CN101244889A - A kind of fluorine-free environment-friendly opaque glass material and its manufacturing method - Google Patents

Abstract

A fluorine-free environment-friendly opaque glass material and a manufacturing method thereof belong to the field of new glass materials. The composition of the glass material is SiO ₂ -Al ₂ O ₃ -B ₂ O ₃ -P ₂ O ₅ -MgO-CaO-SrO-BaO-Li ₂ O-Na ₂ O-K ₂ O. The preparation method includes mixing the raw materials to make a uniform batch material, putting the batch material into a corundum crucible, melting at 1500-1520°C for 3 hours, pouring and molding, and annealing at 550-560°C for 1 hour. The production method of the present invention uses a small amount of phosphate instead of fluoride to produce an opacifying effect, which will not cause environmental pollution in the industrial production of opacified glass, and can avoid the short life of the glass kiln and safety problems caused by fluorine. Using dense network structure reconstruction technology, adjust the relative content of SiO ₂ and P ₂ O ₅ , and introduce alkali metal or alkaline earth metal oxide at the same time, the glass spontaneously separates phases during cooling to produce a significant opacification effect, and introduces a small amount of B ₂ O ₃ It enhances the opacifying effect of the glass, and at the same time introduces a certain amount of Al ₂ O ₃ , endowing the glass with excellent chemical stability.

Description

A kind of fluorine-free environment-friendly opaque glass material and its manufacturing method

technical field

The invention relates to a fluorine-free environment-friendly opaque glass material and a manufacturing method thereof, belonging to the field of new glass materials.

Background technique

Compared with ordinary transparent glass, opal glass has the characteristics of soft color, high purity and elegance. In recent years, the application of opacity glass has become more and more extensive. In addition to being used in daily utensils, architectural lighting and cosmetic packaging, it is also used in various wine bottles, architectural decoration materials and dental materials. The production scale is also gradually expanding. , showing a good market development prospect.

W，Frank M and Rheinberger V.Thermochimica Acta，1996，280-281：491-499.)报道了添加P₂O₅、TiO₂和ZrO₂的硅酸盐系统乳浊玻璃，这种玻璃在1020℃进行一定热处理后出现分相可造成乳浊效果，Shepilov M P等(参见文献：Shepilov M P，Kalmykov A E，Sycheva G A.Journal of Non-Crystalline Solids，2007，353：2415-2430.)报道的13.9Na₂O-36.0B₂O₃-50.1SiO₂(mol％)系统玻璃在1250℃即可熔融，在610℃左右进行热处理也会出现分相乳浊现象，王晓峰等(参见文献：王晓峰，汤华娟，王承遇，陶瑛.玻璃与搪瓷，2007，35(5)：36-42)从理论上阐述了无氟乳浊玻璃生产工艺的优缺点，指出分相乳浊、微晶乳浊和磷酸盐乳浊玻璃通常需要热处理才能产生理想的乳浊效果。但是利用热处理产生乳浊不利于玻璃的连续生产，同时也会增加玻璃的生产成本。到目前为止，国际上还未见利用玻璃分相原理来开发研究低磷、无氟且不需热处理的乳浊玻璃的报道。The mechanism of glass opacification mainly includes crystal grain opacification, phase separation opacification, unmelted particle opacification and micro-bubble opacification. At present, almost all manufacturers at home and abroad adopt the first opacification method, of which fluorspar and sodium fluorosilicate It is the most common opacifying agent. When the glass liquid is cooled, a large number of CaF ₂ and NaF grains are precipitated. Because the refractive index difference between these two grains and the matrix glass is large, the light is scattered and the opacification effect is caused. In recent years, there have been many reports using fluoride as an opacifying agent. Wang Ning et al. (see literature: Wang Ning, Tao Ying, Chen Min. Journal of Dalian Institute of Light Industry, 1999, 18(3): 16-19) introduced Al ₂ The effect of O ₃ content on the microstructure of fluoride opacified glass, Tian Fang (see literature: Tian Fang, Zhang Zhixia, Xie Zhiqiang. Glass and Enamel, 2003, 31(6): 30-32) and Pan Ling (see literature: Pan Ling, Li Haiying. Glass, 2004, 2: 47-48) respectively reported solutions to various defects in the production process of fluorine-containing opacified glass bottles. The content of fluoride in this kind of opacified glass is usually between 1 and 10wt%, which has the advantages of good opacifying effect and fast opacifying speed. Therefore, this kind of opacifying method is still mainly used in the production of opacifying glass at home and abroad. However, the shortcomings of this fluoride opacified glass are also very prominent. On the one hand, the fluoride will react as follows during the melting process: 4RF+SiO ₂ →2R ₂ O+SiF ₄ ↑, which is very serious for refractory erosion. Shorten the service life of the glass furnace; on the other hand, fluoride is easy to volatilize during the melting process, which is not conducive to the control of the degree of glass opacity. What is more serious is that the volatilization of fluorine is relatively harmful to the surrounding environment. The environmental pollution problem caused by discharge will inevitably increase the cost of the product; again, fluoride, as a toxic substance, makes this fluorine-containing glass difficult to be made into various tableware, etc., which limits its scope of application. The development of fluorine-free opacified glass has become a common concern of scholars and production technicians from all over the world. W etc. (see literature:

