Antiviral composite resin composition excellent in virus inactivation function and composite resin-coated steel sheet using the same

Abstract

The present invention contains 30 to 60% by weight of a urethane-modified polyester binder resin; 3 to 15% by weight of a curing agent; 0.1 to 10% by weight of a pigment; 0.1 to 10% by weight of an antiviral compound; and the balance solvent. The antiviral compound includes one or more selected from the group consisting of (A) metal hydroxides ([M1(OH)2]), (B) hydroxyapatite ([Ca 10 (PO4)6(OH)2]), and (C) thermosensitive titanium dioxide photocatalyst doped with metal ([M2-TiO2]). M1 is Ca or Mg, and M2 is Pt, Cr, V, Mn, Fe, Zn, Cu, Ni, Zr, Mo, Ag, W, or Au. The present invention provides an antiviral composite resin composition.

Description

Technical Field

[0001] The present invention relates to a composite resin composition having antiviral properties capable of killing viruses such as the coronavirus, and further to a composite resin-coated steel sheet having excellent virus-killing function using this composition.

Background Art

[0002] Recently, the worldwide pandemic of the coronavirus (Covid-19) has not only caused serious socio-economic problems but also an urgent situation for the development of vaccines and therapeutic agents. The coronavirus, which has been spreading worldwide recently, has evolved from the SARS in 2013, the MERS in 2016, and the Covid-19 virus in 2019. In addition, Covid-19 has mutated from alpha, beta, gamma, delta to the recently prevalent omicron, having a fatal impact on human health and healthcare. The coronavirus contains RNA nucleic acid in an outer shell composed of spherical lipids and proteins. Most viruses penetrate into human or animal host cells and proliferate by replicating nucleic acid in large quantities using the ribosomes of the host cells. Viruses are smaller in size compared to bacteria and fungi, can be propagated and replicated in a short time, have a high mutation rate, and have a large transmission power, making it difficult to develop therapeutic agents and vaccines.

[0003] On the one hand, it has been reported that copper metal surfaces, nano metals or metal ions, and quaternary ammonium ions have a killing function against viruses. It has been reported that copper metal kills bacteria or viruses by allowing nano metals eluted from the surface to penetrate into the outer skin of the bacteria or viruses, causing them to lose their replication function. Metal ions such as Ag, Ni, and Zn have also been reported to kill by a similar mechanism. Polymers containing quaternary ammonium are reported to kill by binding their inherent hydrophobic functional groups to the outer skin of bacteria or viruses and destroying their function. However, such metal ions are difficult to elute sufficient ions when used in coatings, or tend to have their effects reduced or disappear due to oxidation and discoloration during long-term use. In addition, the killing effect of organic compounds is not only incomplete when treating the surface of materials, but also has problems with human toxicity, so their use is restricted.

[0004] In particular, composite coating steel sheets used for household appliances and building materials are usually manufactured with a coating thickness of several to dozens of μm or more for long-term use of 10 years or more. In the case of the above metals, when a liquid coating solution is coated on the steel sheet, there is a high possibility of existing inside the coating film depending on the density, and there is a problem that it is difficult to exhibit functionality on the surface. In addition, there is a problem that the surface hue changes due to oxidation like copper metal during long-term use. Also, when using quaternary ammonium, although some effects appear, the immediate effect is insufficient and not complete, so there are limitations in its use.

[0005] As part of the efforts to solve such a harmful environment caused by viruses, there is a demand for the development of special surface treatment products that can impart an inactivation function against viruses, especially the novel coronavirus, to the surface of steel sheets, which are essential materials in our lives.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] One object of the present invention is, in order to solve the above problems, to use an inorganic compound that not only does not cause a change in hue even during long-term use but also has a lower density than metal particles and easily floats on the surface of the coating film, and to provide a coating composition having a function of killing microorganisms on the coating film surface.

[0008] Another object of the present invention is to provide a coated steel sheet using the coating composition having the above-described antiviral properties.

Means for Solving the Problems

[0009] According to one embodiment of the present invention, it contains 30 to 60% by weight of a urethane-modified polyester binder resin; 3 to 15% by weight of a curing agent; 0.1 to 10% by weight of a pigment; 0.1 to 10% by weight of an antiviral compound; and the balance being a solvent. The antiviral compound includes one or more selected from the group consisting of (A) metal hydroxide ([M1(OH)2]), (B) hydroxyapatite ([Ca 10 (PO4)6(OH)2]), and (C) a thermosensitive titanium dioxide photocatalyst doped with metal ([M2-TiO2]). M1 is Ca or Mg, and M2 is Pt, Cr, V, Mn, Fe, Zn, Cu, Ni, Zr, Mo, Ag, W, or Au. An antiviral composite resin composition is provided.

[0010] According to another embodiment of the present invention, there is provided an antiviral composite resin-coated steel sheet including a base steel sheet and an antiviral composite resin coating film containing the antiviral composite resin composition on at least one surface of the base steel sheet.

