A self-cleaning tempered coated glass and its preparation method
By coating a self-cleaning coating slurry containing organosilicon oligomers and modified silica sol onto glass and then sintering it once, the problems of insufficient adhesion and poor hardness of self-cleaning glass coatings in industrial production are solved, achieving a self-cleaning effect with high adhesion and high hardness.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- KUNMING UNIV OF SCI & TECH
- Filing Date
- 2023-12-20
- Publication Date
- 2026-07-17
AI Technical Summary
Existing self-cleaning glass coatings suffer from insufficient adhesion and poor hardness in industrial production, resulting in unsatisfactory self-cleaning effects and easy wear during high-altitude cleaning operations.
A self-cleaning coating slurry containing organosilicon oligomers with a polymerization degree not exceeding 200, nano-titanium dioxide slurry, modified silica sol, nitrates, and water-soluble organic matter is applied to glass by roller coating or spraying and then sintered once to form self-cleaning tempered coated glass.
It improves the adhesion and hardness of the coating to glass, enhances the self-cleaning effect, ensures effective removal of stains under natural conditions, and reduces the frequency and risk of manual cleaning.
Smart Images
Figure CN117735853B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of glass product technology, specifically relating to a self-cleaning tempered coated glass and its preparation method. Background Technology
[0002] In everyday buildings, whether commercial or residential, long-term use inevitably leads to the adsorption and deposition of air pollutants, such as dust and atmospheric organic pollutants, on the exterior surfaces of both ordinary and energy-saving glass. As these pollutants accumulate and form stubborn stains, the light transmittance of the glass surface continuously decreases, affecting the building's appearance. Residential buildings often ignore this issue due to cost considerations, while commercial high-rise buildings currently mostly address it through regular manual cleaning at height. However, this method continuously increases the building's maintenance costs and poses unnecessary risks to workers and their families during high-altitude cleaning operations.
[0003] To avoid or reduce the need for manual cleaning of architectural glass, the glass surface needs to possess self-cleaning and easy-to-clean properties. Currently, there are two main technical methods for achieving self-cleaning on glass surfaces: one is superhydrophobic self-cleaning technology. However, this type of hydrophobic surface continuously absorbs organic pollutants from the air and eventually loses its cleaning ability, so it is rarely used now. The other type of self-cleaning technology is hydrophilic self-cleaning technology using photocatalysis. Its principle lies in combining nano-photocatalysts, such as titanium dioxide, with porous silica nanofilms. Sunlight irradiation provides the photocatalyst with oxidative holes, transforming the silica surface into a hydrophilic surface with hydroxyl groups. This method, on the one hand, utilizes the surface's hydrophilicity to reduce the adhesion of organic pollutants. On the other hand, the photogenerated holes created by the film can directly degrade organic pollutants adhering to the surface. This glass surface, which inhibits the adhesion of organic pollutants using photocatalytic technology, can prevent the formation of stubborn stains, and at the same time, it can effectively remove dirt under natural rainwater washing.
[0004] In fact, photocatalysts alone cannot serve as self-cleaning coating materials because their surfaces lack superhydrophilicity, resulting in strong adhesion to stains in the absence of light and easy accumulation of dirt. Hydrophilic self-cleaning film technology for glass surfaces is primarily represented by nanofilms formed from nano-titanium dioxide and porous silica, as reported and proposed by S. Permpoon et al. These films utilize the hydrophilic surface of porous silica to reduce the water contact angle. Simultaneously, the photocatalytic effect of titanium dioxide generates photogenerated oxidation cavities, degrading organic matter while simultaneously forming numerous silanol groups on the silica surface, maintaining the material's hydrophilicity. This reduces contaminant adhesion, and under rain or external force, contaminants are easily removed due to the hydrophilicity of the glass surface. The combination of these two methods gives the material self-cleaning capabilities. The main method they used was as follows: They mixed the precursor containing nano-silica prepared by hydrolysis of tetraethyl orthosilicate with hydrothermally synthesized nano-titanium dioxide, applied it to the glass surface multiple times, and sintered it for up to 2 hours. The resulting film can give ordinary glass good light transmittance, hydrophilicity and self-cleaning properties.
