and the phosphorus-based flame retardant component can act as a key component that exhibits flame retardant and thermal insulation performance by inducing the formation of a carbonized layer and a phosphorus-based flame retardant reaction upon exposure to high temperatures. In addition, the surface modifier can play a role in improving the dispersion stability and coating uniformity of the composition by enhancing the interfacial affinity between the inorganic binder component, the phosphorus-based flame retardant component, and other inorganic components. The organic binder component can fix the inorganic component to the surface or interior of the substrate and provide adhesion and flexibility to the coating layer, and the ionized water can contribute to maintaining dispersion stability during long-term storage by minimizing interference between ions within the composition. The thickener can play a role in improving the uniformity of coating thickness and process reproducibility during the coating process by controlling the viscosity of the composition and simultaneously suppressing the sedimentation of the inorganic component and the flame retardant component. In addition, the catalytic metal oxide can act as an inorganic filler to assist in the heat insulation effect upon exposure to high temperatures, while simultaneously maintaining the color stability and surface quality of the coating layer. The foaming agent can suppress bubbles generated during the mixing and stirring process, thereby improving the dispersion stability of the composition and the reproducibility of the coating process.

[0047] In one embodiment of the present invention, a styrene-acrylic copolymer aqueous emulsion with excellent handling properties in terms of mixing stability with inorganic components and forming a coating layer may be used as the inorganic binder component. In addition, the phosphorus-based flame retardant component may include one or more selected from the group consisting of melamine phosphate, melamine pyrophosphate, melamine polyphosphate, aluminum phosphate, magnesium phosphate, calcium phosphate, guanidine phosphate, triphenyl phosphate, tricresyl phosphate, resorcinol bis(diphenyl phosphate), and bisphenol A bis(diphenyl phosphate), which can induce the formation of a carbonized layer through a phosphorus-based flame retardant reaction upon exposure to high temperature, and specifically, may be ammonium polyphosphate. An acrylic aqueous resin solution may be used to stably fix inorganic components and flame-retardant components to the surface or interior of the substrate using the above organic binder component, and to ensure the adhesion and flexibility of the coating layer.

[0048] The graphite-based filler described above can contribute to the continuous manifestation of flame retardant and thermal insulation performance by providing a heat blocking effect and a heat diffusion inhibition effect based on a layered structure upon exposure to high temperatures, while simultaneously reinforcing the structural stability of the carbonized layer formed by phosphorus-based flame retardant components. In addition, the graphite-based filler can provide excellent thermal insulation performance by complicating the heat transfer path through anisotropy in the direction of heat conduction and a peeled layered structure, thereby effectively delaying the transfer of heat from flames or high temperatures to the rear.

[0049] If the graphite-based filler is included in an amount of less than 5 parts by weight, the effect of improving thermal insulation performance is not sufficiently manifested, and the basic flame retardant and thermal insulation performance levels resulting from the inorganic binder component and the phosphorus-based flame retardant component may remain. On the other hand, if the graphite-based filler is included in an amount exceeding 20 parts by weight, the dispersion stability and coating uniformity of the composition may be reduced, or the mechanical stability and process reproducibility of the coating layer may be reduced.

[0050] In one embodiment of the present invention, the graphite-based filler may include particulate graphite (expandable graphite, EG), graphene nanoplates, or super graphite.

[0051] In one embodiment of the present invention, the particle diameter of the fine graphite is 10 μm to 250 μm, the thickness of the graphene nanoplate is 50 nm to 100 nm, and the particle diameter of the super graphite may be 1 μm or less. If the particle diameter of the fine graphite exceeds 250 μm, dispersibility within the composition may be reduced, making it difficult to achieve uniform mixing with the inorganic binder component and the phosphorus-based flame retardant component, and consequently, flame retardant and thermal insulation performance may be locally and unevenly expressed within the coating layer. Furthermore, if the particle size is excessively large, there is a risk that the coating stability and surface quality of the composition may be reduced, or that process reproducibility may be reduced.