Effects of the Invention

[0011] According to the present invention, an antiviral composite resin composition is provided, which is a composition in which an inorganic oxide having a function of killing viruses and a thermosensitive photocatalyst are dispersed in a polymer resin composition. The coating film formed of the composition of the present invention has a function of effectively killing viruses adsorbed on the surface of the coating film in the form of droplets, that is, moisture containing viruses, by hydroxide anions and active oxygen species generated in the coating film. In particular, due to the strong cation and anion elution characteristics of the inorganic hydroxide and the complementary effect of the thermosensitive photocatalyst activated by infrared rays even in the absence of light, it is easy to adsorb droplets containing viruses and easy to kill viruses. Further, there is an advantage that the characteristics of the antiviral substance do not change significantly even during long-term use of the steel sheet for building materials.

Brief Description of the Drawings

[0012]

Figure 1

Embodiments for Carrying Out the Invention

[0013] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

[0014] According to an embodiment of the present invention, a composite resin composition containing a predetermined pigment and an antiviral substance is provided in a transparent resin composition composed of a urethane-modified polyester polymer resin, a curing agent, and a solvent. The coating film coated with such a resin composition of the present invention can form a coating film with excellent antiviral characteristics by floating an antiviral substance with a small specific gravity to the interface during curing.

[0015] The anti-viral composite resin composition according to an embodiment of the present invention can provide a coating film excellent in processability and chemical resistance, and by forming a urethane-modified polyester resin coating film in which a pigment and an anti-viral compound are mixed, each of the above components can form a composite network structure to provide excellent press processability and surface functionality.

[0016] For this purpose, the anti-viral composite resin composition according to an embodiment of the present invention can include 30 to 60% by weight of a urethane-modified polyester resin; 3 to 15% by weight of a curing agent; 0.1 to 10% by weight of a pigment; 0.1 to 10% by weight of an anti-viral compound; and the balance being a solvent, based on the total weight of the resin composition.

[0017] For example, the anti-viral composite resin composition according to an embodiment of the present invention can include 40 to 60% by weight of a urethane-modified polyester resin; 5 to 15% by weight of a curing agent; 5 to 8% by weight of a pigment; 1 to 8% by weight of an anti-viral compound; and the balance being a solvent, based on the total weight of the resin composition.

[0018] Hereinafter, each component of the resin composition of the present invention will be described in more detail.

[0019] <Binder Resin> The anti-viral composite resin composition according to an embodiment of the present invention can use a urethane-modified polyester resin as the binder resin of the coating film. The urethane-modified polyester resin is excellent in processability and chemical resistance of the coating film during curing.

[0020] As the urethane-modified polyester resin, one having a weight average molecular weight (MW) of 2000 to 30000 can be used.

[0021] Preferably, the urethane-modified polyester resin can have a weight average molecular weight (MW) of 5000 to 25000.

[0022] When the molecular weight of the urethane-modified polyester resin is less than 2,000, the chemical resistance and processability of the coating film are insufficient. When the molecular weight of the urethane-modified polyester resin exceeds 30,000, the storage stability and workability of the solution may deteriorate. As the urethane-modified polyester resin, those having a glass transition temperature of 0 to 70 °C can be used.

[0023] In addition, as the urethane-modified polyester resin, those preferably having a hydroxyl value of 10 to 300, more preferably 20 to 200 can be used.

[0024] When the hydroxyl value of the urethane-modified polyester resin exceeds 300, the chemical resistance of the coating film may decrease. When the hydroxyl value of the urethane-modified polyester resin is less than 10, the crosslinking property of the coating film may decrease.

[0025] In addition, the urethane-modified polyester resin can have an acid value of 5 to 30 mgKOH / g, preferably 10 to 25 mgKOH / g. When the acid value of the urethane-modified polyester resin exceeds 30 mgKOH / g the chemical resistance of the coating film may decrease. When the acid value of the urethane-modified polyester resin is 5 mgKOH / g less than that, the crosslinking property of the coating film may decrease.

[0026] The content of the urethane-modified polyester resin can be 30 to 60% by weight, more preferably 40 to 60% by weight, based on the whole antiviral composite resin composition. When outside the above range, the drying property may decrease during curing of the coating film, and a decrease in other physical properties may occur.

[0027] <Hardener> The antiviral composite resin composition according to an embodiment of the present invention can use one or more selected from the group consisting of an aziridine hardener, a melamine hardener, and an isocyanate hardener as a hardener for curing the binder resin.

[0028] The above-mentioned hardener has excellent reactivity and is not particularly limited. For example, an aziridine hardener represented by the following structural formula (a) can be used.

Chemical formula

[0029] In addition, as the melamine-based hardener of the present invention, an iminomelamine represented by the following structural formula (b) or a methylated melamine represented by the following structural formula (c) can be used.

