WO2013044721A1

WO2013044721A1 - Lead-free glass with very low sodium, and use thereof

Info

Publication number: WO2013044721A1
Application number: PCT/CN2012/080989
Authority: WO
Inventors: 潘佩聪
Original assignee: 上海亚明照明有限公司
Priority date: 2011-09-28
Filing date: 2012-09-05
Publication date: 2013-04-04
Also published as: CN102503124A

Abstract

Disclosed are a lead-free glass with very low sodium, and the use thereof. The lead-free glass with very low sodium has a sodium content of less than 0.5% but more than 0.23%, no As₂O₃ or Sb₂O₃, and a PbO content of less than 0.012%, thus being lead-free glass; and the CeO₂ content thereof in weight percent is not zero. The lead-free glass with very low sodium can be widely used in the preparation of a variety of electronic illuminants, such as the light tubes of fluorescent lamps or of energy-saving lamps.

Description

Very low sodium lead-free glass and application thereof

TECHNICAL FIELD The present invention relates to the field of energy-saving lamp light source materials, and relates to an ultra-low-sodium lead-free glass for energy-saving lamps (a glass material that meets environmental protection requirements and prevents ultraviolet radiation output) and an electronic device such as an energy-saving lamp or a fluorescent lamp. illuminator.

BACKGROUND OF THE INVENTION A low-pressure mercury discharge source, that is, a fluorescent light source, has been widely used in various civil lighting and professional lighting applications, and has become a necessity in daily life. From 1995 to 2010, low-sodium lead-free glass was widely produced and used, enabling the green harmlessness of fluorescent light sources. As the blister material of the light source, Na ₂ 0 of not less than 6.0% has been contained so far. The presence of sodium oxide keeps the lumen maintenance of fluorescent tubes high. In order to meet the high-end fluorescent lamp lumen maintenance requirements, it is generally used in the glass surface coated with eight _{_1,203} or Y ₂ 0 ₃ protective film method, the separated sodium oxide in the glass composition and elemental mercury lamp tube . On the one hand, the coating of the protective film increases the manufacturing cost of the lamp tube, and on the other hand, a new chemical element is introduced inside the lamp tube, which increases the chance of the impurity gas entering the lamp tube, resulting in a decrease in the quality of the lamp tube. A major effort in the fluorescent lamp industry for decades is: On the premise of maintaining the original low-sodium lead-free glass processing performance, the sodium content is reduced as much as possible, even to the absence of sodium. . Achieving a significant drop in the sodium content of the lamp glass is a major event in the lamp industry and a major measure to improve the quality of fluorescent lamps.

The following Chinese patents are similar or related to the present invention: 200410067162.3; 200410025374.5; 99118719.9; 99102177.0; 200510023944.1; 200610076538.6. The glasses referred to in the above patents all contain not less than 6.0% Na ₂ 0, both of which belong to the category of low sodium lead-free glass.

A very low sodium lamp glass is described in U.S. Patent 4,666,871, which has a sodium content of 0 to 1.3% by weight, but this glass contains 5% PbO, making the glass unusable in current domestic and international markets.

SUMMARY OF THE INVENTION An object of the present invention is to provide a very low-sodium lead-free glass material for a fluorescent lamp, an energy-saving light bulb case or other electron-emitting light tube, which has a sodium content of less than 0.5% but higher than 0.23%, so that a protective film is not required. Coating to achieve extremely high tube The effect of the maintenance rate of the light flux, and the selection of raw materials for glass manufacturing and the realization of lower raw material costs, which is beneficial to ensure that the material is close to the cost of the glass materials currently used in the industry, and promote the application of high-quality fluorescent lamps in domestic and foreign markets. . Another feature of the material is that the content of Ce0 ₂ is not less than 0.23%, in order to achieve the absorption of ultraviolet light by the glass material, and to ensure that the light source product prepared by the material meets the requirements of ultraviolet radiation safety. The PbO content of this material is not higher than 0.012%, which is in compliance with the laws and regulations on environmental protection in all countries of the world.