[0005] However, the above-mentioned technical solutions have significant shortcomings for industrial production. First, the precursor containing nano-silica, prepared by hydrolysis of tetraethyl orthosilicate, has insufficient adhesion to glass. To ensure sufficient mechanical strength, the aforementioned films require a long sintering time. Furthermore, the sol-gel method solution suffers from insufficient stability due to continuous reaction, which is detrimental to industrial production. In recent years, through continuous process improvements, silica sol has been used instead of silicate ester hydrolysates to prepare self-cleaning glass. However, the insufficient adhesion between silica sol and glass leads to poor mechanical properties of these films, affecting the self-cleaning and easy-cleaning effects of the glass surface. Taking the national standard GBT37830-2019 for anti-fouling and easy-clean coated glass as an example, the hardness requirement for the self-cleaning film of this type of glass is only a pencil hardness of 3H. This level of film hardness has poor abrasion resistance and is very easily worn during production, transportation, handling, and manual cleaning. Summary of the Invention
[0006] In view of the shortcomings and deficiencies of the existing technology, the primary objective of this invention is to provide a self-cleaning tempered coated glass and its preparation method, which can effectively improve the adhesion between the coating and the glass, increase the hardness of the tempered glass, and enhance the cleaning effect of the self-cleaning coating.
[0007] To achieve the above-mentioned technical effects, the present invention is implemented through the following technical solution:
[0008] In a first aspect, a self-cleaning tempered coated glass is provided, comprising ordinary glass and a self-cleaning coating slurry, characterized in that a layer of self-cleaning coating slurry is rolled or sprayed onto an ordinary glass substrate and sintered in one step using a glass tempering process; the self-cleaning coating slurry, by weight percentage, comprises the following components: 5-20% organosilicon oligomer with a degree of polymerization not exceeding 200, 3-20% nano-titanium dioxide slurry, 1-20% modified silica sol, 0.1-1% nitrate, 10-40% water-soluble organic matter that can achieve complete miscibility and cross-linking with the organosilicon oligomer, 5-60% solvent, and 0-70% water; the modified silica sol is an organic carbon hydroxyl-modified silica sol with an average particle size not exceeding 25 nanometers; the nitrate is at least one selected from copper nitrate, iron nitrate, nickel nitrate, cerium nitrate, chromium nitrate, and silver nitrate; and the water-soluble organic matter is a pore-forming agent.
[0009] Furthermore, the organosilicon oligomer is at least one of methyl orthosilicate, ethyl orthosilicate, amino silicone oil, and γ-mercaptopropyltrimethoxysilane; the organosilicon oligomer has a weight percentage of 5-20%; and the degree of polymerization of the organosilicon oligomer is 5-200.
[0010] Furthermore, the nano-titanium dioxide slurry is one of the following: an aqueous slurry and a solvent-based slurry; the average particle size of the nano-titanium dioxide powder in the nano-titanium dioxide slurry does not exceed 25 nanometers.
[0011] Furthermore, the water-soluble organic compound is at least one of konjac glucomannan, water-soluble amino resin, water-soluble imino resin, and water-soluble carboxylic acid resin.
[0012] Furthermore, the solvent is at least one selected from methanol, ethanol, isopropanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, and ethyl acetate.
[0013] Secondly, a method for preparing self-cleaning tempered coated glass is provided, characterized by comprising the following preparation steps:
[0014] S1: Add organosilicon oligomer to nano-titanium dioxide slurry, then add water, solvent, modified silica sol, water-soluble organic matter and nitrate, stir for 10-30 minutes, disperse and stir evenly to form a self-cleaning coating slurry;
[0015] S2: Roll or spray a self-cleaning coating slurry onto the glass substrate and heat it at 160-280 degrees Celsius for 3-5 minutes to cure it;
[0016] S3: After curing, push it into the tempering furnace for tempering for 3-8 minutes to form self-cleaning tempered coated glass.