Chemical formula

[0030]

Chemical formula

[0031] On the other hand, as the above-mentioned melamine hardener, without being limited thereto, one or more selected from the group consisting of iminomelamine of the above structural formula (b) and methylated melamine of the structural formula (c) can be used.

[0032] Compared with methylated melamine, iminomelamine has a fast curing reaction rate and is advantageous for high-speed curing. When its content increases, the degree of curing may increase and the hardness of the coating film may increase. On the other hand, fully substituted methylated melamine has a slow curing rate, but has good smoothness of the coating film and can provide excellent surface quality.

[0033] Therefore, the antiviral composite resin composition according to an embodiment of the present invention can improve the reaction rate by adding iminomelamine with a fast reaction rate while improving the surface quality of the coating film by using methylated melamine as a curing agent. Preferably, the iminomelamine of the above structural formula (b) and the methylated melamine of the structural formula (c) can be mixed and used in a weight ratio of 1:1 to 1:4.

[0034] In addition, as the isocyanate curing agent of the present invention, an isocyanate curing agent such as the monoisocyanate of the following structural formula (d) or the diisocyanate of the following structural formula (e) can be used.

Chemical formula

[0035]

Chemical formula

[0036] As the above isocyanate curing agent, the monoisocyanate (Monoisocyanate) of the structural formula (d) or the diisocyanate (Diisocyanate) of the structural formula (e) can be used.

[0037] In the above structural formula (d), R includes a methyl group, an ethyl group, a propyl group, a phenyl group, a 2-isopropylphenyl group, or a cyclohexyl group, etc.

[0038] In the above structural formula (e), R' is 1,3-phenylene, 1,4-phenylene, 2,4- tolylene -ene(2,4- tolylene e) , 2,6- tolylene -ene(2,6- tolylene e) , m-xylylene, 4,4’- dicyclohexylmethan -ene(4,4’- dicyclohexylmethan e) , 4,4’-methylenedipheny -yl(4,4’- methylenedipheny l) Examples include hexamethylene and the like.

[0039] The above-mentioned isocyanate curing agent can be used alone or in combination of two or more.

[0040] The content of the above curing agent can be 3 to 15% by weight, more preferably 5 to 15% by weight, based on the whole antiviral composite resin composition. When the content of the above curing agent is less than 3% by weight, the processability may become poor due to insufficient curing. When it exceeds 15% by weight, problems such as the coating film being easily cracked or crushed may occur due to overcuring.

[0041] <Pigment> The antiviral composite resin composition according to an embodiment of the present invention can contain a pigment having a unique hue. On the other hand, when the antiviral composite resin-coated steel sheet according to another embodiment of the present invention further includes a primer coating film, the primer coating film can also contain a pigment.

[0042] The antiviral composite resin composition according to the present invention can particularly have a unique hue composed of a combination of black, red, and white pigments. The above primer coating film can use a yellow or light yellow pigment, but is not limited thereto.

[0043] Various hues can be realized by blending the above black, red, yellow, and white pigments in a predetermined ratio.

[0044] The content of the above pigment can be 0.1 to 10% by weight, more preferably 5 to 8% by weight, based on the whole antiviral composite resin composition.

[0045] When the content of the above pigment is less than 0.1% by weight, it is difficult to obtain a high hiding power and a beautiful hue of the steel plate. When it exceeds 10% by weight, the viscosity of the solution becomes high, the workability deteriorates, and it may be difficult to obtain a beautiful surface appearance.

[0046] On the other hand, the primer coating film can contain 1 to 8% by weight of the pigment based on the total weight of the primer coating film.

[0047] Examples of the above black pigment include carbon black, carbon nanotubes, graphite, graphene, etc., and those containing at least one selected from the group consisting of ferric oxide (Fe2O3), titanium dioxide (TiO2), carbon black, carbon nanotubes, graphite and graphene can be used. The red pigment in the present invention includes ferric oxide (Fe2O3). Iron oxide has the advantages of non-toxicity, chemical stability, and the ability to produce various hues. Examples of the white pigment in the present invention include titanium dioxide (TiO2). Examples of the yellow pigment in the present invention include strontium chromate.

[0048] It is preferable to use a pigment having a low oil absorption amount. The oil absorption amount of the pigment can be less than 60%, and preferably can be in the range of 5 to 50%.

[0049] Also, the average particle size (particle diameter) of the above colored pigment is preferably in the range of the dry coating film thickness ± 5 μm. For example, the average particle size (particle diameter) of the above colored pigment can be in the range of 5 to 30 μm.

[0050] Also, the anti-viral composite resin composition according to an embodiment of the present invention can further contain an anti-rust pigment for strengthening the rust prevention property of the coating film in addition to the above colored pigment. As the above anti-rust pigment, one or more selected from the group consisting of colloidal silica, silica sol and alkali metal silicate can be used.

[0051] <Anti-viral compound> An antiviral composite resin composition according to an embodiment of the present invention can contain an antiviral compound.

