JPS615203A - Infrared-ray transmitting filter - Google Patents

Abstract

PURPOSE:To prevent an infrared-ray transmitting filter from being scratched or whitened by mixing polycarbonate resin with an anthraquinone dye represented by a specified general formula, melting the mixture, and molding it. CONSTITUTION:Polycarbonate resin is blended with an anthraquinone dye represented by the formula (where Z is O or imino, and R is optionally substituted alkyl), and an infrared-ray transmitting filter is formed out of the blend. The typical polycarbonate is manufactured from 2,2-bis(4-hydroxyphenyl)propane(bisphenol A). The amount of the dye blended is generally 0.01-2wt%. It is preferable that polycarbonate resin powder is mixed with dye powder, melted, extruded, and pelletized by cutting.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an infrared transmission filter. Specifically, it relates to a filter that blocks visible light and allows near-infrared rays to pass.

Various devices have been put into practical use, such as remote control devices for electrical equipment such as air conditioners and air conditioners, counting devices for articles, automatic doors, and alarm devices.

[Conventional technology]

These devices use a combination of a light emitter that generates infrared light and a receiver that receives the generated infrared light, but it is generally relatively easy to generate infrared light of a specific wavelength from a light emitter. On the other hand, many of the light-receiving elements used in light receivers have sensitivity in a wide range from near-infrared rays to visible light.

1. Therefore, in order to avoid malfunctions caused by visible light in the above-mentioned devices, it is necessary to use a filter that blocks visible light and allows only infrared rays to pass.

[Problem that the invention seeks to solve]

It is desirable that a filter for this purpose has a field near θOmμ, does not allow visible light of shorter wavelengths to pass at all, and has a pair of infrared rays of longer wavelength. The light-receiving filter is required to have a low infrared transmittance below 93;0 mμ to prevent malfunction. Furthermore, since the light-emitting and light-receiving surfaces are often used with exposed surfaces, they are required to have excellent mechanical strength and weather resistance, and to be resistant to scratches on the surface.

[Means for solving problems]

The inventors of the present invention have conducted extensive research to meet the above requirements, and have found that polycarbonate resin has excellent mechanical strength, weather resistance, heat resistance, workability, and transparency, and is resistant to scratches on the surface. We focused on the fact that it is a resin that meets the above requirements, such as not turning white even if there is a partial pressure wound.
When adding a specific compound (dye) to this, toθ
The present invention was completed based on the knowledge that it is possible to obtain remarkable light transmittance reversal characteristics in the vicinity of mμ, and to obtain excellent characteristics as a light-receiving filter.

That is, the object of the present invention is to provide an infrared transmitting filter with excellent optical and mechanical properties, and the gist of the present invention is to provide a polycarbonate resin with the general formula (in the formula, 2 and R has the same meaning as described above.) This is an infrared transmitting filter containing an anthraquinone dye represented by the following.

The present invention will be explained in detail below.

The polycarbonate resin used in the present invention is a polymer or copolymer obtained by a phosgene method in which various dihydroxydiaryl compounds are reacted with phosgene, or a transesterification method in which a dihydroxydiaryl compound is reacted with a carbonate ester such as diphenyl carbonate. Typical examples include polycarbonate resins made from co-corbis (co-hydro-S/phenyl) propane (bisphenol A).

In addition to bisphenol A, the dihydroxydiaryl compounds include bis(guhydroxyphenyl)methane, he/-bis(4t-hydroxyphenyl)ethane, co, 2-bis(Hiro-hydroxyphenyl)butane, co,
-monobis(+-hydroxyphenyl)octane, bis(
4t~hydroxy7e,=l)phenylmethane, u,,
2-bis(cuhydroxy-3-methylphenyl)furopane, /, l-bis(derhydroxy-3-tert-butylphenyl)furopane 1.2. ．． 2-bis(terhydroxy-3-bromophenyl)propane, tips. 2-bis(
Kuhydroxy-1? ~dibromophenyl)propane 1.2.2-Bis(+-hydroxy-3,!;-dichlorophenyl)propane, bis(hydroxyaryl)alkanes, /-bis(7-hydroxyphenyl)cyclopentane, / , bis(hydroxyaryl)cycloalkanes such as /-bis(lI-hydroxyphenyl)cyclohexane, +, dihydroxydiaryl ethers such as t,caged hydroxy-3,3-dimethyldiphenyl ether, +,+'-dihydroxydiphenylsulfide)'', dihydroxydiarylsulfides such as F4'-dihydroxy-3,3'-dimethyldiphenylsulfide, ti,lI'~dihydroxydiphenylsulfoxide, 'l,?'-dihydroxy- 3.3'
- Dihydroxydiarylsulfoxides such as dimethyldiphenylsulfoxide, dihydroxydiarylsulfones such as 11.4'-dihydroxydiphenylsulfone, <z4'-dihydroxy-3°3'-dimethyldiphenylsulfone, and the like.

