Class of green/yellow emitting phosphors based on benzoxanthene derivatives for LED lighting

Abstract

The invention provides a lighting device (1) comprising (a) a light source (10) configured to generate light source light (11), and (b) a light converter (100) configured to convert at least part of the light source light (11) into visible converter light (111), wherein the light converter (100) comprises a matrix (120) containing an organic luminescent material (140) of the benzoxanthene derivative type. The lighting device may further comprise a further luminescent material (130).

Claims

1. A lighting device comprising (a) a light source configured to generate light source light, and (b) a light converter configured to convert at least part of the light source light into visible converter light, wherein the light converter comprises a matrix containing an organic luminescent material as defined by formula (I): ##STR00003## with G.sub.1 as defined above, in which A, B, C, J, Q are independently selected from hydrogen, halogen, R.sub.1, OR.sub.2, NHR.sub.7, and NR.sub.2R.sub.7, wherein R.sub.1 is independently selected from C.sub.2-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; and wherein R.sub.2 and R.sub.7 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; in which G.sub.2-G.sub.9 are independently selected from hydrogen, halogen, R.sub.3, OR.sub.3, NHR.sub.3, and NR.sub.4R.sub.3, wherein R.sub.3 and R.sub.4 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; and wherein one or more of A, B, C, J, and Q independently comprise isopropyl or tertbutyl and wherein G.sub.8 does not include an amine group.

2. The lighting device according to claim 1, wherein two of A, B, and C are independently selected from the group consisting of isopropyl and tertutyl.

3. The lighting device according to claim 2, wherein one or both of G.sub.3 and G.sub.4 are independently selected from R.sub.3 and OR.sub.3, wherein R.sub.3Y, with Y being defined according to the following structure: ##STR00004## with D, E, I, L and M independently being selected from hydrogen, halogen, R.sub.5, OR.sub.5, NHR.sub.5, and NR.sub.6R.sub.5, wherein R.sub.5 and R.sub.6 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl.

4. A lighting device comprising (a) a light source configured to generate light source light, and (b) a light converter configured to convert at least part of the light source light into visible converter light, wherein the light converter comprises a matrix containing an organic luminescent material as defined by formula (I): ##STR00005## with G.sub.1 as defined above, in which A, B, C, J, Q are independently selected from hydrogen, halogen, R.sub.1, OR.sub.2, NHR.sub.7, and NR.sub.2R.sub.7, wherein R.sub.1 is independently selected from C.sub.2-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; and wherein R.sub.2 and R.sub.7 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; in which G.sub.2-G.sub.9 are independently selected from hydrogen, halogen, R.sub.3, OR.sub.3, NHR.sub.3, and NR.sub.4R.sub.3, wherein R.sub.3 and R.sub.4 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; and wherein one or more of A, B, C, J, and Q independently comprise isopropyl or tertbutyl, and wherein either (i) A and C are isopropyl, wherein G.sub.2, G.sub.5, G.sub.7-G.sub.9, B, J and Q are hydrogen, or wherein (ii) B and C are tertbutyl, wherein G.sub.2, G.sub.5, G.sub.7-G.sub.9, A, J and Q are hydrogen.

5. The lighting device according to claim 4, wherein one or both of G.sub.3 and G.sub.4 are independently selected from R.sub.3 and OR.sub.3, wherein R.sub.3Y, with Y being defined according to the following structure: ##STR00006## with D, E, I, L and M being hydrogen.

6. The lighting device according to claim 1, wherein one or more of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 are available, one or more of these are independently selected from the group consisting of (i) C.sub.nH.sub.2n+1Om, with n being an integer from 1 to 18 and with 0mn/2, (ii) -C.sub.nH.sub.2n+1- mFm with n being an integer from 1 to 18 and with 0m2n+1, (iii) C.sub.6-C.sub.24aryl comprising one or more ether groups, (iv) C.sub.6-C.sub.24aryl comprising one or more fluor substituents, (v) C.sub.6-C.sub.24heteroaryl comprising one or more ether groups, and (vi) C.sub.6-C.sub.24heteroaryl comprising one or more fluor substituents.