[0052] As the above antiviral compound, (A) a metal hydroxide ([M1(OH)2]), where M1 is Ca or Mg.), (B) hydroxyapatite ([Ca 10 (PO4)6(OH)2]), and (C) a heat-sensitive titanium dioxide photocatalyst doped with a metal ([M2-TiO2]), where M2 is Pt, Cr, V, Mn, Fe, Zn, Cu, Ni, Zr, Mo, Ag, W, or Au.) One or more selected from the group consisting of can be used.

[0053] Titanium dioxide doped with a metal is known to exhibit visible light or heat-sensitive photocatalytic properties according to the following principle. Generally, a TiO2 photocatalyst requires 3.1 eV of light energy. However, when the above TiO2 is doped with a special metal or metal oxide, photoactivity is possible in a low energy region. An antiviral composite resin composition according to an embodiment of the present invention can contain heat-sensitive TiO2 activated by visible light and infrared rays using a TiO2 photocatalyst doped with a metal oxide.

[0054] The above antiviral compound can be used alone one selected from the group consisting of the above (A) metal hydroxide, (B) hydroxyapatite, and (C) heat-sensitive titanium dioxide photocatalyst doped with a metal.

[0055] Also, as shown in FIG. 1, the above antiviral compound can contain a combination of two or more selected from the group consisting of (A) a metal hydroxide, (B) hydroxyapatite, and (C) a heat-sensitive titanium dioxide photocatalyst doped with a metal.

[0056] For example, the above antiviral compound is one selected from the group consisting of the above (A) metal hydroxide and (B) hydroxyapatite and ;(C) A heat-sensitive titanium dioxide photocatalyst doped with a metal can be used in combination.

[0057] (C) Since the heat-sensitive titanium dioxide photocatalyst doped with a metal produces radical species, when combined with one selected from the group consisting of (A) metal hydroxide and (B) hydroxyapatite, it can exhibit more excellent antiviral performance.

[0058] When the content of the heat-sensitive titanium dioxide photocatalyst doped with (C) metal is used at a weight ratio of 3:1 to 1:3 with respect to the above (A) metal hydroxide or (B) hydroxyapatite, the most effective antiviral characteristics can be shown.

[0059] Also, the antiviral compound of the present invention can contain all of (A) metal hydroxide, (B) hydroxyapatite, and (C) heat-sensitive titanium dioxide photocatalyst doped with a metal. When the weight ratio of the above (A) metal hydroxide, (B) hydroxyapatite, and (C) heat-sensitive titanium dioxide photocatalyst doped with a metal is 1:1:1, the antiviral characteristics can show excellent characteristics similar to the above embodiments.

[0060] The content of the above antiviral compound can be 0.1 to 10% by weight, more preferably 1 to 8% by weight, based on the whole antiviral composite resin composition. When the content of the antiviral compound is less than 0.1% by weight, there may be a problem that the virus kill rate is low and the effect is insufficient, and when it exceeds 10% by weight, there may be a problem that the processability of the coating film deteriorates.

[0061] <Remaining solvent> In the antiviral composite resin composition according to one embodiment of the present invention, the remainder other than the above components formulated can be a solvent.

[0062] Also, the primer coating composition for forming the primer coating can also contain the remaining solvent. The solvent contained in the above primer coating composition can be the same as or different from the solvent used in the antiviral composite resin composition.

[0063] The above solvent can be, for example, one or more solvents selected from the group consisting of toluene, xylene, isopropanol, solvent naphtha, cellosolve, cellosolve acetate, and butyl cellosolve. The above solvent can be a single type or a mixture of two or more types.

[0064] The viscosity of the composition can vary depending on the content of the solvent. However, since the content of the solvent added to each of the above compositions can be appropriately adjusted as needed, it is not particularly limited here. For example, in the case of the antiviral composite resin composition, considering the coating amount, adhesion, etc., it can be adjusted to a viscosity that takes, for example, 20 to 200 seconds when discharged from a DIN cup (DIN, 53211).

[0065] The antiviral composite resin composition according to an embodiment of the present invention, in order to further improve the physical properties of the coating film, in addition to the above components, can further contain at least one or more additives such as wax, curing catalyst, pigment aggregation inhibitor, defoaming agent, leveling agent, etc. as needed. Any of the above additives can be appropriately used in the present invention as long as they are commonly used, and can be applied according to the normal mixing ratio.

[0066] The manufacturing method of the antiviral composite resin composition according to an embodiment of the present invention is not particularly limited. For example, a curing agent is dispersed in a urethane-modified poly ester resin to produce a resin composition. After that, a pigment for hue and rust prevention and an antiviral compound are further added and dispersed, and then it can be produced by putting it into a solvent.

