CN113321428B

CN113321428B - Antibacterial glass product and preparation method thereof

Info

Publication number: CN113321428B
Application number: CN202110578689.6A
Authority: CN
Inventors: 胡波
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-05-26
Filing date: 2021-05-26
Publication date: 2023-05-09
Anticipated expiration: 2041-05-26
Also published as: CN113321428A

Abstract

The invention discloses an antibacterial glass product and a preparation method thereof, and the preparation method of the antibacterial glass product provided by the invention comprises the following steps: providing a silver brine solution and a sodium ion-containing glass article in a reaction kettle, at least a portion of the surface of the glass article being covered by the silver brine solution; step two: setting the temperature and the pressure in the reaction kettle to enable the silver salt aqueous solution to be subcritical aqueous solution for reaction; step three: and cooling after the reaction is finished, taking out the glass product with the surface doped with silver ions, cleaning and drying. The preparation method of the antibacterial glass product provided by the invention is simple and easy to operate, and has short time consumption and greatly reduced cost. The silver ion antibacterial layer uniformly distributed on the surface of the glass product can be obtained without a high-temperature annealing step, and the obtained antibacterial glass product has a durable antibacterial effect.

Description

Antibacterial glass product and preparation method thereof

Technical Field

The invention belongs to the technical field of glass products, and particularly relates to an antibacterial glass product and a preparation method thereof.

Background

Glass products are often used for food placement, which requires certain antimicrobial properties. In the prior art, an antibacterial layer is formed on the surface of a glass product to realize the antibacterial performance of the glass product, and one of the methods for forming the antibacterial layer is to form a silver ion permeable layer on the surface of the glass product in an ion diffusion manner.

CN105523266B discloses that adding silver nitrate to potassium nitrate and performing exchange of glass surface ions and silver ions by high temperature melting requires very high temperature, resulting in high process costs. CN111499219a discloses that adding silver nitrate to an aqueous solution and spraying on the surface of a container, heating at high temperature to promote ion exchange, the process is complex, the dispersion has fluidity, a uniform surface functional layer is not easy to form, an effective antibacterial layer is difficult to form, and sufficient silver ions are generated on the surface of the container.

CN104192398A discloses that a silver ion layer is formed on the surface of glass by adding silver ions into an aqueous solution, then heating at 80-90 ℃ and then performing a thermal diffusion treatment. CN111925132a discloses an antibacterial glass and a preparation method thereof, the glass is soaked in an antibacterial liquid, and silver ions are promoted to diffuse into the glass at the temperature of 30-100 ℃. When an ion diffusion mode is adopted to form a silver ion permeation layer on the surface of glass, the conventionally used process is complex and has more steps, particularly when a thermal diffusion step is carried out, the required process temperature is very high, the time and the cost are long, and the obtained antibacterial glass product has a durable antibacterial effect.

Disclosure of Invention

In view of all or part of the above-mentioned deficiencies of the prior art, the object of the present invention is: the preparation method is simple and easy to operate, the time consumption is short, the cost is greatly reduced, the surface of the glass product can obtain a silver ion antibacterial layer uniformly distributed without a high-temperature annealing step, and the obtained antibacterial glass product has a lasting antibacterial effect.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a preparation method of an antibacterial glass product, which comprises the following steps:

step one: providing a silver brine solution and a sodium ion-containing glass article in a reaction kettle, at least a portion of the surface of the glass article being covered by the silver brine solution;

step two: setting the temperature and the pressure in the reaction kettle to enable the silver salt aqueous solution to be subcritical aqueous solution for reaction;

step three: and cooling after the reaction is finished, taking out the glass product with the surface doped with silver ions, cleaning and drying.

The method utilizes subcritical silver salt water solution to form a silver ion penetrating layer on the surface of the glass product containing sodium ions, and silver ions in the silver salt water solution are subjected to ion exchange with sodium ions in the glass product, so that the silver ions penetrate into the surface layer of the glass product. The preparation method adopted by the invention only relates to silver salt water solution preparation, heating up and boosting and cooling down in the reaction kettle, and does not need high-temperature annealing or other complicated steps. The preparation method provided by the invention is simple and easy to operate, and has short whole-course time consumption and reduced energy consumption; only the silver salt aqueous solution is provided as the raw material, and high-temperature annealing is not needed, so that the process is more environment-friendly and the cost is reduced.