[0017] Furthermore, in S2, the final film thickness of the self-cleaning tempered glass is controlled between 100 and 300 nanometers.
[0018] The beneficial effects of this invention are:
[0019] 1. This invention selects organosilicon oligomers with a degree of polymerization of 5 to 200 as film-forming agents to improve the adhesion of the coating to glass and the strength of the film.
[0020] 2. The present invention uses water-soluble organic materials that can be completely miscible and cross-linked with organosilicon oligomers. During the film drying and sintering process, on the one hand, organosilicon oligomers and water-soluble organic materials as pore-forming agents undergo cross-linking reactions, and on the other hand, phase separation and aggregation of organic materials are avoided, reducing the pore size after sintering and improving the strength of the self-cleaning coating.
[0021] 3. The present invention uses modified silica sol, which can form a cross-linking reaction with organosilicon at high temperature, further improving the strength of the self-cleaning coating on the glass surface;
[0022] 4. The present invention selects nitrate precursors with co-catalytic function, such as copper nitrate, iron nitrate, nickel nitrate, cerium nitrate, chromium nitrate and silver nitrate. During high-temperature calcination, they form monomolecular oxides that adhere to the surface of nano-titanium dioxide, thereby enhancing the photocatalytic self-cleaning effect of the coating. Attached Figure Description
[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is a schematic diagram of the overall process of the present invention; Detailed Implementation
[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0026] Example 1:
[0027] See Figure 1As shown, a self-cleaning tempered coated glass and its preparation method are disclosed. The self-cleaning coating slurry formulation 1, by weight, comprises: 5% methyl orthosilicate with a degree of polymerization of 5, 5% ethyl orthosilicate with a degree of polymerization of 50, 4.9% nano-titanium dioxide slurry with a solid content of 30% (average particle size of 5 nm), 20% organic carbon hydroxyl-modified silica sol with an average particle size of 3 nm, 0.1% copper nitrate, 10% konjac glucomannan, 29.5% ethanol, 25% methanol, and 0.5% ethylene glycol monobutyl ether. The titanium dioxide nano-slurry is dispersed in a mixed solution of ethanol, methanol, and water for 10 minutes. Then, methyl orthosilicate, organic carbon hydroxyl-modified silica sol, ethyl orthosilicate, konjac glucomannan, ethylene glycol monobutyl ether, and copper nitrate are added sequentially and stirred until homogeneous before use.
[0028] The self-cleaning coating slurry of the above formulation was applied by roller coating, with the dry film thickness controlled at 150 nanometers. It cured at 200 degrees Celsius for 5 minutes and was tempered at 650 degrees Celsius for 5 minutes, at which point the film surface was sintered. The film was tested using the pencil test, showing a hardness of 6H and a hydrophilic angle of 5 degrees.
[0029] Example 2:
[0030] A self-cleaning tempered coated glass and its preparation method, wherein, by weight, the self-cleaning coating slurry formulation 2 comprises: 5% methyl orthosilicate with a degree of polymerization of 10, 5% amino silicone oil with a degree of polymerization of 50, 3% nano-titanium dioxide slurry with a solid content of 30% (average particle size of 5 nm), 1% organic carbon hydroxyl modified silica sol with an average particle size of 5 nm, 1% ferric nitrate, 5% Weng Kai'er CYMEL385-water-soluble amino resin, 5% water-soluble carboxyl resin, 70% water, and 5% isopropanol; the titanium dioxide nano-slurry is dispersed in a mixed solution of isopropanol and water for 10 minutes, and then methyl orthosilicate, amino silicone oil, organic carbon hydroxyl modified silica sol, and ferric nitrate are added sequentially and stirred evenly for later use.
[0031] The self-cleaning coating slurry of the above formulation was applied by roller coating, with the dry film thickness controlled at 120 nanometers. It cured at 200 degrees Celsius for 6 minutes and was tempered at 680 degrees Celsius for 3 minutes, at which point the film surface was sintered. The film was tested using the pencil test, showing a hardness of 7H and a hydrophilic angle of 10 degrees.
