CN110669362B

CN110669362B - Antireflection coating and preparation method and application thereof

Info

Publication number: CN110669362B
Application number: CN201910982340.1A
Authority: CN
Inventors: 韩超; 胡文杰; 陶玉溪
Original assignee: Ningbo Yong'an Guangke New Material Technology Co ltd
Current assignee: Ningbo Yong'an Guangke New Material Technology Co ltd
Priority date: 2019-10-16
Filing date: 2019-10-16
Publication date: 2021-11-23
Anticipated expiration: 2039-10-16
Also published as: CN110669362A

Abstract

The invention relates to a weather-resistant closed-cell antireflection coating and a preparation method and application thereof. The coating comprises the composite nano particles which are formed by coating spherical hyperbranched resin particles with silicon oxide with a network structure and have a core-shell structure, after the coating is formed on a substrate and is thermally cured, the core formed by hyperbranched resin in the composite nano particles can be burnt, hollow silicon oxide shells, namely the hollow nano particles and the pore structures (namely the gaps) among the hollow nano particles are left, and the gaps among the hollow nano particles on the surface of the coating are filled with silicon oxide to form a closed pore structure, so that the effect of improving the coating transmissivity and simultaneously increasing the coating weather resistance is achieved. The coating disclosed by the invention not only has an excellent anti-reflection function, but also has the remarkable advantages of simple process, high weather resistance, high cost performance and the like.

Description

Antireflection coating and preparation method and application thereof

Technical Field

The invention belongs to the technical field of coatings, and particularly relates to an antireflection coating as well as a preparation method and application thereof.

Background

The antireflection coating has very important application in the traditional optical industries such as optical lenses, laser devices and the like. In recent years, industries such as photovoltaic equipment, high-end display cabinets, display equipment and automobile glass have wide requirements on antireflection coatings, and the low refractive performance of the antireflection coatings (the coatings have certain porosity and pore structures after forming coatings and can directly reflect on the refractive performance) is utilized to reduce the light reflection rate of the surfaces of the equipment and improve the light transmittance.

At present, equipment for coating antireflection coatings is increasingly used in outdoor environments, such as photovoltaic glass, greenhouse glass, automobile glass and the like. In the traditional optical industry, the antireflection coating and the formed coating basically work in a closed environment, and the equipment of the industries is basically exposed to air and even used in an outdoor environment. This means that the coating inevitably comes into contact with contaminants. These contaminants not only adsorb on the surface of the coating but also enter the pores of the coating, block the pores, reduce the porosity of the coating, hinder the transmission of light, even corrode the substrate when in contact therewith, and thus reduce the performance of the device. In order not to affect the user experience and the performance of the equipment, it is necessary that the antireflective coating and the formed coating have good weatherability to contaminants.

To address the resistance to contaminants, it is common practice to prepare a layer of low surface energy material on the surface of the pores in the coating structure to reduce the adhesion of contaminants. There are three problems with this approach, first, the low surface energy materials are typically fluorine-containing materials, which present potential risks to both the human body and the environment; second, these low surface energy materials have a limited lifetime and are prone to failure, and third, they add one or more process steps and virtually increase manufacturing costs. Therefore, a new technical solution is needed to solve this problem.

Disclosure of Invention

In order to solve the problems, the invention provides a weather-resistant closed-cell antireflection coating, and a preparation method and application thereof, and the weather resistance of the antireflection coating can be effectively improved.

The invention provides an antireflection coating, which consists of a silicon source, hyperbranched resin, an auxiliary agent, a catalyst and a solvent, wherein the silicon source is alkoxy silane, the catalyst is acid, and the solvent is alcohol; the proportioning relation of each component is as follows by weight:

3% -5% of silicon source;

1-10% of hyperbranched resin;

and (3) 85-96% of auxiliary agent, catalyst and solvent.

In a preferred embodiment, the silicon source is Tetraethoxysilane (TEOS) and/or Tetramethoxysilane (TMOS).