In the prior art, when a silver ion penetrating layer is formed on the surface of glass by using molten silver salt, a preheated glass product is required to be placed into molten salt, and the glass product is taken out from the molten salt after the reaction is finished. The silver salt water solution is used as a reactant, and the silver salt water solution and the glass product containing sodium ions are placed in the reaction kettle, so that the glass product is not required to be preheated, the energy consumption is reduced, and the process is more environment-friendly.

Subcritical water, also known as super heated water, high pressure hot water or hot liquid water, means that the water is heated to a high temperature above 100 ℃ and below 374 ℃ below the critical temperature under a certain pressure (usually 22MPa below the critical pressure). The boiling point of water is 100 ℃, and under normal pressure, water vapor is continuously released in the boiling process, and the volume of the water is continuously reduced. When the temperature is higher than 100 ℃, the gas can not be released in a closed state, and the water vapor and the water reach equilibrium and are in a gas-liquid coexisting state. The hydrogen bond, ion hydration, ion association, cluster structure, etc. of the fluid microstructure change in the subcritical state. Therefore, subcritical water has a great difference in physicochemical properties from water at normal temperature and pressure, and is different from water in a normal state in density, dielectric constant, viscosity, diffusion coefficient, conductivity and solubility. Subcritical water has the characteristics of low cost, no toxicity, good mass transfer, heat transfer and the like, and is an environment-friendly medium.

Compared with water at normal temperature and normal pressure, the chemical reaction in subcritical water can increase the reaction rate and reduce the reaction temperature of partial high-temperature reaction. The silver salt aqueous solution is in a liquid state at a temperature of less than 100 ℃, the ion diffusion speed is slow, the required reaction time is long, and the ion exchange speed by utilizing the silver salt aqueous solution in a subcritical state is faster. The temperature of the subcritical silver salt water solution is higher than 100 ℃ and lower than the critical temperature 374 ℃, and the subcritical silver salt water solution is in a high-pressure water vapor coexistence environment, so that the ion diffusion speed is greatly improved, the required reaction time is greatly shortened, and the time consumption is short.

The silver ions can only be contacted with bacteria when in a free state to play an antibacterial role, so that trace silver ions are required to be slowly released from the surface of a glass product, and the common components of microorganisms are continuously damaged or dysfunctional is continuously caused, so that a lasting antibacterial effect is generated. The silver carrying amount on the surface of the glass product can influence the silver ion release period of the antibacterial glass product in the use process, the antibacterial durability can be reduced when the silver carrying amount is too low, and when the silver carrying amount is higher, the antibacterial performance of the glass product is durable, but the utilization rate of silver ions can be reduced when the silver carrying amount is too high. Silver-carrying capacity on the surface of the glass product also affects the slow-release speed of silver ions, and too high silver-carrying capacity can cause too fast silver ion loss, which can reduce the service life of the antibacterial glass product, and can cause excessive silver ions to be ingested by a human body when eating food in long-term contact with the surface of the antibacterial glass product.

The silver loading on the surface of the glass product depends on the surface silver ion content and the surface silver ion depth, and the higher the silver ion content and the penetration depth, the higher the silver loading. Under the temperature and pressure of subcritical state, the silver ion content and the penetration depth of the surface of the glass product are relatively high in a high-pressure water vapor environment; and the antibacterial glass product with higher silver loading is difficult to obtain in a shorter reaction time at normal temperature and normal pressure, and the durability of the antibacterial effect is seriously affected by the low silver loading.

The silver gelation of the silver-impregnated ion layer can be caused by the excessively high reaction temperature, so that the antibacterial performance of the silver-impregnated ion layer is reduced, and the light transmittance of the glass product is reduced. Moreover, the high temperatures can also lead to decomposition of, for example, nitrate salts, leaving yellow or brown spots on the glass surface, severely affecting the quality of the appearance of the glass article. In the prior art, high-temperature diffusion annealing is also generally needed when the antibacterial glass product is prepared, the annealing temperature is high and can reach 400 ℃ or even 500 ℃, high cost is generated, and the process is relatively complex. The preparation method provided by the invention can obtain the antibacterial glass product meeting the requirements without high-temperature diffusion annealing, and has the advantages of simple process, short time consumption and low cost.

