Dithiolene metal complex colorless IR absorbers

Abstract

The invention relates to the use of compounds of formulae (I) and/or (II) as colorless IR absorbers wherein M is Ni, Pd, Pt, Au, Ir, Fe, Zn, W, Cu, Mo, In, Mn, Co, Mg, V, Cr or Ti, X.sub.1, X.sub.2 and X.sub.3 are each independently of the others sulfur or oxygen, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently of the others hydrogen, NR.sub.7R.sub.8, unsubstituted or substituted C.sub.1-C.sub.18alkyl, C.sub.1-C.sub.18 alkyl wherein the alkylene chain is interrupted with oxygen, unsubstituted or substituted C.sub.1-C.sub.18alkenyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl, R.sub.7 and R.sub.8, each independently of the other, being unsubstituted or substituted C.sub.1-C.sub.18alkyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl, a further IR absorber optionally being added to the compounds of formulae (I) and (II). The invention relates also to novel dithiolene compounds of formulae (I) and (II) wherein X.sub.1 is oxygen and X.sub.2 and X.sub.3 are oxygen or sulfur. The invention relates furthermore to novel dithiolene compounds of formulae (I) and (II) wherein R.sub.1 to R.sub.6 are NR.sub.7R.sub.8. ##STR00001##

Claims

1. Compounds of formulae I and/or II ##STR00049## wherein M is Ni, Pd, Pt, Au, Ir, Fe, Zn, W, Cu, Mo, In, Mn, Co, Mg, V, Cr or Ti, X.sub.1 is oxygen, X.sub.2 and X.sub.3 are each independently of the other sulfur or oxygen, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently of the others hydrogen, NR.sub.7R.sub.8, unsubstituted or substituted C.sub.1-C.sub.18alkyl, C.sub.1-C.sub.18 alkyl wherein the alkylene chain is interrupted with oxygen, unsubstituted or substituted C.sub.1-C.sub.18alkenyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl, R.sub.7 and R.sub.8, each independently of the other, being unsubstituted or substituted C.sub.1-C.sub.18alkyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl.

2. Compounds of formulae I and/or II ##STR00050## wherein M is Ni, Pd, Pt, Au, Ir, Fe, Zn, W, Cu, Mo, In, Mn, Co, Mg, V, Cr or Ti, X.sub.1, X.sub.2 and X.sub.3 are each independently of the others sulfur or oxygen, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are NR.sub.7R.sub.8, wherein R.sub.7 and R.sub.8 are each independently of the other unsubstituted or substituted C.sub.1-C.sub.18alkyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl.

3. A compound selected from the group consisting of ##STR00051##

4. Optical filters for plasma display panels incorporating the compounds of formula I or II according to claim 1.

5. Compounds of formulae I ##STR00052## wherein M is Ni, Pd, or Pt, X.sub.1 is oxygen, X.sub.2 is sulfur or oxygen, R.sub.1, R.sub.2, R.sub.3, and R.sub.4, are each independently of the others hydrogen, NR.sub.7R.sub.8, unsubstituted C.sub.1-C.sub.18alkyl, C.sub.1-C.sub.18alkyl wherein the alkylene chain is interrupted with oxygen, unsubstituted C.sub.1-C.sub.18alkenyl, R.sub.7 and R.sub.8, each independently of the other, being unsubstituted C.sub.1-C.sub.18alkyl.

6. Compounds of formulae I ##STR00053## wherein M is Ni, Pd, or Pt, X.sub.1 and X.sub.2 are each independently of the other sulfur or oxygen, R.sub.1, R.sub.2, R.sub.3, and R.sub.4, are NR.sub.7R.sub.8, wherein R.sub.7 and R.sub.8 are each independently of the other unsubstituted C.sub.1-C.sub.18alkyl.

Description

EXAMPLES

Example 1

(1) Preparation of

(2) ##STR00022##

(3) The compound is known from J. Chem. Soc., Dalton Trans 1998, 3731-3736, and its preparation is described therein.

(4) 1,3-Diisopropyl-4,5-dioxo-imidazoline-2-thione is reacted under reflux conditions with metallic nickel and Lawesson's reagent

(5) ##STR00023##
in chlorobenzene.

(6) Absorption maximum (chloroform): 1001 nm (79 000)

Example 2

(7) Preparation of

(8) ##STR00024##

(9) Reaction is carried out analogously to Example 1, with platinum dichloride and Lawesson's reagent.

(10) Absorption maximum (chloroform): 1000 nm (113 000).

Example 3a

(11) Preparation of

(12) ##STR00025##

(13) 12.26 parts of N,N-dimethylhydrazine are added at room temperature, with stirring, to a solution of 7.65 parts of carbon disulfide in 250 parts of dichloroethane. The temperature is then increased to 40° C. and stirring is carried out for 16 hours at that temperature to complete the reaction. The temperature is subsequently increased to 80° C. for one hour.

(14) A further 750 parts of dichloroethane are then added, and 13.88 parts of oxalyl chloride (dissolved in a small amount of dichloroethane) are added dropwise over a period of 90 minutes. The reaction mixture is then heated to reflux and maintained at reflux for 2 hours, after which it is concentrated and the yellow crystals are filtered off and washed with a small amount of dichloroethane. After drying, 14 parts of product having the structure indicated above are obtained.