In another preferred embodiment, the hyperbranched resin is an acrylate oligomer.

In another preferred embodiment, the catalyst is one or a combination of two of organic acid or inorganic acid.

In another preferred embodiment, the solvent is ethanol or isopropanol.

The antireflection coating is prepared by one of the following methods:

(1) dissolving hyperbranched resin into a solvent, adding a silicon source and a catalyst into the solvent in which the hyperbranched resin is dissolved, fully reacting for 0.5-20h to obtain sol containing composite nano-particles with a core-shell structure, and adding an auxiliary agent to obtain the anti-reflection coating; or

(2) Mixing a silicon source, a catalyst and a solvent for 0.5-24h to prepare a silica gel body, adding a hyperbranched resin into the silica gel body to fully react for 0.5-48h to obtain composite nanoparticle sol, and adding an auxiliary agent to obtain the antireflection coating.

In another preferred embodiment, the composite nanoparticles have a particle size of 30-100 nm.

In another preferred embodiment, the auxiliary agent comprises a leveling auxiliary agent, and preferably, the leveling auxiliary agent is one or a combination of acrylic auxiliary agents, silicone auxiliary agents and fluorine-containing auxiliary agents.

The invention also provides a preparation method of the antireflection coating, which comprises the following steps:

(1) mixing a silicon source, a catalyst, a solvent and hyperbranched resin to prepare composite nanoparticle sol with a core-shell structure;

(2) adding a leveling auxiliary agent to obtain the antireflection coating;

the preparation method of the composite nanoparticle sol comprises any one of the following steps:

(1) dissolving hyperbranched resin into a solvent, adding a silicon source and a catalyst into the solvent in which the hyperbranched resin is dissolved, and fully reacting for 0.5-24h to obtain the composite nanoparticle sol; or

(2) Mixing a silicon source, a catalyst and a solvent for 0.5-24h to prepare a silica gel body, and adding hyper-branched resin into the silica gel body to fully react for 0.5-48h to obtain the composite nano-particle sol.

In a preferred example, the silicon source is Tetraethoxysilane (TEOS) and/or Tetramethoxysilane (TMOS), the hyperbranched resin is an acrylate oligomer, the catalyst is one or a combination of two of organic acid or inorganic acid, the solvent is ethanol or isopropanol, and the assistant comprises a leveling assistant.

The invention also provides antireflection glass, which comprises glass and an antireflection coating attached to the surface of the glass, wherein the inside of the antireflection coating is formed by accumulating approximately spherical hollow silicon oxide nano particles and a pore structure, the surface of the antireflection coating is of a closed pore structure, and the closed pore structure is formed by the hollow silicon oxide nano particles and silicon oxide filling gaps among the hollow silicon oxide nano particles.

In a preferred embodiment, the pencil hardness of the coating is 6H-8H.

In another preferred example, the antireflection glass is produced by the following method:

(1) the anti-reflection coating is coated on the surface of the glass,

(2) and (3) placing the glass coated with the coating at the temperature of 400-700 ℃ for thermal curing to obtain the antireflection glass.

The invention has the beneficial effects that:

the coating comprises the composite nano particles which are formed by coating spherical hyperbranched resin particles with silicon oxide with a network structure and have a core-shell structure, after the coating is formed on a substrate and is thermally cured, the core formed by hyperbranched resin in the composite nano particles can be burnt, hollow silicon oxide shells, namely the hollow nano particles and the pore structures (namely the gaps) among the hollow nano particles are left, and the gaps among the hollow nano particles on the surface of the coating are filled with silicon oxide to form a closed pore structure, so that the effect of improving the coating transmissivity and simultaneously increasing the coating weather resistance is achieved. The coating disclosed by the invention not only has an excellent anti-reflection function, but also has the remarkable advantages of simple process, high weather resistance, high cost performance and the like.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other alternative embodiments can be obtained according to the drawings without creative efforts.