The glass article is a glass vessel having an inner surface and an outer surface, the inner surface and/or the outer surface of the glass vessel being covered with the aqueous silver salt solution.

In the first step, the silver salt water solution is placed in the reaction kettle, and the glass ware is placed in the silver salt water solution, so that the inner surface and the outer surface of the glass ware are immersed by the silver salt water solution. In this manner, both the inner and outer surfaces of the glassware may form a silver ion-impregnated layer.

In the first step, the silver salt water solution is placed in the glass vessel, the silver salt water solution is only in contact with the inner surface of the glass vessel, and the glass vessel is placed in the reaction kettle. In this way, a silver ion-impregnated layer may be formed only on the inner surface of the glassware.

In the second step, the temperature in the reaction kettle is set to be 110-300 ℃. The reaction temperature has great influence on the diffusion speed of silver ions, and when the temperature is too low, the ion diffusion speed is too slow, and the silver ion content and the penetration depth on the surface of the glass product do not reach the standard; when the temperature is too high, the ion diffusion speed is increased, but silver ions are easily reduced into silver at the moment, so that the light transmittance of the glass is reduced, for example, the penetration depth is too deep, and the silver ions in the excessive depth cannot be diffused to the surface of the glass for slow release. The reaction temperature is set within the range of 110-300 ℃, so that the ion diffusion speed and the glass transmittance of the better combination can be achieved. Meanwhile, the reaction equipment required for the excessively high temperature is relatively complicated. The reaction temperature is further preferably 110-200 ℃, and the antibacterial glass product meeting the requirements can be obtained, so that the cost is saved and the reaction condition is milder.

In order to bring the silver salt aqueous solution into a subcritical state, it is necessary to keep the temperature and pressure of the system within suitable ranges. When the temperature is set at 110-300 ℃, the pressure in the system can be correspondingly adjusted along with the temperature, and silver salt water solution in a proper subcritical state can be formed.

In the first step, the concentration of the silver salt aqueous solution is 0.005wt% to 20wt%. The concentration of the silver salt aqueous solution directly influences the concentration of silver ions in the reaction process, thereby influencing the speed of the ion diffusion reaction, the silver ion content of the finally formed silver-ion-permeable layer and the silver carrying amount.

In the second step, after the temperature in the reaction kettle is set, the temperature is maintained until the reaction is finished, and the reaction time is 10-360 minutes. When the reaction is carried out, the heat preservation is carried out in the reaction kettle until the reaction is finished, the heat preservation time, namely the reaction time, can be further shortened to 10-120 minutes, and the silver ion content and the penetration depth of the surface meeting the requirements can be obtained within the reaction time of 10-120 minutes. Parameters such as reaction temperature, reaction time and the like, and the state and the addition amount of the silver salt aqueous solution can greatly influence the performance of the antibacterial glass product, and the factors are controlled in a proper range and matched with each other, so that the antibacterial requirement of the product can be met.

The silver salt is at least one selected from silver nitrate, silver sulfate, silver chlorate, silver perchlorate, silver acetate, silver lactate, silver citrate and silver halide.

The glass product is made of borosilicate glass or soda lime glass. Wherein, borosilicate glass has good thermal shock resistance, and the prepared glass product has excellent thermal shock resistance.

The invention also provides an antibacterial glass product, which is prepared by adopting the preparation method of the antibacterial glass product in the scheme.

The surface silver ion content of the antibacterial glass product is 0.001-2 wt%. Preferably, the surface silver ion content is 0.01wt% to 2wt%, and may further preferably be 0.1wt% to 2wt%. The surface silver ion content will affect the durability of the antimicrobial properties, within a certain range, the higher the content the better the durability, while too high will affect the permeability of the glass.

The surface silver ion depth of the antimicrobial glass article is greater than or equal to 1 micron. Preferably, the surface silver ion depth is greater than or equal to 5 microns, and in order to maintain the durability of silver ion release, the surface silver ion depth is preferably in excess of 5 microns. And may further preferably be greater than or equal to 10 microns.

