JPH03171547A - Scattering preventive type fluorescent lamp - Google Patents

Abstract

PURPOSE:To prevent a deterioration of a high polymer resin and to improve the scattering preventive effect by forming an ultraviolet ray absorbing membrane and plural layers of transparent membranes which consist of high polymer resins with different expansion rates in order at the outer surface of a glass tube. CONSTITUTION:By a membrane 2 to absorb ultraviolet rays less than 400nm formed at the outer surface of a glass tube 1, a deterioration owing to the ultraviolet rays less than 400nm emitted from a fluorescent lamp furnishing a transparent membrane 3 of a high polymer resin with the expansion rate 200% or more and a transparent membrane 4 of a high polymer with the expansion rate less than 150% can be prevented. And since the lamp can stand a surface shock by the membrane 3, and can stand a spot shock by the membrane 4, the scattering preventive effect can be increased.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a novel shatterproof fluorescent lamp.

Since conventional fluorescent lamps use glass tubes, if the glass tubes are damaged due to improper handling, glass fragments may fly off and cause personal injury. As a method for dealing with this problem, a shatterproof type fluorescent lamp is known in which the outer surface of a glass tube is covered with a transparent tube made of a polymer resin such as polyester resin. This is a method in which a glass tube is covered with a heat-shrinkable polyester resin tube, and then the tube is heat-treated to form a polymer resin coating on the outer surface of the glass tube.

Problems to be Solved by the Invention In conventional shatterproof fluorescent lamps, tubes made of polyester resin are used in consideration of weather resistance, film strength, etc., as described above.

However, this tube is extremely expensive due to the difficulty of tube processing, and it requires an extremely inefficient process of manually covering the tube over a fully-used fluorescent lamp. The problem is that they are extremely expensive compared to general fluorescent lamps.

Therefore, the inventors first developed transparent anti-scattering resins such as organic solvent-soluble polyester polyol-based urethane resins and resins whose main component is a polyurethane water dispersion in which a urethane elastomer with a crosslinked structure is dispersed in water. We proposed an anti-scattering fluorescent lamp, which makes it extremely easy to form a protective coating and significantly reduces lamp costs compared to conventional lamps.However, as a result of further studies on high-load fluorescent lamps, we found that the polymer resin coating described above A problem has arisen in which the deterioration of

In addition, in the drop strength test, since the impact is a surface impact, the contact area of the impact against the fluorescent lamp is large, while in the impact resistance test, the impact area is small against the fluorescent lamp because it is a point impact, but When a molecular resin coating is used alone, there is a large difference in anti-scattering strength between drop strength tests and impact tests, resulting in the problem that the anti-scattering effect is weakened.

As a result of intensive research by the inventors regarding these issues, we found that the deterioration of the polymer resin coating is caused by
Free radicals are generated in the polymer that forms the transparent polymer resin by ultraviolet light of nm or less, and as this reaction progresses, the polymer crosslinks are broken one after another, resulting in a decrease in tensile strength and elongation, and the resin turns yellow. It became clear that it was colored.

The present invention has been made in order to solve the above problems, and it is easier to form a film than before, has good workability, prevents deterioration of the scattering prevention polymer resin, and is different from the conventional one. An object of the present invention is to provide a shatterproof fluorescent lamp that has an excellent shatterproof effect against impact.

Means for Solving the Problems In order to achieve this object, the shatterproof fluorescent lamp of the present invention has a coating on the outer surface of the glass tube that absorbs ultraviolet rays of 400 nm or less, and a polymer resin with an elongation rate of 200% or more. It has a structure in which a transparent film made of a transparent film made of a polymer resin of 150 percent or less is sequentially formed.

According to the present invention, by forming a coating on the outer surface of the glass tube that absorbs ultraviolet rays of 400 nm or less, the transparent coating of polymeric resin applied thereon can absorb ultraviolet rays of 400 nm or less emitted from fluorescent lamps. In addition to being able to prevent deterioration, by forming a transparent coating made of a large, soft polymer resin with an elongation rate of 200% or more on the coating, it can withstand surface impact. moreover,
By forming thereon a transparent film made of a small, hard polymer resin with an elongation rate of 150% or less, it can withstand point impact.

Example As a first step, the inventors fabricated shatterproof fluorescent lamps using transparent coatings made of polyurethane resin with different elongation rates on the outer surface of glass tubes, and conducted the following drop strength test. Table 1 shows the results of an impact test to check the scattering of glass pieces.

(Margins below) Table 1 As is clear from Table 1, the larger the impact contact area, the higher the elasticity of the polymer resin coating. It has also become clear that the smaller the impact contact area, the harder the polymer resin coating has no elasticity and is less than 150% of the elongation rate, contrary to the former.