FIG. 1 is a scanning electron microscope image of the coating surface of example 2 of the present invention

FIG. 2 is a scanning electron microscope image of a cross section of a coating layer in example 2 of the present invention

FIG. 3 is a transmission electron micrograph of an antireflection coating obtained in example 2 of the present invention

FIG. 4 is a graph of the transmittance of the double-sided coating of example 2 of the present invention

FIG. 5 is a transmittance curve before and after a single-side coating high-low temperature cycle test of a 3% hyperbranched resin coating of example 2 of the present invention

FIG. 6 is a graph of transmittance before and after acid resistance test of a single-coated layer of 3% hyperbranched resin coating of example 2 of the present invention

FIG. 7 is a graph of the transmittance before and after salt spray testing of a single-coated layer of 3% hyperbranched resin coating of example 2 of the invention.

Detailed Description

After extensive and intensive research, the inventor found that when composite nanoparticles formed by coating spherical hyperbranched resin particles with silicon oxide having a network structure on a glass sheet as a coating layer and thermally curing the coating layer, hyperbranched resin particles in the composite nanoparticles are burnt out to form a pore structure, so that the film layer has a certain porosity, and the weather resistance of the antireflection coating can be improved, and completed the invention.

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, the drawings are schematic and thus the size of the apparatus and device of the present invention is not limited by the size or scale of the schematic.

It is to be noted that, in the claims and the specification of the present patent, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the use of the verb "comprise a" to define an element does not exclude the presence of another, same element in a process, method, article, or apparatus that comprises the element.

Example 1

The embodiment provides a weather-resistant closed-cell antireflection coating, which mainly comprises a silicon source, a hyperbranched resin, an auxiliary agent, a catalyst and a solvent, wherein the silicon source is alkoxy silane, the catalyst is acid, the solvent is alcohol, and the mixture ratio of the components in parts by weight is as follows: 3 to 5 percent of silicon source, 1 to 10 percent of hyperbranched resin and 85 to 96 percent of auxiliary agent, catalyst and solvent. The antireflection coating is prepared by one of the following methods:

The core in the core-shell structure is formed by hyperbranched resin which can be burnt out at high temperature, the resin serving as a template agent of the core structure exists in the weather-resistant closed-cell antireflection coating, and the shell structure is formed by coating spherical particles of the hyperbranched resin with the silica gel. Preferably, the particle diameter of the composite nano-particles is 30-100nm, and the composite nano-particles account for no more than 15% of the mass fraction of the coating.

The silicon source is Tetraethoxysilane (TEOS) and/or Tetramethoxysilane (TMOS), the hyperbranched resin is acrylate oligomer, the solvent is ethanol and/or isopropanol, and the catalyst is one or a mixture of inorganic acid (hydrochloric acid, nitric acid and the like) and/or organic acid (formic acid, acetic acid, citric acid and the like). The leveling auxiliary agent is one or a combination of more of acrylic acid, organic silicon and fluorine-containing auxiliary agents.

When the coating is used, the coating is coated on a substrate and then is subjected to thermosetting, the core and the leveling auxiliary agent formed by the hyperbranched resin in the composite nano particles can be burnt off during thermosetting, the hollow silicon oxide shell, namely the hollow nano particles, are left, and the gaps between the hollow nano particles on the surface of the coating are filled by silicon oxide to form a closed pore structure, so that the effect of improving the coating transmissivity and simultaneously increasing the coating weather resistance is achieved. Preferably, the temperature for thermal curing is 400-700 ℃, and the time for thermal curing is 10 min.