These are used alone or in a mixture of λ or more types,
In addition to these, terephthalic acid chloride, isofucric acid chloride, piperazine, diviveridyl, hydroquinone,
Resorcinol, +, +'-dihydroxydiphenyl, etc. may be used in combination.

The dye used in the present invention is an anthraquinone dye represented by the forepaw general 2m.

In the general formula CI), 2 is an oxygen atom or an imino group, R is a substituted or unsubstituted alkyl group,
For example, carbon number/~10 such as ethyl group, propyl group, butyl group, hexyl group, octyl group, methoxypropyl group, ethoxypropyl group, ingloboxyprobyl group.
(for example, those having an alkoxy group as a substituent) or an unsubstituted alkyl group.

The above-mentioned dyes can be used alone, but they may also be used in combination with other dyes, carbon black, etc. in order to obtain better visible light blocking properties and infrared transmittance.

The blending amount of dye is 0.0 to polycarbonate resin.
The content is preferably 7 to 2% by weight, preferably about 0% by weight. If the amount is too low, visible light blocking properties will be insufficient, and if the amount is too high, the transmittance of infrared rays will be reduced.

In order to blend a dye into polycarbonate resin, it is sufficient to incorporate the dye at any stage of manufacturing a polycarbonate resin molded product, but it is possible to mix the dye powder with polycarbonate resin powder or pellets, melt-extrude it, cut it, and make pellets. A method of preparing a master pellet containing a large amount of dye and mixing it with a polycarbonate resin pellet is suitable. In order to produce molded products from these pellets, various conventionally known methods can be used. For example, it is molded into a desired shape by a method such as injection molding, extrusion molding, or compression molding.

The infrared transmitting filter of the present invention may contain other dyes, stabilizers, weathering agents, etc., as long as the optical properties thereof are not impaired.

〔Example〕

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to the following Examples unless the gist of the invention is exceeded.

2. In the examples, "parts" indicate "parts by weight."

Example/ Chip 1 of polycarbonate with an average molecular weight of 1.100θ produced from co-corbis(<z-hydroxyphenyl)propane (bisphenol A) by the phosgene method
00 parts, add formula dye o, tI parts /-! The mixture was melt-mixed using an rraρ vented extruder and a total extruder at 2gθ°C, extruded into strands, and cut into chips.

This chip was put into a 3 oz injection molding machine and the diameter and thickness were 2
Molding was carried out at 300'C using a mold for molding an m+ disc to obtain an infrared transmitting filter.

The light transmission characteristics of these filters were measured using a self-recording spectrophotometer model 118PS-3'T manufactured by Hitachi, Ltd. The results were as shown in Table 1 and Figure 1.

4 As can be seen from this result, the near-infrared transmittance of this filter is 950~
/100mμ range, t, 2% or more wavelength 7rio-
The light transmittance is reversed between g and Omμ.

Table 1 [Effects of the Invention] The infrared transmitting filter of the present invention has a large visible light blocking and infrared transmittance (, g!; Furthermore, it has excellent mechanical properties, weather resistance, processability, and other properties, so it has great industrial value.

[Brief explanation of drawings]

FIG. 1 is a graph showing the light transmission characteristics of the filter of the present invention obtained in Example 1.

Claims (1)

[Claims] (1) Polycarbonate resin has general formulas ▲mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
I] (wherein, Z represents an oxygen atom or an imino group, and R represents a substituted or unsubstituted alkyl group).