JPH02206531A - Resin molding for optical parts - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] Regarding resin moldings for optical components, the purpose of this invention is to realize a fluorescent resin molding with high effective conversion efficiency of light emission and high brightness. , consisting of a plurality of fluorescent dye additives whose absorption and emission spectral characteristics differ from each other, and the wavelength band of the absorption spectrum of a specific fluorescent dye among the plurality of fluorescent dyes and the wavelength of the emission spectrum of other fluorescent dyes. The resin molded body for optical components is constructed such that the bands overlap at least in part.

[Industrial application field]

The present invention relates to a resin molded article for optical components that emits high-intensity fluorescence.

In recent years, light wave technology has been increasingly introduced into communication systems, information processing/OA equipment, and some consumer devices.

For example, optical communication using laser light, various optical disk devices, display devices using liquid crystal, etc.
This is a particularly representative example of widespread practical application.

Many optical devices or optical components are used in such optical devices, and optical glass has traditionally been the most commonly used material. Optical fibers, lenses, prisms, etc. are well-known materials. This is an example.

Optical glass has a long history and has excellent advantages such as low optical loss, the ability to change the refractive index to a considerable degree, and high processing precision.

On the other hand, with recent advances in plastic materials and plastic processing technology, optical parts made of plastic have come to be used in place of some optical parts made of optical glass. As is well known, plastic is characterized by being lightweight, extremely easy to process into various shapes, and inexpensive, and it is expected that its range of use will continue to expand in the future.

In particular, plastic materials can easily contain organic substances, such as fluorescent dyes, which cannot be used in conventional glass. There are strong expectations for the development of new fluorescent resin moldings and their application to optical components.

[Conventional technology]

BACKGROUND ART Conventionally, some fluorescent resin molded bodies, such as resin plates, are known in which a transparent resin contains a perylene-based organic dye.

These fluorescent resin molded bodies are beginning to be applied to special lighting panels and optical sensors using optical fibers, so-called fiber sensors.

FIG. 3 is an absorption/emission spectrum characteristic diagram of a conventional example of a perylene-based fluorescent dye-added transparent resin molded article, where the horizontal axis is the wavelength and the @i axis is the relative light intensity. In the figure, 3m indicates the absorption spectrum and L indicates the emission spectrum. The sample is made of polycarbonate resin as a base material, to which perylene fluorescent dye 5XlO-2% (by weight) is uniformly added, and the diameter is 1 m.
The fiber was formed into a fiber having a diameter of mφ and a length of 1 m. The spectral characteristics are measured using a halogen lamp as the light source and measuring the optical spectrum.
Using an analyzer, we followed the method normally followed for boat fishing.

In this example of perylene-based fluorescent dye-added resin, the wavelength is about 52
It has an absorption spectrum peak near 0 nm, and its half width is about 1100 nm. The peak of the emission spectrum appears at about 580 nm, which is shifted to a slightly longer wavelength side than the peak of the absorption spectrum, and orange fluorescence is emitted.

In practice, high luminance is generally required, and the luminescence energy of a fluorescent dye, that is, the luminance, is proportional to the product of absorption energy and light conversion efficiency of the fluorescent dye.

Therefore, in order to increase the absorbed energy with a constant amount of light irradiation against external light with a wide wavelength range, such as sunlight or fluorescent light, select a dye with the widest possible absorption wavelength range. It is desired to do so.

(Problems to be Solved by the Invention) However, the absorption wavelength width of a single dye is not necessarily wide enough.For example, the absorption spectrum of the above-mentioned perylene fluorescent dye has an absorption peak near 520 nm.
Its half width is also about 1100n. Therefore, blue light with a wavelength of around 400 nm is not absorbed, and the optical energy of external light with a wide wavelength range cannot be fully utilized, so there is a limit to the improvement of brightness as a fluorescent transparent resin molded product. A problem had arisen that needed to be resolved.

[Means for solving the problem] The above problem can be solved by using a transparent plastic resin base material and absorbing/
It consists of a plurality of fluorescent dye additives whose emission spectrum characteristics are different from each other, and the wavelength band of the absorption spectrum of a specific fluorescent dye among the plurality of fluorescent dyes is different from the wavelength band of the emission spectrum of other fluorescent dyes. This problem can be solved by constructing a resin molded article for optical components so that at least a portion thereof overlaps.

[Effect]

According to the present invention, as shown in FIG. 1, in a transparent plastic resin, for example, a polycarbonate resin,
In addition to the commonly used perylene fluorescent dyes,
For example, BBOT (2,5-Bis[5'-ter
t-butylbenzoxazoylthiophe
ne) to constitute a resin molded article for optical parts.

