JPH06328642A - Filter for illumination - Google Patents

Abstract

PURPOSE:To provide excellent transparency, high heat resistance and flame retardance by coating to form both or one surface of a highly transparent polyethylene terephthalate film in which substance for imparting flame retardant effect is added with a coating agent layer containing transparent resin as a main body. CONSTITUTION:This illumination filter comprises a film base material layer 2 of highly transparent polyethylene terephthalate having a thickness of 50-200mum and in which substance for imparting flame retardant effect is added. Transparency is important, in addition to flame retardance, for the filter, and coating agent for constituting the filter does not disturb transparency together with the film base material. Resin soluble in solvent is selected, and a suitable colorant for forming a transparent coating agent by mixing it with transparent resin is selected from dyes. Both or one surface of the layer 2 is coated with the agent obtained by coloring the soluble transparent resin with the dye to provide coating agent layers 1, 1'. A thickness of the layers 1, 1' of each side is 5-100mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter for lighting, which is required to have high transparency and a flame retardant effect, which is used for lighting equipment which emits high temperature or various kinds of ordinary lighting.

[0002]

2. Description of the Related Art Heretofore, it has been essential for a filter of this type to have transparency and heat resistance, and to be easy to handle and inexpensive because there are many types. Furthermore, since the high heat emitted from the light source is directly received, not only heat resistance but also measures against ignition during use are important. Synthetic resin with good transparency, which allows you to obtain toning freely and accurately as specified,
It is intended for exclusive use.

Among various synthetic resins, the polyethylene terephthalate film has a characteristic that it is easy to meet this requirement, but since it has flammability, it is dangerous in terms of safety such as fire. In order to compensate for this drawback, a flame retardant is added to the molding resin at the time of molding the film, or a resin containing a flame retardant is applied to the film.

When a flame retardant is added to a film-forming resin, the decomposition temperature of an organic flame retardant such as a halogen-containing or phosphorus-based resin is generally lower than the molding temperature of a polyethylene terephthalate film (about 260 to 320 ° C.). Since it is low, it is useless, and since the inorganic flame retardant having a high decomposition temperature is opaque, a general polyethylene terephthalate film could not be used for the indicated use.

On the other hand, the method of applying a resin containing a flame retardant to a highly transparent polyethylene terephthalate film can impart flame retardancy so as not to impair the transparency of the film, but it is reinforced for applications where transparency is important. Since it was difficult to use, I knew that ignition and combustion would occur due to the high heat of the light source during use, and I used it while replacing it with a new one each time I used it for a short time.

However, in JP-A-4-123230, a general highly transparent polyethylene terephthalate film (generally referred to as T type) is used as a substrate, and an isocyanate compound is reacted on both sides or one side of this film. By applying a coating agent mainly composed of a transparent resin added in an amount equal to or more than the equivalent amount, it is possible to preliminarily use di- and poly-based materials in the raw material of the transparent resin in the coating agent without using any additive called a flame retardant. It was found that the flame retardant transparent resin can be obtained by adding an isocyanate compound in excess of the reaction equivalent to the resin of the raw material, and this resin coating method solves the problem of the illumination filter.

[0007]

The method for improving the properties of the film-forming resin itself has not seen technical development worthy of adoption until recently, but it is also seen as a trigger for breaking the bottleneck. An invention relating to a water-soluble polyester composition was published (Japanese Patent Application Laid-Open No. 5-65394), and the corresponding product was presented by the corporation that was the same applicant. The inventor
Taking this as an opportunity, I thought that it would be possible to develop a practical lighting filter by using a film in which a flame retardant was added to the molding resin.

[0008]

In order to achieve the above object, the illumination filter of the present invention is limited to a highly transparent polyethylene terephthalate film among polyester compositions having a flame retardant effect as a base material. It is adopted, and a resin liquid colored with a dye or a pigment is applied to one or both surfaces of the resin to commercialize it.

When a synthetic resin film is used as a lighting filter, it goes without saying that it can be handled easily, but in addition to that, it is required to satisfy the optimum conditions for sufficiently exhibiting the performance as a filter. To be done. The thin film improves the light transmittance, which is advantageous in terms of optical performance, but not only tends to cause an excessive load in terms of material strength, but also makes it difficult to attach the film to a spotlight. No matter how excellent the flame retardancy is, an excessively thin film is unsuitable for use.

A filter using a synthetic resin film is more flexible than a filter made of an inorganic material such as glass, so that there is almost no risk of breakage, but heat radiation is poor and heat resistance is insufficient. Therefore, if the material is made thick in order to reinforce the material strength, heat dissipation is further lowered, heat is more easily accumulated, and aging due to heat is easily promoted.

Due to the above reasons, the selection of thickness is an important factor in a filter using a synthetic resin film as a substrate. According to the results of practical use, it was found that in the highly transparent polyethylene terephthalate film having a flame retardant effect, it is desirable that the thickness is in the range of 50 to 200 μ, and the thickness of around 75 μ is most desirable.

