JPS60161350A - Annular fluorescent lamp - Google Patents

Abstract

PURPOSE:To obtain the titled lamp having excellent lamp characteristics and hot workability by using a glass bulb consisting of SiO2, Al2O3, Na2O, K2O, Li2O, CaO, MgO, BaO, SrO, B2O3, As2O3, and Sb2O3 in specified composition. CONSTITUTION:An annular fluorescent lamp is obtained by using a glass bulb composed of 60-75% SiO2, 0.5-4% Al2O3, 12-17% Na2O, 0.3-3% K2O, and 0-1% Li2O (however O is not included, and Na2O+K2O+Li2O is regulated to 13-18.5%), and 1-8% CaO, 0.5-3% MgO, 0.1-3% BaO, 0.1-5% SrO, 0.1-3% B2O3, 0-0.6% As2O3 (however O is not included), and 0-0.5% Sb2O3 (however O is not included, and As2O3+Sb2O3 is regulated to 0.02-0.8%). The lamp has excellent initial luminous flux and maintenance of the luminous flux, and is inexpensive, light in weight, and small-sized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an annular fluorescent lamp, and more particularly to an annular fluorescent lamp in which the glass composition of the glass pulp forming the annular fluorescent lamp is improved to improve lamp characteristics.

[Technical background of the invention]

In general, annular fluorescent lamps are manufactured by coating the inner wall of an airtight container made of straight glass with a phosphor, sealing the stem holding the electrodes at both ends, and heating this in an electric furnace or the like to
The glass used to form this airtight glass container is softened by heating to 00°C and wound around a forming drum to form a ring shape. Conventionally, the glass used to form this glass airtight container has been made of lead oxide PbO for ease of heat processing during the ring forming process. Lead glass containing 4 to 28% by weight and having a low softening temperature was used.

Recently, with the aim of reducing weight and cost, attempts have been made to use glass pulp for straight tube fluorescent lamps and soda lime glass used for general lighting bulbs, and although some are already commercially available, there are still problems. A point is left.

[Problems with background technology]

Generally, glass that contains a large amount of PbO (hereinafter referred to as lead glass) requires a large amount of work environment maintenance costs to prevent environmental pollution caused by scattering of candy raw materials and volatilization of lead components during glass melting, molding, and processing. Moreover, there were disadvantages such as high raw material costs and heavy weight of the product itself.

For this reason, a switch has been made to soda-lime glass, which is cheaper and has a lower specific gravity. However, the heat processing temperature of soda-lime glass is 80 to 120°C higher than the lead glass mentioned above, resulting in a decrease in yield during processing. Of course, physical and chemical reactions occur between the phosphor and the binder and the glass tube, resulting in deterioration of the phosphor and a decrease in the initial luminous flux of the annular fluorescent lamp and deterioration of the luminous flux maintenance rate. A problem arose. Therefore, it is essential for glass for annular fluorescent lamps to have viscosity properties that allow easy bending, and the softening temperature is as low as possible, and the temperature properties of viscosity become loose near the working temperature. A material with a sharp viscosity curve and a wide working temperature range is desired.

In addition, the expansion coefficient is 91 to 103X in the temperature range of O to 300℃ due to the sealing property with stem glass using lead glass.
It is regulated to a range of 10/. Chemical durability is 8 mJi/N according to the Osaka Industrial Testing Laboratory method due to problems such as alkali precipitation caused by weathering during storage.
/100HCJ or less is required.

A fluorescent lamp using a glass composition that satisfies all of the above characteristics has not yet been developed.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an annular fluorescent lamp using a glass bulb made of soda-lime glass, with the aim of improving the lamp characteristics of initial luminous flux and luminous flux maintenance rate. .

[Summary of the Invention J] In order to achieve the above object, the present invention improves the lamp characteristics of an annular fluorescent lamp luxuriously and improves thermal processability by introducing a specific amount of SrO into conventional soda-lime glass. It has developed an excellent glass composition.

The initial luminous flux and luminous flux maintenance rate as lamp characteristics are the most important characteristics as working characteristics of a lamp. They found that chemical reactions had the greatest effect. That is, when SrO in glass is used in place of CaO+MyO, calcium halophosphate of the phosphor and binder (CaO1BaO1
B20. ) and the glass pulp tube wall. When molded into an annular shape at high temperatures, the phosphor and binder adhere to the tube wall of the glass pulp, causing a phenomenon called biting into the tube wall, which tends to deteriorate the working characteristics. However, it has been found that SrO has the effect of preventing this biting.

In addition, increasing the total amount of alkali oxides in soda-lime glass lowers the softening temperature and improves thermal processability, but on the other hand, chemical durability deteriorates and weathering occurs, and the expansion coefficient increases and stem 5) Due to the problem of sealing with glass, it is not possible to increase the amount significantly. For this reason, the present inventor fabricated a lamp using a glass bulb in which 5i02 and alkaline earth metals in soda-lime glass were partially replaced with SrO, and as a result, the following glass composition produced the best effect.

That is, Sigh 60-75%%AJ by weight percentage,
030, 5-4.0%, Ni7z012-17%, N2
00.2-3%, Li, 00-1% (however, 0 is not included,
And for N1720, the sum of 0, Li, and O is 13 to 18.
．． 51G), CaO 1-8%, M7o O, 5-3%,
BaOQ, 1-3%, 5rOQ, 1-5%, Btus
0 to 3%, As2O30 to 0.6% (contains O), 5b2o3θ to 0.5% (but does not contain O,
The sum of SzOa and 5btOs is 0.02 to 0.8%
) is an annular fluorescent lamp using a glass bulb having the composition:

Next, the reason for numerically limiting the above composition range will be explained in detail.

