JP2005015789A - Ultraviolet absorbing composition and coating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an ultraviolet light absorbing composition excellent in transparency, stain-proofing properties, and ultraviolet light screening properties, without causing bleeding-out of an ultraviolet light absorber, and to prepare a fluorescent lamp covering film formed out of the composition. <P>SOLUTION: The ultraviolet light absorbing composition is obtained by adding the organic ultraviolet light absorber to an adhesive fluorine resin. A fluorine resin which has functional groups, such as carbonate, carboxylic acid halide, hydroxy, carboxy, and epoxy groups, at its terminals or on its side chains is preferably used as the adhesive fluorine resin. Further, a benzotriazole-based compound is preferably used as the ultraviolet light absorber. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a UV-absorbing composition containing an organic UV absorber and a fluorescent lamp covering film comprising this composition.

  Since fluorescent light widely used as a lighting fixture emits ultraviolet rays, the article or the like may be deteriorated or discolored when the article or the like is exposed to light from the fluorescent lamp for a long time. In order to prevent deterioration or fading of articles due to ultraviolet rays, it is necessary to block ultraviolet rays emitted from fluorescent lamps. As a method for blocking ultraviolet light, for example, a method of covering a fluorescent lamp with a film capable of blocking ultraviolet light has been proposed. Such a film is required to have high transparency and antifouling properties so as not to impair the function of the fluorescent lamp as well as the ability to block ultraviolet rays. Therefore, it is conceivable to use a fluororesin excellent in antifouling property as a coating material.

Organic ultraviolet absorbers have higher transparency than inorganic ultraviolet absorbers, and are therefore preferably used for materials that require transparency. If this organic ultraviolet absorber is added to a fluororesin, a fluorescent lamp coating material excellent in transparency and antifouling property should be produced. However, since a general fluororesin has a high melting point, it has been difficult to add an organic ultraviolet absorber having poor thermal stability. In order to solve this problem, an attempt has been made to use a fluororesin having a relatively low melting point. For example, Patent Document 1 discloses a fluorescent lamp coating material in which an organic ultraviolet absorber is added to a tetrafluoroethylene-vinylidene fluoride copolymer known as a low melting point fluororesin.
JP 7-258497 A

  However, since a general fluororesin such as the above-mentioned tetrafluoroethylene-vinylidene fluoride copolymer is poorly compatible with the UV absorber, there is a problem that the UV absorber bleeds out on the surface of the fluororesin film. It was happening. For this reason, there is a problem that not only the ultraviolet blocking property cannot be sufficiently obtained, but also the film surface becomes sticky by the raised ultraviolet absorbent, and the antifouling property of the fluororesin is not sufficiently exhibited.

  Then, this invention makes it a subject to provide the ultraviolet-absorbing composition and fluorescent lamp coating material excellent in transparency, antifouling property, and ultraviolet-blocking property.

The present invention will be described below.
The first aspect of the present invention is an ultraviolet absorbing composition characterized in that an organic ultraviolet absorber is added to an adhesive fluororesin.

  Here, the “adhesive fluororesin” refers to a fluororesin having a melting point of 150 ° C. to 250 ° C. and a 180 ° peel strength of a film prepared and evaluated by the following method of 4 N / cm or more. .

(Preparation of test film)
Rexpearl RA3150 (manufactured by Nippon Polyethylene Co., Ltd.), which is a kind of modified polyolefin resin, and fluororesin are pressed at 240 ° C. for 10 minutes at a sample pressure of 4 × 10 ^{5 to} 5 × 10 ⁵ Pa to obtain a laminated sheet. A test film is prepared by cutting into a width of 2.5 cm and a length of 25 cm.
(Evaluation of test film)
180 degree peel strength is measured at a peel rate of 5 mm / min and a temperature of 23 ° C. by a method according to JIS Z0237.

  According to the present invention, it is possible to provide an ultraviolet absorbing composition that is excellent in transparency, antifouling properties, and ultraviolet blocking properties, and in which the ultraviolet absorber does not bleed out.

  The organic ultraviolet absorber is preferably a benzotriazole compound.

  According to this, it is possible to provide an ultraviolet absorbing composition having more excellent ultraviolet absorbing ability.

  The second aspect of the present invention is a fluorescent lamp covering film comprising the above ultraviolet absorbing composition.

  According to this invention, it is possible to provide a fluorescent lamp coating film that is excellent in transparency, antifouling properties, and ultraviolet blocking properties.