W, Frank M and Rheinberger V. Thermochimica Acta, 1996, 280-281: 491-499.) reported the addition of P ₂ O ₅ , TiO ₂ and ZrO ₂ silicate system opacified glass, this glass is at 1020 ℃ After a certain heat treatment, the phase separation can cause the opacity effect. Shepilov M P et al. ₂ O-36.0B ₂ O ₃ -50.1SiO ₂ (mol%) system glass can be melted at 1250 °C, and heat treatment at about 610 °C will also cause phase separation and emulsification, Wang Xiaofeng et al. (see literature: Wang Xiaofeng, Tang Huajuan, Wang Chengyu, Tao Ying. Glass and Enamel, 2007, 35(5): 36-42) theoretically expounded the advantages and disadvantages of the production process of fluoride-free opacified glass, and pointed out that phase separation opacification, microcrystalline opacification and phosphoric acid Salt opacified glass usually requires heat treatment to produce the desired opacifying effect. However, the use of heat treatment to produce opacification is not conducive to the continuous production of glass, and will also increase the production cost of glass. So far, there has been no report in the world on the use of the principle of glass phase separation to develop and research low-phosphorus, fluorine-free, and non-heat-treated opaque glasses.

Contents of the invention

The object of the present invention is to overcome the above-mentioned disadvantages of opal glass, and to prepare opaque glass with excellent mechanical, thermal properties and chemical stability, which is low in phosphorus, free of fluorine and does not require heat treatment.

A fluorine-free environment-friendly opaque glass, the glass material composition of which is SiO ₂ -Al ₂ O ₃ -B ₂ O ₃ -P ₂ O ₅ -MgO-CaO-SrO-BaO-Li ₂ O-Na ₂ OK ₂ O. The specific composition mass percentage is: SiO ₂ (58.5-61), Al ₂ O ₃ (4.0-5.2), B ₂ O ₃ (3.3-4.5), P ₂ O ₅ (6.7-7.5), MgO (0-3.6) , CaO (0-2.2) SrO (0-6), BaO (5.6-12.2), Li ₂ O (0-1.5), Na ₂ O (10.2-12.5), K ₂ O (0-4.6). The melting temperature of the glass is 1500-1520°C, heat preservation for 3 hours, and the annealing temperature is 550-560°C, heat preservation for 1 hour.

In the manufacturing method of the present invention, a small amount of phosphate is used to replace fluoride to produce opacification effect. In the industrial production of opacity glass, phosphate is introduced in the form of phosphate rock, which will not cause environmental pollution, and can avoid the pollution caused by fluorine. The glass furnace has short service life and safety problems. Using dense network structure reconstruction technology, adjusting the composition of SiO ₂ and P ₂ O ₅ network formers, and introducing alkali metal or alkaline earth metal oxides at the same time, the molten glass forms phosphate-rich salts with a size of 0.15-0.30 μm during the cooling process phase droplets, giving the glass a significant opacity effect. It does not contain common and expensive crystal nucleating agents such as TiO ₂ and ZrO ₂ , which can reduce the cost of the product. In addition, the opacity of the glass is produced by spontaneous phase separation, and no heat treatment is required, which can save energy. The introduction of an appropriate amount of B ₂ O ₃ can reduce the melting temperature of the glass and is also beneficial to enhance the opacification effect of the glass; in addition, the introduction of a small amount of Al ₂ O ₃ can make the glass network structure tend to be denser, which is beneficial to improve the chemical stability of the glass.

