Antibacterial coating, antibacterial cookware and preparation method of antibacterial coating

Abstract

The invention discloses an antibacterial coating, an antibacterial pot and a preparation method thereof, and belongs to the technical field of cooking utensils. The antibacterial coating is prepared from the following raw materials in percentage by mass: 20%-30% of siloxane, 18%-27% of silica sol, 1%-5% of zwitterionic sulfobetaine silane, 1%-10% of a cosolvent, 1%-5% of polysiloxane, 0.1%-0.5% of an acid catalyst and the balance of water. The coating disclosed by the invention takes zwitter-ion sulphobetaine silane as an antibacterial agent, so that the long-acting and lasting antibacterial property and coating uniformity of a coating can be remarkably improved, and the problem that after cooking utensils such as cookware are used for a long time, the surface of the cookware is oxidized and discolored or the antibacterial property of the cookware is reduced is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of cooking utensils, and in particular to an antibacterial coating, an antibacterial cookware and a preparation method thereof. Background Art

[0002] Antibacterial agents are generally added to the coating of cooking utensils such as pots to improve the antibacterial properties. The antibacterial agents commonly added are mainly inorganic antibacterial agents such as nanosilver and nanozinc oxide.

[0003] In order to ensure safety performance, the coating used for cookware is generally formed by water-based coatings. However, inorganic antimicrobial agents are difficult to disperse and easy to agglomerate in water. The antibacterial performance of sustained-release antimicrobial agents such as metal ions will gradually decrease to ineffectiveness with the use time, resulting in the antibacterial performance of the coating having a service life and being unable to provide long-term antibacterial effects. In addition, inorganic antimicrobial agents such as metallic silver ions will generate gray silver oxide when exposed to air, causing the coating to discolor, affecting the appearance of the cookware surface and safety of use. Summary of the invention

[0004] In view of the above problems, the present invention provides an antibacterial coating, an antibacterial cookware and a preparation method thereof, aiming to improve the long-term antibacterial property of the coating.

[0005] In a first aspect, the present invention provides an antibacterial coating comprising the following raw materials by mass fraction: Siloxane 20%-30%, silica sol 18%-27%, zwitterionic sulfobetaine silane 1%-5%, cosolvent 1%-10%, polysiloxane 1%-5%, acid catalyst 0.1%-0.5%, and the balance is water.

[0006] In one embodiment, the structural formula of siloxane is as shown in formula (I): Formula (I), Among them, R 1 Including one of hydrogen, amino, mercapto, glycidyloxy, chloro, R 2 It includes one of methyl and ethyl, and m is 1 or 3.

[0007] In one embodiment, the siloxane includes at least one of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, chloropropyltrimethoxysilane, and chloropropyltriethoxysilane.

[0008] In one embodiment, the zwitterionic sulfobetaine silane has a structural formula as shown in formula (II): Formula (II), Among them, R 2 Including one of methyl and ethyl, R 3 It includes one of a methylene group, a secondary amine group, and an amine ester group, wherein m is 1 or 3, and n is 1, 2 or 3.

[0009] In one embodiment, the zwitterionic sulfobetaine silane includes at least one of N,N-dimethylaminoethylcarbamatepropyltriethoxysilanesulfonic acid inner salt, N,N-dimethylaminopropylaminomethyltriethoxysilanesulfonic acid inner salt, and 3-[dimethyl(3-(trimethoxysilyl)propylamino)]propane-1-sulfonate.

[0010] In one embodiment, the solid content of the silica sol is 30%-50%; and / or the pH of the silica sol is 8-10; and / or the particle size DV50 of the silica sol is 10nm-100nm.

[0011] In one embodiment, the number average molecular weight of the polysiloxane is 1,000-100,000.

[0012] In one embodiment, the polysiloxane includes at least one of polydimethylsiloxane, polymethylphenylsiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, epoxy-modified polysiloxane, and amino-modified polysiloxane.

[0013] In one embodiment, the co-solvent includes at least one of an alcohol solvent and an ether solvent.

[0014] In one embodiment, the co-solvent includes at least one of methanol, ethanol, isopropanol, propylene glycol methyl ether, and ethylene glycol butyl ether.

[0015] In one embodiment, the acid catalyst includes at least one of formic acid, acetic acid, p-toluenesulfonic acid, hydrochloric acid, sulfuric acid, and nitric acid.

[0016] In one embodiment, the antimicrobial coating further comprises a pigment dispersion, which comprises a pigment, a dispersant, a defoaming agent, a pH adjuster, a thickener and water.

[0017] In one embodiment, the pigment includes at least one of copper chrome black, iron manganese black, titanium dioxide, cobalt blue, cobalt green, cobalt black, titanium chrome brown, iron oxide red, iron oxide yellow, bismuth vanadate, and nickel titanium yellow; and / or, the dispersant includes at least one of BYK-191 and DISPERBYK-101N; and / or, the defoamer includes at least one of BYK1709, BYK088, and BYK024; and / or, the pH adjuster includes at least one of hydrochloric acid, acetic acid, sodium hydroxide, and sodium bicarbonate; and / or, the thickener includes at least one of bentonite, fumed silica, and BYK410.

[0018] In a second aspect, the present invention provides an antibacterial cookware, comprising a pot body and an antibacterial coating, wherein the antibacterial coating is arranged on the inner surface of at least a portion of the pot body, the antibacterial coating comprises an antibacterial surface layer, the antibacterial surface layer is formed by any of the above-mentioned antibacterial coatings, the antibacterial surface layer comprises antibacterial segments and siloxane groups, and the interior of the antibacterial coating and / or at least a portion of the surface away from the pot body has a low surface energy segment; wherein the antibacterial segment is grafted to the low surface energy segment through the siloxane group.

[0019] In one embodiment, the antibacterial coating further includes a non-stick bottom layer, which is disposed between the antibacterial surface layer and the inner surface of the pot body; wherein at least a portion of the surface of the antibacterial surface layer includes an antibacterial segment, and the antibacterial segment includes a zwitterionic sulfobetaine silane segment.

[0020] In one embodiment, the low surface energy segment includes a first low surface energy segment and a second low surface energy segment, the first low surface energy segment is arranged on the surface of the non-stick base layer facing the antibacterial surface layer, and the second low surface energy segment is arranged on the surface of the antibacterial surface layer facing the non-stick base layer, wherein the second low surface energy segment is grafted to the first low surface energy segment through a siloxane group.

[0021] In one embodiment, the low surface energy segment has a polysiloxane group, and the polysiloxane group includes at least one of polydimethylsiloxane, polymethylphenylsiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, epoxy-modified polysiloxane, and amino-modified polysiloxane.

[0022] In one embodiment, the non-stick bottom layer comprises the following raw materials in mass fractions: 20%-30% siloxane, 18%-27% silica sol, 1%-5% polysiloxane, 1%-10% co-solvent, and the balance is water.

[0023] In one embodiment, the thickness of the non-stick bottom layer is 15 μm-25 μm, and the thickness of the antibacterial surface layer is 5 μm-15 μm.

[0024] In one embodiment, the surface hardness of the antimicrobial coating is 6H-9H.

[0025] In one embodiment, the structural formula of the segment formed by the antibacterial segment, the siloxane group and the low surface energy segment is as shown in formula (III): Formula (III), Among them, R 1 Including one of hydrogen, amino, mercapto, glycidyloxy, chloro, R 3 It includes one of a methylene group, a secondary amine group, and an amine ester group, wherein m is 1 or 3, and n is 1, 2 or 3.

[0026] In one embodiment, the pot body is a metal pot body, which includes a pot side wall and a pot bottom surface that is concave on the inner surface, wherein the inner surface of the pot side wall and / or the pot bottom surface is provided with an antibacterial coating, and at least part of the surface of the antibacterial coating forms a plurality of protrusions.