[0032] Example 3:
[0033] A self-cleaning tempered coated glass and its preparation method, wherein the self-cleaning coating slurry formulation 3, by weight, comprises: 5% orthosilicate with a degree of polymerization of 200, 15% γ-mercaptopropyltrimethoxysilane with a degree of polymerization of 50, 3% nano-titanium dioxide slurry with a solid content of 30% (average particle size of 15 nm), 3% organic carbon hydroxyl modified silica sol with an average particle size of 10 nm, 0.2% nickel nitrate, 0.3% chromium nitrate, 30% Weng Kai'er CYMEL385-water-soluble amino resin, 20% ethylene glycol, and 23.5% water; the nano-titanium dioxide slurry is dispersed in a mixed solution of ethylene glycol and water for 10 minutes, and then orthosilicate, γ-mercaptopropyltrimethoxysilane, organic carbon hydroxyl modified silica sol, Weng Kai'er CYMEL385-water-soluble amino resin, and nickel nitrate are added sequentially and stirred evenly for later use.
[0034] The self-cleaning coating slurry of the above formulation, applied by roller coating, achieved a dry film thickness of 120 nanometers. It cured at 180 degrees Celsius for 6 minutes and was tempered at 650 degrees Celsius for 5 minutes, at which point the film surface was sintered. The film, tested using the pencil test, showed a hardness of 7H or higher and a hydrophilic angle of 10 degrees.
[0035] Example 4:
[0036] A self-cleaning tempered coated glass and its preparation method, wherein the self-cleaning coating slurry formula 4, by weight, comprises: 5% amino silicone oil with a degree of polymerization of 200, 5% tetraethyl orthosilicate with a degree of polymerization of 200, 20% titanium dioxide nanoparticles (average particle size of 15 nm) slurry with a solid content of 30%, 20% organic carbon hydroxyl modified silica sol with a particle size of 10 nm, 0.5% silver nitrate, 5.5% konjac glucomannan, 14% water-soluble carboxylic acid resin, and 30% water; the nano-titanium dioxide slurry is dispersed in water for 10 minutes, and then amino silicone oil, organic carbon hydroxyl modified silica sol, konjac glucomannan, water-soluble carboxylic acid resin, and nickel nitrate are added sequentially and stirred evenly for later use.
[0037] The self-cleaning coating slurry of the above formulation, applied by roller coating, with a dry film thickness controlled at 200 nanometers, cured at 180 degrees Celsius for 6 minutes and tempered at 620 degrees Celsius for 10 minutes, achieving sintering of the film surface. The film, tested using the pencil test, showed a hardness of 7H and a hydrophilic angle of 5 degrees.
[0038] Example 5:
[0039] A self-cleaning tempered coated glass and its preparation method, wherein the self-cleaning coating slurry formulation 5, by weight, comprises: 5% γ-mercaptopropyltrimethoxysilane with a degree of polymerization of 200, 5% tetraethyl orthosilicate with a degree of polymerization of 200, 8% nano-titanium dioxide slurry with a solid content of 40% (average particle size of 25 nm), 20% organic carbon hydroxyl-modified silica sol with a particle size of 25 nm, 1% cerium nitrate, 10% konjac glucomannan, 5% water-soluble imino resin, 5% ethylene glycol monomethyl ether, and 42% water. The nano-titanium dioxide dispersion is dispersed in a mixed solution of water and ethylene glycol monomethyl ether for 10 minutes, and then γ-mercaptopropyltrimethoxysilane, tetraethyl orthosilicate, modified silica sol, konjac glucomannan, water-soluble carboxyl resin, water-soluble imino resin, and cerium nitrate are added sequentially and stirred evenly for later use.
[0040] The self-cleaning coating slurry of the above formulation, applied by roller coating, with a dry film thickness controlled at 300 nanometers, cured at 180 degrees Celsius for 6 minutes and tempered at 600 degrees Celsius for 15 minutes, allowing the film surface to be sintered. The film, tested using the pencil test, showed a hardness of 7H and a hydrophilic angle of 10 degrees.