In the illumination filter of the present invention, it is important that the transparency is as good as the flame retardancy. For that purpose, it is an essential condition that the film base material has excellent transparency, but the coating agent that constitutes the filter together with the base material should not interfere with the transparency. It is not suitable for the present invention if the colorant used in combination with the resin, which is the main component of the coating agent, causes cloudiness or cloudiness.

Therefore, it is necessary to select a resin that is not a dispersion type and is soluble in a solvent as the resin used for the coating agent. Examples of such resin include phenol resin, epoxy resin, methacrylic resin, ABS resin, amide resin, allyl resin, fluororesin, melamine resin, unsaturated polyester resin, saturated polyester resin, polystyrene resin, polyurethane resin, vinyl chloride resin, Silicone resin, urea resin, etc. can be used, but acrylic resin and saturated polyester resin are comprehensively superior in terms of heat resistance, transparency, and compatibility with dyes, and are easy to handle, so they are suitable for the present invention. I found that it can be used for.

Regarding the coloring material used in the coating agent, the dispersion type pigment-like material is insoluble in the solvent and thus impairs the transparency. In this case as well, it is possible to obtain transparency by using a dispersant, a surfactant, and a compatibilizer together, but during use, the filter is whitened due to heat aging, and a chemical reaction with the pigment occurs. It causes discoloration, or it rises on the filter surface, causing adverse effects such as bleeding and blocking. Therefore, it is necessary to select an appropriate dye from the dyes. As this dye, azo dye, anthraquinone dye, indigoid dye, sulfur dye, triphenylmethane dye, virazolone dye, stilbene dye, diphenylmethane dye, xanthene dye, alizarin dye, acridine dye, quinoneimine dye, thiazole dye, methine dye, nitro dye There are dyes, nitroso dyes, etc., and any of them can be mixed with the transparent resin to form a transparent coating agent. The range of the thickness of the coating agent layer was set in the range of 5 to 100 μ in consideration of the same conditions as in the case of determining the thickness of the film base material.

[0015]

In the lighting filter constructed as described above, a highly transparent polyethylene terephthalate film containing a substance imparting a flame retardant effect is coated with a coating agent obtained by using a predetermined synthetic resin and a dye. To provide a coating agent layer. In this way, both flame retardancy and high transparency are achieved, and the thickness of the film base material and the coating agent layer is limited to a certain range to improve the workability during use and the heat resistance durability. It is a thing.

[0016]

EXAMPLES The illumination filter of the present invention will be specifically described below, but the present invention is not limited to the examples.

FIG. 1 is a schematic sectional view showing an example of the structure of the illumination filter of the present invention, and FIG. 2 is a schematic sectional view showing another example. This lighting film is a film substrate layer 2 made of a highly transparent polyester film (manufactured by Toray Industries, Inc.) having a thickness of 75 μm and containing a substance imparting a flame retardant effect. Acretan C (Fujikura Chemical Co., Ltd. ) Made 10
1 part by weight of Resin Resin Blue K (manufactured by Mitsubishi Kasei Co., Ltd.) was applied to 0 part of the colored resin solution, and 1
The colored resin layer 1 having a thickness of 25 μ was provided by drying at 00 ° C. for 3 minutes. In FIG. 1, the colored resin layer is provided on only one side of the film substrate layer, but in some cases, as shown in FIG. 2, a colored resin layer 1 ′ may be provided on another side as well.

The lighting film samples thus obtained were tested for suitability for flame retardancy by the UL-94VTM test, and the presence or absence of change in appearance was observed by the exposure test of 1500 W upward spotlight irradiation for 1 hour. , Excellent flame retardancy (VTM-0 grade), no change due to irradiation was observed. On the other hand, a conventional highly transparent polyester film (Lumirror T-60 manufactured by Toray Industries, Inc.) as a film base of the example of the present invention
In the same test, no change due to irradiation was observed, but the flame retardancy test failed.

[0019]

Since the present invention is constructed as described above, it has the following effects.

According to the first aspect of the present invention, since a highly transparent polyethylene terephthalate film having excellent flame retardancy is coated with a coating agent layer mainly composed of a special transparent resin, the transparency is good, and the heat resistance and flame retardancy are excellent. A rich lighting filter can be obtained.

In the second aspect, since the thickness of the film base is limited and the constitution and thickness of the coating agent layer are limited, the obtained lighting filter can be easily handled, and heat storage in the material is reduced. In addition, by promoting aging resistance associated with temperature rise, long-term use is possible, and economic efficiency is improved.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of the structure of an illumination filter of the present invention.

FIG. 2 is a schematic sectional view showing another example of the structure of the illumination filter of the present invention.

[Explanation of symbols]

 1, 1'colored resin layer 2 film substrate layer

Claims (2)

[Claims] 1. A lighting filter comprising a highly transparent polyethylene terephthalate film, to which a substance imparting a flame retardant effect has been added, on both sides or one side of which a coating agent layer mainly composed of a transparent resin is formed by coating. 2. The lighting characterized in that the polyethylene terephthalate film has a thickness of 50 to 200 μm, and the coating agent layer is a layer having a coating thickness of 5 to 100 μm on each side of a soluble transparent resin colored with a dye. Filter for.