DD301415A7 - Optical filter materials for the near IR range - Google Patents

Abstract

The invention relates to organic dyes which can be used as optical filter materials in the near IR range (NIR) between 1100 and 1600 nm. The aim of the invention is to achieve a high photo and thermal stability by means of dye-based optical filter materials and to absorb at high intensity in the UV range and in the NIR range 1 100-1 600 nm. The object of the invention is to provide dye-based optical filter materials which absorb in the NIR range between 1100 and 1600 nm and in the UV range, the entire visible spectral range being transparent. The object is achieved in that the filter material as a dye poly (N, N-dialkylamino) -tetraaryl-bis-Dithiolenneutralchelat, preferably as tetra - [(N, N-dialkylamino) -aryl] -Bis-Dithiolenneutralchelat or octa - (N, N-dialkylamino) -tetraaryl-bis-dithiolene neutral chelate of the formula I in combination with suitable organic solvents or with an optically transparent substrate or embedded in a polymer matrix, wherein Y is an arbitrarily mono- or bis-dialkylamino-substituted aromatic and at least one alkyl group on the nitrogen atom is linked via CH 2 -bridges to the aromatics, preferably in the form of a cycle, and Me is nickel, platinum or palladium. Formula I

Description

Explanation of the essence of the invention

The object of the invention is to provide dye-based optical filter materials which absorb in the NIR range between 1100 nm and 1600 nm and in the UV range, the entire visible spectral range being transparent. The object is achieved in that the filter material as a dye poly (N, N-dialkylamino) -tetraaryl-bis-Dithiolenneutralchelat, preferably as tetra - [(N, N-dialkylamino) -aryl) -Bis-dithiolene neutral chelate or octa - (N, N-dialkylamino) -tetraaryl-bis-dithiolene neutral chelate of formula I, wherein Y is an arbitrarily mono- or bisdialkylaminosubstituierter aromatic and Me means nickel, platinum or palladium.

Q <»N

st ) s

Benzene, naphthalene and thiophene are preferably suitable as dialkylamino-substituted aromatics, where at least one alkyl group on the nitrogen atom should be linked to the aromatics in forin of one cycle via CH ₂ bridges. As Y, for example, the following dialkylamino-substituted aromatics are preferably usable:

γ = -A-NR ₁ R ₂ Y = - A -

CH,

(CH

wherein A = phenyl, thionyl and naphthyl, Ri, R _{2 is} an arbitrary alkyl radical, but preferably ethyl, propyl, butyl, cyclohexyl and η = 3,4,

WXJ

R.

NR ₃ R ₄

where R ₃ , R _{4 is} an arbitrary alkyl radical, preferably ethyl, Propy I, butyl and η can vary depending on the ring between 1 and 3, and

(CH ₂ J ₃

The longest wavelength absorption maximum of the dyes used in the invention depends on the choice of the substituent and the solvent and can be optionally varied in the range 1100-1400. Due to the fact that the flanks of the absorption bands are not steep, light can also be filtered out to a wavelength of 1600 nm. Depending on the type of compound, the extinction coefficients z _mn are between 30000 and 50,000 cm ² / mmol.

The poly-IN, N-dialkylamino-tetraaryl-bis-dithiolene neutral chelates used according to the invention as optical filter materials are clearly superior to the compounds hitherto used for these purposes. They absorb much longer wavelength, they are easier and easier to handle, have a high photo and thermal stability and have due to the selected alkyl groups high solubility in both nonpolar and in polar organic solvents, so that also cuvette layer thicknesses can be used below 1 mm are.

The optical filter materials according to the invention can be used either in the form of solutions, polymer matrices in which the corresponding dye is embedded, or in the form of an optically transparent substrate to which the dye is applied.

embodiment

The invention is explained in more detail below:

The absorption parameters of two selected dyes No. 1 and No. 2 in different media are summarized in Tab.