[0027] In a third aspect, the present invention provides a method for preparing an antibacterial cookware, comprising: providing a cookware body; coating any of the above-mentioned antibacterial coatings on the inner surface of at least a portion of the cookware body; drying the cookware body coated with the antibacterial coating at 120°C-170°C for 3min-10min, and then curing at 250°C-300°C for 10min-25min to obtain the antibacterial cookware.

[0028] In one embodiment, providing the pot body includes: cleaning, degreasing and / or sandblasting the surface of the pot body, and then heating the pot body to 40°C-50°C.

[0029] In one embodiment, coating any of the above-mentioned antibacterial coatings on at least a portion of the inner surface of the pot body comprises: providing a non-stick coating, the non-stick coating comprising the following raw materials in mass fractions: 20%-30% siloxane, 18%-27% silica sol, 1%-5% polysiloxane, 1%-10% cosolvent, and the balance being water; coating the non-stick coating on at least a portion of the inner surface of the pot body, drying the pot body coated with the non-stick coating at 120°C-170°C for 3min-10min, and then curing at 250°C-300°C for 10min-25min to obtain a non-stick base layer; coating the antibacterial coating on at least a portion of the surface of the non-stick base layer.

[0030] The antibacterial coating of the present invention uses zwitterionic sulfobetaine silane as an antibacterial agent, one end of which is a zwitterionic betaine compound, which can inhibit the formation of biofilm, hinder bacterial adhesion, and destroy the cell membrane structure of bacteria through electrostatic adsorption, thereby achieving the purpose of sterilization and antibacterial.

[0031] Zwitterionic sulfobetaine silane contains both cations and anions and is an amphoteric surfactant that can interact with water molecules in water through electrostatic effects, helping to disperse evenly in water, thereby helping to improve the antibacterial properties of the coating.

[0032] In addition, siloxane and zwitterionic sulfobetaine silane can be catalytically hydrolyzed under the action of an acid catalyst, and the hydrolyzed siloxane, zwitterionic sulfobetaine silane, silica sol, and polysiloxane are cross-linked through hydroxyl dehydration condensation to form a dense coating, and zwitterionic sulfobetaine silane segments and polysiloxane segments are grafted and fixed in the antibacterial coating by the silicon-oxygen-silicon bond (Si-O-Si) of the siloxane group, and the chemical bond is more firmly bonded, so that a long-lasting and lasting antibacterial effect can be obtained. In addition, the present invention does not use metal antibacterial ions such as nanosilver as antibacterial agents, which reduces the problem of surface oxidation discoloration of cooking utensils such as pots after long-term use.

[0033] Secondly, the antibacterial coating includes a non-stick base layer and an antibacterial surface layer, wherein at least part of the surface of the antibacterial surface layer includes zwitterionic sulfonyl betaine silane segments and / or polysiloxane segments, the zwitterionic sulfonyl betaine silane segments have long-lasting and lossless antibacterial properties, and the polysiloxane segments have low surface energy and excellent hydrophobic and non-stick properties. Under the action of chemical bonding, the two make the antibacterial coating have long-lasting antibacterial and non-stick properties, and have high hardness. When coated on the surface of antibacterial cookware, it can meet the requirements of wear resistance and corrosion resistance, and the antibacterial coating has a strong bonding force to the surface of the cookware substrate. The grafting connection of siloxane groups further improves the bonding force and anti-scratch effect between the non-stick base layer and the antibacterial surface layer, does not affect the service life of the antibacterial cookware, and obtains long-lasting antibacterial and non-stick properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic longitudinal section diagram of an antibacterial cookware in some embodiments of the present invention; Figure 2 Schematic diagram of longitudinal section of antibacterial cookware in other embodiments of the present invention.

[0035] Reference numerals 100. antibacterial cookware; 11. cooker body; 111. cooker side wall; 112. cooker bottom; 12. antibacterial coating; 121. antibacterial surface layer; 122. non-stick bottom layer. DETAILED DESCRIPTION

[0036] The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are therefore only used as examples and are not intended to limit the scope of protection of the present invention.

[0037] "Scope" disclosed in the present invention is limited in the form of lower limit and upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The scope limited in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a specific parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3,4 and 5 are listed, the following scope can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present invention, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0038] In the description of the embodiments of the present invention, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0039] In the description of the embodiments of the present invention, the term "multiple" refers to more than two (including two), similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces). The term "at least one" refers to one or more.

[0040] Reference to "embodiments" in the present invention means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] At present, inorganic antibacterial agents such as nanosilver and nanozinc oxide are usually added to water-based coatings used for cooking utensils such as inner pots, inner pots, frying pans, and soup pots to improve the antibacterial performance. However, nanosilver and nanozinc oxide particles are small in size, large in surface area, and have high surface energy, so they will spontaneously agglomerate in water. In addition, there is a strong van der Waals force between nanoparticles, and this attraction will also cause nanosilver and nanozinc oxide particles to approach each other and agglomerate. Therefore, inorganic antibacterial agents such as nanosilver and nanozinc oxide have problems of poor dispersibility and easy agglomeration in water, which leads to a decrease in the long-term antibacterial performance of the coating.

[0042] In order to solve the above problems, the present invention uses zwitterionic sulfobetaine silane as an antibacterial agent, one end of which is a zwitterionic betaine compound, which can inhibit the formation of biofilm, hinder bacterial adhesion, and can destroy the cell membrane structure of bacteria through electrostatic adsorption, thereby achieving the purpose of sterilization and antibacterial. Siloxane and zwitterionic sulfobetaine silane can be catalytically hydrolyzed under the action of an acid catalyst, and the hydrolyzed siloxane, zwitterionic sulfobetaine silane, silica sol, and polysiloxane are cross-linked through hydroxyl dehydration condensation to form a dense coating, and the zwitterionic sulfobetaine silane chain segment is fixed in the coating, and the chemical bond is more firmly bonded, so that a long-lasting and efficient antibacterial effect can be obtained.

[0043] According to some embodiments of the present invention, the present invention provides an antibacterial coating, comprising the following raw materials in mass fractions: 20%-30% siloxane, 18%-27% silica sol, 1%-5% zwitterionic sulfobetaine silane, 1%-10% cosolvent, 1%-5% polysiloxane, 0.1%-0.5% acid catalyst, and the balance being water.

[0044] Zwitterionic sulfobetaine silane refers to a compound including a zwitterionic betaine structure at one end and a silane group at the other end.

[0045] The zwitterionic betaine structure includes a cationic group and an anionic group. The cationic group will electrostatically attract the anionic phospholipid head on the cell membrane, and the anionic group will also interact with the cationic components on the cell membrane, thereby disrupting the normal structure and function of the cell membrane, increasing the permeability of the cell membrane, causing the leakage of substances in the cell, and ultimately causing the death of bacteria. That is, the zwitterionic betaine structure can destroy the bacterial cell membrane structure through electrostatic adsorption, thereby achieving the purpose of sterilization and antibacterial. In addition, the zwitterionic betaine structure has a strong hydrophilicity and forms a highly hydrated layer on the surface of the bacteria. This hydrated layer can prevent the bacteria from contacting and exchanging with nutrients, water, etc. in the surrounding environment. At the same time, the presence of the hydrated layer can also hinder the mutual aggregation and adhesion between bacteria, reduce the formation of bacterial biofilms, and make bacteria more susceptible to the influence of the external environment and the attack of the immune system. That is, the zwitterionic betaine structure can inhibit the formation of biofilms and hinder bacterial adhesion, thereby achieving an antibacterial effect.