7. A lighting device comprising (a) a light source configured to generate light source light, and (b) a light converter configured to convert at least part of the light source light into visible converter light, wherein the light converter comprises a matrix containing an organic luminescent material as defined by formula (I): ##STR00007## with G.sub.1 as defined above, in which A, B, C, J, Q are independently selected from hydrogen, halogen, R.sub.1, OR.sub.2, NHR.sub.7, and NR.sub.2R.sub.7, wherein R.sub.1 is independently selected from C.sub.2-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; and wherein R.sub.2 and R.sub.7 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; in which G.sub.2-G.sub.9 are independently selected from hydrogen, halogen, R.sub.3, OR.sub.3, NHR.sub.3, and NR.sub.4R.sub.3, wherein R.sub.3 and R.sub.4 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; and wherein one or more of A, B, C, J, and Q independently comprise isopropyl or tertbutyl, and wherein the lighting device further comprises a further luminescent material configured to provide red light, wherein the further luminescent material comprises an organic luminescent material as defined by formula (II): ##STR00008## in which: G.sub.1 and G.sub.6 independently comprise a group selected from a linear alkyl, a branched alkyl, an oxygen-containing alkyl, a cycloalkyl, a naphtyl, and Y; wherein each of A, B, C, J and Q independently comprise a group selected from hydrogen, fluorine, chlorine, isopropyl, t-butyl, methoxy, an alkyl with up to 16 carbon atoms, and an oxygen containing alkyl with up to 16 carbon atoms; G.sub.2, G.sub.3, G.sub.4 and G.sub.5 independently comprise a group selected from hydrogen, fluorine, chorine, isopropyl, t-butyl, methoxy, alkyl with up to 16 carbon atoms, and oxygen-containing alkyl with up to 16 carbon atoms, and X; wherein each of D, E, I, L and M independently comprise a group selected from hydrogen, fluorine, chlorine, isopropyl, t-butyl, methoxy, alkyl with up to 16 carbon atoms, and an oxygen-containing alkyl with up to 16 carbon atoms; and in which at least two selected from G.sub.2, G.sub.3, G.sub.4, and G.sub.5 at least comprise X, wherein independently at least one of D, E, I, L and M of at least two of said at least two selected from G.sub.2, G.sub.3, G.sub.4, and G.sub.5 comprise a group selected from fluorine and chlorine, especially fluorine.

8. The lighting device according to claim 1, wherein the light source is configured to provide blue light, wherein the lighting device further comprises a further luminescent material configured to provide red light, wherein the further luminescent material comprises a luminescent material selected from the group consisting of (Ba,Sr,Ca)S:Eu, (Mg,Sr,Ca)AlSiN.sub.3:Eu, (Ba,Sr,Ca).sub.2Si.sub.5N.sub.8:Eu and a quantum dot based luminescent material.

9. The lighting device according to claim 1, wherein the matrix comprises an aromatic polyester or a copolymer thereof.

10. The lighting device according to claim 1, wherein one or more of G.sub.1, G.sub.2, G.sub.3, G.sub.4, G.sub.5, G.sub.6, G.sub.7, G.sub.8 and G.sub.9, comprise a covalent link with the matrix.

11. A light converter comprising a matrix containing an organic luminescent material as defined by formula (I): ##STR00009## with G.sub.1 as defined above, in which A, B, C, J, Q are independently selected from hydrogen, halogen, R.sub.1, OR.sub.2, NHR.sub.7, and NR.sub.2R.sub.7, wherein R.sub.1 is independently selected from C.sub.2-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; and wherein R.sub.2 and R.sub.7 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryl; in which G.sub.2-G.sub.9 are independently selected from hydrogen, halogen, R.sub.3, OR.sub.3, NHR.sub.3, and NR.sub.4R.sub.3, wherein R.sub.3 and R.sub.4 are independently selected from C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.24aryl, and C.sub.6-C.sub.24heteroaryt and wherein one or more of A, B, C, J, and Q independently comprise isopropyl or tertbutyl; and wherein one or both of G.sub.3 and G.sub.4 are independently selected from R.sub.3 and OR.sub.3, wherein R.sub.3Y, with D, E, I, L and M being hydrogen, and wherein G.sub.2, G.sub.5, G.sub.7-G.sub.9, J and Q are hydrogen.