1 shows in the form of a diagram the absorption behavior of the dyes No. 1 and No. 2 embedded in a polymethacrylate matrix in the range of 900-1 700 nm.

Dye No. 1;

Bis [bis (4,4'-diethylamino) -dithiobenzil] nickel

N (C ₂ H ₅ ),

Dye No.2: bis [dijulolidyldithio-ethanedione-1,2) nickel

The dyes can either be dissolved in organic solvents or embedded in polymer matrices which are transparent in the visible and NIFt range, the following plastic compositions preferably being suitable:

Polymethacrylate, polyvinyl chloride, cellulose acetate, cellulose propionate, cellulose acetate butyrate, polystyrene, polyvinylidene chloride, styrene or acrylonitrile polymers, polyesters.

These plastic materials are easily formed into goggle lenses or other products designed to absorb NIR radiation.

In addition, lenses, plates, etc. of the above plastic materials, glass, quartz and other optically transparent materials can be coated by known methods with the dyes described in the invention. For the separation of different wavelength ranges within the NIR between 1100-1 600 nm or for additional rejection of light in the visible spectral range, the most diverse dye combinations of the dyes described in the invention and other known dyes can be used.

Table 1

Absorption parameters of dithiolennedtralchelae 1 and 2 in solvents of different polarity

nm 10 ⁴ cmV lOOOnm 1100 nm e _x (10 ⁴ -cm ² / mmol) 0.43 0.11 1 500 nm 1 600 nm Solv. mmol 1200nm 1300nm 1400nm 1.61 0.47 Dye No. 1 1125 3.00 1.41 0.27 1195 3.12 1.02 2.81 2.07 0.54 0.07 - dioxane 0.77 2.05 1.85 2.95 1.34 0.17 - 1,2-dichloroethane 1210 2.90 3.08 hexamethylphosphoric 1215 3.10 0.59 1.53 2.05 0.50 - - säuretriamid 1 270 3.15 0.54 1.52 2.90 4.35 1.60 0.11 - nitrobenzene Dye No. 2 0.43 1.13 3.05 4.63 2.49 0.45 0.14 sulfolane 1195 4.43 2.49 4.70 2.99 1260 4.80 1.12 2.81 4.81 3.83 0.25 0.09 Essigester 1280 4.75 0.86 1.73 4.43 3.64 3.96 0.67 0.26 bromobenzene 1300 4.70 1.32 2.45 3.35 1.11 0.47 sulfolane 1325 4.96 0.70 1.57 3.84 0.97 0.31 1,2-dichloroethane 1360 4.23 0.58 1.31 2.31 1.46 0.55 nitrobenzene 0.68 1.12 2.84 2.00 0.72 dimethyl sulfoxide 2.04

Invention claims:

1. Optical filter mntorialia for the near IR range between 1100-1 600 nm, characterized in that the filter material is a dye poly (N, N-dialkylamino) -tetraaryl-bis-dithiolene neutral chalcate, preferably as tetra - [(N, N-) Dialkylamino) -aryl] -Bis-Dithiolenneutia.'chelat or Okta-iN.N-dialkylaminoJ-tetraaryl-bis-dithiolene neutral chelate of the formula I.

in conjunction with suitable organic solvents or with an optically transparent substrate or embedded in a polymer matrix, wherein Y is an arbitrarily mono- or bisdialkylaminosubstituted aromatic and at least one alkyl group on the nitrogen atom via CH ₂ bridges with the aromatic compounds, preferably in the form of a cycle and Me means nickel, platinum or palladium

 2. Optical filter materials according to item 1, characterized in that as a substituent Y optional

Y = -A-NR ₁ R ₂ and

-ON

wherein A is preferably phenyl, thienyl and naphthyl, R, and R _{2 are} any alkyl radicals, preferably ethyl, propyl, butyl and cyclohexyl and η = 3.4. 3. Optical filter materials according to item 1, characterized in that as a substituent Y optionally

is used, wherein R _{3 is} an arbitrary alkyl radical, preferably ethyl, propyl, butyl and η = 1,2 or 3

 4. Optical filter materials according to item 1, characterized in that as a substituent Y

(CH ₂ ) ₃

is used.