The content of silver ions is too low or the penetration depth is too shallow, so that the antibacterial effect is reduced; the too high silver ion content or too deep penetration depth can increase the consumption of silver ions and the cost, and can reduce the light transmittance of the glass substrate, and the too high silver ion content can also cause uneven silver ion dispersion. Meanwhile, the diffusion coefficient of silver ions on the surface layer of the glass is limited, and silver ions exceeding a certain depth cannot diffuse to the surface of the glass, so that the effect of inhibiting microorganisms cannot be achieved.

Compared with the prior art, the invention has at least the following beneficial effects:

1. according to the invention, antibacterial treatment is carried out on the surface of the glass product containing sodium ions, a silver ion penetrating layer is formed on the surface of the glass product by utilizing subcritical silver salt water solution, and silver ions in the formed silver ion penetrating layer are uniformly distributed. The invention can select to only perform antibacterial treatment on part of the surfaces of the glass products, and can also perform antibacterial treatment on all the surfaces simultaneously. The preparation method of the antibacterial glass product provided by the invention is simple and easy to operate, does not need a high-temperature annealing step, is short in time consumption, uses few raw materials, and greatly reduces the cost.

2. According to the invention, the glass substrate is stably combined with silver ions, the silver ions can be released on the surface of the glass permanently and slowly, and the prepared glass product has obvious fresh-keeping and antibacterial effects. The antibacterial glass product provided by the invention has the effect of inhibiting microorganisms, and can achieve the antibacterial effect of more than 99.9% on common escherichia coli and staphylococcus aureus.

Drawings

In order to more clearly illustrate the technical solutions of the specific embodiments of the present invention, the drawings that are required to be used in the description of the embodiments will be briefly described below.

FIG. 1 is a schematic flow chart of a method for preparing an antimicrobial glass article according to the present invention;

FIG. 2 is a graph showing the relationship between the silver loading and the surface silver ion content and the surface silver ion depth.

Detailed Description

The technical solutions in the specific embodiments of the present invention will be clearly and completely described below. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. It should be noted that, in order to describe the technical solution more specifically, the steps described in the present embodiment do not strictly correspond to the steps described in the summary of the invention.

Referring to fig. 1, a schematic flow chart of a preparation method of an antibacterial glass product provided by the invention is shown. The glass articles used in the following embodiments are glassware (e.g., glass crispers, glass bottles, glasses, etc.), and in other embodiments glass articles such as flat glass sheets may also be used. The glasses used in the following embodiments are exemplified by borosilicate glasses only, and the present invention is not limited thereto, and glasses made of conventional glasses containing sodium ions such as soda lime glass may be used.

The specific embodiment provides a preparation method of an antibacterial glass product, which comprises the following steps:

s1: preparing 500ppm (0.05 wt%) silver nitrate aqueous solution, placing it in a reaction kettle; and cleaning the borosilicate glass vessel, soaking the borosilicate glass vessel in the silver nitrate aqueous solution, and immersing the inner surface and the outer surface of the borosilicate glass vessel in the silver nitrate aqueous solution.

S2: setting the temperature in the reaction kettle to be 110-200 ℃, and correspondingly, obtaining specific system pressure through setting the temperature; the silver nitrate aqueous solution was changed to a subcritical aqueous solution, and the reaction was carried out for 60 minutes while maintaining the temperature.

S3: and cooling after the reaction is finished, taking out the borosilicate glass ware with the surface doped with silver ions, cleaning by ultrasonic waves, and drying in an oven for 10-60 minutes.

In this embodiment, an aqueous silver nitrate solution is used, and in other embodiments, an aqueous silver nitrate solution of, for example, silver sulfate, silver chlorate, silver perchlorate, silver acetate, silver lactate, silver citrate, silver halide, or the like may be used. The concentration of the silver nitrate aqueous solution used is 500ppm, and in other embodiments, other concentrations of the silver nitrate aqueous solution may be used, and the reaction time and the reaction temperature may be adjusted according to the concentration of the silver nitrate aqueous solution. Parameters such as reaction time can also be adjusted according to specific conditions and the amount of silver loading required.