Example 2

The embodiment provides a specific preparation method of a weather-resistant closed-cell antireflection coating, and the preparation method comprises the following steps:

step 1: at normal temperature, adding diluted 0.1M catalyst hydrochloric acid into solvent ethanol for stirring, adding Tetraethoxysilane (TEOS) in the stirring process, and stirring for 24 hours to obtain a network silica gel body;

step 2: taking six parts of the silica gel prepared in the step 1, adding 1%, 2%, 3%, 4%, 5% and 10% of acrylate oligomer by weight of the same amount of the silica gel in the process of stirring the six parts of the same silica gel, and stirring for reaction for 12 hours to obtain the weather-resistant closed-cell antireflection coating;

and step 3: and (3) respectively adding a leveling auxiliary agent accounting for 0.1 percent of the weight of the silica gel into the six parts of the weather-resistant closed-cell antireflection coating prepared in the step (2) to obtain six parts of the weather-resistant closed-cell antireflection coating with excellent spreading performance.

Example 3

This example provides another specific method for preparing a weatherable, closed-cell anti-reflective coating, comprising the steps of:

step 1: at normal temperature, adding 2%, 2.5%, 3%, 3.5%, 4% and 6% of hyperbranched resin acrylate oligomer into an ethanol solvent, and fully dissolving;

step 2: adding Tetraethoxysilane (TEOS) and 0.1M hydrochloric acid catalyst into the fully dissolved hyperbranched resin ethanol solution obtained in the step (1), and reacting for 24 hours to obtain the weather-resistant closed-cell antireflection coating;

and step 3: and (3) adding a leveling auxiliary agent which is 0.1 percent of the weight of the silica gel into the weather-resistant closed-cell antireflection coating in the step (2), wherein the leveling auxiliary agent is one or more of acrylic acid type, organic silicon type and fluorine-containing auxiliary agents, so that the weather-resistant closed-cell antireflection coating with excellent spreading performance is obtained.

Example 4

This example provides a method of using, i.e., using, a weatherable closed-cell anti-reflective coating, by first applying 6 parts of the weatherable closed-cell anti-reflective coating obtained in example 2 to a previously cleaned K9 glass by dip coating, heat curing the coated glass substrate at a temperature of 500 ℃ for 10 minutes, and testing the weatherable closed-cell anti-reflective coating-coated glass after curing as follows:

scanning of the coating can be observed from fig. 1 and fig. 2, the coating is formed by stacking approximately spherical hollow nano particles and a pore structure, gaps among the hollow nano particles on the surface of the coating are filled with silicon oxide to form a closed pore structure, and the core-shell structure of the particles can be seen from a transmission electron microscope image of the antireflection coating in fig. 3. From the transmittance profile plot of the coating (fig. 4) it can be seen that the added amount of hyperbranched resin is highest at 3% transmittance. The coating is subjected to high and low temperature cycle test (figure 5), acid resistance test (figure 6) and salt spray test (figure 7), and the coating is free from shedding, stripping and wrinkling phenomena, the transmittance is changed within a standard acceptable range, and the pencil hardness of the coating is 6H-8H.

Example 5

This example is similar to example 4, except that the antireflective coating used was the coating from example 3, and the test results were the same as in example 4.

The test results of examples 4 and 5 show that the coating prepared by the invention is coated on the surface of a substrate to form a coating layer, and the coating layer improves the transmissivity and simultaneously increases the weather resistance.

The weather-resistant closed-cell antireflection coating and the performance of the formed coating are not affected by various leveling aids, and the leveling aids can be burnt out at high temperature and do not react with any substance in the weather-resistant closed-cell antireflection coating. No matter which leveling aid is selected, the optimal addition proportion can be selected, and the optimal spreading performance is realized.

The applicant states that the present invention is illustrated by the detailed method of the present invention through the above examples, but the present invention is not limited to the above detailed method, i.e. it does not mean that the present invention must be implemented by the above detailed method, for example, the application of the hyperbranched resin is not limited to the acrylate oligomer, and it is possible for a person skilled in the art to use the hyperbranched resin capable of spontaneously forming spherical particles of nanometer size in a hydrophilic solvent without affecting the optical properties and weather resistance of the film.

