KR900004821B1 - Fluorescent lamp - Google Patents

Abstract

Fluorescent lamp has a glass-tube outer surface coating of solvent- soluble fluorine-contg. polymer (I) incorporating a UV light absorbent (II). Pref. (I) is a fluoro-olefin-vinyl ether copolymer of intrinsic viscosity, measured in THE at 30 deg. C of 0.05-2.0 dl/g and contains 30-70 mol.% fluoro-olefin; 70-30 mole.% vinyl ether and no more than 30 mol.% hydroxyalkyl vinyl ether or glycidyl ether units. (II) is present to 0.5-30 pts. wt. based on 100 pts. wt. of (I), and the coatig layer is 5-200 microns thick.

Description

Fluorescent lamp

1 and 2 are spectral energy distributions of a typical fluorescent lamp according to the present invention.

3 is a spectral energy distribution diagram of a fluorescent lamp not coated with an ultraviolet absorber.

4 is a spectral energy distribution diagram of a fluorescent lamp coated with titanium oxide as an ultraviolet absorber.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to fluorescent lamps, and more particularly to so-called ultraviolet-free fluorescent lamps, which are lamps in which ultraviolet radiation is minimal.

Conventionally, light sources used as lighting in places where various exhibits are displayed, such as department stores, art galleries or museums, have been used to prevent fading of fluorescent displays (NU lamps) to prevent the exhibits from fading due to light. In order to prevent the fading by absorbing the short wavelength ultraviolet rays that cause the color fading, it has a two-layer structure in which acidic titanium (TiO ₂ ) is coated on the inner surface of the glass tube of the lamp and then coated with phosphor again.

However, it was pointed out that such NU lamps have the following drawbacks compared to lamps of the same type without titanium oxide coating.

(1) Low luminous flux (about 5% lower)

(2) Light colors are different.

(3) low color rendering.

(4) The manufacturing process is complicated.

Conventionally, in order to make up for the shortcomings of the NU lamp, the thickness of the titanium oxide coating layer has been reduced as much as possible. However, in this case, the UV absorption effect caused by the titanium oxide is lowered. There was a disadvantage.

In addition, Japanese Patent Application Laid-open No. 58-47058 contains an ultraviolet absorber on the inner circumferential surface of the glass tube of the NU lamp, and includes polyvinyl chloride, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, and toly-caprolactam. A method of applying a tubular heat-shrinkable film made of synthetic resins such as polyhexamethylene adiamide, polycarbonate or polymethyl methacrylate has been proposed. Since the amount of UV absorber is restricted in terms of compatibility, the thickness of the film to be applied must be increased to compensate for this, and the air layer formed between the glass and the coated film is not easy to completely remove. The amount of light passing through becomes insufficient, and the portion of the film coated on the glass tube And life, transparency, handling haneundedo the fluorescent lamp, as well as insufficient in performance such as heat resistance and weather resistance of the fluorescent lamp has a problem of making difficult.

The present inventors have continued research to compensate for the above drawbacks. As a result, a NU lamp containing a UV absorber and a solvent-soluble fluorine-containing polymer is applied to the outer wall of the glass tube of the NU lamp.

An object of the present invention is to provide a fluorescent lamp that is excellent in adhesion and lifespan, transparency, heat resistance and weather resistance, etc. of the film coated on the glass tube without actually generating ultraviolet radiation, and also easy in the manufacturing process.

Hereinafter, the present invention will be described in detail.

The fluorescent lamp according to the present invention is characterized by coating a soluble fluorine-containing polymer containing a ultraviolet absorber on the outer wall surface of the glass tube.

At this time, the solvent-soluble fluorine-containing polymer usefully used in the present invention has an intrinsic viscosity of 0.05 to 2.0 dl / g, preferably 0.07 to 0.8 dl / g in tetrahydrofuran at a temperature of 30 ° C. If it is lower than the above range, the mechanical strength of the coating is not good, and if it is high, the viscosity of the polymer composition increases, so that the concentration of the solution to be used tends to be low, and the workability of the polymer is also impaired. In addition, solvent-insoluble fluorine-containing polymers are not suitable because they cannot form a homogeneous film.