The density of the fluorine-free environment-friendly opaque glass material prepared by the method provided by the invention is 2.51-2.82 g·cm ^-3 , the thermal expansion coefficient between 25-300°C is 56.5-68.2×10 ^-7 °C ^-1 , and the resistance The bending strength is 79.3-96.2MPa, the whiteness is 78-86%, the water resistance measured by the standard DIN method is grade I-II, the acid resistance is grade III-III, and the alkali resistance is grade II-III. With good gloss, it is a kind of practical new glass material with wide application prospects.

The main properties of glass made by the present invention are as shown in table 1:

Table 1 Glass properties provided by the present invention

performance unit Products of the present invention Density g cm ^-3 2.51～2.82 Thermal expansion coefficient ×10 ^-7 ℃ ^-1 56.5～68.2 Bending strength MPa 79.3～96.2 BaiDu % 78～86 water resistance class I～II acid resistance class II～III Alkali resistance class II～III

Description of drawings

FIG. 1 is a photograph of the microstructure of the opacified glass in Example 1.

Detailed ways

Example 1:

Glass composition (wt%) is:

SiO ₂ Al ₂ O ₃ B ₂ O ₃ P ₂ O ₅ MgO CaO BaO Na ₂ O

SiO ₂ Al ₂ O ₃ B ₂ O ₃ P ₂ O ₅ MgO CaO BaO Na ₂ O

61 4 4.2 7 2.1 1.2 8 12.5

Use silicon dioxide, aluminum oxide, boric acid, diammonium hydrogen phosphate, magnesium oxide, calcium carbonate, barium carbonate, and sodium carbonate as raw materials, weigh and mix them evenly according to the above components, and then keep warm in an electric furnace at 1520°C for 3 After 1 hour, the molten glass is rapidly cooled in a mold to form a block glass, which is sent to an annealing furnace at 560°C for annealing, kept for 1 hour, and then cooled to room temperature to form a fluorine-free silicate opaque glass material. Its thermal expansion coefficient is 56.5×10 ^-7 ℃ ^-1 , its bending strength is 96.2MPa, and its whiteness is 84%. Other properties are shown in Table 1.

Example 2:

Glass composition (wt%) is:

SiO ₂ Al ₂ O ₃ B ₂ O ₃ P ₂ O ₅ SrO BaO Na ₂ O K ₂ O

60.5 4.2 3.3 7.2 6 5.6 11.2 2

Use silicon dioxide, aluminum oxide, boric acid, diammonium hydrogen phosphate, strontium carbonate, barium carbonate, sodium carbonate, and potassium carbonate as raw materials, weigh and mix them evenly according to the above components, and then keep warm in an electric furnace at 1520°C for 3 After 1 hour, the molten glass is rapidly cooled in a mold to form a block glass, which is sent to an annealing furnace at 560°C for annealing, kept for 1 hour, and then cooled to room temperature to form a fluorine-free silicate opaque glass material. Its thermal expansion coefficient is 58.7×10 ^-7 ℃ ^-1 , its bending strength is 90.3 MPa, and its whiteness is 86%. Other properties are shown in Table 1.

Example 3:

Glass composition (wt%) is:

SiO ₂ Al ₂ O ₃ B ₂ O ₃ P ₂ O ₅ MgO CaO BaO Li ₂ O Na ₂ O

60 4.2 4 7.2 2.1 2.2 7.8 1.5 11

Use silicon dioxide, aluminum oxide, boric acid, diammonium hydrogen phosphate, magnesium oxide, calcium carbonate, barium carbonate, lithium carbonate, and sodium carbonate as raw materials, weigh and mix them uniformly according to the above components, and then heat them in an electric furnace at 1510°C Keep warm in medium for 3 hours, quickly cool the molten glass in the mold to form block glass, send it to an annealing furnace at 560°C for annealing, keep it warm for 1 hour, and then cool to room temperature to form fluorine-free silicate emulsion glass material. Its thermal expansion coefficient is 61.3×10 ^-7 ℃ ^-1 , bending strength is 87.3MPa, and whiteness is 84%. Other properties are shown in Table 1.