12. The light converter according to claim 11, wherein the matrix comprises polyethylene terephthalate (PET), and wherein the matrix comprises a further luminescent material embedded in the matrix.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

(2) FIGS. 1a-1f schematically depict some embodiments of the lighting device; these drawings are not necessarily on scale;

(3) FIGS. 2a-2c show synthesis schemes and a number of organic luminescent materials made, respectively;

(4) FIG. 3 shows luminescence spectra (at RT) in ethyl acetate of those materials, also in comparison with F083 (perylene);

(5) FIG. 4a-4b depicts a number of organic luminescent materials for creating luminescence spectra, as shown in FIGS. 4c-4d; and

(6) FIG. 5 depicts examples of further organic luminescent materials.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(7) FIG. 1a schematically depicts a lighting device 1 with a light converter 100, which in this embodiment at least comprises the organic luminescent material 140 according to formula 1. The organic luminescent material 140 is in this embodiment embedded in a (polymeric) matrix, such as PET. As can be seen, a remote version is shown, with a non-zero distance d between the luminescent material (in the light converter 100) and the light source(s), indicated with reference(s) 10. The lighting device 1 comprises one or more light sources 10 which are configured to provide light source light 11, especially blue and/or UV light. The lighting device 1 may comprise a plurality of such light sources. When lighting device light, indicated with reference 2, of a white nature is desired, it may be necessary to us an RGB concept, wherein the green and/or yellow color, or at least part thereof, is provided by the green and/or yellow luminescent material 140, and the blue and red light are provided by one or more of the light source and a combination of the light source and another luminescent material, especially the further luminescent material. The further luminescent material is indicated with reference 130, and provides further luminescent material light 131.

(8) The organic luminescent material 140 according to formula I provides upon excitation by the light source light 11 and/or by emission of one or more other luminescent materials, such as e.g. the further luminescent material light 131, organic luminescent material light 141. Here, the light converter 100 is remote from the light source 10, and the organic luminescent material, which is embedded in the light converter 100, is thus also remote. The optional further luminescent material 130 can also be arranged remote, see below, but is by way of example close to the light source 10, such as in a dome and/or as layer on the LED die.

(9) Just by way of example, one light source has been depicted without the further luminescent material 130. However, in another embodiment, all light sources 10 may be configured with at least further luminescent material 130. Also, by way of example three light sources 10 have been depicted. However, more or less than three light sources may be applied.

(10) Note that the light source 10 may provide blue and/or UV light. The further luminescent material 130 may especially, upon excitation (by said light of the light source 10) provide red light. Optionally, the further luminescent material 130 may also provide green and/or yellow light.

(11) FIG. 1a, and other figures, schematically depict a device with a light chamber 170, with an enclosure 171, at least partly enclosing a cavity 172, which has a transmissive part 173. In an embodiment, the transmissive part 173 comprises the light converter 100, or may especially consist of the light converter 100. The surface of the non-transmissive part of the enclosure is indicated with reference 171. At least part of the surface 171 may comprise a reflector, such as a reflective coating.

(12) The light converter 100 provides upon excitation light converter light 111, which at least comprises organic luminescent material light 141 but may optionally comprise other luminescence light as well (see below). The lighting device light, indicated with reference 2, at least comprises light converter light 111/organic luminescent material light 141, but may optionally comprise one or more of the light source light 11, further luminescent material light 131, and light of other luminescent materials (not depicted).

(13) FIG. 1b schematically depicts an embodiment wherein the light converter 100 may comprise an upstream layer with further luminescent material 130. Optionally, this may be a light converter comprising two layers comprising the same matrix, but comprising different luminescent materials. The distance of the layer with further luminescent material 130 to the light source is indicated with dl. This distance is in this embodiment non-zero, in contrast to the embodiment schematically depicted in FIG. 1a.