[0052] Specifically, the particle diameter of the fine particulate graphite may be 10 µm to 200 µm, 10 µm to 150 µm, 30 µm to 250 µm, 30 µm to 200 µm, 30 µm to 150 µm, 50 µm to 250 µm, 50 µm to 200 µm, 50 µm to 150 µm, 100 µm to 250 µm, 100 µm to 200 µm, 100 µm to 150 µm, 120 µm to 250 µm, 120 µm to 200 µm, and 120 µm to 150 µm.

[0053] In one embodiment of the present invention, the first mixture and the second mixture may be manufactured separately, taking into account different component combinations and functional roles. Specifically, the first mixture is intended to primarily secure dispersion stability and interfacial bonding strength between the inorganic and flame-retardant components by including an inorganic binder component, a phosphorus-based flame-retardant component, a surface modifier, a catalytic metal oxide, and a foaming agent, while the second mixture is intended to precisely control the viscosity, fluidity, and applicability of the composition by including an organic binder component, ionized water, and a thickener. If these components are mixed simultaneously in a single mixing step, local aggregation of the phosphorus-based flame-retardant component or the inorganic component, abrupt changes in viscosity, or non-uniform dispersion may occur, which may lead to a decrease in the applicability and reproducibility of the thermal insulation performance of the composition. Accordingly, by preparing the first mixture and the second mixture separately and then mixing them to produce a third mixture, the dispersion stability of the inorganic component and the applicability and adhesion strength provided by the organic component can be simultaneously and stably secured.

[0054] In one embodiment of the present invention, the inorganic binder component, the phosphorus-based flame retardant component, and the graphite-based filler do not function independently of each other, but interact upon exposure to high temperature or high voltage to produce a combined thermal insulation or insulating effect. Specifically, the carbonized layer formed by the phosphorus-based flame retardant component is structurally reinforced by the layered structure of the graphite-based filler, and the inorganic binder component stably supports the carbonized layer and the filler structure, thereby allowing the thermal insulation or insulating performance to be maintained for a long time even under high temperature or high voltage conditions.

[0055] A coating composition according to one embodiment of the present invention may be applied to fabrics, fibers, films, sheets, or substrates, and gravure coating, comma coating, or squeegee coating may be used as the application method.

[0056] The above gravure coating can be performed using a direct gravure method or a micro gravure method. The direct gravure method transfers the coating liquid through contact between a backup roll and a gravure roll, making it suitable for high-speed production. The micro gravure method allows for more uniform and precise application of the coating liquid by minimizing the contact area between the substrate and the coating roll through the miniaturization of the roll radius. Additionally, comma coating allows for precise control of the coating thickness by adjusting the gap between the comma roll and the substrate, while squeegee coating allows for thin and uniform application of the coating liquid to the substrate using a squeegee, while simultaneously improving penetration into the substrate.

[0057] In one embodiment of the present invention, the insulating material or thermal insulation material may refer to a material known and commercially available in the art, and specifically may be ceramic silicone rubber or flame-retardant rubber, rubber with added flame-retardant filler, etc., but is not limited thereto.

[0058] In one embodiment of the present invention, the step (f) is performed using the chemical activity and self-bonding force on the first coating layer, and by excluding the intervention of adhesive substances (impurities), it may be a key step that can fully express the inherent physical and chemical performance values ​​of the insulating material or thermal insulation material as the physical properties of the final product.

[0059] In one embodiment of the present invention, the coating method may further include the step of (g) additionally coating one or more selected from the group consisting of the coating composition, insulating material and thermal insulation material on the second coating layer to form a total coating layer of 3 to 4 layers, thereby providing a critical increase effect in insulating ability or thermal insulation ability due to the multilayer interface structure.