Based on the above results, the inventors conducted the following experiment.

For the first layer, an organic solvent-based zinc oxide solution was used as the ultraviolet absorbing film. A 30-watt annular fluorescent lamp held horizontally was immersed in this solution, then pulled up and placed at a temperature of 70°C and a wind speed of 5 m/see. By drying with warm air, a transparent ultraviolet absorbing coating 2 made of zinc oxide is formed on the outer surface of the glass tube 1 to a thickness of 10 μm, as shown in FIG. Next, as a second layer, the fluorescent lamp held horizontally was immersed in 1500 gr of a polyurethane water dispersion (Superflex, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), and then lifted out and placed at a temperature of 100°C and a wind speed. Dry with hot air at 5 m/sec to form an elongation rate of 150 to 800 on the ultraviolet absorbing coating 2.
% polyurethane resin is formed to a thickness of 60 μm.

Then, as the third layer, polyurethane water dispersion 1500
After immersing the fluorescent lamp held horizontally in the gr liquid, it was pulled up and heated to a temperature of 100°C and a wind speed of 5 m/s.
A transparent film 4 made of polyurethane resin with an elongation rate of 100 to 200% is dried with 40 μm of e.g.
A shatterproof fluorescent lamp was obtained by forming the lamp to a thickness of .

In addition, in FIG. 1, 5 indicates a phosphor coating.

Using the fluorescent lamp obtained in this way, a drop strength test was conducted in which the fluorescent lamp was held horizontally and dropped naturally from a height of 3 m, and a 200 gr steel ball was attached to the end of a 1 m long string. Table 2 shows the results of an impact test in which the sample was exposed to a fluorescent lamp at an angle of 30 degrees from the vertical line.

(Left below) Table 2 As is clear from Table 2, an ultraviolet absorbing film is formed on the outer surface of the glass tube, and a large, soft polyurethane resin with an elongation rate of 200% or more is formed on top of the film. By forming a transparent film and adopting a three-layer structure with a transparent film made of a small, hard polyurethane resin with an elongation rate of 150% or less on top of the film, glass tubes were Although it was damaged,
The coating was not damaged and the glass pieces were firmly attached to the coating, so the glass pieces were protected by the coating and did not fly away.

Next, the coating was not damaged at all in the impact test.

Furthermore, when the lamp was lit for 5,000 hours as a life test, the fluorescent lamp according to the present invention did not turn yellow and was found to have no problems. However, in a fluorescent lamp in which the transparent coating 3 was simply formed on the outer surface of the glass tube 1 without having such an ultraviolet absorbing film 2, it was observed that the fluorescent lamp turned yellow after being lit for 1000 hours.

As described above, according to this embodiment, an ultraviolet absorbing coating 2 is formed on the outer surface of a glass tube 1, and a transparent coating 3 made of a large, soft polyurethane resin with an elongation rate of 2.00% or more is further formed on this coating. It has a three-layer structure in which a transparent film 4 made of a small, hard polyurethane resin with an elongation rate of 150% or less is formed on this film, significantly reducing the cost by half or less compared to conventional methods. can be reduced.

Effects of the Invention As explained above, the present invention provides a coating of 400% on the outer surface of the glass tube.
A coating that absorbs ultraviolet rays of nm or less is formed, and a transparent coating made of a polymer resin with an elongation rate of 200% or more is formed on the coating, and a transparent coating made of a polymer resin with an elongation rate of 1% or more is formed on the coating.
By forming a transparent coating made of a small, hard polymer with a size of 50 percent or less, it is much easier to form a shatterproof coating on glass tubes than before, and the material costs are also low, making it possible to reduce costs compared to conventional methods. It is possible to provide an anti-scattering type fluorescent lamp which can significantly reduce the amount of heat generated compared to the conventional one, has a greater anti-scattering effect, and can prevent deterioration of the anti-scattering polymer resin.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a shatterproof fluorescent lamp which is an embodiment of the present invention. 1... Glass tube, 2... Ultraviolet absorbing coating, 3... Transparent coating made of 200% or more soft polymer resin, 4... 150 Transparent film made of hard polymer resin of less than 5%
...phosphor coating.

Claims (1)

[Claims] A coating that absorbs ultraviolet rays of 400 nm or less is formed on the outer surface of the glass tube, then a transparent coating made of a polymer resin with an elongation rate of 200% or more is formed on the coating, and then a transparent coating is formed on the transparent coating. A shatterproof fluorescent lamp characterized by forming a transparent coating made of a polymer resin with an elongation rate of 150% or less.