As the fluorine-containing polymer used in the present invention, those of addition polymers or axial polymers can be used. The fluorine-containing addition polymers include hydroxyl groups, epoxy groups, carboxyl groups, acid amide groups, ester groups, unsaturated bonds, and active hydrogens. Or an addition polymer or addition copolymer of a fluorine-containing unsaturated compound having a curing site such as halogen, and the condensation polymer system includes an epoxy resin, a fluorine-containing diol, a divalent basic acid, or a divalent basic resin having a fluorine-containing difunctional group. As condensation products of anhydrides or diisocyanates, those capable of forming ester bonds, urethane bonds or urea bonds can be used. In particular, considering that the fluorine-containing polymer is easy to obtain the weatherability and mechanical properties of the coating and the polymer, it is preferable that the fluorine-containing polymer is, for example, an addition polymer type such as a copolymer of a fluoroolefin and a hydrocarbon-based vinyl ether. The fluoroolefin-vinyl ether copolymer which is advantageously used in the present invention preferably contains 30 to 70 mol% and 70 to 30 mol%, respectively, based on fluoroolefin and vinyl ether.

At this time, tetrafluoroethylene or chlorotrifluoroethylene is suitable as the fluoroolefin component, and a vinyl ether component is an alkyl containing a linear, branched or cyclic alkyl group having 2 to 8 carbon atoms. Vinyl ether is suitable.

In addition, the copolymer should contain a comonomer moiety capable of providing 3 to 25 mole percent of the cured moiety. Examples of the comonomer capable of providing such a cured moiety include hydroxyalkyl-vinyl ether or glycidyl vinyl. Functional group-containing vinyl ethers such as ethers are suitable. In this case, the copolymer is prepared by causing a polymerization reaction such as a polymerization initiator or an ionizing radiation to act on the monomer mixture in a proportion in the presence or absence of a polymerization medium to cause a copolymerization reaction. When using a fluorine-containing polymer having a curing site, a curing agent such as a polyfunctional compound having reactivity with a curing site of the fluorine-containing polymer may be used in an amount of 0.1 to 100 parts by weight, preferably 100 parts by weight of the fluorine-containing polymer. Is blended in the range of 0.5 to 50 parts by weight, and in some cases, a suitable curing aid or curing catalyst may also be blended.

Particularly, when preparing a composition for forming a room temperature-curable film using a fluorine-containing polymer having a curing site in a hydroxyl group, polyisocyanate or metal alkoxides may be used as a curing agent, and generally thermosetting acrylic when preparing a composition for forming a thermosetting film. Melamine resin curing agents or urea resin curing agents or polybasic acid curing agents used in the table may be used.

In this case, examples of the melamine resin curing agent include butylated methylol, methylated methylol, and epoxy-modified methylol melamine resins, which may be appropriately selected and used within the range of 0 to 6, respectively, depending on the purpose. The degree of condensation may also be appropriately selected. Examples of the urea resin curing agent include methylated or butylated urea resins, and the polybasic acid curing agent includes long chain aliphatic dicarboxylic acids, aromatic polycarboxylic acids, anhydrides thereof, and block polyisocyanates. Can be used. In this case, when using a melamine resin curing agent or urea resin curing agent, the addition of an acidic catalyst may be accelerated curing. In the case of preparing a film-forming composition using a fluorine-containing polymer contained in an epoxy group, a polyamine, a polybasic carboxylic acid, a phenol or a polyhydroxy compound such as a phenol resin or a non-aromatic polyol can be used as a curing agent. have.

On the other hand, the ultraviolet absorber according to the present invention is generally 0.5 to 30 parts by weight, preferably 1 to 25 parts by weight per 100 parts by weight of the fluorine-containing polymer, when the amount of the ultraviolet absorber is less than the above range Since the thickness of the coating layer needs to be increased in order to achieve the anti-fading effect, as a result, the requirement of the fluorine-containing polymer is increased. Conversely, when the amount exceeds the above range, the absorbent flows out and the transparency of the film coating layer is reduced. This tends to lower the adhesion between the glass tube outer wall and the coating layer of the fluorescent lamp.

