CN110563329A

CN110563329A - Light diffusion glass

Info

Publication number: CN110563329A
Application number: CN201910970462.9A
Authority: CN
Inventors: 彭寿; 杨京安; 杨镇远
Original assignee: China Building Material Tongcheng New Material Co Ltd
Current assignee: China Building Material Tongcheng New Material Co Ltd
Priority date: 2019-10-13
Filing date: 2019-10-13
Publication date: 2019-12-13

Abstract

The invention discloses light diffusion glass, which comprises basic components of common soda-lime-silicate glass, wherein the content of sodium oxide in the basic components of the common soda-lime-silicate glass is reduced by 1.5-2.8 wt%, and a new component of barium oxide with the weight percentage of 0.5-1 wt% is added. Compared with the prior art, the invention processes on the premise of not changing the existing rolled glass production line equipment, reduces the sodium oxide content in the components of the common soda-lime-silicate rolled glass, increases the barium oxide component, has better light transmittance, good chemical stability, high thermal shock resistance, hardness, wear resistance and high strength than the ultra-white rolled glass, and more importantly increases the light scattering and transmission, shields a luminous source and a glaring light source, and simultaneously enables the light penetrating through the glass to be softer and more uniform, thereby achieving the opaque and comfortable light transmission effect.

Description

Light diffusion glass

Technical Field

The invention relates to the technical field of glass production and processing, in particular to light diffusion glass.

Background

about 210 million hectares of greenhouses (wherein: 137 million hectares of a first generation of plastic greenhouse and 73 million hectares of a second generation of common glass greenhouse) exist in China by 2017, and the greenhouses are small in single body scale, large in occupied area (low in land utilization rate), poor in daylighting performance, low in mechanized cultivation technical level, low in risk of resisting natural disasters and plant diseases and insect pests, severe in planting environment and serious in edible environment-friendly problem. In order to further meet the requirement of people on pollution-free and health-care food consumption, a third-generation greenhouse, namely a sunlight organic plant factory greenhouse workshop adopting the Dutch greenhouse agriculture and Israel planting technology, is developed at home.

The sunlight plant factory collects sunlight into an oversize sunlight room (greenhouse workshop) which is built by using light functional glass and has the size of about 7 hectares per monomer, and carries out high-precision control operation on the environment in the greenhouse in a factory operation mode, thereby realizing high-efficiency facility agriculture for annual continuous production of crops. It is a production form of modern agriculture, is not or rarely restricted by natural environment, and is internationally recognized as one of important marks for measuring the high technical level of national agriculture. Compared with the traditional greenhouse, the sunlight plant factory has the advantages of large scale, high automation degree, high production efficiency, good controllability and the like, and is the inevitable direction of agricultural modernization transformation in China.

The crop yield is 90-95% from photosynthesis of crop leaves, and 5-10% from nutrient absorbed by crop roots. Therefore, how to increase the light energy utilization rate of crops and produce more photosynthetic products is a fundamental problem for increasing the yield of crops. Therefore, the quantity and the intensity of the illumination entering the greenhouse workshop directly relate to the production efficiency and the benefit of the sunlight plant factory, and the light-transmitting substances which can enable the sunlight to well enter the workshop and efficiently utilize and regulate the solar spectrum components become the key materials of the greenhouse plant factory, and the key materials are not glass and are not the genus Morus.

at present, the transparent material commonly used in glass greenhouses in China is common flat glass, the light transmittance of the transparent material is about 87%, although the transparent material is much higher than the light transmittance of a plastic film material commonly used in a plastic greenhouse, the transparent material is still lower than the light transmittance of light functional glass, meanwhile, the direct light of the common flat glass greenhouse is much, the light shadow and the light burn of a steel beam framework of the greenhouse structure exist, and the transparent material has great influence on the growth of crops. Foreign plant factories usually adopt light functional glass to construct greenhouses to regulate and control sunlight, the light transmittance in the greenhouses is high, light transmission is not in a fixed direction, no shadow is generated indoors, the plants can be irradiated at multiple angles, the indoor illumination condition can be effectively improved, the photosynthesis of crops is promoted, and the crop yield is improved; the glass can also reduce the direct radiation intensity of sunlight, and reduce the photoinhibition effect of plants. Practice proves that compared with the common flat glass greenhouse, the plant factory adopts the optical function glass with high light transmittance and moderate illumination intensity, and the crop productivity can be increased by 20-25%.