  As described above, according to the present invention, an ultraviolet absorbing composition that is excellent in transparency, antifouling properties, and ultraviolet blocking properties, and that does not bleed out the ultraviolet absorber, and a fluorescent lamp coating film comprising the composition. Can be provided.

  The ultraviolet absorbing composition and fluorescent lamp coating material of the present invention are composed of an adhesive fluororesin and an organic ultraviolet absorber.

The “adhesive fluororesin” in the present invention has a melting point of 150 ° C. to 250 ° C., and Rexpearl RA3150 (manufactured by Nippon Polyethylene Co., Ltd.), which is a kind of modified polyolefin resin, and fluororesin are 4 × 10 ⁵ to A laminated sheet was prepared by pressing at 240 ° C. for 10 minutes at a sample pressure of 5 × 10 ⁵ Pa, and a sample collected by cutting to a width of 2.5 cm and a length of 25 cm was applied to a method according to JIS Z0237. It means a fluororesin having a 180 degree peel strength of 4 N / cm or more when a 180 degree peel strength is measured at a peel rate of 5 mm / min and a temperature of 23 ° C.

Further, IR spectrum of the "adhesive fluororesin" in the present invention ^has an absorption peak between 1780cm ^-1 ~1880cm -1. Preferably, IR spectrum of the "adhesive fluorocarbon ^resin", between 1790 cm -1 between ～1800Cm ^-1 and ^{1845cm -1 ~1855cm} -1, have a absorption peak due to anhydride such as maleic anhydride groups and, ^{alternatively,} have an absorption peak due to end carbonate groups between 1800cm ^-1 ~1815cm -1, ^or between 1790cm ^-1 ~1800cm ^-1, between 1845cm ^-1 ~1855cm -1 and 1800 cm ^{- Between 1 and} 1815 cm ⁻¹ , it has an absorption peak due to a mixture of anhydrides such as maleic anhydride groups and terminal carbonate groups.

More preferably, IR spectrum of the "adhesive fluorocarbon ^resin", between 1790 cm -1 ～1800Cm between ^-1 and ^{1845cm -1 ~1855cm} -1, an absorption peak due to anhydride such as maleic anhydride groups Or an absorption peak due to the terminal carbonate group between 1800 cm ^{−1 and} 1815 cm ⁻¹ .

Further, the main chain due to the CH ₂ groups of the absorption peak near 2881cm ^-1 to the height of the absorption peaks between ^{1790cm -1 ~1800cm} -1 attributed to anhydride such as maleic anhydride groups of height The ratio is 0.5 to 1.5, preferably 0.7 to 1.2, and more preferably 0.8 to 1.0.

Moreover, the ratio of the height of the absorption peak between 1800 cm ⁻¹ to 1815 cm ⁻¹ due to the terminal carbonate group to the height of the absorption peak near 2881 cm ⁻¹ due to the CH ₂ group of the main chain is 1. It is 0-2.0, Preferably it is 1.2-1.8, More preferably, it is 1.5-1.7.

  As such a fluororesin having adhesive strength, for example, a homopolymer or copolymer having a tetrafluoroethylene unit, such as a carbonate group, a carboxylic acid halide group, a hydroxyl group, a carboxyl group, or an epoxy group at the terminal or side chain A resin having a functional group of A plurality of resins may be mixed as long as the melting point and the adhesive strength are expressed. Examples of commercially available fluororesins having adhesive strength as described above include Neoflon EFEP (manufactured by Daikin Industries) and Fullon LM-ETFE AH2000 (manufactured by Asahi Glass Co., Ltd.).

  As the organic ultraviolet absorber of the present invention, known ones can be used, for example, salicylic acid ultraviolet absorber, benzophenone ultraviolet absorber, triazine ultraviolet absorber, benzotriazole ultraviolet absorber, cyanoacrylate. Based ultraviolet absorbers and the like. Of these, benzotriazole-based ultraviolet absorbers are preferred in that they have excellent absorption wavelength range and absorption ability. Examples of the benzotriazole ultraviolet absorber include Tinuvin P and Tinuvin 320 (manufactured by Ciba Specialty Chemicals).

  The addition amount of the organic ultraviolet absorber varies depending on the thickness of the film, but 0.05 to 1.0% by mass with respect to the adhesive fluororesin based on the mass of the adhesive fluororesin (100% by mass). It is preferable to add. Specifically, as a fluorescent lamp coating film, an ultraviolet absorber according to the thickness of the fluorescent lamp coating film so as to block light of 300 nm to 500 nm by 75% or more and transmit light of 500 nm or more to 80% or more. What is necessary is just to adjust the addition amount.