Thus, as the ultraviolet absorber that can be used in the present invention can be exemplified by known benzophenol-based and benzotriazole-based absorbent, it is preferable to use a benzotriazole-based infrared absorber in terms of absorbency.

In addition, the composition for forming a film containing the fluorine-containing polymer and the ultraviolet absorbent according to the present invention is preferably prepared in a solution form in view of construction properties, and the solvent used for the coating sufficiently dissolves the fluorine-containing polymer and the ultraviolet absorbent. However, it is recommended that the outer surface of the glass tube of the fluorescent lamp is not corroded, and considering the volatility, aromatic hydrocarbons such as xylene and toluene, alcohols such as n-butanol, esters such as butyl acetate, ketones such as methyl isobutyl ketone, and glycol ethers such as ethyl cellosolve. And saturated hydrocarbons such as n-hexane, ligroin, and mineral spir are preferably selected from two or more and used in combination.

The coating composition as described above provides a transparent film having excellent gloss according to the volatilization of the solvent. Such a coating composition can be used as a lacquer-type coating by itself, but in particular, there is a hardened portion in the fluorine-containing polymer and It is preferable to add the polyfunctional compound which can react with to a polymer as a component of a hardening | curing agent, and to use it as a curable coating material.

In the present invention, the thickness of the coating layer formed on the outer surface of the glass tube is appropriately 5 to 200 µm, preferably 10 to 60 µm, but when the thickness is thicker than the above range, the coating layer is not transparent. It is preferable to apply the coating film to have the same thickness as the above range because the effect of preventing the fading is reduced and the like, as well as the needle hole in the coating, and the scattering prevention effect of the glass fragments is reduced.

Such a coating composition is applied to the outer surface of the glass tube of the fluorescent lamp and a hard coating is formed as necessary to form a transparent coating.

Hereinafter, the present invention will be described in detail with reference to Examples.

Example 1

In the terpolymers of tetrafluoroethylene, cyclohexyl vinyl ether and hydroxybutyl vinyl ether, the molar ratios were 50:40:10 and the intrinsic viscosity measured in tetrahydrofuran at 30 ° C. was 0.42 dl / g. In a solution obtained by dissolving 4.5 parts by weight of a fluorine-containing polymer in 20 parts by weight of xylene, 0.5 parts by weight of 2-hydroxy-4-n-octoxybenzophenone, an ultraviolet absorber, and a polyisocyanate-based curing agent ("coronate EH"-Japanese polyurethane 0.83 parts by weight was added to make a homogeneous paint.

The chart prepared as described above was applied to the outer wall of the glass tube of the fluorescent lamp ("FL 20S.D"-manufactured by Tokoshibaura Denki Co., Ltd.) and then heated at 150 ° C. for 5 minutes to form a transparent film having a thickness of 30 μm. Was formed.

Example 2

Intrinsic viscosity measured in tetrahydrofuran at 30 ° C. with a molar ratio of 50: 15: 25: 10 for chlorotrifluoroethylene, cyclohexylvinylether, ethylvinylether and hydroxybutylvinylether, respectively. 4.5 parts by weight of a fluorine-containing polymer having a content of 0.23 dl / g was dissolved in 15 parts by weight of xylene, and 2- (2'-hydroxy-3 ', 5'-di-butylphenyl) -5-chloro, which is a UV absorber, was added to the solution. A homogeneous application was made by adding 0.5 parts by weight of benzotriazole and 0.83 parts by weight of a polyisocyanate-based curing agent (the same product as in Example 1).

The paint prepared as described above was applied to the outer tube wall of the fluorescent lamp (FL20S.D) and then heated at 150 ° C. for 5 minutes to form a transparent film having a thickness of 30 μm.

The characteristics of the fluorescent lamp manufactured by the above method are shown in Table 1 below.

At this time, the values indicated as Comparative Example 1 in Table 1 shows the characteristics of the fluorescent lamp is not applied with the ultraviolet absorber on the outer wall surface of the glass tube, Comparative Example 2 by applying a titanium oxide film on the glass tube wall in an amount of 1.5 mg / ㎠ Shows the characteristics of the fluorescent lamp.