To encourage investment in plant factories, the state has recently developed a series of supporting policies: preferentially encouraging the continuous development and the large-scale construction of the modern agricultural standardized demonstration park; preferentially supporting the construction of high-efficiency agricultural planting and raising bases. The greenhouse planting of plant factories becomes an important facility agriculture for the transformation of agriculture and the replacement of greenhouses in China, and the demand of light function glass suitable for the greenhouse of the plant factories is multiplied.

Therefore, the invention provides the light functional glass with high light transmission and high haze (high scattering), namely the light diffusion glass, to replace the plastic film and the flat glass used in the existing greenhouse, meet the increasing demand of sunlight plant factories, and provide the yield-increasing and efficiency-improving assistance for modern facility agriculture in China, which is the main purpose of the patent.

Light diffusion principle of light diffusion glass: when light passes through the rolled glass substrate and encounters a special pattern pressed on the surface of the glass and a diffusion layer consisting of the light diffusing agent in the glass, the propagation direction of the light can be changed due to the uneven pattern and the difference between the refractive index of the material of the light diffusing agent and the refractive index of the substrate. Different patterns and different light diffusion dose change light directions. When light passes through the glass, the phenomena of multi-angle and multi-direction refraction, reflection and scattering occur, so that light diffusion is promoted, and light scattering and transmission are increased. The light diffusion glass can shield dazzling sunlight, simultaneously can enable light penetrating through the glass to become bright and soft, basically does not influence the light transmittance of the glass, achieves the comfortable effect of light transmission and opaqueness, and provides a uniform surface light source for displaying illuminated objects.

Besides the properties of common flat glass, the basic properties of the light diffusion glass also show the following aspects:

1. High light transmittance of glass

For ultra-white light diffusing glasses, iron oxide is the glass constituentThe impurities (2) mainly affect the light transmittance of the glass. In order to produce ultra-white light diffusion glass, raw materials with low iron content are selected, oxide raw materials are added, and the redox atmosphere in a kiln is controlled when batch materials are melted. When the glass contains 0.01 to 0.015 percent of ferric oxide and Fe²⁺the glass appears bluish green and the transparency of the glass is reduced. Due to Fe²⁺Specific to Fe³⁺The coloring ability is 10 times higher, and in order to improve the glass transmittance under the condition of the same content of iron oxide, the blue-green low-price iron (Fe) can be used²⁺) Oxidized to light yellow green high-valence iron (Fe)³⁺) Thereby reducing the coloring of the glass and improving the light transmittance.

2. Haze of glass

The haze of the glass is the phenomenon that after light enters the glass, part of the light is scattered, cloud mist is generated in the glass, and the glass is transparent and opaque. The main reason is that the carved patterns on the glass surface are related to the light diffusion agent containing barium oxide component which can change the light transmission direction. The refractive index of the light diffusing agent barium oxide is higher than that of other oxides, so that the refractive index of the glass is improved. The effect of various compositions on the refractive index of glass is roughly:

BaO1.98＞CaO1.84＞Al₂O₃1.765＞MgO1.70＞SiO₂1.45 > common glass 1.513

Different patterns and different light diffusion dose change light directions. When light passes through the glass, the phenomena of multi-angle and multi-direction refraction, reflection and scattering occur, so that light diffusion is promoted, and light scattering and transmission are increased.

3. Chemical stability of glass

In the production of soda-lime-silicate glass, a certain amount of Na is added to the glass ingredients to facilitate melting of the batch₂O, usually Na₂O is mainly introduced by using soda ash, the content of the O in the batch material occupies the second position, and Na in the conventional common soda-lime silicate glass₂The content of O accounts for 14-15 wt%, and the existing common soda-lime-silicate glass does not contain barium.

When the flat glass is used, the flat glass is corroded by water, acid, alkali, salt and other chemical gases, so that iridescence and white fog spots appear on the surface of the glass and the glass becomes dull, the luster and the attractiveness of the glass are influenced, the light transmittance is mainly reduced, the use is influenced, and the glass is scrapped due to the fact that the glass is adhered to each other. The resistance of glass to these attacks is known as chemical stability.