  The thickness of the fluorescent lamp covering film of the present invention is not particularly limited, but is preferably 10 μm to 100 μm.

  The method for forming the ultraviolet absorbing composition of the present invention is not particularly limited, and examples thereof include a calendar method and an extrusion method. The method for coating the fluorescent lamp with the fluorescent lamp coating film of the present invention is not particularly limited. For example, a method in which a pre-formed film is wound around a fluorescent lamp or a fluorescent lamp is inserted into a film that has been formed into a tube shape in advance. And a method of performing heat treatment to make close contact.

  In addition to the ultraviolet absorber described above, various additives may be added to the fluorescent lamp coating film of the present invention as necessary. Examples of the additive include calcium carbonate and talc for improving slipperiness.

  In addition to the fluorescent lamp coating film, the ultraviolet absorbing composition of the present invention can be used, for example, as a release film that can be processed such as drilling with an ultraviolet laser.

(Example 1)
To 100 parts by mass of Neofluorone EFEP EP-5000 (manufactured by Daikin Industries), which is an adhesive fluororesin, 0.5 part by mass of Tinuvin P (manufactured by Ciba Specialty Chemicals) is added and melted with a twin screw extruder, It was melt-extruded from an annular die having a temperature of 300 ° C. and cooled with water to obtain a transparent tubular film having a thickness of 50 μm and a diameter of 40 mm. Immediately after the production of the tubular film, the transmittance of ultraviolet rays of 360 nm or less was measured, and the transmittance was as good as 1% or less.
The obtained tube-shaped film was set on a 20 W fluorescent tube, and after the fluorescent lamp was turned on for one month in the laboratory, the transmittance of ultraviolet rays of 360 nm or less and the state of the film surface were examined. As a result, the transmittance was 5% or less, and a low transmittance was maintained. Further, the film surface was free of dirt and bleed-out of the UV absorber, and the transparency and antifouling properties were good.

(Comparative Example 1)
Add 100 parts by mass of tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer (THV220G, manufactured by Dinion), which is a low melting point fluororesin, to 0.5 parts by mass of Tinuvin P (manufactured by Ciba Specialty Chemicals) Then, it was melted by a twin-screw extruder, melted and extruded from an annular die having a die temperature of 300 ° C., and cooled with water to obtain a slightly turbid tubular film having a thickness of 50 μm and a diameter of 40 mm. Immediately after the production of the tubular film, the transmittance of ultraviolet rays of 360 nm or less was measured, and the transmittance was about 5%.
The obtained tube-shaped film was set on a 20 W fluorescent tube, and after the fluorescent lamp was turned on for one month in the laboratory, the transmittance of ultraviolet rays of 360 nm or less and the state of the film surface were examined. As a result, the surface of the film was whitened by bleeding out of the ultraviolet absorber, and further, dust adhered and became dirty. Further, the ultraviolet transmittance increased to about 10%, and the ultraviolet absorption effect of the film was inferior.

  As described above, the fluorescent lamp coating film made of the ultraviolet absorbing composition of the present invention is a transparent film without turbidity, and the UV absorber does not bleed out on the film surface and has excellent performance. . The inventors of the present invention can improve the transparency in the fluorescent lamp coating film of the present invention because the adhesive fluororesin can highly disperse the organic ultraviolet absorbent, It is considered that the bleeding out of the ultraviolet absorber can be suppressed by the interaction between the carbonate group and / or maleic anhydride group in the adhesive fluororesin and the organic ultraviolet absorber.

While the present invention has been described in connection with embodiments that are presently the most practical and preferred, the present invention is not limited to the embodiments disclosed herein. However, the present invention can be changed as appropriate without departing from the spirit or concept of the invention that can be read from the claims and the entire specification, and an ultraviolet absorbing composition and a fluorescent lamp coating film accompanying such changes are also disclosed in the present invention. Should be understood as being included in the scope.

Claims (3)

An ultraviolet absorbing composition comprising an adhesive fluororesin and an organic ultraviolet absorber added thereto. The ultraviolet absorbing composition according to claim 1, wherein the organic ultraviolet absorber is a benzotriazole compound. A film for covering a fluorescent lamp, comprising the ultraviolet absorbing composition according to claim 1.