CN111333317A - High-potassium ultra-white glass and preparation method thereof - Google Patents

Abstract

The high-potassium ultra-white glass comprises the following components in percentage by mass: 71.0 to 73.0 percent of SiO₂12.5 to 13.5 percent of Na₂O, 11.5 to 12.5 percent of CaO, and 0.9 to 2.1 percent of K₂O, 1.4-1.6% of Al₂O₃0.15 to 0.25 percent of MgO. The preparation method of the high-potassium ultra-white glass comprises the following steps: taking 71.0-73.0 g of SiO₂21.7 to 22.7g of Na₂CO₃20.9-21.9 g of CaCO₃1.5 to 3.3g of K₂CO₃2.5 to 2.7g of Al (NO)₃)₃0.05-0.15 g of Mg powder at high temperatureMelting in a glass melting lifting furnace, and then placing the crucible filled with the materials in an annealing furnace for annealing. The ultra-white glass prepared by the method has high light transmittance and simple steps.

Description

High-potassium ultra-white glass and preparation method thereof

Technical Field

The invention relates to high-potassium ultra-white glass and a preparation method thereof.

Background

With the development of glass technology, emerging glass products such as hollow glass, tempered glass, energy-saving glass and the like are gradually replacing traditional glass products and are widely accepted and used by people. At present, ultra-white glass, which is packaging glass for manufacturing solar photovoltaic cells, is increasingly used and required; with the rapid development of the photovoltaic industry in China, the market of photovoltaic super-white glass is also greatly developed; analysis indicates that in the coming years, the demand of the photovoltaic super white glass is increased, and simultaneously, new requirements are put on the quality of the photovoltaic super white glass.

At present, proper amount of TiO is added₂Or MgO to increase the transmittance of the glass, but TiO₂The improvement of the light transmittance of the glass is very limited because of excessive Ti⁴⁺Can change the silicon-oxygen tetrahedron SiO in the glass₄Of the lattice structure of (2), and Ti in heat preservation⁴⁺Will react with the reducing substances in the glass to be reduced into Ti³⁺And block the silica bridge bond, thereby limiting the glassThe glass light transmittance is improved. The role of MgO as an alkaline earth oxide in glass on the one hand enables the depolymerization of the large tetrahedra resulting in a reduction in viscosity; on the other hand, because the electrovalence is higher than that of alkali metal and the ionic radius is not large, the bonding force is larger than that of alkali metal ions, oxygen ions are captured around the glass to increase the viscosity, so that when the MgO is excessive, the viscosity of the glass is increased (particularly, the viscosity is more obvious at low temperature), and the glass is easy to form larger-particle microcrystal, thereby being not beneficial to improving the light transmittance.

Disclosure of Invention

The invention aims to solve the first technical problem of providing high-potassium ultra-white glass with high light transmittance.

The second technical problem to be solved by the invention is to provide the preparation method of the high-potassium ultra-white glass, which has the advantages of simple steps, easily obtained raw materials and low cost.

In order to solve the first technical problem, the invention provides high-potassium ultra-white glass which comprises the following components:

71.0 to 73.0 mass percent of SiO₂12.5 to 13.5 percent of Na₂O, 11.5 to 12.5 percent of CaO, and 0.9 to 2.1 percent of K₂O, 1.4-1.6% of Al₂O₃0.15 to 0.25 percent of MgO.

In order to solve the second technical problem, the invention provides a preparation method of high-potassium ultra-white glass, which comprises the following steps:

(1) preparing materials: taking 71.0-73.0 g of SiO₂21.7 to 22.7g of Na₂CO₃20.9-21.9 g of CaCO₃1.5 to 3.3g of K₂CO₃2.5 to 2.7g of Al (NO)₃)₃0.05-0.15 g of Mg powder;

(2) melting: preheating a high-temperature glass melting lifting furnace to 1100 +/-50 ℃ at a heating rate of 5 +/-1 ℃/min for 220 +/-10 min, then shaking the lifting furnace, putting the ingredients into a crucible, putting the crucible into a furnace chamber, then lifting the ingredients, keeping the temperature at 1100 +/-50 ℃ for 60 +/-5 min, then heating the ingredients from 1100 +/-50 ℃ to 1300 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min for two hours at a constant temperature, finally heating the ingredients to 1500 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min, and taking out the crucible containing the ingredients after 2 hours of heat preservation;

(3) annealing: and (3) annealing the crucible filled with the material in an annealing furnace at the annealing temperature of 550 +/-20 ℃ for 3 +/-0.5 hours, and then preserving the heat at the temperature of 280-300 ℃ for 2 hours to finish the annealing.

K₂Role of O in glass: on the one hand, the fluxing agent is a good fluxing agent and can react with SiO at a lower temperature₂Silicate is generated through reaction, so that the melting speed of the glass is increased, and the uniformity of glass melting components is improved; on the other hand K₂O is better than MgO, can reduce the viscosity of the glass liquid, and can prevent the glass from being agglomerated into larger grain microcrystal, thereby enhancing the luster and the transparency of the glass.