(14) FIG. 1c schematically depicts an embodiment wherein the light converter 100 comprises the further luminescent material 140, e.g. in the form of quantum dots, and the organic luminescent material 130 according to formula I. Both the organic luminescent material 140 and the further luminescent material 130 are in this embodiment embedded in the (remote) light converter, i.e. embedded in the (polymeric) matrix of the light converter 100.

(15) FIG. 1d schematically depicts an embodiment wherein the transmissive part 173 comprises at least two types of segments, with volumes over 0.25 cm.sup.3, wherein the two types of segments comprise different weight ratios organic luminescent material and further luminescent material. For instance, first segments only comprise the organic luminescent material 140 as luminescent material and second segments only comprises further luminescent material 130 as luminescent material. The organic luminescent material 140 may also in this embodiment be embedded in a (polymeric) matrix, such as PET. Likewise, also the further luminescent material 130 may be embedded in a (polymeric) matrix, such as PET.

(16) FIG. 1e schematically depicts an embodiment wherein the enclosure 170 comprises a transmissive diffuser 160 (as transmissive part 173) and the light converter is applied to at least part of the non-transmissive part of the enclosure 171.

(17) FIG. 1f schematically depicts a reflective configuration. As mentioned above, the organic luminescent material 140 and optionally the further luminescent material 140 may (both) be embedded in a (polymeric) matrix.

(18) Combinations of embodiments may also be applied, like the segmented light converter of FIG. 1d in combination with or alternative to the light converter(s) shown in the other drawings, such as e.g. 1a, 1b, 1e, 1f.

(19) In FIGS. 1a-1d, the lighting device comprises a light transmissive window, which comprises or consists of the matrix. Hence, the matrix may be applied as light transmissive window. In FIGS. 1e-1f, a transmissive diffuser is used as transmissive window. The transmissive window is used as an envelope, or as part of an envelope. Here, the transmissive window envelopes at least part of the cavity 172. Note that the transmissive window is not necessarily flat. The transmissive window, comprising in embodiments the matrix, may also be curved, like in the embodiment of a TLED or in a retrofit incandescent lamp (bulb).

EXAMPLES

(20) By way of Example, a few syntheses are described below. Two synthesis schemes are depicted in FIGS. 2a and 2b, respectively; a number of organic luminescent materials made is schematically depicted in FIG. 2c. Luminescence spectra of those materials, also in comparison with F083 (prior art system), are depicted in FIG. 3.

Synthesis of 2363

1. 6-chloro-2-(2,6-diisopropylphenyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (2368)

(21) A mixture of 4-chloronaphthalic anhydride (10 g, 43.0 mmol) and 2,6-diisopropylaniline (16.2 mL, 86 mmol) in AcOH (300 mL) was refluxed overnight. The mixture was cooled and poured into water. The precipitate was collected by filtration, washed with water and dried under vacuum. Purification by column chromatography on SiO.sub.2 (dichloromethane/heptane=2:1) gave 7.5 g (44%) of pure compound 2368.

2. 4-(2-nitrophenoxy)-N-(2,6-diisopropylphenyl)-1,8-naphthalimide (2369)

(22) A mixture of 2368 (7.5 g, 19.1 mmol), 2-nitrophenol (13.5 g, 34.4 mmol) and K.sub.2CO.sub.3 (5.3 g, 38.2 mmol) in NMP (300 mL) was stirred at 90 C. under nitrogen overnight. The mixture was cooled and poured into a mixture of AcOH (150 mL) and ice-water. After 5 minutes, 2 N HCl (200 mL) was added and the mixture was extracted with toluene (4). the combined organic layers were washed with water and brine, dried (Na.sub.2SO.sub.4), filtered and concentrated. Purification by column chromatography on SiO.sub.2 (dichloromethane/heptane=1/1 to 2:1) gave 6.7 g (71%) of pure compound 2369 as a white solid.