5. Optical filter materials according to item 1, characterized in that as substituent Y optionally the following radicals R

M ₃ R ₄

- @ yi.

HR ₃ R ₄

NR ₃ R ₄

(CH ₅ )

2'-

are used, wherein R ₃ , R _{4 are} any alkyl radicals, preferably ethyl, propyl, butyl and η = 1; 2 or 3 is.

For this 1 page drawing

Field of application of the invention

The invention relates to organic dyes which can be used as optical filter materials in the near IR region (NIR) between 1100-1600 nm. Their special absorption capacity both in the NIR and in the UV range and their permeability in the entire visible spectral range allow wide applications, eg. As the protection of the human eye, especially against laser radiation emitted in the NIR range 1100-1600nm.

Characteristic of the known; technical solutions

The interest in photo- and thermostable NIR absorption materials is growing steadily, on the one hand accounts for about 17% of the total infraiotradiation of sunlight in the range of 1000-1600nm, and on the other hand gain lasers that emit in this area, increasingly important. Although radical cation dyes, which absorb several times between 1000-1600 nm and in the visible range, are known (US-PS 3,670,025, C 07 C 87/50, DE-OS 1 693218, C 07 C 87/50, DE-OS 2012969, G 02 B 5/22, US-PS 3,5758,71, G 02 B 5/22), their stability properties are insufficient. Even glasses that are doped with rare earth metals, have several absorption bands in the visible and NIR spectral range (US Patent 4,106,857 ^ G 02 B 5/22).

Compounds which are transparent throughout the visible spectral region and have an intense absorption in the NIR represent dithiolenes and related compounds (South-Africa Pat. 67/5182; DE-OS 2802064, H 01 S 3 /.! 13; DE -OS 2058252, G 02 B 5/22).

However, the range of application of the described dithiolenes is limited to only 800-1100 nm.

Object of the invention

The aim of the invention is to achieve a high photo and thermal stability by means of dye-based optical filter materials and to absorb at high intensity in the UV range and in the NIR range 1100-1600 nm, the entire visible spectral range being transparent. In addition, the dyes should have a good solubility in organic solvents in order to guarantee an optimum filter effect at high dye concentration and cell thicknesses as possible <1 mm and allow easy embedding in very thin polymer matrices or a coating of a transparent substrate.

Explanation of the essence of the invention

The object of the invention is to provide dye-based optical filter materials which absorb in the UV range between 1100 nm and 1600 nm in the NIR range, the entire visible spectral range being transparent. The object is achieved according to the invention in that the filter material is poly (N, N-dialkylamino) -tetraaryl-bis-dithiolene-neutral chelate as dye, preferably as tetra- | (N, N-dialkylamino) -aryl-bis-dithiolene-neutral chelate or octaharalate. (N, N-dialkylamino) tetraaryl-bis-dithiolene neutral chelate of formula I, wherein Y is an arbitrarily mono- or bisdialkylaminosubstituierter aromatic and Me means nickel, platinum or palladium.

Y Y

V - '/ low

-Λ-χ ο

Benzene, naphthalene and thiophene are preferably suitable as dialkylamino-substituted aromatics, where at least one alkyl group on the nitrogen atom should be linked to the aromatics in the form of a cycle via CHj bridges. As Y, for example, the following dialkylamino-substituted aromatics are preferably usable:

Y = -A-NR ₁ R ₂

Y = - A - N

where A = phenyl, thienyl and naphthyl, R ₁ , R _{2 is} any desired alkyl radical, but preferably ethyl, propyl, butyl, cyclohexyl and η is 3,4,

(CH ₉ )