[0046] In addition, zwitterionic sulfobetaine silane contains both cations and anions, and is an amphoteric surfactant that can interact with water molecules in water through electrostatic effects, which helps to disperse evenly in water, thereby helping to improve the antibacterial properties of the coating. Zwitterionic sulfobetaine silane is hydrophilic. The larger the amount added, the better the antibacterial effect, but it will affect its non-stick properties. In order to take into account both antibacterial and non-stick properties, the amount of zwitterionic sulfobetaine silane added needs to be controlled below 5%, so that good antibacterial properties can be achieved while meeting the non-stick requirements.

[0047] Silica sol refers to a solution formed by dispersing nano-scale silica particles in water. The silica particles in the silica sol can fill the microscopic pores of the coating, reducing the stress concentration points inside the coating, so that the coating can better disperse the stress when subjected to external forces (such as scratches, collisions, etc.). Therefore, silica sol can enhance the mechanical strength of the coating.

[0048] Polysiloxane is a type of polymer with a silicon-oxygen-silicon (Si-O-Si) bond as the main chain and organic groups attached to the silicon atom. The main chain of polysiloxane is composed of silicon-oxygen-silicon bonds, where the bond energy of the silicon-oxygen bond is high and the molecular chain is relatively flexible. At the same time, the organic groups (such as methyl) attached to the silicon atom make the polysiloxane molecule have a low surface energy, so that the coating surface is not easily wetted by other substances. In addition, the addition of polysiloxane enables the coating to form a relatively smooth surface after curing, reducing the friction and contact area between food and cooking utensils. Therefore, polysiloxane can make the coating non-stick, and polysiloxane does not contain fluorine. Compared with fluorine-containing non-stick coatings, it is more environmentally friendly and durable. The addition amount of polysiloxane is 1%-5%. Too much addition will cause oil floating on the coating surface, and too little addition will cause the non-stick property of the coating to deteriorate.

[0049] The silane groups of siloxane and zwitterionic sulfobetaine can be hydrolyzed under acid catalysts, and the siloxy groups are converted into active silanol groups. The hydrolyzed siloxane, zwitterionic sulfobetaine silane, silica sol, and polysiloxane form a dense coating through hydroxyl dehydration condensation cross-linking. The zwitterionic sulfobetaine silane segments are fixed in the coating, and the chemical bonds are more firmly bonded, thereby achieving a long-lasting and efficient antibacterial effect.

[0050] The antibacterial coating of the present invention uses zwitterionic sulfobetaine silane as an antibacterial agent, and the antibacterial agent can be evenly dispersed in the water-based coating system, which helps to improve the antibacterial property of the coating.

[0051] According to some embodiments of the present invention, the structural formula of siloxane is shown in formula (I): Formula (I), Among them, R 1 Including one of hydrogen, amino, mercapto, glycidyloxy, chloro, R 2 It includes one of methyl and ethyl, and m is 1 or 3.

[0052] The structural formula of glycidyloxy is -O-(CH2)3-.

[0053] On the one hand, siloxane exists as a film-forming substance for coatings. On the other hand, siloxane will hydrolyze and react with silica sol, polysiloxane, etc. The hydrolysis reaction equation of siloxane is shown below: .

[0054] According to some embodiments of the present invention, the siloxane includes at least one of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, chloropropyltrimethoxysilane, and chloropropyltriethoxysilane.

[0055] According to some embodiments of the present invention, the zwitterionic sulfobetaine silane has a structural formula as shown in formula (II): Formula (II), Among them, R 2 Including one of methyl and ethyl, R 3 It includes one of a methylene group, a secondary amine group, and an amine ester group, wherein m is 1 or 3, and n is 1, 2 or 3.

[0056] The structural formula of methylene is -CH2-, and the structural formula of secondary amine is -NH-. Amine ester group is a functional group containing both amino group (-NH2, -NHR or -NR2, R is an organic group such as alkyl) and ester group (-COOR', R' is an organic group such as alkyl), and is generally generated by the reaction of amino group and carbonate.

[0057] On the one hand, zwitterionic sulfobetaine silane exists as an antibacterial agent for coatings. On the other hand, its silane group can be hydrolyzed and react with silica sol, polysiloxane, etc. The hydrolysis reaction equation of zwitterionic sulfobetaine silane is shown below: .

[0058] The reaction equation of the hydrolyzed zwitterionic sulfobetaine silane, siloxane, silica sol and polysiloxane is shown below: .

[0059] According to some embodiments of the present invention, the zwitterionic sulfobetaine silane includes at least one of N,N-dimethylaminoethylcarbamatepropyltriethoxysilanesulfonic acid inner salt, N,N-dimethylaminopropylaminomethyltriethoxysilanesulfonic acid inner salt, and 3-[dimethyl(3-(trimethoxysilyl)propylamino)]propane-1-sulfonate.

[0060] In some embodiments, the preparation method of N,N-dimethylaminoethylcarbamate propyl triethoxysilane sulfonic acid inner salt comprises the following steps: taking isocyanate propyl triethoxysilane and N,N-dimethylethanolamine in a molar ratio of 1:1, mixing them at room temperature, stirring the reaction for 12 hours to obtain an intermediate product and dissolving it with tetrahydrofuran, slowly adding 1,3-propane sultone to the above solution, the amount of 1,3-propane sultone added is equimolar to N,N-dimethylethanolamine, stirring at room temperature for 12 hours, nitrogen protection throughout the process and strict waterproofing, collecting the white precipitate, and vacuum drying at 50°C to obtain N,N-dimethylaminoethylcarbamate propyl triethoxysilane sulfonic acid inner salt.

[0061] In some embodiments, the preparation method of N,N-dimethylaminopropylamine methyltriethoxysilane sulfonic acid inner salt comprises the following steps: taking chloromethyltriethoxysilane and triethylamine in a molar ratio of 1:1 in a flask, slowly adding 3-dimethylaminopropylamine in an amount equimolar to triethylamine, and refluxing at 70°C for 10 hours. The whole process is protected by nitrogen and strictly waterproof. The product is filtered to remove the amine salt precipitate, and the filtrate is purified by reduced pressure distillation to obtain the corresponding intermediate; taking the intermediate and 1,3-propane sultone in a molar ratio of 1:1, dissolving them in tetrahydrofuran to prepare a 2 mol / L solution, stirring and reacting at room temperature for 12 hours. The whole process is protected by nitrogen and strictly waterproof, collecting the brown precipitate, and vacuum drying at 50°C to obtain N,N-dimethylaminopropylamine methyltriethoxysilane sulfonic acid inner salt.

[0062] In some embodiments, the preparation method of 3-[dimethyl(3-(trimethoxysilyl)propylamino)]propane-1-sulfonate comprises the following steps: (N,N-dimethyl-3-aminopropyl)trimethoxysilane and 1,3-propane sultone are taken in a molar ratio of 1:1, dissolved in tetrahydrofuran to prepare a 2 mol / L solution, and stirred at room temperature for 12 hours. The whole process is protected by nitrogen and strictly waterproofed, and the white precipitate is collected and vacuum dried at 50°C to obtain 3-[dimethyl(3-(trimethoxysilyl)propylamino)]propane-1-sulfonate.

[0063] According to some embodiments of the present invention, the solid content of the silica sol is 30%-50%; and / or the pH of the silica sol is 8-10; and / or the particle size D of the silica sol is V 50 is 10nm-100nm.

[0064] Silica sol refers to a solution formed by dispersing nano-scale silica particles in water. Therefore, the solid content of silica sol refers to the mass proportion of silica particles in silica sol. For example, the solid content of silica sol can be 30%, 32%, 34%, 36%, 38%, 40%, 43%, 45%, 48% or 50%. When the solid content of silica sol is between 30% and 50%, it helps to improve the adhesion of the coating; in addition, when the solid content of alkaline silica sol is between 30% and 50%, it is conducive to full reaction.