[0060] According to one embodiment of the present invention, regarding a material having a laminated structure of three to four layers formed by applying a first coating layer containing the coating composition, a second coating layer containing the coating composition, an insulating material or a thermal insulation material, and an additional coating layer, it was confirmed that excellent thermal insulation performance (thermal insulation of approximately 741°C) was achieved during fire resistance and thermal insulation tests, and that excellent thermal insulation performance (insulation breakdown voltage of 42.0 kV / mm) was also achieved during insulation tests. On the other hand, it was confirmed that when an adhesive material is added between the coating layers, the thermal insulation performance is reduced, and the thermal insulation performance is also significantly reduced due to impurities.

[0061] In one embodiment of the present invention, the thickness of the material having the insulating or thermal insulation ability may be 0.3 mm or more and 2.0 mm or less, but is not limited thereto.

[0062] The coating method according to the present invention comprises forming a first coating layer by coating a coating composition on a target material, and forming a second coating layer by coating at least one of the coating composition, an insulating material, or a thermal insulation material on the first coating layer. Thus, the material of the present invention essentially comprises two or more layers of multiple coating layers (a first coating layer and a second coating layer), thereby enabling significantly improved insulation or thermal insulation capabilities compared to the prior art.

[0063] Accordingly, the thickness of the material may be 0.3 mm or more in order to fully realize the excellent insulation or thermal insulation ability exhibited by the above coating layers to the intended level. If the thickness of the material is less than 0.3 mm, the two or more coating layers that are essential components cannot be formed with sufficient thickness and density, and thus cannot effectively block external heat or current, there is a possibility that a problem may arise in which the insulation or thermal insulation ability cannot be effectively exhibited.

[0064] In addition, the upper limit of the thickness of the above material is not specifically restricted, and it will be obvious to those skilled in the art that the thickness can be appropriately adjusted within a range of 0.3 mm or more according to the specific industrial field to which the material according to the present invention is to be applied (e.g., exterior building materials, internal components of electronic devices, battery insulation materials, etc.) and the specifications and required physical properties of the final product to be applied.

[0065] For example, depending on the specifications of the product to be applied and the required physical properties, the thickness of the material may be 0.3 mm to 2 mm, 0.3 mm to 1.9 mm, 0.3 mm to 1.8 mm, 0.3 mm to 1.7 mm, 0.3 mm to 1.6 mm, and 0.3 mm to 1.5 mm.

[0067] A second aspect of the present invention provides a material having insulating or thermal insulation ability manufactured according to a coating method according to the first aspect of the present invention, wherein the material comprises one or more selected from the group consisting of films, sheets, pads, and refractory composites.

[0068] In one embodiment of the present invention, the manufactured material has a multi-layer coating structure excluding adhesive materials, thereby suppressing deterioration, cracking, and peeling of the coating layer even in harsh environments exposed to high temperatures, flames, or high-voltage heat sources, and accordingly, it can be effectively utilized in industries requiring high safety, such as power cables, secondary battery protective members, and industrial thermal insulation fibers.

[0070] Hereinafter, the structure of the present invention and the resulting effects are to be explained in more detail through specific embodiments and comparative examples. However, these embodiments are intended to explain the present invention more specifically, and the scope of the present invention is not limited to these embodiments.

[0072] Preparation Example 1: Preparation of a coating composition for coating a material having insulating ability or insulating ability

[0073] [Table 1]

[0074]

[0076] 1-1. Preparation of the First Mixture

[0077] 18 g of a phosphate-based flame retardant component was added to and mixed with 36 g of a styrene-acrylic copolymer aqueous emulsion as an inorganic binder component. Subsequently, 11 g of a silicone-based coupling agent was added as a surface modifier to improve the dispersibility and interfacial bonding strength of the inorganic binder component and the phosphate-based flame retardant component. Afterward, 10 g of a catalytic metal oxide was added to reinforce flame retardant performance and provide color stability, and 1 g of a defoaming agent was added to suppress bubbles that may occur during the stirring process. After mixing the above components, a first mixture was prepared by uniformly stirring using a stirrer for at least one hour.