Example 4:

Glass composition (wt%) is:

SiO ₂ Al ₂ O ₃ B ₂ O ₃ P ₂ O ₅ MgO CaO BaO Na ₂ O K ₂ O

59.5 4.3 4.5 7 1.7 1.5 8 12.5 1

Use silicon dioxide, aluminum oxide, boric acid, diammonium hydrogen phosphate, magnesium oxide, calcium carbonate, barium carbonate, sodium carbonate, and potassium carbonate as raw materials, weigh and mix them according to the above components, and then heat them in an electric furnace at 1510°C Keep warm in medium for 3 hours, quickly cool the molten glass in the mold to form block glass, send it to an annealing furnace at 560°C for annealing, keep it warm for 1 hour, and then cool to room temperature to form fluorine-free silicate emulsion glass material. Its thermal expansion coefficient is 65.1×10 ^-7 ℃ ^-1 , its bending strength is 84.6MPa, and its whiteness is 81%. Other properties are shown in Table 1.

Example 5:

Glass composition (wt%) is:

SiO ₂ Al ₂ O ₃ B ₂ O ₃ P ₂ O ₅ MgO BaO Na ₂ O

59 4.5 3.8 6.7 3.6 12.2 10.2

Use silicon dioxide, aluminum oxide, boric acid, diammonium hydrogen phosphate, magnesium oxide, barium carbonate, and sodium carbonate as raw materials, weigh and mix them evenly according to the above components, and then keep warm in an electric furnace at 1500°C for 3 hours. The melted molten glass is rapidly cooled in the mold to form a block glass, which is sent to an annealing furnace at 550°C for annealing, kept for 1 hour, and then cooled to room temperature to form a fluorine-free silicate opacified glass material. Its thermal expansion coefficient is 67.2×10 ^-7 ℃ ^-1 , its bending strength is 80.2 MPa, and its whiteness is 78%. Other properties are shown in Table 1.

Embodiment 6:

Glass composition (wt%) is:

SiO ₂ Al ₂ O ₃ B ₂ O ₃ P ₂ O ₅ MgO BaO Na ₂ O K ₂ O

58.5 5.2 3.6 7.5 1.8 7.5 11.3 4.6

Use silicon dioxide, aluminum oxide, boric acid, diammonium hydrogen phosphate, magnesium oxide, barium carbonate, sodium carbonate, and potassium carbonate as raw materials, weigh and mix them evenly according to the above components, and then keep warm in an electric furnace at 1500°C for 3 After 1 hour, the melted molten glass is rapidly cooled in a mold to form a block glass, which is sent to an annealing furnace at 550°C for annealing, kept for 1 hour, and then cooled to room temperature to form a fluorine-free silicate opaque glass material. Its thermal expansion coefficient is 68.2×10 ^-7 ℃ ^-1 , its bending strength is 79.3MPa, and its whiteness is 80%. Other properties are shown in Table 1.

Claims (2)

1. fluorin environment protection opaque glass material and manufacture method thereof, it is characterized in that: glass material consists of SiO ₂-Al ₂O ₃-B ₂O ₃-P ₂O ₅-MgO-CaO-SrO-BaO-Li ₂O-Na ₂O-K ₂O.The concrete mass percent of forming is: SiO ₂(58.5～61), Al ₂O ₃(4.0-5.2), B ₂O ₃(3.3-4.5), P ₂O ₅(6.7-7.5), MgO (0-3.6), CaO (0-2.2) SrO (0-6), BaO (5.6-12.2), Li ₂O (0-1.5), Na ₂O (10.2-12.5), K ₂O (0-4.6).

2. fluorin environment protection opaque glass material and manufacture method thereof, it is characterized in that: take by weighing raw materials such as silicon-dioxide, aluminium sesquioxide, boric acid, DAP, magnesium oxide, lime carbonate, Strontium carbonate powder, barium carbonate, Quilonum Retard, yellow soda ash, salt of wormwood by the described proportioning of claim 1, be mixed and made into uniform admixtion, admixtion is put into corundum crucible, after 1500～1520 ℃ of fusions are incubated 3 hours, casting was 550～560 ℃ of insulation annealings 1 hour.

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