In order to facilitate the study of K₂The influence of O on the light transmittance of the glass is realized, and Na is selected according to the particularity of the characteristics of the application range of the ultra-white glass₂O-CaO-SiO₂Three-phase systems were studied. In Na₂O-CaO-SiO₂In a three-phase glass system, the thermal expansion coefficient of the glass is reduced, and the thermal stability, softening temperature, hardness and viscosity of the glass are improved by proper amount of SiO₂If SiO, for control₂When the content is too high, the melting temperature is increased and the glass crystallization probability is increased, and SiO can be obtained by analyzing the three-phase diagram₂The content is 62.0-75.0%. CaO acts as a stabilizer in the glass, but when the content is too high, the glass crystallization probability increases, and the glass becomes brittle, and the CaO content is generally about 12%. Na (Na)₂O is a network exo-oxide, Na₂O can provide free oxygen to increase the ratio of O/Si in the glass structure, so that bond breaking occurs, the viscosity of the glass can be reduced, the glass is easy to melt, but the O can simultaneously increase the expansion coefficient of the glass, and reduce the thermal stability and the chemical stability of the glass, so that the introduction amount is controlled to be about 13.0 percent, and is supplemented with about 1.5 percent of Al₂O₃And about 0.2% MgO.

The invention has the advantages that: the super-white glass provided by the invention has high light transmittance. And the preparation method has simple steps, easily obtained raw materials and low cost.

Drawings

FIG. 1 is a temperature rising program curve in examples one to three.

FIG. 2 is an annealing curve in examples one to three.

FIG. 3 is a graph of the transmittance of a sample of the example in the wavelength range of 340-800 nm.

FIG. 4 is a graph of the transmittance of the sample of example two in the wavelength range of 340-800 nm.

FIG. 5 is a graph of the transmittance of the three samples of example in the wavelength range of 340-800 nm.

Detailed Description

The first embodiment is as follows:

a preparation method of high-potassium ultra-white glass comprises the following steps:

(1) preparing materials: taking 71.0-73.0 g of SiO₂21.7 to 22.7g of Na₂CO₃20.9-21.9 g of CaCO₃1.5 to 1.7g of K₂CO₃2.5 to 2.7g of Al (NO)₃)₃0.05-0.15 g of Mg powder;

(2) melting: preheating a high-temperature glass melting lifting furnace to 1100 +/-50 ℃ at a heating rate of 5 +/-1 ℃/min for 220 +/-10 min, then shaking the lifting furnace, putting the ingredients into a crucible, putting the crucible into a furnace chamber, then lifting the ingredients, keeping the temperature at 1100 +/-50 ℃ for 60 +/-5 min, then heating the ingredients from 1100 +/-50 ℃ to 1300 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min for two hours at a constant temperature, finally heating the ingredients to 1500 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min, and taking out the crucible containing the ingredients after 2 hours of heat preservation;

(3) annealing: and (3) annealing the crucible filled with the material in an annealing furnace at the annealing temperature of 550 +/-20 ℃ for 3 +/-0.5 hours, and then preserving the heat at the temperature of 280-300 ℃ for 2 hours to finish the annealing.

Example two:

a preparation method of high-potassium ultra-white glass comprises the following steps:

(1) preparing materials: taking 71.0-73.0 g of SiO₂21.7 to 22.7g of Na₂CO₃20.9-21.9 g of CaCO₃2.4 to 2.6g of K₂CO₃2.5 to 2.7g of Al (NO)₃)₃0.05-0.15 g of Mg powder;

(2) melting: preheating a high-temperature glass melting lifting furnace to 1100 +/-50 ℃ at a heating rate of 5 +/-1 ℃/min for 220 +/-10 min, then shaking the lifting furnace, putting the ingredients into a crucible, putting the crucible into a furnace chamber, then lifting the ingredients, keeping the temperature at 1100 +/-50 ℃ for 60 +/-5 min, then heating the ingredients from 1100 +/-50 ℃ to 1300 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min for two hours at a constant temperature, finally heating the ingredients to 1500 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min, and taking out the crucible containing the ingredients after 2 hours of heat preservation;

(3) annealing: and (3) annealing the crucible filled with the material in an annealing furnace at the annealing temperature of 550 +/-20 ℃ for 3 +/-0.5 hours, and then preserving the heat at the temperature of 280-300 ℃ for 2 hours to finish the annealing.