[0065] The pH value of silica sol is between 8 and 10, which means that the silica sol is alkaline silica sol. Alkaline silica sol can form a good chemical bond with the metal base surface of the pot body, so that the coating can be tightly attached to the surface of the pot body.

[0066] Particle size D of silica sol V 50 refers to the particle size D of the silica particles in the silica sol V 50, the particle size Dv50 refers to the particle size corresponding to when the cumulative particle size distribution percentage reaches 50% in the particle size distribution. V 50 can be 10nm, 20nm, 30nm, 40nm, 50nm, 60nm, 70nm, 80nm, 90nm or 100nm. The particle size D of the silica sol V When 50 is between 10nm and 100nm, on the one hand, the silica sol has good stability and is not prone to flocculation; on the other hand, a coating with good density can be obtained, which helps to improve the durability, corrosion resistance and mechanical properties of the coating.

[0067] According to some embodiments of the present invention, the number average molecular weight of the polysiloxane is 1,000-100,000.

[0068] Polymers generally include polymers of various molecular weights, and the number-average molecular weight is the molecular weight averaged by the number of polymer molecules, specifically the molecular weight of all molecules multiplied by their corresponding number of molecules, then these products are added, and finally the average value obtained by dividing by the total number of molecules. Exemplarily, the number-average molecular weight of polysiloxane can be 1000, 3000, 5000, 8000, 10000, 30000, 50000, 80000 or 100000. When the number-average molecular weight of polysiloxane is between 1000-100000, on the one hand, the liquid repellency of polysiloxane is good, which helps to improve the non-stickiness of the coating; on the other hand, the lubricating effect of the polysiloxane of this molecular weight is good. When the molecular weight is too large, the polymer chains enriched on the surface will be entangled with each other, thereby reducing its mobility, and random wrinkles of nanometer scale will appear due to the internal stress during the curing process, and the presence of these wrinkles will affect the lubrication effect.

[0069] According to some embodiments of the present invention, the polysiloxane includes at least one of polydimethylsiloxane, polymethylphenylsiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, epoxy-modified polysiloxane, and amino-modified polysiloxane.

[0070] Polydimethylsiloxane has a very low surface energy and can obtain a coating with excellent non-stick properties. Compared with polydimethylsiloxane, polymethylphenylsiloxane has better heat resistance, can withstand higher temperatures, and can maintain the integrity of the coating at high temperatures.

[0071] Polyether-modified polysiloxane refers to a polymer obtained by introducing a polyether segment into the polysiloxane structure. The introduction of the polyether segment makes the coating have good wettability and enables the liquid to spread better on the coating surface. In addition, polyether-modified polysiloxane has good compatibility with other ingredients and can make the coating system more stable.

[0072] The introduction of alkyl groups in alkyl-modified polysiloxane enhances the thermal stability of polysiloxane, making the coating less prone to decomposition and aging in high-temperature cooking environments; in addition, the presence of alkyl groups can increase the flexibility of the coating, enabling the coating to withstand the collisions and impacts that the cookware is subjected to during use.

[0073] The introduction of fluorine in fluorine-modified polysiloxane can further reduce the surface energy, thereby further improving the non-stickiness of the coating. The presence of epoxy groups in epoxy-modified polysiloxane enhances the adhesion between the coating and the substrate and the components inside the coating, so that the coating can firmly adhere to the surface of the substrate and is not easy to peel off. The introduction of amino groups in amino-modified polysiloxane increases the flexibility and elasticity of the coating, allowing the coating to withstand deformation caused by thermal expansion and contraction or external force impact during the use of cooking utensils.

[0074] It should be noted that polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, epoxy-modified polysiloxane and amino-modified polysiloxane are all existing products, and the present invention does not specifically limit their structures.

[0075] According to some embodiments of the present invention, the co-solvent includes at least one of an alcohol solvent and an ether solvent.

[0076] The role of cosolvent in coatings is to assist film formation and participate in adjusting the wetting and leveling properties of the coating.

[0077] Alcohol solvents and ether solvents can reduce the viscosity of the film-forming material siloxane, making it easier for siloxane to flow and spread. Siloxane solutions with lower viscosity can be more evenly distributed on the surface of the substrate, which is conducive to the formation of a continuous and uniform film.

[0078] According to some embodiments of the present invention, the co-solvent includes at least one of methanol, ethanol, isopropanol, propylene glycol methyl ether, and ethylene glycol butyl ether.

[0079] According to some embodiments of the present invention, the acid catalyst includes at least one of formic acid, acetic acid, p-toluenesulfonic acid, hydrochloric acid, sulfuric acid, and nitric acid.

[0080] Acid catalysts are used to catalyze the hydrolysis and condensation reactions between silica sol, siloxane, zwitterionic sulfobetaine silane, and polysiloxane. In the hydrolysis reaction, the hydrogen ions in the acid can interact with the oxygen atoms in the silicon-oxygen bond, causing the electron cloud of the silicon-oxygen bond to shift toward the oxygen atom, thereby increasing the positive charge of the silicon atom. This polarization effect makes the silicon-oxygen bond more susceptible to attack by water molecules, reduces the activation energy of the hydrolysis reaction, and accelerates the rate of the hydrolysis reaction. In addition, the acid can combine with the silanol intermediates produced during the hydrolysis process through hydrogen bonds, making them more stable, preventing them from re-condensing or decomposing, and facilitating the further progress of the hydrolysis reaction.

[0081] In the condensation reaction, the acid can protonate the oxygen atom in the silanol group (Si-OH) to form Si-OH2 + This protonated silanol group has higher reactivity and is more likely to undergo nucleophilic substitution reactions with other silanol groups or oxygen atoms in siloxane molecules to form siloxane bonds (Si-O-Si).

[0082] According to some embodiments of the present invention, the antimicrobial coating further comprises a pigment dispersion, wherein the pigment dispersion comprises a pigment, a dispersant, a defoaming agent, a pH regulator, a thickener and water.

[0083] The addition of pigments can provide a variety of color options for coatings, and pigments can also work together with other components in the coating to improve the hiding power of the coating. Dispersants can evenly disperse pigment particles in the coating system and prevent particles from aggregating again, thereby improving the uniformity and stability of the coating.

[0084] According to some embodiments of the present invention, the pigment includes at least one of copper chrome black, iron manganese black, titanium dioxide, cobalt blue, cobalt green, cobalt black, titanium chrome brown, iron oxide red, iron oxide yellow, bismuth vanadate, and nickel titanium yellow; and / or the dispersant includes at least one of BYK-191 and DISPERBYK-101N; and / or the defoamer includes at least one of BYK1709, BYK088, and BYK024; and / or the pH adjuster includes at least one of hydrochloric acid, acetic acid, sodium hydroxide, and sodium bicarbonate; and / or the thickener includes at least one of bentonite, fumed silica, and BYK410.

[0085] BYK-191 and DISPERBYK-101N dispersants can deflocculate pigment particles through steric hindrance. Since the deflocculated toner particles are very small, a high-gloss, high-color-intensity coating can be obtained, while also increasing the transparency and hiding power of the coating. BYK-191 and DISPERBYK-101N are both existing products and were purchased.

[0086] In some embodiments, the antibacterial coating may also be added with at least one of a film-forming aid, an antifreeze agent, a filler, a leveling agent, a rheology regulator, a preservative, a UV absorber, an antioxidant, a matting agent, a lubricant, and a vulcanizer as needed, and the present invention does not make specific limitations.

[0087] According to some embodiments of the present invention, the present invention further provides an antibacterial cookware 100, referring to Figure 1 and 2 As shown, it includes a pot body 11 and an antibacterial coating 12, the antibacterial coating 12 is arranged on the inner surface of at least a portion of the pot body 11, the antibacterial coating 12 includes an antibacterial surface layer 121, the antibacterial surface layer 121 is formed by any of the above-mentioned antibacterial coatings, the antibacterial surface layer 121 includes antibacterial segments and siloxane groups, the interior of the antibacterial coating 12 and / or at least a portion of the surface away from the pot body 11 has a low surface energy segment; wherein the antibacterial segment is grafted to the low surface energy segment through the siloxane group.