The very low sodium lead-free glass of the present invention comprises the following parts by weight:

Si0 ₂ 63-69 parts; preferably 63-66.4 parts;

A1 ₂ 0 ₃ 4.5-5 parts;

Na ₂ 0 0.25-0.5 parts; preferably 0.25-0.36 parts;

Li ₂ 0 3.0-3.7 parts;

K ₂ 0 11.8-12.2 parts;

CaO+ MgO 4.5-6.8 parts;

SrO 4.5-5.6 parts;

BaO 7.0-7.3 parts;

PbO 0-0.012 parts; preferably 0.011-0.012 parts

So ₃ 0.12-0.21 parts;

Fe ₂ 0 ₃ 0.015-0.03 parts;

Ce0 ₂ 0.23-0.31 parts.

The extremely low sodium content in the present invention means that the content of sodium oxide in the glass is less than 0.5% by weight, but higher than 0.23%; and the lead-free means that the content of lead oxide in the glass is less than 0.012% by weight. , that is less than 120ppm, even reaching lead-free.

The extremely low-sodium lead-free glass material of the invention meets the requirements of environmental protection, that is, meets the national standard requirement PbO<500ppm; the extremely low-sodium lead-free glass material of the invention has an inhibitory effect on ultraviolet radiation, and the content of Ce0 ₂ is not zero.

The extremely low-sodium lead-free glass of the present invention is compounded according to the chemical ratio of each component in the above-mentioned extremely low-sodium lead-free glass, and can be implemented on the original low-sodium lead-free glass manufacturing equipment. The raw material of the Si0 ₂ is a quartz sand having a purity of 99.9% or more, and the raw material of the Ce0 ₂ is a reagent grade product having a purity of 99.99%. The raw materials of the other components may be corresponding chemical reagents, and the purity is generally More than 99%.

The melting conditions of the very low sodium lead-free glass of the present invention are controlled as follows: The melting temperature is 1550-1700 ° C. Preferably, when the energy-saving lamp is prepared by using very low-sodium lead-free glass, the mixture is uniformly mixed according to the chemical ratio of each component in the ultra-low sodium lead-free glass, and the mixture is placed in the alumina crucible. In the electric heating Mafu furnace, the temperature is raised to 1700 ° C, and after 10 hours, it is lowered to 1550_ 1610 ° C, and the temperature is kept for 8-12 hours, and then slowly cooled to complete the production of the glass sample, wherein the cooling rate is 80 ° C / hour. Too fast a cooling rate will result in the formation of crystal grains in the glass and the inability to obtain a complete glass block. The glass tube used for the lamp needs to be completed in the glass melt by rotating the outer pull of the tube puller. The diameter of the glass tube and the thickness of the tube wall are determined by the pulling speed and the rotational speed. The temperature distribution inside the furnace and the temperature distribution at the outlet of the pull tube have a great influence on the physicochemical properties of the glass. The melting of the glass body is completed in an atmospheric atmosphere. The invention also provides an electron emitter prepared by using the above glass ultra-low sodium lead-free glass. The electron illuminator of the present invention refers to various light sources using glass as an outer sealing material. Preferably, the electron illuminator is a low-pressure mercury discharge lamp, and the air pressure in the tube or in the bubble is less than 10 torr when the low-pressure mercury discharge lamp is not lit at room temperature. More preferably, the low-pressure mercury discharge lamp is an energy-saving lamp or a straight tube fluorescent lamp. The energy-saving lamp tube is a straight tube type or various shaped bodies processed by a tube type, such as a straight tube (as shown in FIG. 1), a spiral tube and other shapes of tubes. The inner surface of the straight tube fluorescent lamp tube is coated with a phosphor capable of converting ultraviolet rays generated by gas discharge into visible light. The above phosphors are phosphors which can convert ultraviolet rays generated by gas discharge into various degrees of visible light in the prior art, and can be selected according to actual production needs. The extremely low-sodium lead-free glass for preparing the electron illuminant meets the national environmental protection requirement Rohs environmental protection standard, and the ultraviolet radiation output thereof is controlled within the scope of human safety, and conforms to GB/T 17263-2012 (energy-saving lamp integrated lamp) National standard) and European energy-saving lamp EUP / ERP light source product standards.