The attack of water or moisture (humidity) on glass is the most common one in daily life, and the attack mechanism is as follows: some ions on the glass surface adsorb water molecules in the atmosphere, which are OH-bonded^—The ionic groups form a film layer on the surface of the glass, if NaO and K are in the chemical composition of the glass₂When the content of O is small, the film does not develop after the formation of the film, and if the glass chemical composition contains a large amount of alkali hydroxide, the adsorbed water film becomes a solution of alkali hydroxide, and further absorbs moisture, and the glass surface is damaged. Meanwhile, the released alkali is continuously accumulated on the surface of the glass, the concentration is higher and higher, the pH value is rapidly increased, and finally, the corrosion to the glass is aggravated. The chemical reaction formula is as follows:

﹝O₃Si﹞—O—Na⁺ + H₂O =﹝O₃Si﹞—OH + NaOH

﹝O₃Si﹞—OH + 3/2 H₂O = Si(OH)₄

Si(OH)₄ + NaOH = ﹝Si(OH)₃O﹞Na + H₂O

in order to slow down the rate of water attack of the glass to a stop, on the one hand, in a certain thickness within the film, Na is required to be deficient⁺Ions, on the other hand with Na⁺The content of other components such as alkaline earth metal or other divalent metal ions is reduced, and the content of the divalent cations to Na is relatively increased⁺The "suppression effect" (blocking effect) of the ions is enhanced, thereby causing H⁺ - Na⁺The ion exchange is slow, the first reaction hardly proceeds in the surface layer of the glass, so that the second and third reactions stop successively, as a result, the amount of the glass dissolved in water vapor (moisture) hardly increases, and the water attack on the glass stops。

From the above, it can be seen that the light diffusion glass can overcome the defects of low glass transmittance, no haze, poor chemical stability and the like of the common soda-lime-silicate glass.

Disclosure of Invention

The invention aims to solve the defects that the common plate glass for the second-generation greenhouse in the prior art has low light transmittance and is easy to cause light burn to plants due to light shadow and direct light, and provides the light diffusion glass containing barium silicate with low sodium and low iron to solve the problems.

In order to achieve the purpose, the technical scheme of the invention is as follows:

A light diffusion glass comprises the basic components of ordinary soda-lime-silicate glass, and is characterized in that: the content of sodium oxide in the basic components of the common soda-lime-silicate glass is reduced by 1.5-2.8 wt.%, and a new component of barium oxide with the weight percentage of 0.5-1 wt.% is added.

preferably, the paint comprises the following components in percentage by weight: SiO 2₂71.0 wt.%～73.0 wt.%、Al₂O₃0.9 wt.%～1.5 wt.%、Fe₂O₃0.009 wt.%～0.012 wt.%、CaO 8 wt.%～10 wt.%、MgO 2.5 wt.%～3.9 wt.%、Na₂O 12.5 wt.%～13.0 wt.%、BaO0.5 wt.%～1.5 wt.%、Sb₂O₃0.18 wt.% to 0.22 wt.%, the above components constituting the light diffusing glass;

The light diffusion glass is prepared from the following raw materials in percentage by weight: 59-62 wt% of silica sand, 16.5-17.0 wt% of soda ash, 4-7 wt% of calcite, 8-15 wt% of dolomite, 0.85-1.5 wt% of aluminum powder, 1.0-2.0 wt% of barium carbonate and 1.2-1.5 wt% of composite clarifier.

Preferably, the light diffusion glass comprises the following components in percentage by weight: SiO 2₂73.6 wt.%、Al₂O₃1.4 wt.%、Fe₂O₃0.01 wt.%、CaO 8.21 wt.%、MgO 2.5 wt.%、Na₂O 12.9 wt.%、BaO 1 wt.%、Sb₂O₃0.18 wt.%、SO₃0.2 wt.%；

The light diffusion glass is prepared from the following raw materials in percentage by weight: 60.8 wt.% of silica sand, 17.2 wt.% of soda ash, 7 wt.% of calcite, 10 wt.% of dolomite, 1.5wt.% of aluminum powder, 2.0 wt.% of barium carbonate and 1.5wt.% of composite clarifier.