[0088] The antibacterial coating 12 is provided on at least a portion of the inner surface of the pot body 11, which means that the antibacterial coating 12 can cover the entire inner surface of the pot body 11, or can be provided only on the inner surface of a portion such as the bottom of the pot.

[0089] The antibacterial coating 12 includes antibacterial segments, siloxane groups and low surface energy segments. Among them, the antibacterial segments refer to molecular chains with antibacterial properties, and the antibacterial segments give the antibacterial coating 12 antibacterial properties. The low surface energy segments refer to molecular chains with lower surface energy. When the low surface energy segments come into contact with other substances, they tend to reduce the surface energy to achieve a more stable state, and have a hydrophobic and non-sticky effect, that is, the low surface energy segments have low adhesion to other substances. Therefore, the low surface energy segments give the antibacterial coating 12 non-stick properties.

[0090] The antibacterial segment and the low surface energy segment are connected by grafting of siloxane groups, which means that the antibacterial segment and the low surface energy segment are connected by silicon-oxygen-silicon bonds (Si-O-Si bonds), thereby fixing the antibacterial segment and the low surface energy segment in the antibacterial coating 12, so that the antibacterial coating 12 has long-lasting antibacterial and non-stick properties. Siloxane is a class of compounds mainly composed of Si-O-Si bonds, with various structures, including chain and ring forms, and Si-O-Si bonds are hydrophobic groups, which themselves have good non-stick properties. ‌

[0091] In addition, due to the bonding effect of Si-O-Si bonds, the antibacterial segments and the low surface energy segments are grafted in the same group at the same time and are evenly distributed on the coating surface, avoiding the situation where the antibacterial ions are affected by the preparation process and ion agglomeration occurs, resulting in uneven distribution of surface antibacterial properties.

[0092] According to some embodiments of the present invention, further reference is made to Figure 2 As shown, the antibacterial coating 12 also includes a non-stick bottom layer 122, which is arranged between the antibacterial surface layer 121 and the inner surface of the pot body 11; wherein at least part of the surface of the antibacterial surface layer 121 includes antibacterial segments, and the antibacterial segments include zwitterionic sulfonyl betaine silane segments.

[0093] The antibacterial coating 12 further includes the non-stick bottom layer 122 , which means that the antibacterial coating 12 can be formed only by the antibacterial surface layer 121 , or can be formed by a combination of the antibacterial surface layer 121 and the non-stick bottom layer 122 .

[0094] The zwitterionic sulfobetaine silane segment refers to a molecular chain with a zwitterionic betaine structure. The zwitterionic betaine structure includes a cationic group and an anionic group. The cationic group will electrostatically attract the anionic phospholipid head on the cell membrane, and the anionic group will also interact with the cationic components on the cell membrane, thereby disrupting the normal structure and function of the cell membrane, increasing the permeability of the cell membrane, causing the leakage of substances in the cell, and ultimately causing the death of bacteria. That is, the zwitterionic betaine structure can destroy the bacterial cell membrane structure through electrostatic adsorption, thereby achieving the purpose of sterilization and antibacterial. In addition, the zwitterionic betaine structure has a strong hydrophilicity and forms a highly hydrated layer on the surface of the bacteria. This hydrated layer can prevent the bacteria from contacting and exchanging with nutrients, water, etc. in the surrounding environment. At the same time, the presence of the hydrated layer can also hinder the mutual aggregation and adhesion between bacteria, reduce the formation of bacterial biofilms, and make bacteria more susceptible to the influence of the external environment and the attack of the immune system. That is, the zwitterionic betaine structure can inhibit the formation of biofilms and hinder bacterial adhesion, thereby achieving an antibacterial effect.

[0095] The antibacterial segments including zwitterionic sulfonyl betaine silane segments can be characterized by nuclear magnetic resonance hydrogen spectrum, infrared spectrum, mass spectrum and other detection methods. In some embodiments, a portion of the antibacterial surface layer sample can be taken, ground into powder, and then the nuclear magnetic resonance hydrogen spectrum can be measured to characterize the presence of zwitterionic sulfonyl betaine silane segments in the antibacterial coating.

[0096] According to some embodiments of the present invention, the low surface energy segment includes a first low surface energy segment and a second low surface energy segment, the first low surface energy segment is arranged on the surface of the non-stick bottom layer 122 facing the antibacterial surface layer 121, and the second low surface energy segment is arranged on the surface of the antibacterial surface layer 121 facing the non-stick bottom layer 122, wherein the second low surface energy segment is grafted to the first low surface energy segment through a siloxane group.

[0097] by Figure 2 For example, the surface of the non-stick bottom layer 122 facing the antibacterial surface layer 121 with the first low surface energy segment refers to the inner surface of the non-stick bottom layer 122 with the first low surface energy segment, that is, the inner surface of the non-stick bottom layer 122 has non-stick properties; the surface of the antibacterial surface layer 121 facing the non-stick bottom layer 122 with the second low surface energy segment refers to the outer surface of the antibacterial surface layer 121 with the second low surface energy segment, that is, the outer surface of the antibacterial surface layer 121 has non-stick properties, so that even if the antibacterial surface layer 121 is scraped off to expose the non-stick bottom layer 122, it still has non-stick properties.

[0098] The second low surface energy segment is grafted and connected to the first low surface energy segment through the siloxane group, that is, the low surface energy segments between the antibacterial surface layer 121 and the non-stick bottom layer 122 are connected together through the siloxane group, so that a multi-dimensional siloxane group structure can be formed, which greatly improves the bonding force between the surface layer and the bottom layer, reduces the delamination and falling off of the antibacterial surface layer 121, and also improves the non-stick performance.

[0099] According to some embodiments of the present invention, the low surface energy segment has a polysiloxane group, and the polysiloxane group includes at least one of polydimethylsiloxane, polymethylphenylsiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, epoxy-modified polysiloxane, and amino-modified polysiloxane.

[0100] The main chain of polysiloxane is composed of silicon-oxygen bonds, which have a high bond energy and a relatively flexible molecular chain. At the same time, the organic groups (such as methyl) attached to the silicon atoms give the polysiloxane molecules a lower surface energy, making the coating surface less likely to be wetted by other substances.

[0101] According to some embodiments of the present invention, the non-stick bottom layer includes the following raw materials in mass fractions: 20%-30% siloxane, 18%-27% silica sol, 1%-5% polysiloxane, 1%-10% co-solvent, and the balance is water.

[0102] Both the non-stick bottom layer 122 and the antibacterial surface layer 121 include siloxane and polysiloxane, which helps to form Si-O-Si bonds at the bonding surface of the non-stick bottom layer 122 and the antibacterial surface layer 121, and form a multi-dimensional network bond between the two layers through chemical bonding (a chain, ring, or two-dimensional or three-dimensional structural formula of siloxane groups can be formed), thereby helping to improve the bonding force between the non-stick bottom layer 122 and the antibacterial surface layer 121 and the stability of the coating.

[0103] According to some embodiments of the present invention, the thickness of the non-stick bottom layer 122 is 15 μm-25 μm, and the thickness of the antibacterial surface layer 121 is 5 μm-15 μm.