[0067] <Antiviral Composite Resin Coated Steel Sheet> According to another embodiment of the present invention, there is provided an antiviral composite resin-coated steel sheet including a coating film formed by the above antiviral composite resin composition of the present invention. In describing the antiviral composite resin-coated steel sheet, all the descriptions of the above antiviral composite resin composition can be similarly applied.

[0068] The above antiviral composite resin-coated steel sheet can be provided by applying the above-described antiviral composite resin composition to at least one of one surface (first surface) and the other surface (second surface) of the base steel sheet.

[0069] As the above base steel sheet, a galvanized steel sheet can be used. Examples of the galvanized steel sheet include, but are not limited to, for example, hot-dip galvanized steel sheet (GI), alloyed hot-dip galvanized steel sheet (GA), electro-galvanized steel sheet (EG), aluminum-coated steel sheet, or zinc-aluminum-magnesium ternary alloy-coated steel sheet, etc.

[0070] The antiviral composite resin coating film on the above base steel sheet is formed by the above-provided antiviral composite resin composition, and the antiviral composite resin composition can include a urethane-modified polyester resin, a melamine curing agent, a pigment, and an antiviral compound as described above.

[0071] The composition of the above antiviral composite resin coating film can be manufactured using a composition including 30 to 60% by weight of a urethane-modified polyester resin, 3 to 15% by weight of a curing agent, 0.1 to 10% by weight of a pigment; 0.1 to 10% by weight of an antiviral compound; and the balance being a solvent, as described above.

[0072] For example, the above antiviral composite resin composition provided for manufacturing the antiviral composite resin-coated steel sheet of the present invention can include 40 to 60% by weight of a urethane-modified polyester resin; 5 to 15% by weight of a curing agent; 5 to 8% by weight of a pigment; 1 to 8% by weight of an antiviral compound; and the balance being a solvent, based on the total weight of the resin composition.

[0073] The above antiviral composite resin composition can be applied to a base steel plate and then dried to form an antiviral composite resin coating film. At this time, the coating method and the drying method are not particularly limited, and any method generally known in this technical field can be used. Drying can be carried out, but is not limited thereto, for example, by a hot air heating method, an infrared heating method, an induction heating method, a natural drying method, etc.

[0074] More specifically, the antiviral composite resin composition according to an embodiment of the present invention is preferably dried at 180 to 260 °C in terms of PMT (Peak Metal Temperature). Without being limited thereto, specifically, for example, in the case of the hot air heating method, the above composition can be dried by hot air treatment at an atmospheric temperature of 200 to 340 °C for 10 to 50 seconds.

[0075] The above antiviral composite resin coating film can be formed so that the dry film thickness is 3 to 40 μm, preferably 5 to 30 μm.

[0076] When the dry film thickness of the above antiviral composite resin coating film is less than 5 μm, the hue, hiding power, processability, and solvent resistance of the composite resin coating film may decrease. When the dry film thickness of the above antiviral composite resin coating film exceeds 30 μm, the manufacturing cost increases and the productivity decreases, which is not preferable.

[0077] <Primer coating film> The antiviral composite resin-coated steel plate according to another embodiment of the present invention is an antiviral composite resin-coated steel plate in which a primer coating film is formed on at least one side or both sides, and an antiviral composite resin coating film provided as an embodiment of the present invention is formed on one surface of the above primer coating film.

[0078] In the case of a steel plate including the above antiviral composite resin coating film (topcoat film), the primer coating film can be positioned as an undercoat film between the base steel plate and the antiviral composite resin coating film (topcoat film).

[0079] In the antiviral composite resin-coated steel sheet according to another embodiment of the present invention, the primer coating film further formed on the first surface and / or the second surface of the base steel sheet is not particularly limited. As a film that increases the adhesion between the base steel sheet and the antiviral composite resin coating film and imparts other physical properties required for steel sheets, such as paintability and corrosion resistance, to the steel sheet, any coating film known to be applicable between the base steel sheet and the antiviral composite resin coating film (top coating film) in this technical field may be used.

[0080] For example, the primer coating film composition for forming the primer coating film can be a composition composed of 40 to 60% by weight of a polyethylene polymer resin, 5 to 15% by weight of a melamine curing agent, 1 to 8% by weight of colloidal silica, and 1 to 8% by weight of a pigment, with the balance being a solvent. The balance solvent can be different from or the same as the solvent used as the balance solvent in the antiviral composite resin composition.

[0081] On the other hand, the primer coating film can be applied so that the dry film thickness is 2 to 7 μm, preferably 3 to 5 μm. If the thickness of the primer coating film exceeds 7 μm, the manufacturing cost may increase and the productivity may be low, which is not preferable. If the thickness of the primer coating film is 2 μm or less, there may be a problem that it is difficult to ensure the above quality characteristics.

[0082] The primer coating film is a coating for concealing the material, preventing rust, and for the hue, and is advantageous in terms of improving the hue and hiding power, processability, and corrosion resistance of the antiviral composite resin coating film.