In the above embodiments, the borosilicate glass vessel has silver ion-impregnated antimicrobial layers formed on both the inner and outer surfaces. In other embodiments, the silver nitrate aqueous solution can be directly poured into the borosilicate glass vessel, and then the borosilicate glass vessel is put into a reaction kettle, and only the inner surface of the obtained antibacterial glass vessel is provided with a silver ion-permeable antibacterial layer. Alternatively, the surface of the glass article that does not require silver impregnation may be masked with, for example, a waterproof high temperature resistant tape, and then the glass article is immersed in an aqueous solution of silver nitrate, the surface not forming a silver ion impregnated layer. The drying mode can be various, such as hot air drying, infrared baking and the like.

Example 1 a 500ppm aqueous solution of silver nitrate was prepared and placed in the reaction kettle; and cleaning the borosilicate glass ware, soaking the borosilicate glass ware in a silver nitrate aqueous solution, and immersing the inner surface and the outer surface of the borosilicate glass ware in the silver nitrate aqueous solution. The temperature in the reaction vessel was set at 110℃to turn the silver nitrate aqueous solution into a subcritical aqueous solution, and the reaction was carried out at that temperature for 60 minutes. And cooling after the reaction is finished, taking out the borosilicate glass ware with the surface doped with silver ions, cleaning by ultrasonic waves, and drying in a vacuum oven for 30 minutes.

Example 2 differs from example 1 in that the temperature in the reaction vessel was set at 125 ℃.

Example 3 differs from example 1 in that the temperature in the reaction vessel was set at 165 ℃.

Comparative example 1 is different from example 1 in that the temperature of the silver nitrate solution was set to 40 deg.c at normal pressure.

Comparative example 2 is different from example 1 in that the temperature of the silver nitrate solution was set to 90 deg.c at normal pressure.

The glasses prepared in the above examples and comparative examples were subjected to atomic mass spectrometry analysis to obtain the following test results.

Table 1 test results of examples and comparative examples

	Temperature (. Degree. C.)	Surface silver ion depth (microns)	Surface silver ion content (wt%)	Silver loading amount
					Comparative example 1	40	0.5	0.15	0.075
Comparative example 2	90	0.8	0.18	0.144
					Example 1	110	2.5	0.35	0.875
Example 2	125	4	0.4	1.6
					Example 3	165	9	0.5	4.5

Silver loading = depth of surface silver ion (depth of silver penetration) x surface silver ion content

The reaction temperature of the comparative example 1 and the comparative example 2 is below 100 ℃, and after the reaction is carried out for 60 minutes, the depth of silver ions on the surfaces of the comparative examples is less than 1 micrometer. The reaction temperatures of examples 1-3 were all above 100 ℃, and the surface silver ion depths were all greater than 1 micron within the same reaction time of 60 minutes as in the comparative example, and after exceeding 110 ℃, the temperatures continued to rise, with a significant rise in silver ion depths. At 110 ℃ reaction temperature, the silver ion depth can reach 2.5 microns; at 125 ℃ reaction temperature, the silver ion depth can reach 4 microns; at a reaction temperature of 165 ℃, the silver ion depth can reach 9 microns.

Experiments show that the penetration depth of silver ions is limited in the same reaction time under normal pressure and at the temperature lower than 100 ℃. When the system temperature is set above 100 ℃, the penetration depth of silver ions is deeper within the same reaction time, and the requirements of better penetration depth can be met.

Experiments also show that the silver ion content of the surface is relatively low in the same reaction time under normal pressure and at the temperature lower than 100 ℃. And when the system temperature is set above 100 ℃, the silver ion content is also greatly increased.

The silver loading on the glass surface depends on the surface silver ion content and the surface silver ion depth (silver penetration depth), and referring to fig. 2, the integrated area shown in fig. 2 indicates the silver loading. The higher silver carrying amount can lead the antibacterial glassware to have longer ion release period and lasting antibacterial performance in the use process. When the temperature of the system is above 110 ℃, the silver nitrate aqueous solution is in a subcritical state, the surface of the sample is in a high-pressure water vapor environment, and a deeper silver penetration depth and a higher silver ion content are obtained in a shorter reaction time, so that the requirements of the silver ion depth and the silver ion content are met. The penetration depth of silver ions influences the release of silver ions, and the limited penetration depth can be used for releasing silver ions.