[0104] The thickness of the non-stick bottom layer 122 and the antibacterial surface layer 121 can be measured by observing the cross section of the antibacterial coating 12 under an electron microscope (such as a scanning electron microscope). Exemplarily, the thickness of the non-stick bottom layer 122 can be 15μm, 16μm, 17μm, 18μm, 19μm, 20μm, 21μm, 22μm, 23μm, 24μm or 25μm. When the thickness of the non-stick bottom layer 122 is between 15μm and 25μm, the connection strength between the pot body 11 and the antibacterial surface layer 121 can be improved. The thickness of the antibacterial surface layer 121 can be 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm or 15μm, which can not only meet the antibacterial requirements, but also reduce the risk of delamination and falling off of the antibacterial surface layer 121 due to being too thick, and the antibacterial surface layer 121 of this thickness can withstand a certain degree of mechanical wear.

[0105] According to some embodiments of the present invention, the surface hardness of the antimicrobial coating 12 is 6H-9H.

[0106] The surface hardness of 6H-9H refers to the hardness value obtained by a pencil hardness test. The test method includes: using a pencil with a known hardness number to perform a scratch test on the surface of the antibacterial coating 12, and judging the hardness of the coating by the difficulty of the scratch. The pencil hardness is divided into 13 levels from 6H to 6B, where H represents hardness and B represents blackness. The larger the number, the higher the hardness.

[0107] The surface hardness of the antibacterial coating 12 is 6H-9H, which means that the antibacterial coating of the present invention has a relatively high hardness, is not easy to be scratched, and is scratch-resistant and durable.

[0108] According to some embodiments of the present invention, the structural formula of the segment formed by the antibacterial segment, the siloxane group and the low surface energy segment is as shown in formula (III): Formula (III), Among them, R 1 Including one of hydrogen, amino, mercapto, glycidyloxy, chloro, R 3It includes one of a methylene group, a secondary amine group, and an amine ester group, wherein m is 1 or 3, and n is 1, 2 or 3.

[0109] According to some embodiments of the present invention, reference Figure 1 and 2 As shown, the pot body 11 is a metal pot body, and the pot body 11 includes a pot side wall 111 and a pot bottom surface 112 which is concave on the inner surface, wherein the inner surface of the pot side wall 111 and / or the pot bottom surface 112 is provided with an antibacterial coating 12, and at least part of the surface of the antibacterial coating 12 forms a plurality of protrusions.

[0110] The surface of the metal pot body is hydrophilic, so the surface of the metal pot body generally includes hydroxyl groups, and the non-stick bottom layer 122 includes silanol groups. Dehydration condensation between silanol groups and hydroxyl groups can improve the bonding force between the non-stick bottom layer 122 and the pot body 11.

[0111] The formation of multiple protrusions on at least part of the surface of the antibacterial coating 12 means that at least part of the inner surface of the pot side wall 111 and / or the pot bottom surface 112 is provided with protrusions, and the antibacterial coating 12 is arranged according to the shape of the pot surface, so that the antibacterial coating 12 shows a protrusion structure. Arranging multiple protrusions on at least part of the inner surface of the pot side wall 111 and / or the pot bottom surface 112 can increase the rough surface, improve the non-stick performance and wear resistance. The antibacterial coating 12 will be arranged according to the shape of the pot surface, and will not affect the wear and corrosion resistance of the pot body 11 itself, thereby ensuring long-term antibacterial and non-stick properties.

[0112] According to some embodiments of the present invention, the present invention also provides a method for preparing an antibacterial cookware, comprising: providing a cookware body; coating any of the above-mentioned antibacterial coatings on the inner surface of at least a portion of the cookware body; drying the cookware body coated with the antibacterial coating at 120°C-170°C for 3min-10min, and then curing it at 250°C-300°C for 10min-25min to obtain the antibacterial cookware.

[0113] The pot body can be a frying pan, a frying pan, a soup pot, an inner pot of an electric rice cooker, and the like, and the coating method can be spraying, roller coating, flow coating, or brush coating, which is not specifically limited in the present invention.

[0114] The pot body coated with antibacterial coating is dried at 120℃-170℃ for 3min-10min. On the one hand, the solvent in the coating can be evaporated slowly. This slow evaporation process can make the coating flow better and reduce the problem of surface unevenness caused by rapid evaporation of the solvent, such as orange peel phenomenon. On the other hand, during the low-temperature surface drying process, the coating can better penetrate into the microscopic pores of the pot body or react with the active groups on the surface of the pot body to form chemical bonds or physical adsorption, which helps to improve the adhesion of the coating. Exemplarily, the surface drying temperature can be 120℃, 125℃, 130℃, 135℃, 140℃, 145℃, 150℃, 155℃, 160℃ or 170℃; the surface drying time can be 3min, 4min, 5min, 6min, 7min, 8min, 9min or 10min.

[0115] Curing at 250°C-300°C for 10min-25min, the components in the coating can undergo a cross-linking reaction, thereby making the internal structure of the antibacterial coating more compact, thereby helping to enhance the hardness, toughness and corrosion resistance of the antibacterial coating. Exemplarily, the curing temperature can be 250°C, 255°C, 260°C, 265°C, 270°C, 275°C, 280°C, 285°C, 290°C, 295°C or 300°C; the curing time can be 10min, 12min, 15min, 18min, 20min, 22min or 25min.

[0116] According to some embodiments of the present invention, providing the pot body includes: cleaning, degreasing and / or sandblasting the surface of the pot body, and then heating the pot body to 40°C-50°C.

[0117] The cleaning and degreasing of the pot body can be plasma cleaning or alkaline solution cleaning or organic solvent cleaning. The alkaline solution is generally sodium hydroxide solution or sodium carbonate solution; the organic solvent can be gasoline, kerosene, trichloroethylene, etc. The sandblasting treatment of the pot body is to obtain a substrate surface with a certain roughness to improve the bonding strength between the antibacterial coating and the pot body. The specific operation of the sandblasting treatment is not specifically limited by the present invention, and the treatment can be carried out by methods known in the art.

[0118] Heat the pot to 40℃-50℃, so that when the paint comes into contact with the pot, the viscosity of the paint decreases and it is easy to flow, so that it can be evenly spread on the surface of the pot, which helps to obtain a more uniform antibacterial coating.

[0119] According to some embodiments of the present invention, coating any of the above-mentioned antibacterial coatings on at least a portion of the inner surface of the pot body includes: providing a non-stick coating, the non-stick coating including the following raw materials in mass fractions: 20%-30% siloxane, 18%-27% silica sol, 1%-5% polysiloxane, 1%-10% co-solvent, and the balance being water; coating the non-stick coating on at least a portion of the inner surface of the pot body, drying the pot body coated with the non-stick coating at 120°C-170°C for 3min-10min, and then curing it at 250°C-300°C for 10min-25min to obtain a non-stick base layer; coating the antibacterial coating on at least a portion of the surface of the non-stick base layer.

[0120] The following describes the invention in conjunction with specific embodiments.

[0121] Example 1 An antibacterial coating includes the following raw materials in parts by weight based on 100 parts by weight of the total antibacterial coating: 25 parts by weight of methyltrimethoxysilane, 20 parts by weight of silica sol, 5 parts by weight of isopropanol, 2 parts by weight of N,N-dimethylaminopropylaminemethyltriethoxysilanesulfonic acid inner salt, 2 parts by weight of polydimethylsiloxane, 0.2 parts by weight of formic acid, and 45.8 parts by weight of water. The above raw materials are mixed and stirred for 4 hours to obtain the antibacterial coating.

[0122] The solid content of the silica sol is 40%, the pH of the silica sol is 9, the particle size Dv50 of the silica sol is 20 nm, and the number average molecular weight of the polydimethylsiloxane is 10,000.

[0123] The preparation method of the antibacterial cookware comprises: The surface of the aluminum pot is cleaned and degreased, then the aluminum pot is preheated to 45°C, and a 10μm thick antibacterial coating is sprayed on the surface of the aluminum pot; then, it is dried at 150°C for 5 minutes, and then cured at 280°C for 15 minutes to obtain the antibacterial pot.