2'-

OH

NR ₃ R ₄

NR ₃ R ₄

NR ₃ R ₄

wherein R ₃ , R _{4 is} any alkyl radical, preferably ethyl, propyl, butyl and η may vary depending on the ring between 1 and 3, and

The longest wavelength absorption maximum of the dyes used in the invention depends on the choice of the substituent and the solvent and can be optionally varied in the range 1100-1400. Due to the fact that the flanks of the absorption bands are not steep, light can also be filtered out to a wavelength of 1600 nm. Depending on the type of compound, the extinction coefficients e _mtx are between 30000 and 50,000 cm ² / mmol.

The poly (N, N-dialkylaminol-tetraaryl-bis-dithiolene-neutral chelates used according to the invention as optical filter materials) are clearly superior to the compounds hitherto used for this purpose, they absorb much longer wavelengths, are easier and uncomplicated to handle, have a high photo- and Thermostability and have due to the selected alkyl groups a high solubility in both nonpolar and in polar organic solvents, so that also cuvette layer thicknesses can be used below 1 mm.

The optical filter materials according to the invention can be used either in the form of solutions, polymer matrices in which the corresponding dye is embedded, or in the form of an optically transparent substrate to which the dye is applied.

embodiment

The invention is explained in more detail below:

The absorption parameters of two selected dyes No. 1 and No. 2 in different media are summarized in Table 1.

Fig. 1 shows in the form of a diagram the absorption behavior of the dyes No. 1 and No. 2, embedded in a polymethacrylate matrix in the range of 900-1700nm.

Dye No. 1:

Bis [bis (4,4'-diethylamino) -dithiobenzil) nickel

Dye # 2: bis [dijulolidyldithio-ethanedione-1,2] nickel

The dyes can be either dissolved in organic solvents or embedded in polymer matrices that are transparent in the visible and NIR range, wherein the following plastic compositions are preferably suitable:

Polymethacrylate, polyvinyl chloride, cellulose acetate, cellulose propionate, cellulose acetate butyrate, polystyrene, polyvinylidene chloride, styrene or acrylonitrile polymers, polyesters.

These plastic materials are easily formed into goggle lenses or other products designed to absorb NIR radiation.

In addition, lenses, plates, etc. of the above plastic materials, glass, quartz and other optically transparent materials can be coated by known methods with the dyes described in the invention. For the separation of different wavelength ranges within the NIR between 1100-1 600 nm or for additional rejection of light in the visible spectral range, the most diverse dye combinations of the dyes described in the invention and other known dyes can be used.

Table 1

Absorption parameters of dithiolene neutral chelates 1 and 2 in solvents of different polarity

\ Ϊ́1 · Χ 10 "cm ² / lOOOnm 1100 nm £ j10 ⁴ -cm ² / mmol | 0.43 0.11 1 500 nm 1 600 nm Solv. nm mmol 1200nm 1300nm 1400nm 1.61 0.47 Dye No. 1 3.00 1.41 0.27 1125 3.12 1.02 2.81 2.07 0.54 0.07 - dioxane 1195 0.77 2.05 1.85 2.95 1.34 0.17 - 1,2-dichloroethane 2.90 3.08 hexamethylphosphoric 1210 3.10 0.59 1.53 2.05 0.50 - - säuretriamid 1215 3.15 0.54 1.52 2.90 4.35 1.60 0.11 - nitrobenzene 1270 0.43 1.13 3.05 4.63 2.49 0.45 0.14 sulfolane Dye No. 2 4.43 2.49 4.70 2.99 1195 4.80 1.12 2.81 4.81 3.83 0.25 0.09 Essigester 1260 4.75 0.86 1.73 4.43 3.64 3.96 0.67 0.26 bromobenzene 1280 4.70 1.32 2.45 3.35 1.11 0.47 sulfolane 1300 4.96 0.70 1.57 3.84 0.97 0.31 1,2-dichloroethane 1325 4.23 0.58 1.31 3.31 1.46 0.55 nitrobenzene 1360 0.68 1.12 2.84 2.00 0.72 dimethyl sulfoxide 2.04