[0083] In another embodiment of the present invention, when the antiviral composite resin coating film is formed only on one surface of the base steel sheet, it is preferable to form a resin coating film on the surface of the base steel sheet where the composite resin coating film is not formed, considering the processability and corrosion resistance of the steel sheet.

Examples

[0084] Examples Hereinafter, the present invention will be described in more detail through examples. However, the following examples are illustrative of specific embodiments of the present invention, and the present invention is not limited thereby.

[0085] Examples 1 to 27 and Comparative Examples 1 to 9 A urethane-modified polyester resin, a curing agent, a pigment, an antiviral compound, and the balance solvent were mixed in the contents shown in Examples 1 to 27 and Comparative Examples 1 to 9 of the following [Table 1], and then dispersed using a high-speed bead mill disperser to produce an antiviral composite resin composition.

[0086] As the above urethane-modified polyester resin, a resin having a weight average molecular weight of 16,000 to 20,000 (manufactured by KCC Corporation, glass transition temperature (Tg) of 10 to 30 ° C) was used.

[0087] As the above curing agent, as an aziridine-based curing agent, trimethylolpropane tris(β-N-aziridinyl)propionate, as a melamine-based curing agent, hexamethoxymethylmelamine, and as an isocyanate-based curing agent, toluene diisocyanate were used, respectively.

[0088] As the above pigment, as a black pigment, carbon black (Printex series of Evonik), as a red pigment, iron oxide, and as a white pigment, titanium dioxide were used, respectively. TM As the above antiviral compound, calcium hydroxide (Ca(OH)2) as the above (A) metal hydroxide or hydroxyapatite (Oszen Co., Ltd.) as (B) was mixed with a thermosensitive titanium dioxide photocatalyst doped with (C) metal in a ratio of 3:1 to 1:3 and used. In Examples 25 to 27 in which (A):(B):(C) were all included, they were mixed and used so that the weight ratio of each component was 1:1:1.

[0089]

[0090] ​For the remaining solvent, cellosolve acetate was used.

[0091] At this time, the heat-sensitive titanium dioxide photocatalyst doped with (C) metal was prepared using titanium compound [Ti(i-OC3H7)4], isopropyl alcohol, nitric acid, manganese compound [Mn(NO3)2], platinum compound [Pt(NH3)2], and methyl tertiary -toxy silane (Methyltertiarymeth -oxys ilane , MTMS ).

[0092] More specifically, 5 L of distilled water was placed in a reactor, 100 ml of nitric acid and 20 g of Mn(NO3)2 were dissolved, and after heating the temperature to 80 °C, 12.5 g of platinum compound [Pt(NH3)2] was added and stirred. In another reactor, 1500 g of titanium compound [Ti(i-OC3H7)4] and 150 ml of isopropyl alcohol were mixed and then added to the above solution. After cooling the mixed solution to room temperature, methyl tertiary meth -toxy silane (Methyltertiarymeth -oxys ilane , MTMS ) 10 g was added, and the generated precipitate was filtered and then dried at a temperature of 300 °C for production.

[0093]

Table 1

[0094] The above-prepared solution was roll-coated on a Zn-Al-Mg ternary alloy-plated steel sheet with a one-sided plating adhesion amount of 60 g / m 2 or the above alloy-plated steel sheet having a primer coating layer so that the dry film thickness of the antiviral composite resin composition of the above example was 15 to 20 μm, cured and dried at PMT (peak metal temperature) 232 °C, and then cooled to produce an antiviral composite resin-coated steel sheet having a composite resin coating layer as an example and a comparative example.

[0095] The above primer coating layer was formed to have a dry film thickness of 5 μm after drying using a composition consisting of 50% by weight of a polyethylene polymer resin, 10% by weight of a melamine curing agent, 5% by weight of colloidal silica, 5% by weight of a pale yellow pigment, and the balance being a solvent.

[0096] The surface properties of the composite resin coated steel sheet having the composite resin coating layer obtained by the above manufacturing process were evaluated, and the results are shown in [Table 2] and [Table 3].

[0097]

Table 2

[0098]

Table 3

[0099] The surface properties and their evaluations in the above [Table 2] and [Table 3] were carried out by the following method.

[0100] <Coating thickness> The coating thickness was measured with a non-destructive Portable coating thickness gauge.

[0101] <Appearance designability> The coating film hue was evaluated by the color difference value in comparison with a standard test piece of beige hue and expressed as follows. [Evaluation criteria] ◎: ΔE < 1.0 (very excellent), ○: 1.0 ≤ ΔE < 1.5 (excellent), △: 1.5 ≤ ΔE < 2.5 (inferior), ×: 2.5 < ΔE (very inferior)

[0102] <Gloss> The 60° specular reflection value was measured and evaluated using equipment from SHEEN.

[0103] <Pencil hardness> After drawing a 10 cm line at an angle of 45° with a load of 1000 ± 10 g using a Mitsubishi pencil (HB to 4H), it was evaluated based on the presence or absence of scratches.