In addition, the spectral energy distribution curves of Examples 1 and 2 and Comparative Examples 1 and 2 are shown in FIGS. 1, 2, and 3, respectively.

TABLE 1

The coating layer prepared in the above Example was tested for UV shielding, transparency, and durability as follows.

That is, on the smoothing element plate (thickness 2.5mm) treated with glass, the coating material prepared in each example was applied so as to have a thickness of 30 占 퐉 after drying, and then dried and cured, soaked in hot water, and then the glass plate was peeled off. The cured film thus separated was used as a test piece.

On the other hand, for comparison, various synthetic resins and ultraviolet absorbents were mixed in a ratio of 90:10 by weight to form a protruding film of the mixture, but a homogeneous film was not obtained due to lack of compatibility. The film was extruded by adding 0.5 parts by weight per 100 parts by weight of the synthetic resin so as to reach the limit value of and a 50 μm thick film was prepared and used as a comparative test piece. In this case, polyethylene terephthalate (Comparative Example 3), polypropylene (Comparative Example 4), and poly-caprolactam (Comparative Example 5) were used as synthetic resins used in the comparative experiments. The same was used.

In addition, the ultraviolet shielding was measured by the ultraviolet absorption spectrum of each test piece, the transmittance at a wavelength of 370nm as an index, and the transparency and durability were promoted test ("WEL-SUN-DC" manufactured by Ducycle Weathermer-Su Tester Co., Ltd.). Type: 400 hours) before and after, the transmittance at a wavelength of 500 nm was measured and evaluated.

The results of the experiment are shown in Table 2 below.

TABLE 2

As can be seen from the above embodiment, the fluorescent lamp of the present invention is substantially the same in total luminous flux as the fluorescent lamp not coated with the ultraviolet absorber, and there is almost no difference in the light color.

Moreover, the UV transmission amount was considerably reduced compared to the fluorescent lamp coated with titanium oxide film, and especially the absorption in the UV region was significantly increased as shown in FIG. 1 and FIG. 3, and compared with that prepared from other synthetic resins as a raw material. Ultraviolet ray shielding, transparency and durability were excellent.

As described above, the fluorescent lamp according to the present name has substantially the same luminous flux as the fluorescent lamp without applying the ultraviolet absorber, and there is almost no difference in the color of the light, and has the effect of substantially blocking the ultraviolet rays. It has been found that the UV shielding properties, transparency and durability are significantly superior to lamps which form films.

Claims (6)

A fluorescent lamp comprising: a coating layer made of a solvent-soluble fluorine-containing polymer containing an ultraviolet absorber is coated on the outer wall of the glass plate. The fluorescent lamp according to claim 1, wherein the solvent-soluble fluorine-containing polymer has an intrinsic occupancy value of 0.05 to 2.0 dl / g measured in tetrahydrofuran at 30 ° C. The solvent-soluble fluorine-containing polymer according to claim 1 or 2, wherein the soluble fluorine-containing polymer has at least one curing site selected from hydroxyl groups, epoxy groups, carboxyl groups, acid amide groups, ester groups, unsaturated bonds, active hydrogens and halogens. Fluorescent lamp, characterized in that. The solvent-soluble fluorine-containing polymer according to claim 1 or 2, wherein the solvent-soluble fluorine-containing polymer is a copolymer of fluoroolefin and hydrocarbon-based vinyl ether, and the ratio of 30 to 70 mol% and 70 to 30 mol% of the fluoroolefin and the vinyl ether is respectively. A fluorescent lamp comprising a hydrocarbon-based vinyl ether or glycidyl ether in an amount of 30 mol% or less. The fluorescent lamp according to claim 1, wherein the ultraviolet absorber comprises 0.5 to 30 parts by weight per 100 parts by weight of the solvent-soluble fluorine-containing polymer. The fluorescent lamp according to claim 1, wherein the coating layer is coated with a thickness of 5 to 200 mu m.

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