Zhou Yanyan, zhang Shuhua, li Yue, etc. the development of silver-loaded porous antimicrobial glass [ J ]. Optical technology, 2010,36 (003): 424-427. It is mentioned that the silver loading increases with increasing temperature of the water bath, but when the temperature is above 40 ℃, the silver loading changes little, hardly affected, and when the temperature reaches 80 ℃, the silver loading even decreases. The invention makes the silver nitrate water solution present subcritical state by strictly controlling the temperature range and the pressure range of the reaction system, and under the subcritical state, the higher silver carrying amount can be obtained on the surface of the glassware after the temperature is raised.

By setting proper temperature and pressure, the silver nitrate aqueous solution is in a subcritical state, so that the depth of silver ions, the content of silver ions and the silver loading amount on the surface are greatly increased in a short reaction time, and the silver ions on the surface of the obtained antibacterial glassware are uniformly distributed. The conventional method needs high-temperature molten salt ion exchange, the ion exchange process can be effectively completed without high-temperature annealing or other complicated steps, the required reaction time is short, and the cost is low. The prepared antibacterial glassware has high silver-carrying capacity and durable antibacterial performance, and can achieve the inhibition effect of more than 99.9% on escherichia coli and staphylococcus aureus through detection.

The principle of the invention is illustrated by the above examples: the invention converts the silver nitrate aqueous solution under normal pressure into the subcritical silver nitrate aqueous solution by setting the temperature and the pressure of the system. And utilizing silver ions in the subcritical silver nitrate aqueous solution to exchange ions with sodium ions on the surface layer of the glassware to form a silver ion penetrating layer on the surface layer of the glass. The invention uses the surface ion diffusion method to carry out ion exchange on the ions on the surface of the glass and the silver ions to form the silver ion permeation layer, the silver ion permeation layer is firmly combined with the glass ware, and the durable antibacterial effect can be exerted by slowly releasing the silver ions.

The above description of the embodiments is only intended to assist in understanding the method and core idea of the invention. It should be noted that it will be apparent to those skilled in the art that various improvements and modifications can be made to the present invention without departing from the principles of the invention, and such improvements and modifications fall within the scope of the appended claims.

Claims

1. A method of making an antimicrobial glass article comprising the steps of:

step two: setting the temperature and the pressure in the reaction kettle, wherein the temperature is 165-300 ℃ to enable the silver salt aqueous solution to be subcritical aqueous solution for reaction;

step three: cooling after the reaction is finished, taking out the glass product with the surface doped with silver ions, cleaning and drying; the silver ion content of the surface of the antibacterial glass product obtained by the reaction is 0.001-2wt% and the silver ion depth is more than or equal to 10 micrometers.

2. The method of making an antimicrobial glass article according to claim 1, wherein the glass article is a glass vessel having an inner surface and an outer surface, the inner surface and/or the outer surface of the glass vessel being covered with the aqueous silver salt solution.

3. The method of manufacturing an antimicrobial glass article according to claim 2, wherein in step one, the aqueous silver salt solution is placed in the reaction kettle, the glass is placed in the aqueous silver salt solution, and both the inner surface and the outer surface of the glass are immersed in the aqueous silver salt solution.

4. The method of manufacturing an antimicrobial glass article according to claim 2, wherein in step one, the aqueous silver salt solution is placed in the glass vessel such that the aqueous silver salt solution contacts only the inner surface of the glass vessel, and the glass vessel is placed in the reaction vessel.

5. The method of making an antimicrobial glass article according to any one of claims 1-4, wherein in step one, the concentration of the aqueous silver salt solution is from 0.005wt% to 20wt%; in the second step, after the temperature in the reaction kettle is set, the temperature is maintained until the reaction is finished, and the reaction time is 10-360 minutes.

6. The method of making an antimicrobial glass article according to any one of claims 1-4, wherein the silver salt is selected from at least one of silver nitrate, silver sulfate, silver chlorate, silver perchlorate, silver acetate, silver lactate, silver citrate, and silver halide.

7. The method of making an antimicrobial glass article according to any one of claims 1-4, wherein the glass article is a borosilicate glass or a soda lime glass.

8. An antimicrobial glass article prepared according to the method of any one of claims 1-7.