Preferably, the paint comprises the following components in percentage by weight: SiO 2₂72.30 wt.%～73.5 wt.%、Al₂O₃1.0 wt.%～1.5 wt.%、Fe₂O₃0.08 wt.%～0.12 wt.%、CaO 8.3 wt.%～8.5 wt.%、MgO 3.8 wt.%～4.0 wt.%、Na₂O plus K₂O 13 wt.%～14 wt.%、BaO0.5 wt.%～1.0 wt.%、SO₃0.2 wt.%, the above components constituting float glass;

the float glass is prepared from the following raw materials in percentage by weight: 59-60 wt% of silica sand, 16.5-17.5 wt% of soda ash, 5-8 wt% of limestone, 10-15 wt% of dolomite, 4-6 wt% of feldspar, 1.0-2.0 wt% of barium carbonate and 0.8-1.2 wt% of mirabilite.

Preferably, the float glass comprises the following components in percentage by weight: SiO 2₂72.52 wt.%、Al₂O₃1.0 wt.%、Fe₂O₃0.08 wt.%、CaO 8.3 wt.%、MgO 3.8 wt.%、Na₂o plus K₂O 13.1 wt.%、BaO1.0 wt.%、SO₃0.2 wt.%；

the float glass is prepared from the following raw materials in percentage by weight: 59 wt.% of silica sand, 17 wt.% of soda ash, 6.8 wt.% of limestone, 9 wt.% of dolomite, 5wt.% of feldspar, 2.0 wt.% of barium carbonate and 1.2 wt.% of mirabilite.

The invention is simple and practical, and can be directly used on a rolled glass production line without modification. The ultra-white rolled glass produced by the method has the advantages of improving chemical stability, thermal stability, mechanical strength and hardness, completely meeting the use requirements of customers, being particularly used for glass greenhouses, and having the effects of high solar light transmittance, no roof truss shadow, moderate illumination intensity and increasing the crop yield by 20-25%.

Compared with the common soda-lime-silicate plate glass product, the invention has the following advantages:

a. The refractive index of the glass is 1.98 higher than that of soda-lime-silicate glass 1.513 due to the addition of barium oxide component in the glass, wherein the main components of silicon oxide 1.45, calcium oxide 1.84, magnesium oxide 1.70 and aluminum oxide 1.765 change the propagation direction of light. When light passes through the glass, the light is refracted for countless times, so that the light diffusion, namely the light uniformization effect is achieved, and the light becomes softer.

b. because the upper surface and the lower surface of the glass are pressed with different patterns, light rays are refracted, reflected and scattered in multiple angles and directions when passing through the glass, so that the light is promoted to be diffused, and then cloud haze is generated in the glass, and the effects of light transmission, opacity and comfort are achieved. When the light diffusion glass is used on a greenhouse, not only can the shade of a roof truss be eliminated, but also the light irradiation intensity can be reduced, and the burning of the plants by light can be reduced.

c. Because the barium oxide component is added in the glass, the strength and hardness of the material of the glass are higher, so that the strength and hardness of the glass can be improved, and the scratch resistance of the glass is better.

d. The use amount of the soda ash is reduced, so that the risk of unstable chemical performance (glass mildewing) of the glass caused by the separation of Na + ions in use can be effectively reduced, and compared with the prior art, the glass produced by the method can not be easily corroded like common soda-lime silicate plate glass when used in large regions such as water vapor, high temperature, humidity, salt and the like in coastal regions, southern regions and the like.

Detailed Description

In order to provide a further understanding and appreciation for the structural features and advantages achieved by the present invention, the following detailed description of the preferred embodiments is provided:

The invention does not change the existing production line equipment for producing the ultra-white rolled glass and carries out production and processing on the premise of not increasing energy consumption basically. The invention designs the ratio of various materials in the batch according to the glass components, reduces the dosage of soda ash, and adds barium carbonate.

Adjusting a melting clarification temperature schedule during production: when the batch materials are melted in the melting furnace, the melting process of the batch materials becomes slightly different from the melting of the soda-lime-silicate glass without barium carbonate because the added barium carbonate in the batch materials has fluxing and clarifying effects.