[0078] 1-2. Preparation of the Second Mixture

[0079] 2 g of deionized water was added to 21 g of an acrylic aqueous resin solution as an organic binder component to control viscosity and stabilize the composition. Subsequently, 1 g of hydroxyethyl cellulose (HEC) was added as a thickening agent to control the viscosity of the composition. The above components were mixed for more than 1 hour under low-speed stirring conditions to prepare a second mixture with uniformly controlled viscosity.

[0080] 1-3. Preparation of the Third Mixture

[0081] A third mixture (Example 1) was prepared by slowly adding a second mixture to the first mixture prepared above while continuing to stir, in which the inorganic and organic components were uniformly dispersed.

[0082] 1-4. Preparation of coating composition

[0083] [Table 2]

[0084]

[0085] Examples 2 to 9 were prepared by additionally adding fine graphite to the third mixture (Example 1) prepared above. The fine graphite was prepared through a stripping and fine grinding process using a ball mill, and was used with S (average 150 μm) and M (average 250 μm) depending on the average particle diameter (see FIG. 1), and was prepared by additionally adding 5 g, 10 g, 15 g, and 20 g to 100 g of the third mixture.

[0086] 1-5. Preparation of Comparative Examples 1 to 15

[0087] [Table 3]

[0088]

[0089] Comparative Examples 1 to 8 were prepared by adding an inorganic binder, a flame retardant, a surface modifier, and an organic binder, respectively, in excess or in insufficient amounts, according to Table 3 above.

[0090] [Table 4]

[0091]

[0092] Comparative Examples 9 to 12 were prepared by additionally adding 2 g and 25 g of fine particulate graphite (S and M), respectively, based on 100 g of the third mixture, to the composition of the third mixture (Example 1), and Comparative Examples 13 to 15 were prepared by additionally adding 2 g, 5 g, and 10 g of fine particulate graphite (see FIG. 1), with an average particle diameter of L (500 μm), respectively, based on 100 g of the third mixture, to the composition of the third mixture (Example 1).

[0094] Experimental Example 1: Evaluation of Fire Resistance and Thermal Insulation Performance

[0095] 1-1. Experimental Method

[0096] Fire resistance and thermal insulation performance were evaluated for the examples and comparative examples prepared according to Manufacturing Example 1 above. The fire resistance and thermal insulation tests were performed using XCM FRT 1.0 fire resistance test equipment, which is capable of applying a flame of approximately 900°C to 1,000°C under direct flame conditions without time limit (see Fig. 2a).

[0097] Specifically, after attaching the sample to the SUS plate, thermocouples were installed on the front side, which is directly exposed to the flame, and on the rear side, which is not exposed, respectively, to measure the changes in front and rear temperatures in real time over time of flame exposure. A reference fabric (#118, XTBS180 glass fabric fiber) was used.

[0098] The above coating composition was applied to existing fabrics using a microgravure coating method. The samples coated with the composition were subsequently dried to produce test specimens, and the thickness of the test specimens was adjusted to be within the range of 0.2 mm to 0.3 mm depending on the process conditions and the type of fabric. Fire resistance and thermal insulation performance evaluations were performed based on the following criteria: average front temperature (°C), average back temperature (°C), and thermal insulation (temperature difference between the front and back temperatures, °C).

[0099] 1-2. Experimental Results

[0100] 1-2-1. Examples and Comparative Examples

[0101] [Table 5]

[0102]

[0103] As can be seen in Table 5 above, the average front temperature in Examples 1 to 9 was stably maintained at around 900°C, and in Examples 2 to 9, the average back temperature was further reduced (at least 240°C), confirming that the thermal insulation performance was significantly improved. In particular, it was confirmed that Example 3, which applied 10% EG (S, average 150 μm), had the best thermal insulation characteristics (thermal insulation performance of 665°C).