3. 4-(2-aminophenoxy)-N-(2,6-diisopropylphenyl)-1,8-naphthalimide (2370)

(23) A solution of compound 2369 (5.7 g, 11.5 mmol) in a mixture of THF (60 mL) and MeOH (50 mL) under nitrogen atmosphere was warmed to get a clear solution. The mixture was then cooled to room temperature and 10% Pd/C (2 g) was added. The mixture was stirred 2 h at room temperature under hydrogen atmosphere (balloon) then filtered over a pad of celite and concentrated. Purification by column chromatography on SiO.sub.2 (dichloromethane) gave 4.9 g (90%) of pure compound 2370 as a yellow solid.

4. 2-(2,6-diisopropylphenyl)-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (2363)

(24) A solution of compound 2370 (5.1 g, 11.0 mmol) in AcOH (80 mL) was treated with hydrochloric acid (1.5 M, 21 mL) and sodium nitrite (3.0 g, 43.9 mmol in 20 mL water) at 0 C. After 60 minutes, a solution of CuSO.sub.4.5H.sub.2O (11.24 g, 45.0 mmol) in water (130 mL) was added. The mixture was refluxed for another 0.5 h and then allowed to cool. The precipitated yellow solid was filtered, washed with water and dried under vacuum. Purification by column chromatography on SiO.sub.2 (dichloromethane/heptane=1/1 to 2:1) gave 850 mg (17%) of pure compound 2363 as a yellow solid. M+H=448.1. .sub.max (ethyl acetate)=421 nm, =25500 and 444 nm =21300. (em) (ethyl acetate) 460 nm and 490 nm.

Synthesis of 2389

1. 5,11-dibromo-2-(2,6-diisopropylphenyl)-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (2404)

(25) Bromine (2.7 mL, 53.64 mmol) was added to a solution compound 2363 (2 g, 4.47 mmol) in CHCl.sub.3 (160 mL) under nitrogen. The mixture was stirred at 60 C. for 5 h cooled to room temperature and concentrated. The various brominates products were separated by column chromatography (SiO.sub.2, eluent:toluene dichloromethane 1/1 to 2/1). Compound 2404 (1.8 g, 66%) was obtained as a yellow solid.

2. 2-(2,6-diisopropylphenyl)-5-bromo-11-phenoxy-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (2405)

(26) A mixture of 2404 (1.4 g, 2.31 mmol), phenol (1.2 g, 12.75 mmol) and K.sub.2CO.sub.3 (2.2 g, 15.92 mmol) in NMP (60 mL) was stirred at 90 C. under nitrogen overnight. Then, the contents of the flask were poured into a cold 20% acetic acid solution in water. After 5 minutes, 2 N aqueous HCl was added and stirred for 10 minutes and the precipitated solid was filtered, washed neutral with warm water and vacuum dried at 60 C. The residue was coated on silica gel and purified by column chromatography (SiO.sub.2, eluent:dichloromethane/Heptane 1/1 to 2/1). Compound 2405 (1.1 g, 76%) was obtained as a yellow solid.

3. 2-(2,6-diisopropylphenyl)-11-phenoxy-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (2389)

(27) To a clear solution of compound 2405 (600 mg, 0.97 mmol) in THF (80 mL) and MeOH (10 mL) under nitrogen was added 10% Pd/C (100 mg) and the reaction was placed under hydrogen atmosphere with a balloon. The mixture was stirred at 30 C. overnight and then filtered over Celite. The crude solid was purified by column chromatography (SiO.sub.2, eluent: toluene/dichloromethane 3/2). Compound 2389 (540 mg, 98%) was obtained as a yellow solid. M+H=540.2. .sub.max (ethyl acetate)=428 nm, =19300 and 449 nm, =18500. (em) (ethyl acetate) 479 nm and 506 nm.

Synthesis of 2-(2,6-diisopropylphenyl)-5,11-diphenyl-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (2401)

(28) Compound 2404 (500 mg, 0.83 mmol), phenylboronic acid (810 mg, 6.64 mmol), Pd(PPh.sub.3).sub.4 (40 mg, 0.03 mmol) and Na.sub.2CO.sub.3 (265 mg, 2.50 mmol) were added to a degassed mixture of EtOH (1 mL), benzene (15 mL) and water (2 mL) under nitrogen. The mixture was reacted at 80 C. overnight. The reaction was quenched by addition of water and extracted with dichloromethane (3). the combined organic layer was washed with water, brine, dried (Na.sub.2SO.sub.4), filtered and concentrated under reduced pressure. The crude solid was purified by column chromatography (SiO.sub.2, eluent:DCM/heptane 2/1). Compound 2401 (490 mg, 98%) was obtained as a yellow solid. M+H=600.3. .sub.max (ethyl acetate)=435 nm, =17700 and 455 nm, 15600. (em) (ethyl acetate) 489 nm and 516 nm.