[0124] Example 2 Different from Example 1, in this example, the amount of N,N-dimethylaminopropylamine methyltriethoxysilane sulfonic acid inner salt added is 1 part, and the amount of water added is 46.8.

[0125] Example 3 Different from Example 1, in this example, the amount of N,N-dimethylaminopropylamine methyltriethoxysilane sulfonic acid inner salt added is 5 parts, and the amount of water added is 42.8.

[0126] Example 4 Different from Example 1, the antibacterial agent in this example is N,N-dimethylaminoethylcarbamate propyltriethoxysilane sulfonic acid inner salt.

[0127] Example 5 Different from Example 1, the antibacterial agent in this example is 3-[dimethyl(3-(trimethoxysilyl)propylamino)]propane-1-sulfonate.

[0128] Example 6 Different from Example 1, the thickness of the antibacterial coating in this example is 5 μm.

[0129] Example 7 Different from Example 1, the thickness of the antibacterial coating in this example is 15 μm.

[0130] Comparative Example 1 Different from Example 1, the coating of this comparative example does not add an antibacterial agent, that is, the coating of this comparative example includes the following raw materials in parts by weight: 25 parts of methyltrimethoxysilane, 20 parts of silica sol, 5 parts of isopropanol, 2 parts of polydimethylsiloxane, 0.2 parts of formic acid, and 46.8 parts of water.

[0131] Comparative Example 2 Different from Example 1, the coating of this comparative example does not add polysiloxane, that is, the coating of this comparative example includes the following raw materials in parts by weight: 25 parts of methyltrimethoxysilane, 20 parts of silica sol, 5 parts of isopropanol, 2 parts of N,N-dimethylaminopropylaminemethyltriethoxysilane sulfonic acid salt, 0.2 parts of formic acid, and 46.8 parts of water.

[0132] Comparative Example 3 Different from Example 1, in this comparative example, the amount of N,N-dimethylaminopropylamine methyltriethoxysilane sulfonic acid inner salt added is 10 parts, and the amount of water added is 36.8.

[0133] Comparative Example 4 Different from Example 1, the antibacterial agent in this comparative example is a silver ion antibacterial agent, that is, the coating of this comparative example includes the following raw materials in parts by weight: 25 parts of methyltrimethoxysilane, 20 parts of silica sol, 5 parts of isopropanol, 2 parts of silver ion antibacterial agent, 2 parts of polydimethylsiloxane, 0.2 parts of formic acid, and 44.8 parts of water.

[0134] Comparative Example 5 Different from Example 1, the zwitterionic sulfobetaine in this comparative example has no siloxane group (i.e., no Si-O-Si bond), and its chemical structure is: .

[0135] Performance Testing Fried egg non-stick test: refer to the standard GB / T 32095.1~3-2015 "Household Food Metal Cooking Utensils Non-stick Surface Performance and Test Specification", wipe the coating surface of the sample with a soft cloth with vegetable oil, wash it with warm water above 60℃ and detergent, and then fry the egg after drying. Heat the cooking utensils on an electric stove with a rated voltage of 220 V and an output power of 1kW, and measure it with a surface thermometer with an accuracy of not less than 2.5. When the surface temperature of the inner coating reaches 140℃-170℃, break a fresh egg that meets the requirements of SB / T 10277 standard level 2 (weight 50g-60g) and put it into the cooking utensils, and wait until the egg white is basically coagulated (during the entire cooking process, the surface temperature of the inner coating shall not exceed 210℃); use a non-metallic spatula to remove the egg without damage. If it cannot be removed without damage, the residue can be removed by wiping it with a wet sponge or rag. The non-stickiness level is evaluated by the number of times the egg is fried.

[0136] Antibacterial property: refer to the standard GB / T 21866-2008 "Determination of antibacterial property and antibacterial effect of antibacterial coatings (paint films)", take 0.4mL-0.5mL of test bacterial solution and drop it on the negative control sample (A), blank control sample (B) and antibacterial coating sample (C). Use sterile tweezers to pick up the sterile covering film and cover it on samples (A), (B) and (C) respectively. Make sure to spread it flat and without bubbles so that the bacteria can evenly contact the sample, then place it in a sterile plate and culture it at (37±1)℃ and relative humidity RH>90% for 24h. Perform 3 parallel tests for each sample. Take out the samples cultured for 24 hours, add 20 mL of washing solution respectively, repeatedly wash sample (A), sample (B), sample (C) and the covering film (it is best to use tweezers to pick up the film and rinse), and after thorough washing, take the washing solution and inoculate it into nutrient agar medium (NA). After culturing at (37±1)℃ for 24 hours, count the live bacteria and determine the number of live bacteria in the washing solution according to the method of GB / T4789.2.

[0137] Long-lasting antibacterial properties The test plate was placed in water and boiled for 50 hours, and then the antibacterial property of the test plate was tested according to the standard GB / T 21866-2008 "Determination of antibacterial properties and antibacterial effects of antibacterial coatings (paint films)".

[0138] Test Results The tests in Examples 1-7 and Comparative Examples 1-5 are shown in Table 1.

[0139] Table 1 Properties of coatings in Examples 1-7 and Comparative Examples 1-5

[0140] It can be seen from Table 1 that the antibacterial property and the lasting antibacterial property of the antibacterial coating in the embodiment of the present invention are much higher than those of the blank group (without adding antibacterial agent) in Comparative Example 1, indicating that the zwitterionic sulfobetaine silane of the present invention has excellent antibacterial property.

[0141] It can be seen from Examples 1-3 and Comparative Example 3 that the greater the amount of zwitterionic sulfobetaine silane added, the better the antibacterial effect of the coating, but the non-stick performance will decrease. When the amount of zwitterionic sulfobetaine silane added is 10%, the non-stickiness of the coating will be 20 times. Therefore, in order to take into account both antibacterial and non-stick properties, the amount of zwitterionic sulfobetaine silane added needs to be controlled below 5%, so that good antibacterial performance can be achieved while meeting the non-stickiness requirements.

[0142] It can be seen from Examples 1, 6-7 that when the thickness of the antibacterial coating increases, the antibacterial property and the lasting antibacterial property are not significantly affected, but the non-stick property increases accordingly. Therefore, when the thickness of the antibacterial coating is between 5 μm and 15 μm, good non-stick property and lasting antibacterial property can be ensured.

[0143] Compared with Comparative Example 2, the non-stickiness of the fried egg in the antibacterial coating without adding polysiloxane in Comparative Example 2 is 10 times (i.e., the egg will stick to the pan after frying 10 times in a row), while the non-stickiness of the fried egg in Example 1 of the present invention is 310 times, indicating that the addition of polysiloxane can significantly improve the non-stickiness of the coating.

[0144] Compared with Comparative Example 4, the durable antibacterial property of the antibacterial coating in the embodiment of the present invention is much higher than that of the antibacterial coating in Comparative Example 4 to which a silver ion antibacterial agent is added, and the non-stick property is better. Compared with Comparative Example 5, the durable antibacterial property of the antibacterial coating in the embodiment of the present invention is much higher than that of the antibacterial coating of the zwitterionic sulfonate betaine silane without siloxane groups in Comparative Example 5, and the non-stick property is equivalent. This shows that the zwitterionic sulfonate betaine silane of the present invention can react with silica sol, polysiloxane and siloxane through hydroxyl dehydration condensation, and the zwitterionic sulfonate betaine silane chain segments are fixed in the coating through chemical bonds, thereby obtaining a durable and efficient antibacterial effect.

[0145] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification under the technical concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An antibacterial coating, characterized in that: The raw materials include the following mass fractions: Siloxane 20%-30%, silica sol 18%-27%, zwitterionic sulfobetaine silane 1%-5%, cosolvent 1%-10%, polysiloxane 1%-5%, acid catalyst 0.1%-0.5%, and the balance is water.