[0104] On the other hand, Comparative Examples 1 to 8 had generally high average rear temperatures (at least 370°C), so their thermal insulation performance was limited, and it was confirmed that Comparative Examples 9 to 15 also had limited improvement in thermal insulation performance.

[0105] 1-2-2. Fabric extension verification for Example 3

[0106] [Table 6]

[0107]

[0108] As a result of conducting tests by applying the same condition of EG (S, average 150 μm) 10% (Example 3), which is the condition with the best thermal insulation performance in the results of Experimental Example 1-2-1 above, and changing the fabric type to XTBS-220, ultra-thin high-flexibility glass fabric fiber (#7628), silane-treated ultra-thin high-flexibility glass fabric fiber, and glass fabric fiber (Beihai fabric), it was confirmed that even with different fabrics, the average front temperature was maintained at around 900℃ while the average back temperature was controlled to be low, thereby stably securing thermal insulation performance, and overall, a tendency was observed to maintain thermal insulation performance of 630℃ or higher.

[0110] Experimental Example 2: Insulation Performance Evaluation

[0111] 2-1. Experimental Method

[0112] The insulation performance of the examples and comparative examples prepared according to Manufacturing Example 1 above was evaluated. The thermal insulation test was performed by measuring the dielectric breakdown voltage according to ASTM D149.

[0113] Specifically, the sample was prepared in the same manner as in Experimental Example 1-1 above, the sample was placed between two electrodes at room temperature (approx. 25°C), and the voltage was increased at a constant rate of 500V per second, and the voltage at the point where current flows through the sample, i.e., when the thermal conductivity is destroyed, was measured. The measured voltage was divided by the average thickness (0.25 mm) of the sample to calculate the dielectric breakdown voltage per unit thickness (kV / mm).

[0114] 2-2. Experimental Results

[0115] [Table 7]

[0116]

[0117] As can be seen in Table 7 above, Examples 2 to 9 were found to have excellent insulation properties, with dielectric breakdown voltages measured to be between 13.5 kV / mm and 18.5 kV / mm. In particular, Example 3, which used 10% EG (S, average 150 μm), was found to have the best insulation characteristics (dielectric breakdown voltage of 18.5 kV / mm).

[0118] On the other hand, Comparative Examples 1 to 8 were found to have dielectric breakdown voltages of 8.2 kV / mm to 9.1 kV / mm, indicating that they do not function as insulating materials. Additionally, Comparative Examples 9 to 15 were found to have dielectric breakdown voltages of 9.6 kV / mm to 10.8 kV / mm, which is slightly higher than Comparative Examples 1 to 8, but significantly inferior in insulation performance compared to Examples 2 to 9.

[0119] The above results suggest that the combination ratio of organic binder components and inorganic binder components optimized according to the present invention plays the most important role as the basis for forming an insulating film, and that a synergistic effect of thermal insulation performance and insulating performance can be achieved only when a graphite filler with a specific range of particle sizes is applied within a specific range (5% to 20%) on that basis.

[0121] Experimental Example 3: Evaluation of Adhesion Strength and Process Stability Depending on the Addition of Adhesive

[0122] 3-1. Experimental Method

[0123] In order to determine whether the coating method according to the present invention can overcome the process limitations in which the use of an adhesive is unavoidable in the conventional process of coating insulating or thermal insulation materials onto a material, the adhesive strength and process stability according to the addition of an adhesive were evaluated as follows.

[0124] Ceramic silicone rubber (hereinafter CSR) or flame-retardant rubber (hereinafter RT) was applied directly to the surface of a pure standard fabric with no coating layer applied and a fabric with a first coating layer applied (condition of Example 3, hereinafter SP), respectively, without an adhesive and dried.