The extremely low-sodium lead-free glass of the invention has an extremely low sodium content of less than 0.5% but greater than 0.23%, which greatly improves the lumen maintenance rate of the lamp during use, and minimizes the light decay of the lamp. Therefore, the lamp can be filled with a lower mercury content, which provides the necessary material basis for the preparation of the unsaturated mercury gas discharge lamp; at the same time, the cost of the glass material is within a reasonable range.

The decrease in the Na ₂ 0 content of the glass of the present invention is generally accompanied by a large increase in the content of Li ₂ 0 and K ₂ 0. Since lithium oxide is a very expensive material, the price of potassium oxide is also much more expensive than that of sodium oxide. Therefore, a reduction in the content of sodium oxide leads to an increase in the cost of the overall glass material. The extremely low sodium lead-free glass of the present invention has substantially the same amount of BaO as the low-sodium lead-free glass in the prior art, which ensures that the glass cost is flat on this item without changing the physical and chemical parameters of the glass.

The ultra-low sodium lead-free glass of the invention has a viscosity change curve with temperature which is basically consistent with the low-sodium lead-free glass in the prior art, so the glass is applied in the field of fluorescent lamp or energy-saving lamp manufacturing in the prior art. no problem.

The extremely low-sodium lead-free glass of the present invention does not contain As ₂ 0 ₃ and Sb ₂ 0 ₃ , and the PbO content is extremely small, less than 0.012%, and is lead-free glass, and the glass material conforms to the Rohs environmental standard.

The very low sodium lead-free glass of the present invention can greatly improve the lumen maintenance of the lamp during use, minimizing the light decay of the lamp. Very low sodium lead-free glass will be a must-have material for a new generation of high-end fluorescent lamps. When using this glass to prepare fluorescent lamps or energy-saving lamps, the use of glass protective film coatings can be avoided, saving cost and reducing the difficulty of phosphor coating.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view of a light-emitting lamp, wherein 1 is a glass tube outer casing, 2 is a guide wire, 3 is a filament, 4 is a phosphor coating, and 5 is a cathode sputter.

The invention is further illustrated by the following examples, which are intended to illustrate the invention and not to limit the scope of the invention. The composition of the glass of Example 1-2 is shown in Table 1. In the very low-sodium lead-free glass raw materials of Examples 1 and 2, SiO _{2 is} made of 99.9% quartz sand as a raw material, and Ce0 _{2 is} a reagent grade product. The purity is up to 99. 99%, and the raw materials of other components can be corresponding chemical reagents, and the purity is generally above 99%. The preparation conditions of the extremely low-sodium lead-free glass of Examples 1 and 2 are as follows: After the chemical composition of the components in the ultra-low sodium lead-free glass is uniformly mixed, the mixture is placed in an alumina crucible, first The temperature was raised to 1700 ° C, and after 10 hours, it was lowered to 1550-1610 ° C, kept for 10 hours, and then slowly cooled to complete the production of the glass sample, wherein the rate of temperature drop was 80 ° C / hour. Too fast a cooling rate will result in the formation of crystal grains in the glass and the inability to obtain a complete glass block. The glass tube used for the lamp needs to be completed in the glass melt by rotating the outer pull of the tube puller. The diameter of the glass tube and the thickness of the tube wall are determined by the pulling speed and the rotational speed. Furnace temperature distribution and pull tube The temperature distribution at the outlet has a great influence on the physicochemical properties of the glass. The melting of the glass body is completed in an atmospheric atmosphere. The lime material glass of Comparative Example 1 and the light lead glass of Comparative Example 2 are all from the "Electric Light Source Technology" (Volume 1), by: Fang Daoqi / Cai Zuquan, Fudan University Press. The low sodium lead-free glass component of Comparative Example 3 was derived from Chinese Patent 97101817.6, 01132297.7 or 01134245.5. The glass compositions and properties of Examples 1-2 and Comparative Examples 1-3 are shown in Table 1. Among them, the coefficient of linear expansion in Table 1 is determined according to the SJ689 test standard, and the softening point is determined according to the SJ690 test standard. The sample density is calculated directly based on the weight and volume values.