[0041] Comparative Example 1:
[0042] The mixture consists of 20% nano-titanium dioxide slurry (particle size ≤ 20 nm) with a solid content of 10%, 30% tetraethyl orthosilicate, 1% 0.5M hydrochloric acid, 20% acid-modified silica sol with a solid content of 20% and a particle size of 10 nm, 15% polyethylene glycol, 9% ethanol, and 5% water. Tetraethyl orthosilicate is dissolved in ethanol and the titanium dioxide nano-slurry. Hydrochloric acid and water are added and the mixture is stirred for 5 hours. After standing for 10 hours, polyethylene glycol is added and stirred for 30 minutes. The mixture is then coated using a roller, with the dry film thickness controlled at 100 nm and 120 nm respectively.
[0043] The self-cleaning coating slurry of the above formulation was applied by roller coating, with a dry film thickness controlled at 120 nanometers. It cured at 180 degrees Celsius for 6 minutes and was tempered at 680 degrees Celsius for 30 minutes, achieving sintering of the film surface. The film, tested using the pencil test, showed a hardness of only 3H and a hydrophilic angle of 10 degrees. Compared to the examples, because no organosilicon oligomers, carbonyl-modified silica sol, or cross-linked resin were used as pore-forming agents, the films in the control examples, even after prolonged high-temperature sintering, still exhibited low film strength.
Claims
1. A self-cleaning tempered coated glass, comprising ordinary glass and a self-cleaning coating paste, characterized in that, A self-cleaning coating slurry is rolled or sprayed onto a regular glass substrate and then sintered in one step using a glass tempering process. The self-cleaning coating slurry, by weight percentage, comprises the following components: 5-20% organosilicon oligomer with a degree of polymerization not exceeding 200, 3-20% nano-titanium dioxide slurry, 1-20% modified silica sol, 0.1-1% nitrate, 10-40% water-soluble organic matter that can achieve complete miscibility and cross-linking with the organosilicon oligomer, 5-60% solvent, and 0-70% water. The modified silica sol is an organic carbon hydroxyl-modified silica sol with an average particle size not exceeding 25 nanometers. The nitrate is at least one of copper nitrate, iron nitrate, nickel nitrate, cerium nitrate, chromium nitrate, and silver nitrate. The water-soluble organic matter is a pore-forming agent.
2. The self-cleaning tempered coated glass according to claim 1, characterized in that, The organosilicon oligomer is at least one of methyl orthosilicate, ethyl orthosilicate, amino silicone oil, and γ-mercaptopropyltrimethoxysilane; the degree of polymerization of the organosilicon oligomer is 5 to 200.
3. The self-cleaning tempered coated glass according to claim 1, characterized in that, The nano-titanium dioxide slurry is one of the water-based slurry and the solvent-based slurry; the average particle size of the nano-titanium dioxide powder in the nano-titanium dioxide slurry does not exceed 25 nanometers.
4. The self-cleaning tempered coated glass according to claim 1, characterized in that, The water-soluble organic compound is at least one of konjac glucomannan, water-soluble amino resin, water-soluble imino resin, and water-soluble carboxylic acid resin.
5. The self-cleaning tempered coated glass according to claim 1, characterized in that, The solvent is at least one of methanol, ethanol, isopropanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, and ethyl acetate.
6. The method for preparing self-cleaning tempered coated glass according to any one of claims 1 to 5, characterized in that, The preparation steps include the following: S1: Add organosilicon oligomer to nano-titanium dioxide slurry, then add water, solvent, modified silica sol, water-soluble organic matter and nitrate, stir for 10-30 minutes, disperse and stir evenly to form a self-cleaning coating slurry; S2: Roll or spray a self-cleaning coating slurry onto the glass substrate and heat it at 160-280 degrees Celsius for 3-5 minutes to cure it; S3: After curing, push it into the tempering furnace for tempering for 3-8 minutes to form self-cleaning tempered coated glass.
7. The method for preparing self-cleaning tempered coated glass according to claim 6, characterized in that, In step S2, the final film thickness of the self-cleaning tempered glass is controlled between 100 and 300 nanometers.