[0125] Subsequently, to objectively evaluate the adhesion of the applied layer, an adhesion test was performed according to the ASTM D3359 (Cross-cut tape test) standard. A grid of 100 lines was created on the surface of the specimen by drawing 11 horizontal and 11 vertical lines at 1 mm intervals using a knife. A standard adhesive tape was then firmly applied over the grid and quickly peeled off at a 180-degree angle. After peeling off the tape, the area where the coating layer had peeled off was calculated, and the adhesion strength was determined as a score ranging from 0B (more than 65% peeling) to 5B (0% peeling, perfect adhesion).

[0126] 3-2. Experimental Results

[0127] [Table 8]

[0128]

[0129] As can be seen in Table 8 above, in Comparative Example 16, in which no adhesive or other additives were used without the first coating layer (condition of Example 3) being applied, the coating layer (CSR) was found to be floating on the surface of the fabric and completely detached upon tape adhesion, and in Comparative Example 17, it was confirmed that the coating layer (RT) crumbled due to physical friction after drying, resulting in a complete failure to bond with the fabric (0B to 1B) due to the low surface tension characteristic of ceramic silicone rubber (CSR) or flame-retardant rubber (RT) materials. Therefore, it can be seen that the reason why adhesives or other additives were essential in the prior art has been proven by experimental data.

[0130] On the other hand, Example 10, in which the first coating layer was formed with the coating composition (SP) of the present invention, achieved perfect integration without any detachment of the interface, and Example 11 confirmed that the original shape of the coating layer (RT) was maintained even under strong bending or tape detachment, and was measured as the highest grade 5B, meaning a peel rate of 0%, even though ceramic silicone rubber (CSR) or flame-retardant rubber (RT), which correspond to heterogeneous materials, were applied without an adhesive.

[0131] Through the above results, it was confirmed that the first coating layer according to the present invention not only exhibits insulation and thermal insulation capabilities, but also acts as a 'strong anchor' that chemically and physically strongly connects the lower fabric and the upper special insulation or thermal insulation material. Therefore, the coating method according to the present invention suggests that it has an overwhelming process and physical property advantage over conventional technology in that it can stably implement a heterogeneous material coating process without the addition of an impurity called an adhesive.

[0133] Preparation Example 2: Preparation of a material having a multilayer laminated structure by applying an additional coating with a coating composition, an insulating material, or a thermal insulation material.

[0134] In order to confirm the effect of improving thermal insulation and insulation performance due to the additional lamination of an insulating material or insulating material in addition to the coating composition according to the present invention, a sample was prepared by coating an existing fabric with the coating composition under the conditions of Example 3 (first coating layer) as in Experimental Example 1-1 above, and a sample was prepared by additionally coating (second coating layer) the coating composition under the same conditions of Example 3 (hereinafter, SP), ceramic silicone rubber (CSR), or flame-retardant rubber (RT) thereon. Subsequently, a sample was prepared by additionally coating the coating composition under the conditions of Example 3, ceramic silicone rubber (CSR), or flame-retardant rubber (RT) on the second coating layer so that the total coating layer is 3 to 4 layers.

[0135] In addition, to confirm the structural excellence and thermal insulation effect of the material according to the adhesive-free coating method of the present invention, a sample was prepared in which a conventionally commercialized acrylic heat-resistant adhesive was added to a thickness of 0.05 mm between ceramic silicone rubber coating layers or between flame-retardant rubber coating layers.

[0136] [Table 9]

[0137]

[0139] Experimental Example 4: Evaluation of Thermal Insulation Performance of a Material with a Multilayered Structure

[0140] 4-1. Experimental Method

[0141] Similar to Experimental Example 1-1 above, fire resistance and thermal insulation performance were evaluated for the examples and comparative examples prepared according to Manufacturing Example 2 above.

[0142] 4-2. Experimental Results

[0143] [Table 10]

[0144]

[0145] As can be seen in Table 10 above, in Examples 10 to 20, the average front temperature was stably maintained at around 900°C, and it was confirmed that the average back temperature was further reduced, significantly improving thermal insulation (maximum 741°C, Example 19). On the other hand, it was confirmed that Comparative Examples 18 to 21 did not exhibit excellent thermal insulation as well as the examples having the same coating layer composition.