The change process of barium carbonate in melting: barium carbonate is decomposed violently at 1450 ℃, carbon dioxide is released, barium oxide is formed, and the glass liquid is clarified rapidly:

BaCO₃→ BaO+CO₂↑

The BaO has the similar action in the glass as CaO and MgO, and can increase the mechanical strength, the gloss and the chemical stability of the glass.

The low-sodium low-iron barium-containing silicate glass provided by the invention comprises basic components of common glass, wherein the content of sodium oxide in the low-sodium low-iron barium-containing silicate glass is reduced by 1.5-2.8 parts by weight on the basis of the basic components of the common glass, and a new component barium oxide of 0.5-1 part by weight is added.

In a first embodiment, the low-sodium low-iron barium-containing silicate glass comprises the following ultra-white rolled glass composed of the following components in percentage by weight:

Composition (I)

SiO₂

Al₂O₃

Fe₂O₃

CaO

MgO

Na₂O

BaO

Sb₂O₃

SO₃

Content (wt.%)

71.0～73.0

0.9～1.5

0.0090～0.012

8～10

2.5～3.9

12.5～13.0

0.5～1.5

0.18～0.22

0.20

The ultra-white rolled glass is prepared from the following two raw materials in percentage by weight:

Material(s)

Silica sand

Soda ash

Calcite

Dolomite

aluminum powder

Barium carbonate

Composite clarifying agent

ratio (wt.%)

59～62

16.5～17.0

4～7

8～15

0.85～1.5

1.0～2.0

1.2～1.5

Or

Material(s)

Silica sand

soda ash

calcite

Dolomite

aluminum powder

Barium carbonate

Composite clarifying agent

Ratio (wt.%)

59～62

16.5～17.0

4～7

8～15

0.85～1.5

2.0～3.0

1.2～1.5

In the second embodiment, the ultra-white rolled glass comprises the following components in percentage by weight:

Composition (I)	SiO₂	Al₂O₃	Fe₂O₃	CaO	MgO	Na₂O	BaO	Sb₂O₃	SO₃
										Content (wt.%)	72.6	1.5	0.01	8.21	2.5	12.9	1.0	0.18	0.2

Material(s)	Silica sand	Soda ash	Calcite	Dolomite	Aluminum powder	Barium carbonate	Composite clarifying agent
								Ratio (wt.%)	60.8	17.2	7	10	1.5	2.0	1.5

Or

Material(s)	silica sand	Soda ash	Calcite	Dolomite	Aluminum powder	Barium carbonate	Composite clarifying agent
								Ratio (wt.%)	60.8	17.2	6.5	9.5	1.5	3.0	1.5

In the third embodiment, the ultra-white rolled glass comprises the following components in percentage by weight:

Composition (I)	SiO₂	Al₂O₃	Fe₂O₃	CaO	MgO	Na₂O	BaO	Sb₂O₃	SO₃
										Content (wt.%)	73.0	1.44	0.01	8.21	3	13.1	0.5	0.18	0.2

Material(s)	Silica sand	Soda ash	Calcite	Dolomite	Aluminum powder	barium carbonate	Composite clarifying agent
								Ratio (wt.%)	61.8	17.2	7	10	1.5	1.0	1.5

Or

Material(s)	Silica sand	Soda ash	Calcite	dolomite	Aluminum powder	Barium carbonate	composite clarifying agent
								Ratio (wt.%)	61.8	17.2	6.5	9.5	1.5	2.0	1.5

In a fourth embodiment, the composition of the low-sodium low-iron barium-containing silicate glass comprises the following float glass consisting of the following components in percentage by weight:

Composition (I)

SiO₂

Al₂O₃

Fe₂O₃

CaO

MgO

Na₂O+K₂O

BaO

SO₃

Content (wt.%)

72.30～73.5

1.0～1.5

0.08～0.12

8.3～8.5

3.8～4.0

13.1～14

0.5～1.0

0.2

The float-rolled glass is prepared from the following two raw materials in percentage by weight:

Material(s)

Silica sand

Soda ash

Limestone

Dolomite

Feldspar

Barium carbonate

Natrii sulfas

Ratio (wt.%)