Example 3b

(15) Preparation of

(16) ##STR00026##

(17) 0.333 part of platinum dichloride is added to a solution of 0.541 part of the product from example 3a and 1.085 parts of Lawesson's reagent in 50 parts of toluene. The reaction mixture is maintained at 110° C. for 90 minutes and filtered while hot, and 500 parts of n-hexane are added to the filtrate after cooling. The resulting precipitate is filtered off and dried, yielding 0.5 part of product (absorption maximum 994 nm).

Example 4

(18) The procedure is analogous to that in the previous examples, except that the metal used is molybdenum, thus yielding the corresponding 1:3 molybdenum complex:

(19) ##STR00027##

Example 5

(20) Preparation of

(21) ##STR00028##

(22) The compound from Example 2 is oxidised with atmospheric oxygen in dichloromethane at reflux temperature to form the corresponding oxo compound. Its absorption maximum is found at 968 nm.

Example 6a

(23) Preparation of

(24) ##STR00029##

(25) 29.14 parts of 1,3-di-n-propyl-urea are dissolved in 300 parts of toluene at 40° C. Over a period of 40 minutes 27.18 parts of oxalyl chloride are added at 80° C. to the stirred solution. After a further hour of stirring at 100° C. the solution is evaporated at 60° C. to dryness: 36.8 parts of the product are obtained.

Example 6b

(26) Preparation of

(27) ##STR00030##

(28) 1.59 parts of the product from Example 6a, 1.06 parts of platinum dichloride and 3.47 parts of Lawesson's reagent are heated to 110° C. under nitrogen in 100 parts of toluene. After 45 minutes reaction time the dark solution is cooled down to −10° C. and the precipitation is filtered off, washed with ethanol and some acetone. For purification the crude product is dissolved in dichloromethane and precipitated slowly by addition of methanol. Dark blue crystals are collected by filtration. The absorption maximum of the product is found at 900 nm (chloroform).

Example 7

(29) Preparation of

(30) ##STR00031##

(31) Proceeding analogously to Example 6b but using palladium chloride instead of platinum chloride the corresponding palladium complex with an absorption maximum of 921 nm is obtained.

Example 8

(32) Preparation of

(33) ##STR00032##

(34) Proceeding analogously to Example 6b but using metallic nickel instead of platinum chloride the corresponding nickel complex with an absorption maximum of 891 nm is obtained.

Example 9 to 24

(35) Compounds of Examples 9 to 24 (structures given in the table below) are obtained by analogous procedures as described in Examples 1 to 8:

(36) TABLE-US-00004 Example  9 10 11 12 13 14 15 16 0 17 18 19 20 21 22 23 24

Application Examples

Example A1 (Security Printing)

(37) 11.9 parts of vinyl chloride, 2.1 parts of vinyl acetate, 10 parts of ethoxypropanol, 75.5 parts of methyl ethyl ketone and 0.5 part of the product from Example 1 are shaken together with 150 g of glass beads for 30 minutes in a Skandex mixer.

(38) The resulting printing ink is applied to contrast paper using a doctor blade (film thickness when damp: 6 μm). The print is visually colorless, but is clearly visible in the IR range using an IR-viewing device (cut-off filter 715 nm). The fastness to light is excellent.

Example A2 (Security Printing)

(39) By proceeding as indicated in Example A1 but using the IR absorber from Example 2, there accordingly is likewise obtained a colorless print having excellent fastness to light, which is clearly visible in the infrared range using an IR-viewing device.

Example A3 (Laser-Welding of Plastics Material)

(40) Using an injection-moulding machine, the IR absorber from Example 1 is incorporated into a polycarbonate disc having a thickness of 2 mm (concentration: 100 ppm). Using an Nd:YAG laser, the resulting, virtually colorless disc is welded at a power of 30 watt and a rate of advance of 20 mm/s to a second 1 mm-thick pure polycarbonate disc not containing IR absorber. The resulting weld is characterised by an excellent bond, unchanged transparency, no melt irruptions and no bubbling. Under heavy mechanical loading, breakage of the discs does not occur at the welded seam.

Example A4 (Laser-Welding of Plastics Material)

(41) By proceeding as indicated in Example A3 but using the IR absorber from Example 2, a virtually colorless polycarbonate disc is likewise obtained which has excellent welding properties. The resulting weld has unchanged transparency, the welding leaves no melt irruptions or bubbling and the strength of the weld is excellent.

Examples A5 and A6

(42) By proceeding as indicated in Examples A3 and A4 but, instead of using an Nd:YAG laser (1064 nm), using a diode laser having an emission wavelength of 980 nm, similarly good results to those described in Examples A3 and A4 are obtained.

Examples A7 and A8

(43) By proceeding as indicated in Examples A3 and A4 but, instead of using an Nd:YAG laser (1064 nm), using a diode laser having an emission wavelength of 940 nm, a comparably good weld is obtained at a laser power of 80 watt.

Example A9

(44) By proceeding as indicated in Example A3, but using polypropylene discs having a thickness of 1.5 mm, the welds obtained are likewise very good.