2. The antibacterial coating according to claim 1, characterized in that: The structural formula of the siloxane is shown in formula (I): Formula (I), Among them, R 1 Including one of hydrogen, amino, mercapto, glycidyloxy, chloro, R 2 It includes one of methyl and ethyl, and m is 1 or 3.

3. The antibacterial coating according to claim 2, characterized in that: The siloxane includes at least one of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, chloropropyltrimethoxysilane and chloropropyltriethoxysilane.

4. The antibacterial coating according to claim 1, characterized in that: The structural formula of the zwitterionic sulfobetaine silane is shown in formula (II): Formula (II), Among them, R 2 Including one of methyl and ethyl, R 3 It includes one of a methylene group, a secondary amine group, and an amine ester group, wherein m is 1 or 3, and n is 1, 2 or 3.

5. The antibacterial coating according to claim 4, characterized in that: The zwitterionic sulfobetaine silane includes at least one of N,N-dimethylaminoethylcarbamate propyltriethoxysilane sulfonic acid inner salt, N,N-dimethylaminopropylaminomethyltriethoxysilane sulfonic acid inner salt, and 3-[dimethyl(3-(trimethoxysilyl)propylamino)]propane-1-sulfonate.

6. The antibacterial coating according to claim 1, characterized in that: The solid content of the silica sol is 30%-50%; and / or, The pH of the silica sol is 8-10; and / or, The particle size D of the silica sol V 50 is 10nm-100nm.

7. The antibacterial coating according to claim 1, characterized in that: The number average molecular weight of the polysiloxane is 1,000-100,000.

8. The antibacterial coating according to claim 7, characterized in that: The polysiloxane includes at least one of polydimethylsiloxane, polymethylphenylsiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, epoxy-modified polysiloxane and amino-modified polysiloxane.

9. The antibacterial coating according to claim 1, characterized in that: The auxiliary solvent includes at least one of an alcohol solvent and an ether solvent.

10. The antibacterial coating according to claim 9, characterized in that: The co-solvent includes at least one of methanol, ethanol, isopropanol, propylene glycol methyl ether, and ethylene glycol butyl ether.

11. The antibacterial coating according to claim 1, characterized in that: The acid catalyst includes at least one of formic acid, acetic acid, p-toluenesulfonic acid, hydrochloric acid, sulfuric acid, and nitric acid.

12. The antimicrobial coating according to any one of claims 1 to 11, characterized in that: The antimicrobial coating further comprises a pigment dispersion, which comprises a pigment, a dispersant, a defoaming agent, a pH adjuster, a thickener and water.

13. The antimicrobial coating according to claim 12, characterized in that: The pigment comprises at least one of copper chrome black, iron manganese black, titanium dioxide, cobalt blue, cobalt green, cobalt black, titanium chrome brown, iron oxide red, iron oxide yellow, bismuth vanadate, and nickel titanium yellow; and / or, The dispersant comprises at least one of BYK-191 and DISPERBYK-101N; and / or, The defoaming agent comprises at least one of BYK1709, BYK088 and BYK024; and / or, The pH adjuster includes at least one of hydrochloric acid, acetic acid, sodium hydroxide and sodium bicarbonate; and / or, The thickener includes at least one of bentonite, fumed silica and BYK410.

14. An antibacterial cookware, characterized in that: include: Pot body; An antibacterial coating, the antibacterial coating being arranged on the inner surface of at least a portion of the pot body, the antibacterial coating comprising an antibacterial surface layer, the antibacterial surface layer being formed by the antibacterial coating according to any one of claims 1 to 13, the antibacterial surface layer comprising antibacterial segments and siloxane groups, and the interior of the antibacterial coating and / or at least a portion of the surface away from the pot body having low surface energy segments; Wherein, the antibacterial segment is grafted and connected to the low surface energy segment through the siloxane group.

15. The antibacterial cookware according to claim 14, characterized in that: The antimicrobial coating further comprises: A non-stick bottom layer, the non-stick bottom layer is arranged between the antibacterial surface layer and the inner surface of the pot body; Wherein, at least part of the surface of the antibacterial surface layer comprises the antibacterial segment, and the antibacterial segment comprises a zwitterionic sulfobetaine silane segment.

16. The antibacterial cookware according to claim 15, characterized in that: The low surface energy segments include: A first low surface energy segment, wherein the first low surface energy segment is disposed on a surface of the non-stick bottom layer facing the antibacterial surface layer; A second low surface energy segment, wherein the second low surface energy segment is disposed on a surface of the antibacterial surface layer facing the non-stick bottom layer; Wherein, the second low surface energy segment is grafted and connected to the first low surface energy segment through the siloxane group.

17. The antibacterial cookware according to claim 14, characterized in that: The low surface energy segment has a polysiloxane group, and the polysiloxane group includes at least one of polydimethylsiloxane, polymethylphenylsiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, epoxy-modified polysiloxane, and amino-modified polysiloxane.

18. The antibacterial cookware according to claim 15, characterized in that: The non-stick bottom layer comprises the following raw materials in mass fractions: 20%-30% siloxane, 18%-27% silica sol, 1%-5% polysiloxane, 1%-10% co-solvent, and the balance is water.

19. The antibacterial cookware according to claim 15, characterized in that: The thickness of the non-stick bottom layer is 15 μm-25 μm, and the thickness of the antibacterial surface layer is 5 μm-15 μm.

20. The antibacterial cookware according to claim 14, characterized in that: The surface hardness of the antibacterial coating is 6H-9H.

21. The antibacterial cookware according to any one of claims 14 to 20, characterized in that: The structural formula of the chain segment formed by the antibacterial chain segment, the siloxane group and the low surface energy chain segment is shown in formula (III): Formula (III), Among them, R 1 Including one of hydrogen, amino, mercapto, glycidyloxy, chloro, R 3 It includes one of a methylene group, a secondary amine group, and an amine ester group, wherein m is 1 or 3, and n is 1, 2 or 3.

22. The antibacterial cookware according to any one of claims 14 to 20, characterized in that: The pot body is a metal pot body, and the pot body includes a pot side wall and a pot bottom surface that is concave on the inner surface, wherein the inner surface of the pot side wall and / or the pot bottom surface is provided with the antibacterial coating, and at least part of the surface of the antibacterial coating forms a plurality of protrusions.

23. A method for preparing an antibacterial cookware, characterized in that: include: Providing a pot body; Applying the antibacterial coating according to any one of claims 1 to 13 on the inner surface of at least a portion of the pot body; The antibacterial cookware can be obtained by drying the pot body coated with the antibacterial coating at 120° C.-170° C. for 3 min-10 min, and then curing at 250° C.-300° C. for 10 min-25 min.

24. The method for preparing the antibacterial cookware according to claim 23, characterized in that: The pot body provided comprises: The surface of the pot body is cleaned, degreased and / or sandblasted, and then the pot body is heated to 40° C.-50° C.

25. The method for preparing the antibacterial cookware according to claim 23, characterized in that: The step of applying the antibacterial coating according to any one of claims 1 to 13 on the inner surface of at least a portion of the pot body comprises: A non-stick coating is provided, wherein the non-stick coating comprises the following raw materials in mass fractions: 20%-30% siloxane, 18%-27% silica sol, 1%-5% polysiloxane, 1%-10% cosolvent, and the balance is water; The non-stick coating is applied on at least a portion of the inner surface of the pot body, the pot body coated with the non-stick coating is dried at 120° C.-170° C. for 3 min-10 min, and then cured at 250° C.-300° C. for 10 min-25 min to obtain a non-stick bottom layer; The antimicrobial coating is coated on at least a portion of the surface of the non-stick base layer.

Images