[0146] In particular, in Example 16 and Comparative Example 18, even though the same insulating material (CSR) was coated with the same number of layers, a significant difference in thermal insulation performance occurred depending on the presence or absence of an adhesive, and it was confirmed that the adhesive added between the layers deteriorated and peeled off severely when exposed to high temperatures, making it undesirable for application to materials requiring excellent thermal insulation performance.

[0148] Experimental Example 5: Evaluation of heat transfer performance of a material having a multilayered structure

[0149] 5-1. Experimental Method

[0150] Similar to Experimental Example 2-1 above, heat transfer performance was evaluated for the examples and comparative examples prepared according to Manufacturing Example 2 above.

[0151] 5-2. Experimental Results

[0152] [Table 11]

[0153]

[0154] As can be seen in Table 11 above, Examples 10 to 20 showed a tendency for improved insulation performance as a coating layer was added, and in particular, Example 18 was found to have the best insulation characteristics (dielectric breakdown voltage 42.0 kV / mm). On the other hand, Comparative Examples 18 to 21 were found to have lower insulation performance compared to the Examples despite the addition of a coating layer.

[0156] The results of the above experimental example suggest that when a target material is coated according to the coating method of the present invention, thermal insulation performance and insulation performance can be improved while maintaining structural stability even if a coating layer is added, and thus it can be effectively applied by appropriately adjusting the thickness and number of layers according to the industrial field and the product to be used.

[0158] The various embodiments described above may be embodied in other specific forms without departing from the technical idea and essential features. Accordingly, the above detailed description should not be interpreted restrictively in all respects but should be considered exemplary. The scope of the various embodiments shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the various embodiments are included within the scope of the various embodiments. Furthermore, embodiments may be constructed by combining claims that do not have an explicit citation relationship in the patent claims, or they may be included as new claims through amendments made after filing.

Claims

Claim 1 (a) a step of preparing a first mixture comprising an inorganic binder component, a phosphorus-based flame retardant component, a surface modifier, a catalytic metal oxide, and a defoaming agent; (b) a step of preparing a second mixture comprising an organic binder component, ionized water, and a thickener; (c) a step of preparing a third mixture by stirring the first mixture and the second mixture; (d) a step of preparing a coating composition by adding a graphite-based filler to the third mixture; (e) a step of forming a first coating layer by coating one or both surfaces of a target material with the coating composition; A coating method for manufacturing a material having insulating ability or thermal insulation ability, comprising: (f) forming a second coating layer by coating one or more selected from the group consisting of the coating composition, insulating material, and thermal insulation material on the first coating layer without adding an adhesive material, wherein the coating composition comprises, with respect to 100 parts by weight of the third mixture, 20 to 40 parts by weight of the inorganic binder component, 10 to 20 parts by weight of the phosphorus-based flame retardant component, 10 to 20 parts by weight of the surface modifier, 8 to 14 parts by weight of the catalytic metal oxide, 0.5 to 1.5 parts by weight of the defoaming agent, 20 to 30 parts by weight of the organic binder component, 1 to 3 parts by weight of the ionized water, 0.5 to 2 parts by weight of the thickener, and 5 to 20 parts by weight of the graphite-based filler. method. Claim 2 delete Claim 3 A method according to claim 1, further comprising the step of (g) additionally coating one or more selected from the group consisting of the coating composition, insulating material and thermal insulation material on the second coating layer to laminate the entire coating layer to have three or four layers. Claim 4 A method according to claim 1 or 3, wherein the thickness of the material having the insulating ability or thermal insulation ability is 0.3 mm or more and 2.0 mm or less. Claim 5 A material having insulating ability or thermal insulation ability manufactured according to the method according to claim 1 or 3, wherein the target material comprises one or more selected from the group consisting of films, sheets, pads, and refractory composites.

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