Example three:

a preparation method of high-potassium ultra-white glass comprises the following steps:

(1) preparing materials: taking 71.0-73.0 g of SiO₂21.7 to 22.7g of Na₂CO₃20.9-21.9 g of CaCO₃And 3.1 to 3.3g of K₂CO₃2.5 to 2.7g of Al (NO)₃)₃0.05-0.15 g of Mg powder;

(2) melting: preheating a high-temperature glass melting lifting furnace to 1100 +/-50 ℃ at a heating rate of 5 +/-1 ℃/min for 220 +/-10 min, then shaking the lifting furnace, putting the ingredients into a crucible, putting the crucible into a furnace chamber, then lifting the ingredients, keeping the temperature at 1100 +/-50 ℃ for 60 +/-5 min, then heating the ingredients from 1100 +/-50 ℃ to 1300 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min for two hours at a constant temperature, finally heating the ingredients to 1500 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min, and taking out the crucible containing the ingredients after 2 hours of heat preservation;

(3) annealing: and (3) annealing the crucible filled with the material in an annealing furnace at the annealing temperature of 550 +/-20 ℃ for 3 +/-0.5 hours, and then preserving the heat at the temperature of 280-300 ℃ for 2 hours to finish the annealing.

In the three embodiments, the temperature-raising program curve is shown in fig. 1, and the annealing curve is shown in fig. 2.

Glass sample density and transmittance testing:

density test procedure of glass:

density is the ratio of mass to volume, i.e., ρ m/V. 3 small glass samples are selected from 3 examples respectively, the mass m is weighed by a balance of one thousandth, the small glass samples are placed in 50mL measuring cylinders respectively after being recorded, water is added to the measuring cylinders to be injected to 20mL, the volume V of the glass samples is measured, the density of the glass is calculated respectively, and finally the average value is calculated.

And (3) a light transmittance testing process:

the transmittance T is the light intensity It of the transmitted light and the light intensity I of the incident light₀I.e. T ═ It/I₀，

The ultraviolet-visible spectrophotometer used in the detection detects the light transmittance of the glass. Now, cutting glass into rectangular glass sheets (18-20 mm in length and 6-8 mm in width) 3-4 mm in thickness, placing the cut glass samples into an ultraviolet-visible spectrophotometer, selecting the wavelength range of 340-:

the transmittance of the glass of the third embodiment at a wavelength of 600nm reaches 92.0%, mainly because the change of potassium ions directly affects the transmittance of the glass, and the potassium ions are beneficial to increasing the transmittance.

Experimental data for three formulation samples

Physical Properties	Example one	Example two	EXAMPLE III
				Set annealing temperature (. degree. C.)	550±10	550±10	550±10
Density (g/cm3)	2.48±0.01	2.49±0.01	2.50±0.01
				Maximum light transmittance at 550nm (%)	91.5±0.2	91.8±0.2	92.0±0.2

It follows that with K₂O increases and the density of the glass changes little (slightly increases), but K₂When the mass percentage content of O is increased from 0.2% to 0.6%, the maximum light transmittance of the glass is improved from 91.5% to 92%, and an experimental structure shows that the change of potassium ions directly influences the light transmittance of the glass, and the introduction of the potassium ions is beneficial to enhancing the light transmittance of the glass because K is used for increasing the light transmittance of the glass₂O is a good fluxing agent on the one hand and can react with SiO at a lower temperature₂Silicate is generated through reaction, so that the integral melting speed of the glass is increased, and the uniformity of glass melting components is improved; on the other hand K₂O is superior to MgO, can lower the viscosity of molten glass (because divalent magnesium ions have higher charge and smaller volume than monovalent potassium ions, and are easier to combine with free oxygen in the glass melting process, thereby improving the viscosity of the glass), can prevent the glass from being agglomerated into larger particle microcrystals, and the two actions enable K to be more effective₂O is more advantageous in that it enhances the transparency (i.e., light transmittance) of the glass.

Claims (2)

1. The high-potassium ultra-white glass is characterized by comprising the following components:

71.0 to 73.0 mass percent of SiO₂12.5 to 13.5 percent of Na₂O, 11.5 to 12.5 percent of CaO, and 0.9 to 2.1 percent of K₂O, 1.4-1.6% of Al₂O₃0.15 to 0.25 percent of MgO.

2. The method for preparing the high-potassium ultra-white glass according to claim 1, characterized by comprising the following steps:

(1) preparing materials: taking 71.0-73.0 g of SiO₂21.7 to 22.7g of Na₂CO₃20.9-21.9 g of CaCO₃1.5 to 3.3g of K₂CO₃2.5 to 2.7g of Al (NO)₃)₃0.05-0.15 g of Mg powder;

(2) melting: preheating a high-temperature glass melting lifting furnace to 1100 +/-50 ℃ at a heating rate of 5 +/-1 ℃/min for 220 +/-10 min, then shaking the lifting furnace, putting the ingredients into a crucible, putting the crucible into a furnace chamber, then lifting the ingredients, keeping the temperature at 1100 +/-50 ℃ for 60 +/-5 min, then heating the ingredients from 1100 +/-50 ℃ to 1300 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min for two hours at a constant temperature, finally heating the ingredients to 1500 +/-50 ℃ at a heating rate of 3 +/-0.5 ℃/min, and taking out the crucible containing the ingredients after 2 hours of heat preservation;

(3) annealing: and (3) annealing the crucible filled with the material in an annealing furnace at the annealing temperature of 550 +/-20 ℃ for 3 +/-0.5 hours, and then preserving the heat at the temperature of 280-300 ℃ for 2 hours to finish the annealing.

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