JPH0643559B2 - Blue dye for filters - Google Patents

Description

TECHNICAL FIELD The present invention relates to a blue dye for optical color filters.

(Prior Art) Currently, many filters have gelatin as a base material, and thus have insufficient durability. So as a base material,
The use of a resin having good durability or an inorganic transparent substance has been studied (Japanese Patent Laid-Open No. 59-127036).

(Problems to be Solved by the Invention) As a transparent coloring material of a resin or an inorganic substance, an oil-soluble dye or a disperse dye is known (Dye Handbook, Maruzen).

However, among these dyes, no dye has sufficient coloring properties and durability (particularly light resistance and heat resistance) and has excellent spectral characteristics.

Further, there is no dye suitable for a method such as a sublimation vapor deposition method (Japanese Patent Laid-Open No. 59-127036), which is being investigated as a method for producing a new filter.

(Means for Solving Problems) As a result of intensive studies, the present inventors have found a dye having excellent light resistance and heat resistance, and completed the present invention.

That is, the invention has the general formula (I) [In the general formula (I), X and Y are nitro group, hydroxy group or amino group, R ¹ is halogen, R ² is alkyl group, alkoxy group or alkoxycarbonyl group, R ³ is alkyl group, alkoxy group or halogen. Indicates. ] It is a blue dye for filters represented by.

The dye of the present invention is represented by the above general formula (I), and in the formula, the alkyl group represented by R ^{2 to} R ³ is a linear or branched alkyl group having 1 to 20 carbon atoms. Named
For example, the alkoxy group is preferably a methoxy group, an ethoxy group, a propoxy group or a butoxy group, the alkoxycarbonyl group is preferably a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group or a butoxycarbonyl group, and the halogen is Br. , I, Cl, F
Is.

In order to produce the dye of the present invention, dinitrodihydroxyanthraquinone or tetrahydroxyanthraquinone and its leuco form are reacted with an aniline derivative and halogenated by a known method. It is obtained by reducing with.

The dye of the present invention obtained by such a method,
Examples include dyes shown in Table 1.

Table 1 shows the dyes of the present invention and their performance as filters.

In Table-1, the performance tests and evaluations are as follows.

1) Coloring property PET (polyethylene terephthalate): Coloring property when a film, dye base and ethylene glycol are put and dyed at 130 ° C for 1 hour PS (Polystyrene): Coloring property when resin and dye are mixed and molded Al : Alumina gel is applied to glass and fired, and coloring property when dye is transferred to the obtained base material (γ-alumina) 2) Heat resistance Each colored base material (PET, PS, Al) in air 180
No change in the amount of change in transmission spectrum after heating at ℃ for 4 hours ◎ 10% or less ○ Within 30% △ 30% or more × 3) Light resistance Fade meter for each colored substrate (PET, PS, Al) 20 hours There is no change in the amount of change in the spectrum after that. ◎ 10% or less ○ Within 30% △ 30% or more × 4) Sublimation property ○ When sublimation occurs at 200 ° C or less under atmospheric pressure, it is marked as ×, and when it does not sublimate, it is marked as ×.

5) Filter performance ○ If the transmittance at 460nm of the substrate colored at a concentration such that the transmittance at 540nm is 5% or less is 55% or more, ○, if it is 55% or less, ×
Indicated by.

Examples of the substrate colored with the dye of the present invention include thermoplastic resins (polystyrene, polyethylene, polypropylene,
Acrylic resin, ABS resin, polyacetal, polycarbonate, etc., thermosetting resin (amino resin, phenol resin, polyurethane, polyester, polyether sulfone, polyether ether ketone, etc.), alumina film (retained on glass or resin), silica film (Holding on glass or resin), etc., the coloring method is
Transfer, dyeing, sublimation deposition, etc. can be applied.

(Operation and effect) Conventional filters had problems in durability, colorability, etc., but when the dye of the present invention is used, a filter having excellent colorability can be obtained, and heat resistance, light resistance, sublimability, and further It is possible to obtain a colored filter having excellent spectral characteristics in practical use.

(Examples) Hereinafter, the present invention will be described in detail with reference to Examples. However,
"Parts" represent parts by weight.

Example-1 10 parts of 1,5-dihydroxy-4,8-dinitroanthraquinone,
70 parts of 2,4-dimethylaniline were mixed and heated and stirred at 150 ° C. for 3 hours. The reaction product was discharged into methanol, and the precipitated solid was filtered off and dried to obtain 12 parts of the compound of the following formula.

Subsequently, 50 parts of sulfolane and 12 parts of the dinitroanthraflavic acid derivative obtained above were mixed, 7.2 parts of bromine was gradually added dropwise at room temperature, and after completion of the addition, the mixture was heated with stirring at 50 ° C. for 2 hours.
After completion of the reaction, the solid was discharged into water and the precipitated solid was separated by filtration and dried. This was purified by column to obtain 14 parts of a compound represented by the following formula.

λmax (in chloroform) 612nm Elemental analysis After mixing 10 parts of this dye with 100 parts of polypropylene glycol and atomizing it, it is applied to paper and dried to make transfer paper. Alumina gel is applied and baked on a glass plate with a thickness of 3 mm at 200 ° C.
It was transcribed in to make a blue filter. Figure 1 shows the chart obtained by measuring the spectral characteristics (transmittance) of this filter with a spectrophotometer.

Example-2 Leuco-1,4,5,8-tetrahydroxyanthraquinone 2.
7 parts, 1,4,5,8-tetrahydroxyanthraquinone 10 parts,
50 parts of ethyl alcohol, 6.3 parts of boric acid and 7.0 parts of 2,4-dimethylaniline were mixed and reacted at 80 ° C. for 2 hours. After filtering off the reaction product, a bromination reaction was carried out in the same manner as in Example 1 and 13 parts of the following dye was obtained by column purification.

λmax (in chloroform) 635nm Elemental analysis A dyebath containing 2 parts of the dyestuff obtained and 10 parts of a polyester film and 2000 parts of ethylene glycol was treated at 130 ° C. for 1 hour to dye the polyester film to prepare a blue filter.

The chart obtained by measuring the spectral characteristic (transmittance) of this filter with a spectrophotometer is shown in FIG.

Example-3 Compound of the following formula synthesized in the same manner as in Example-1 10 parts of ethanol, 60 parts of water, 20 parts of water and 7.2 parts of sodium sulfide were mixed, and heated and stirred at 80 ° C. for 4 hours. After filtering off the reaction mixture, 6 parts of the dye of the following formula was obtained by column purification.

λmax (in chloroform) 636nm Elemental analysis 1 part of this dye, 10 parts of Pyronal MD-1200 (manufactured by Toyobo Co., Ltd.) and 1 part of silica gel are mixed, atomized, coated and dried to prepare a transfer paper (the dye is arranged for a filter), which is polymethyl. Place on a methacrylate resin plate, 200
After passing through a calendar at ℃, a blue filter was obtained.

The chart obtained by measuring the spectral characteristics (transmittance) of this filter with a spectrophotometer is shown in FIG.

[Brief description of drawings]

FIGS. 1, -2 and 3 use the dye according to the present invention,
It is a figure which shows the transmittance | permeability in the spectrophotometer in each wavelength of the filter produced in Example-1, -2, and Example-3.

Claims (1)

[Claims] 1. A compound represented by the general formula (I), [In the general formula (I), X and Y are a nitro group, a hydroxy group or an amino group, R ¹ is a halogen, R ² is an alkyl group,
An alkoxy group or an alkoxycarbonyl group, or R ³
Represents an alkyl group, an alkoxy group or halogen. ]
A blue pigment for filters represented by.