In this case, the fluorescent dye BBOT has an absorption spectrum of about 40
It is located around 0 nm and emits fluorescence at an emission wavelength of around 433 nm.

On the other hand, the wavelength band of the absorption spectrum of perylene-based fluorescent dyes widens to around 420 nm on the low wavelength side, and therefore partially overlaps with the wavelength band of the emission spectrum of BBOT.

Now, when the external incident light 4 is incident on the BBOT fluorescent dye 2 and absorbed by the circle in the center of Fig. 1, it emits 433 nm.
It emits fluorescence, which enters the surrounding three ◎, that is, perylene-based fluorescent dyes, is absorbed, and emits light. On the other hand, perylene-based fluorescent dyes directly absorb external light and emit light.

That is, a high-luminance fluorescent transparent resin molded body can be obtained by the superimposed effect of light emission due to direct absorption of light and light emission after passing through the absorption/emission process of BBOT.

〔Example〕

A polycarbonate resin with excellent heat resistance is used as a transparent plastic resin base material, and a perylene fluorescent dye and a BBOT fluorescent dye are uniformly added thereto at 2.5 x 10-2% (weight) each. A plastic fiber with a diameter of 1 mm was formed. This was cut into a length of 1 m and the spectral characteristics were measured through light.

In addition, as comparison samples, perylene fluorescent dye and BBOT
Each fluorescent dye alone, 5 Xl0-2% (by weight)
An added sample was prepared and subjected to measurement.

A halogen lamp was used as a white light source, and was connected to a fiber using an optical connector containing a lens. In addition, an optical spectrum analyzer was used as a measuring device, and it was connected to a light receiver through a lens system.

FIG. 2 is an absorption/emission spectrum diagram of a resin molded article according to an example of the present invention. ．． 1. The perylene-based fluorescent dye prepared by the method of the present invention and the BBOT fluorescent dye were each mixed at 2.5 Xl0-
2..2. is the absorption spectrum and emission spectrum when BBOT fluorescent dye is added uniformly.
．． ．． 3. The absorption spectrum and emission spectrum of the haberlene fluorescent dye alone are shown.

As shown in the figure, the emission spectrum of BBOT fluorescent dye 2. and absorption spectra of perylene-based fluorescent dyes 3. As a result, the absorption spectrum of the mixed pigmented resin is curve 1. As in, 300-450nm
There is a large increase in the wavelength band. The emission spectrum in that case showed a high peak as shown by curve 1r.

In other words, compared to the case where a conventional perylene-based fluorescent dye is added alone, a transparent resin molded article to which a BBOT fluorescent dye is mixed and added by the method of the present invention has an average luminescence energy of Approximately 1.5 times the size was obtained, making it possible to amplify the fluorescence intensity.

Although this example shows the case where two types of fluorescent dyes are added, it goes without saying that three or more types of fluorescent dyes may be added based on the spirit of the method of the present invention to further enhance the effect.

In addition, the transparent plastic resin base material may be a copolymer of polycarbonate resin or polymethyl methacrylate polystyrene.

A transparent resin such as vinyl chloride or a solid solution or copolymer thereof can be appropriately selected and used.

Further, in the embodiment, an example of a fiber shape is shown, but it goes without saying that the present invention can also be applied to irregularly shaped objects such as plates, foils, rods, and various other types of lighting panels.

〔Effect of the invention〕

As described above, according to the present invention, by adding a plurality of fluorescent dyes whose absorption/emission spectral characteristics differ from each other to a transparent plastic resin base material, a high-luminance fluorescent transparent plastic resin molded product is produced. is obtained, and through multi-stage optical conversion between multiple fluorescent dyes, it is possible to transmit the optical signal sensitive in the short wavelength range as signal light in the long wavelength range with less transmission loss through the plastic resin base material. Therefore, it greatly contributes to improving the performance of plastic resin optical parts.

[Brief explanation of the drawing]

Fig. 1 is a diagram explaining the light emitting mechanism of the resin molded article according to the embodiment of the present invention, Fig. 2 is an absorption/emission spectrum characteristic diagram of the resin molded article according to the embodiment of the present invention, and Fig. 3 is a diagram illustrating the light emitting mechanism of the resin molded article according to the embodiment of the present invention. Absorption/emission spectrum characteristic diagram of fluorescent dye-added transparent resin molding. In the figure, 1 is polycarbonate resin, 2 is BBOT fluorescent dye, 3 is
is a perylene fluorescent dye. length (n7rL)

Claims (1)

[Claims] Consisting of a transparent plastic resin base material and a plurality of fluorescent dye additives whose absorption/emission spectral characteristics differ from each other, A resin molded article for an optical component, characterized in that a wavelength band and a wavelength band of an emission spectrum of another fluorescent dye overlap at least in part.