[0104] <Corrosion Resistance Evaluation> The corrosion resistance was evaluated by the cyclic corrosion test (CCT). Salt spray (concentration 5%, spray pressure of 1 kg / cm at 35°C) was carried out for 5 hours under the condition of 95% relative humidity, followed by drying at 30% relative humidity and 70°C for 2 hours, and then treatment at 95% relative humidity and 50°C for 3 hours. One cycle was repeated 100 times, and the evaluation was based on the occurrence area of white rust on the surface of the steel plate. 2 After that, the steel plate was dried at 30% relative humidity and 70°C for 2 hours, and then treated at 95% relative humidity and 50°C for 3 hours. One cycle was repeated 100 times, and the evaluation was based on the occurrence area of white rust on the surface of the steel plate. [Evaluation Criteria] ◎: Corrosion area is 0%, ○: Corrosion area is 5% or less, △: Corrosion area is 5 - 30%, ×: Corrosion area is more than 30%

[0105] <Bending Processability Evaluation> For the anti-virus composite resin-coated steel plate, the surface of the steel plate was put into a vice and bent at 180° with a pressure of 1 kgf, and then tightened until it became flat (0T - bending). After attaching Scotch tape to the bent coating film, the evaluation was based on the occurrence of cracks and the peeling of the coating film on the tape when the coating film was peeled off. [Evaluation Criteria] ◎: No cracks and peeling, ○: Fine cracks can be seen, but no peeling of the coating film, △: Severe crack generation, no peeling of the coating film, ×: Peeling of the coating film along with cracks

[0106] <Chemical Resistance> When a gauze soaked in methyl ethyl ketone (MEK) with a 1 Kg load was rubbed back and forth with a force of 1 Kgf, it was judged by the number of times until the coating film peeled off. [Evaluation Criteria] ◎: 100 times or more, ○: 70 times or more and less than 100 times, △: 40 times or more and less than 70 times, ×: Less than 40 times

[0107] <Anti-Virus Property> <Short-Term Anti-Virus Property Evaluation> The anti-virus properties of the composite resin-coated steel plates of the examples and comparative examples were evaluated according to the ISO 21702 standard at the Institute of One Health, Jeonbuk National University. COVID-19 (3.2×10 6400 μL of the virus stock solution (TCID50 / ml) was dropped onto each of the control group and the composite resin-coated steel plate specimens (50×50 mm), covered with a polymer film (40×40 mm, Polyethylene film), and then allowed to contact at room temperature for 2 hours, and then recovered with 1.9 mL of culture medium. The culture medium solution was serially diluted until it reached 10 -1 ~10 -5 Each dilution was used to infect the monkey host cells (Vero E6 Cell), and then cultured at 37°C for 72 hours. After dropping MTT staining solution (Triazolium) onto each cultured well, the color change was observed to determine the survival of the host cells. The concentration value (TCID50) of the cells surviving in the above wells was calculated, and the virus inactivation rate was quantitatively evaluated by comparing with the control group.

[0108] <Long-term antiviral property evaluation> After irradiating the above composite resin-coated steel plate under QUV-B evaluation conditions for 1000 hours, the antiviral property was evaluated in the same manner as the above short-term antiviral property evaluation. [Evaluation criteria] Virus inactivation rate (X) is (◎): 95% ≤ X, (○): 90 ≤ X < 95%, (△): 80 ≤ X < 90%, (×): X < 80%

[0109] In the antiviral composite resin-coated steel plate of the present invention, the antiviral composite resin composition has a beautiful appearance hue when coated with a dry film thickness of 15 μm, and is excellent in appearance design. However, when a primer layer is included under the upper coating layer of the composite resin, it has been found that a more beautiful hue is exhibited. Such an effect is judged to be the result of an increase in the hiding effect of the base steel plate as the coating thickness increases due to the primer coating, which is the undercoat film, and a decrease in the diffuse reflection of light, resulting in an increase in the vividness of the hue by the pigment.

[0110] In the antiviral composite resin-coated steel sheet of the present invention, the antiviral composite resin composition is effective when used alone with (a) metal hydroxide or (b) hydroxyapatite, but when added together with (c) a thermosensitive titanium dioxide photocatalyst doped with metal, the virus kill rate increased significantly. Such results are due to the fact that when droplets containing the virus adhere to the coating surface of the above steel sheet, the action of active oxygen generated by the action of (c) a thermosensitive titanium dioxide photocatalyst doped with metal, together with the cations and anions generated by (a) metal hydroxide or (b) hydroxyapatite, promotes the death of the virus. In addition, in the long-term durability evaluation of the above antiviral composite resin-coated steel sheet, excellent results were shown without a decrease in antiviral properties.