Therefore, it should be noted that: it will be apparent to those skilled in the art that various modifications and equivalents can be made without departing from the spirit of the invention, and it is intended that all such modifications and equivalents as fall within the true spirit and scope of the invention as defined by the appended claims be interpreted in accordance with the breadth to which the invention pertains.

Claims

1. An antireflection coating for antireflection glass consists of a silicon source, hyperbranched resin, an auxiliary agent, a catalyst and a solvent, and is characterized in that the silicon source is alkoxy silane, the catalyst is acid, and the solvent is alcohol; the proportioning relation of each component is as follows by weight:

3% -5% of silicon source;

1-10% of hyperbranched resin;

85% -96% of auxiliary agent, catalyst and solvent;

the solvent is a hydrophilic solvent, and the hyperbranched resin is hyperbranched resin capable of spontaneously forming nano-sized spherical particles in the hydrophilic solvent;

the antireflection coating is prepared by one of the following methods:

(1) dissolving hyperbranched resin into a solvent, adding a silicon source and a catalyst into the solvent in which the hyperbranched resin is dissolved, fully reacting for 0.5-20h to obtain sol containing composite nano-particles with a core-shell structure, and adding an auxiliary agent to obtain the anti-reflection coating; alternatively, the first and second electrodes may be,

(2) mixing a silicon source, a catalyst and a solvent for 0.5-24h to prepare a silica gel body, adding a hyperbranched resin into the silica gel body to fully react for 0.5-48h to obtain composite nanoparticle sol, and adding an auxiliary agent to obtain the antireflection coating;

the core in the core-shell structure is formed by hyperbranched resin which can be burnt out at high temperature, and the shell structure is formed by coating the spherical particles of the hyperbranched resin with the silica gel.

2. The anti-reflective coating of claim 1, wherein said silicon source is Tetraethoxysilane (TEOS) and/or Tetramethoxysilane (TMOS).

3. The anti-reflective coating of claim 1, wherein the hyperbranched resin is an acrylate oligomer.

4. The anti-reflective coating of claim 1, wherein the catalyst is one or a combination of organic or inorganic acids.

5. The anti-reflective coating of claim 1, wherein said solvent is ethanol or isopropanol.

6. The anti-reflective coating of claim 1, wherein the composite nanoparticles have a particle size of 30 to 100 nm.

7. The antireflection coating of claim 1 wherein the additive comprises a leveling aid selected from one or a combination of acrylic leveling aids, silicone leveling aids, and fluorine-containing leveling aids.

8. An antireflection glass comprising a glass and an antireflection coating attached to a surface of the glass, the antireflection coating being the antireflection coating described in any one of claims 1 to 7; the antireflection coating is characterized in that the inside of the antireflection coating is formed by piling approximately spherical hollow silicon oxide nano particles and a pore structure, the surface of the antireflection coating is of a closed pore structure, and the closed pore structure is composed of the hollow silicon oxide nano particles and silicon oxide filling gaps among the hollow silicon oxide nano particles.

9. The reduced reflection glass according to claim 8, wherein the coating has a pencil hardness of from 6H to 8H.

10. The reduced reflection glass according to claim 8, wherein the reduced reflection glass is produced by a method comprising:

(1) the anti-reflection coating is coated on the surface of the glass,

11. A method for preparing an antireflection coating according to claim 1, characterized by comprising the steps of:

(2) adding a leveling auxiliary agent to obtain the antireflection coating;

(1) dissolving hyperbranched resin into a solvent, adding a silicon source and a catalyst into the solvent in which the hyperbranched resin is dissolved, and fully reacting for 0.5-20h to obtain the composite nanoparticle sol; or

12. The method of claim 11, wherein the silicon source is Tetraethoxysilane (TEOS) and/or Tetramethoxysilane (TMOS), the hyperbranched resin is an acrylate oligomer, the catalyst is one or a combination of two of an organic acid or an inorganic acid, and the solvent is ethanol or isopropanol.