Claims (2)

Invention claims: 1. Optical filter materials for the near IR range between 1100-1 600 nm, characterized in that the filter material as a dye poly (N, N-dialkylamino) tetraaryl-bis-dithiolene neutral chelate, preferably as tetra - [(N, N-dialkylamino ) -aryl] -bis-dithiolene-neutral chelate or octa- (N, N-dialkylamino) -tetraaryl-bis-diolene neutralchela.t of the formula I in conjunction with suitable organic solvents or with an optically transparent substrate or embedded in a polymer matrix, wherein Y is an arbitrarily mono- or bisdialkylaminosubstituierter aromatic and at least one alkyl group on the nitrogen atom via CH 2 bridges with the aromatics is preferably linked in the form of a cycle and Me means nickel, platinum or palladium.
2. Optical filter materials according to item 1, characterized in that as a substituent Y optional Y = -A-NR ₁ R ₂ and -ON wherein A is preferably phenyl, thienyl and naphthyl, R ₁ and R _{2 are} any alkyl radicals, preferably ethyl, propyl, butyl and cyclohexyl and η - is 3,4. 3. Optical filter materials according to item 1, characterized in that as a substituent Y optionally is used, wherein R _{3 is} an arbitrary alkyl radical, preferably ethyl, propyl, butyl and η = 1,2 or 3.
4. Optical filter materials according to item 1, characterized in that as a substituent Y is used. 5. Optical filter materials according to item 1, characterized in that as substituent Y optionally the following radicals R. NR ₃ R ₄ IiR ₃ R ₄ (CH ₀ ) 2'- HR ₃ R ₄ NR ₃ R ₄ are used, wherein R ₃ , R _{4 are} any alkyl radicals, preferably ethyl, propyl, butyl and η = 1; 2 or 3 is. For this 1 page drawing Field of application of the invention The invention relates to organic dyes which can be used as optical filter materials in the near IR region (NIR) between 1100-1600 nm. Their special absorption capacity both in the NIR and in the UV range and their permeability in the entire visible light spectral range allow broad application possibilities, eg. As the protection of the human eye, especially against laser radiation emitted in the NIR range 1100-1600nm. Characteristic of the known technical solutions The interest in photo- and thermostable NIR absorption materials is growing steadily, on the one hand account for about 17% of the total infrared radiation of sunlight in the range 1000-1600 nm, and on the other hand, lasers that emit in this area, increasingly important. Although radical cation dyes which absorb several times between 1000-1600 nm and in the visible range are known, US Pat. No. 3,670,025, C 07 C 87/50; DE-OS 1 693218, C 07 C 87/50; DE-OS 2012969, G 02 B 5/22; US-PS 3,5758,71, G 02 B 5/22), their stability properties are insufficient. Even glasses that are doped with rare earth metals, have several absorption bands in the visible and NIR spectral range (US Patent 4,106,857, G 02 B 5/22). Compounds which are transparent throughout the visible spectral region and have an intense absorption in the NIR represent dithiolenes and related compounds (South-Africa Pat. 67/5182, DE-OS 2802064, H 01 S 3/113, DE-OS 2058252, G 02 B 5/22). However, the scope of the described dithiolenes is limited to only 800-1100nm. Object of the invention The aim of the invention is to achieve a high photo and thermal stability by means of dye-based optical filter materials and to absorb at high intensity in the UV range and in the NIR range 1100-1600 nm, the entire visible spectral range being transparent. In addition, the dyes should have a good solubility in organic solvents in order to guarantee an optimum filter effect at high dye concentration and at cell thicknesses as <1 mm and allow easy embedding in very thin polymer matrices or a coating of a transparent substrate.