Table 1

Density (Kg/dm ³ ) 2.6 2.64 2.5 2.82 2.62 Very low sodium lead-free glass in Table 1 and high soda glass (lime) / medium sodium glass (light lead) / low sodium glass (low in the comparative example) Sodium lead-free material), it can be seen that in the very low sodium lead-free glass of Examples 1 and 2, the proper sodium oxide content, PbO content and CeO ₂ content make the extremely low sodium lead-free glass of the present invention greatly improve the lamp tube The light flux maintenance rate during use minimizes the light decay of the lamp tube, and the use of the glass to prepare a fluorescent lamp or an energy-saving lamp can avoid the use of the glass protective film coating, thereby achieving cost saving and reducing the difficulty of phosphor coating. Therefore, the extremely low-sodium lead-free glass of the present invention has excellent performance and low cost, and meets the practical requirements of a new generation of high-end fluorescent lamp materials. Various electron illuminants such as a luminescent lamp as shown in Fig. 1 can be prepared by using the extremely low-sodium lead-free glass of Example 1 or 2.

Claims

The claim is a very low sodium lead-free glass comprising the following parts by weight:

Si0 ₂ 63-69 parts;

A1 ₂ 0 ₃ 4. 5-5 parts;

Na ₂ 0 0. 25-0. 5 parts;

Li ₂ 0 3. 0-3. 7 parts;

K ₂ 0 11. 8-12. 2 parts;

CaO and 卩 MgO 4. 5-6. 8 parts;

SrO 4. 5-5. 6 parts;

BaO 7. 0-7. 3 parts;

PbO 0-0. 012 copies;

S0 ₃ 0. 12-0. 21 copies;

Fe ₂ 0 ₃ 0. 015-0. 03 parts

Ce0 ₂ 0. 23-0. 31 copies. The very low sodium lead-free glass according to claim 1, wherein said very low sodium lead-free glass comprises the following components in a percentage by weight:

Si0 ₂ 63. 5-66. 5 parts;

A1 ₂ 0 ₃ 4. 5-5 parts;

Na ₂ 0 0. 25-0. 36 parts;

Li ₂ 0 3. 1-3. 7 parts;

K ₂ 0 11. 8-12. 12 parts;

CaO and 卩 MgO 4. 5-6. 8 parts;

SrO 4. 5-5. 6 parts;

BaO 7. 1-7. 3 parts;

PbO 0. 011- 0. 012

S0 ₃ 0. 12-0. 21 copies;

Fe ₂ 0 ₃ 0. 015-0. 03 parts; Ce0 ₂ 0. 23-0. 31 copies.

The ultra-low sodium lead-free glass according to claim 1 or 2, wherein the extremely low-sodium lead-free glass does not contain As ₂ 0 ₃ and Sb ₂ 0 ₃ , and the weight percentage of PbO is less than 500ppm.

4. An electroluminescent body prepared from the very low sodium lead-free glass according to claim 1 or 2.

The electroluminescent body prepared by using the extremely low-sodium lead-free glass according to claim 4, wherein the electron emitter is a low-pressure mercury discharge lamp, and the low-pressure mercury discharge lamp is not lit at room temperature The pressure inside the tube or inside the bubble < 10torr.

The electroluminescent body prepared by using the extremely low-sodium lead-free glass according to claim 5, wherein the low-pressure mercury discharge lamp is an energy-saving lamp or a straight tube fluorescent lamp.

The electron emitter according to claim 6, wherein the energy-saving lamp tube is a straight tube type or a tube shaped machine.

The electron illuminator prepared by the ultra-low sodium lead-free glass according to claim 6, wherein the inner surface of the straight tube fluorescent lamp tube is coated with a phosphor capable of converting ultraviolet rays generated by gas discharge into visible light.

The electroluminescent body prepared by using the extremely low-sodium lead-free glass according to any one of claims 4-8, wherein the extremely low-sodium lead-free glass for preparing the electron illuminant conforms to the Rohs environmental standard, and the ultraviolet ray thereof The radiation output complies with the national standard GB/T 17263-2012 and the European energy-saving lamp EUP/ERP light source product standard.