S i02 is one of the essential components for glass formation, but 6
If it is less than 0%, the expansion coefficient becomes high and chemical durability deteriorates, which is not preferable. If it exceeds 75%, the expansion coefficient becomes too low and the softening temperature becomes high, making it difficult to form a ring. Desirably it is 65 to 73%.

Afi20. If it is less than 0.5%, chemical durability deteriorates, and if it exceeds 4%, the glass becomes non-uniform and defects such as striae increase. It is preferably 1 to 3%. If the content of Na2O and O is less than the above lower limit, the softening temperature will be high, making the ring forming operation difficult, and the expansion coefficient will also be too low. Moreover, when the above-mentioned upper limit is exceeded, the expansion coefficient becomes large, and the chemical durability and electrical insulation properties decrease. Although i and two have a melting promoting effect even when added in small amounts, they are expensive, so they are limited to 1% or less.

The reason for setting the total amount of alkali oxides to 13 to 1&5% is the same as the reason for limiting the amount of Na2O and 0 described above.

Alkaline earth metal oxides such as CaO and MfO have the effect of improving electrical insulation and chemical durability, but
If CaO is less than 01% and M2O is less than 0.5%, no effect can be expected, and if CaO exceeds 8% or MP03%, the glass tends to devitrify, which is not preferable. Furthermore, although CaO and MoO have the effect of lowering the high temperature viscosity, they have the effect of increasing the viscosity within the working temperature range, so they are not preferred for the purpose of lowering the softening temperature. BaO has the effect of lowering the softening temperature, but 0.1
If it is less than 3%, no effect can be expected, and if it exceeds 3%, the tendency towards devitrification becomes large, which is not preferable.

As mentioned above, SrO is useful for preventing the phosphor and binder from biting into the tube wall of the glass pulp, and is also an essential component for improving bending workability and chemical durability. However, if it is less than 0.1%, the effect cannot be expected.
If it exceeds 5%, devitrification increases, which is not preferable.

B2O3 improves meltability and chemical durability, but if it is less than 0.1%, it has no effect, and if it exceeds 3%, it increases the softening temperature, which is not preferable. Al2O
Both 5h and 8bzOa are used as fining agents, and also have the effect of maintaining the molten glass in an oxidizing atmosphere and preventing coloring due to Fe 2+, but if the total amount is less than α02%, no effect can be expected, and 0, If it exceeds 8%, it will re-foam during heat processing, creating foam defects.

[Embodiments of the invention]

The present invention will be explained in detail below. Table 1 shows examples of the glass composition of annular fluorescent lamps according to the present invention and comparative examples with conventional products.

Comparative Example 1 is a conventional example of lead glass, and Comparative Example 2 is a conventional example of soda lime glass before improvement. Examples 1 to 6 are examples according to the present invention.

The expansion coefficient in Table 1 is the average coefficient of thermal expansion between 0 and 300°C, and the softening temperature is the temperature corresponding to a viscosity of 107.65 voids. and the values measured in accordance with JIS-3104 "Method for measuring softening temperature of glass" are shown. The working temperature was indicated by reading the temperature at a viscosity of 104 poise from a high temperature viscosity measurement curve. The water resistance was measured based on the Osaka Industrial Test New Method, and the amount of alkali eluted was used in neutralization titration.

Furthermore, Example No. 1 is a representative example among the above-mentioned examples.

Experimental 30W annular fluorescent lamps were manufactured using glass bulbs No. 1, No. 3, and No. 005, and the lamp characteristics were evaluated. Table 2 shows a comparison of lamp characteristics between the lamps manufactured in Examples No. 001, No. 13 and No. 35 and the conventional products of Comparative Examples No. 1 and No. 1 and No. 092.

As shown in Table 2, the annular fluorescent lamp using the example glass according to the present invention has significantly improved lamp characteristics compared to conventional soda lime glass, has a good yield in the manufacturing process, and has a stem The sealing properties between the glass and the glass bulb were good, and cracks and leak defects that occurred during the process were comparable to those of currently used glass.

Furthermore, the present invention is not limited to the above-described embodiments; based on the technical concept of improving lamp characteristics by introducing SrO, impurity components (for example, Fe, Pi), zr, etc. within a range that does not impair the lamp characteristics. etc.) may be mixed in small amounts.

〔Effect of the invention〕

As explained above, the annular fluorescent lamp using the glass pulp according to the present invention has improved lamp characteristics such as initial luminous flux and luminous flux retention. Concomitantly, it has many beneficial effects, such as improved moldability as a glass pulp, especially heat processability, and improved chemical durability.

Claims (1)

[Claims] 8i0z 60-75% by weight percentage, AjhOs 0
．． 5-4%, Nazo 12-17%, Kzo 0.3
~ 3%, Li2Oθ ~ 1% (however, 0 is not included, the sum of 0 and Li2O is 13~1 & 5% with N1720)
), Ca01-8%, MyOO, 5-3%, Ba0O0
1 to 3%, 5r00.1 to 5%, 3% to B2O50,
AS2030~0.6% (excluding O) 5bxO
1. An annular fluorescent lamp characterized in that a glass pulp having a composition of sO-0.5% (excluding 0, and the sum of AS203 and 8b203 is 0.02 to 0.8%) is used.