Claims

1. 30 to 60% by weight of a urethane-modified polyester binder resin; 3 to 15% by weight of a curing agent; 0.1 to 10% by weight of a pigment; 0.1 to 10% by weight of an antiviral compound; and the balance being a solvent, The antiviral compound includes one or more selected from the group consisting of (A) metal hydroxide ([M １ (OH) ２ ), (B) hydroxyapatite ([Ca １０ (PO ４ ) ６ (OH) ２ ), and (C) thermosensitive titanium dioxide photocatalyst doped with metal ([M ２ -TiO ２ ). The aforesaid M １ is Ca or Mg, The above-mentioned M ２ is an antiviral composite resin composition that is Pt, Cr, V, Mn, Fe, Zn, Cu, Ni, Zr, Mo, Ag, W or Au.

2. The antiviral composite resin composition according to Claim 1, wherein the urethane-modified polyester binder resin has a weight average molecular weight (MW) of 2,000 to 30,000.

3. The antiviral composite resin composition according to Claim 1, wherein the urethane-modified polyester binder resin has a hydroxyl value of 10 to 300.

4. The antiviral composite resin composition according to Claim 1, wherein the urethane-modified polyester binder resin has an acid value of 5 to 30 mgKOH / g.

5. The antiviral composite resin composition according to Claim 1, wherein the curing agent is one or more selected from the group consisting of aziridine curing agents, melamine curing agents, and isocyanate curing agents.

6. The antiviral composite resin composition according to Claim 5, wherein the isocyanate curing agent is one or more selected from the group consisting of compounds represented by the following Structural Formula (d) and the following Structural Formula (e). 【Chemical 1】 (In the Structural Formula (d), R is a methyl group, an ethyl group, a propyl group, a phenyl group, a 2-isopropylphenyl group, or a cyclohexyl group.) 【Chemical Formula 2】 (In the Structural Formula (e), R' is 1,3-phenylene, 1,4-phenylene, tolylene-2,4, tolylene-2,6, m-xylylene, dicyclohexylmethane 4,4', methylenediphenyl 4,4', or hexamethylene.)

7. The pigment is at least one selected from the group consisting of ferric oxide (Fe ２ O ３ ), titanium dioxide (TiO ２ ), carbon black, carbon nanotubes, graphite, and graphene, and the antiviral composite resin composition according to claim 1.

8. The antiviral composite resin composition according to Claim 1, wherein the pigment has an average particle size of 5 to 30 μm.

9. The antiviral composite resin composition according to Claim 1, further comprising one or more rust-preventive pigments selected from the group consisting of colloidal silica, silica sol, and alkali metal silicate.

10. The antiviral composite resin composition according to Claim 1, wherein the antiviral compound is a combination of any one of the above (A) metal hydroxide and (B) hydroxyapatite, and (C) a heat-sensitive titanium dioxide photocatalyst doped with a metal.

11. The antiviral compound is the antiviral composite resin composition according to claim 10, wherein the weight ratio of any one of the (A) metal hydroxide and (B) hydroxyapatite to the (C) thermosensitive titanium dioxide photocatalyst doped with metal is 3:1 to 1:

3.

12. The antiviral compound is the antiviral composite resin composition according to claim 1, which contains all of the (A) metal hydroxide, (B) hydroxyapatite, and (C) thermosensitive titanium dioxide photocatalyst doped with metal.

13. The antiviral composite resin composition according to claim 12, wherein the weight ratio of the (A) metal hydroxide, (B) hydroxyapatite, and (C) thermosensitive titanium dioxide photocatalyst doped with metal is 1:1:

1.

14. The antiviral composite resin composition according to claim 1, wherein the remaining solvent is one or more selected from the group consisting of toluene, xylene, isopropanol, solvent naphtha, cellosolve, cellosolve acetate, and butyl cellosolve.

15. Base steel plate; and An antiviral composite resin coated steel plate including an antiviral composite resin coating film containing the antiviral composite resin composition according to any one of claims 1 to 14 on at least one surface of the base steel plate.

16. The antiviral composite resin coated steel plate according to claim 15, wherein the base steel plate is a hot-dip galvanized steel sheet (GI), an alloyed hot-dip galvanized steel sheet (GA), an electro-galvanized steel sheet (EG), an aluminum-coated steel sheet, or a zinc-aluminum-magnesium ternary alloy coated steel sheet.

17. The antiviral composite resin coated steel plate according to claim 15, wherein the antiviral composite resin coating film has a dry film thickness of 3 to 40 μm.

18. The antiviral composite resin coated steel plate according to claim 15 further includes a primer coating film between the base steel plate and the antiviral composite resin coating film, The primer coating film is manufactured using a composition containing 40 to 60% by weight of a polyethylene polymer resin, 5 to 15% by weight of a melamine curing agent, 1 to 8% by weight of colloidal silica, and 1 to 8% by weight of a pigment and the remaining solvent.

19. The antiviral composite resin coated steel plate according to claim 18, wherein the primer coating film has a dry film thickness of 2 to 7 μm.

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