59～60

16～17.5

5～8

10～15

4～6

1.0～2.0

0.8～1.2

Or

Material(s)

Silica sand

Soda ash

Limestone

Dolomite

Feldspar

Barium carbonate

natrii sulfas

ratio (wt.%)

59～60

16～17.5

5～8

10～15

4～6

2.0～3.0

0.8～1.2

In the fifth embodiment, the float glass comprises the following components in percentage by weight:

Composition (I)	SiO₂	Al₂O₃	Fe₂O₃	CaO	MgO	Na₂O+K₂O	BaO	SO₃
									Content (wt.%)	72.52	1.0	0.08	8.3	3.8	13.1	1.0	0.2

Material(s)	Silica sand	Soda ash	Limestone	Dolomite	Feldspar	Barium carbonate	Natrii sulfas
								Ratio (wt. -%)）	59	16	6.8	10	5	2.0	1.2

Or

material(s)	Silica sand	Soda ash	Limestone	Dolomite	Feldspar	Barium carbonate	Natrii sulfas
								Ratio (wt.%)	59	16	6.8	9.5	4.5	3.0	1.2

In the sixth embodiment, the weight percentages of the float glass components in the fourth embodiment are as follows:

Composition (I)	SiO₂	Al₂O₃	Fe₂O₃	CaO	MgO	Na₂O+K₂O	BaO	SO₃
									Content (wt.%)	72.92	1.0	0.08	8.3	3.8	14	0.5	0.2

Material(s)	Silica sand	soda ash	limestone	dolomite	Feldspar	Barium carbonate	Natrii sulfas
								Ratio (wt.%)	59	17	6.8	10	5	1.0	1.2

Or

Material(s)	Silica sand	soda ash	Limestone	Dolomite	Feldspar	Barium carbonate	Natrii sulfas
								Ratio (wt.%)	59	17	6.8	9.5	4.5	2.0	1.2

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A light diffusion glass comprises the basic components of ordinary soda-lime-silicate glass, and is characterized in that: the content of sodium oxide in the basic components of the common soda-lime-silicate glass is reduced by 1.5-2.8 wt.%, and a new component of barium oxide with the weight percentage of 0.5-1 wt.% is added.

2. A light diffusing glass according to claim 1, wherein:

The paint consists of the following components in percentage by weight: SiO 2₂71.0 wt.%～73.0 wt.%、Al₂O₃0.9 wt.%～1.5 wt.%、Fe₂O₃0.009 wt.%～0.012 wt.%、CaO 8 wt.%～10 wt.%、MgO 2.5 wt.%～3.9 wt.%、Na₂O 12.5 wt.%～13.0 wt.%、BaO 0.5 wt.%～1.5 wt.%、Sb₂O₃0.18 wt.% to 0.22 wt.%, the above components constituting the light diffusing glass;

3. A light diffusing glass according to claim 2, wherein:

The light diffusion glass comprises the following components in percentage by weight: SiO 2₂73.6 wt.%、Al₂O₃1.4 wt.%、Fe₂O₃0.01 wt.%、CaO 8.21 wt.%、MgO 2.5 wt.%、Na₂O 12.9 wt.%、BaO 1 wt.%、Sb₂O₃0.18 wt.%、SO₃0.2 wt.%；

4. A light diffusing glass according to claim 1, wherein:

The paint consists of the following components in percentage by weight: SiO 2₂72.30 wt.%～73.5 wt.%、Al₂O₃1.0 wt.%～1.5 wt.%、Fe₂O₃0.08 wt.%～0.12 wt.%、CaO 8.3 wt.%～8.5 wt.%、MgO 3.8 wt.%～4.0 wt.%、Na₂O plus K₂O 13 wt.%～14 wt.%、BaO0.5 wt.%～1.0 wt.%、SO₃0.2 wt.%, the above components constituting float glass;

5. A light diffusing glass according to claim 4, wherein:

The float glass comprises the following components in percentage by weight: SiO 2₂72.52 wt.%、Al₂O₃1.0 wt.%、Fe₂O₃0.08 wt.%、CaO 8.3 wt.%、MgO 3.8 wt.%、Na₂O plus K₂O 13.1 wt.%、BaO 1.0 wt.%、SO₃0.2 wt.%；