Synthesis of 2-(2,6-diisopropylphenyl)-11-phenoxy-5-phenyl-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (2402)

(29) Compound 2405 (400 mg, 0.65 mmol), phenylboronic acid (396 mg, 3.25 mmol), Pd(PPh.sub.3).sub.4 (40 mg, 0.03 mmol) and Na.sub.2CO.sub.3 (130 mg, 1.22 mmol) were added to a degassed mixture of EtOH (1 mL), benzene (15 mL) and water (2 mL) under nitrogen. The mixture was reacted at 80 C. overnight under nitrogen. The reaction was quenched by addition of water and extracted with dichloromethane (3). the combined organic layer was washed with water, brine, dried (Na.sub.2SO.sub.4), filtered and concentrated under reduced pressure. The crude solid was purified by column chromatography (SiO.sub.2, eluent:dichloromethane/heptane 1/1 to 3/2). Compound 2402 (390 mg, 97%) was obtained as a yellow solid. M+H=616.0. .sub.max (ethyl acetate)=436 nm, =17500 and 457 nm, =16700. (em) (ethyl acetate) 491 nm and 521 nm.

Synthesis of 2413

1. 2-(2,6-diisopropylphenyl)-6-(4-methoxy-2-nitrophenoxy)-1H-benzo[de]isoquinoline-1,3(2H)-dione (2468)

(30) A mixture of 2368 (12.0 g, 30.62 mmol), 4-methoxy-2-nitrophenol (8.9 g, 52.86 mmol) and K.sub.2CO.sub.3 (8.1 g, 58.60 mmol) in N-methylpyrolidone (150 mL) was stirred at 90 C. under nitrogen overnight. The mixture was cooled and poured into a mixture of acetic acid and ice-water. After 5 minutes, 2 N HCl was added and the precipitate was collected by filtration, washed with water and with methanol (removed excess of phenol) and dried under vacuum to give compound 2468 (14 g, 87% yield) as a solid.

2. 4-(4-Methoxy-2-aminophenoxy)-N-(2,6-diisopropylphenyl)-1,8-naphthalimide 2469

(31) To a solution of compound 2468 (14.0 g, 28.31 mmol) in a mixture of THF (130 mL) and methanol (60 mL) under nitrogen atmosphere was added 10% Pd/C (3 g). The mixture was stirred overnight at room temperature under hydrogen atmosphere (balloon) then filtered over a pad of celite and concentrated. To give compound 2469 (14 g, quantitative yield) as a yellow solid.

3. 2-(2,6-diisopropylphenyl)-9-methoxy-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione 7 (2412)

(32) A nitrosylsulfuric acid solution (40 wt. % nitric acid in sulphuric acid, 5.8 mL, 33.96 mmol) was added dropwise to a solution of compound 2469 (14.0 g, 28.3 mmol) in a mixture of acetic acid (100 mL) and propionic acid (30 mL) at 0-5 C. After 1 h, the diazonium liquor was added portionwise to a boiling solution of hydrated copper (II) sulphate (28.3 g, 113.2 mmol) in water (250 mL) and acetic acid (16 mL). After the addition was complete, the liquor was boiled for 1 h, cooled, diluted with water and the precipitated yellow solid was filtered, washed with water and dried under vacuum. Purification by column chromatography on SiO.sub.2 (dichloromethane/heptane=1/1 to 2:1) gave compound 2412 (1.3 g, 9.6%) as a yellow solid.

4. 2-(2,6-diisopropylphenyl)-9-hydroxy-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione 2470

(33) A solution of BBr.sub.3 (1M in dichloromethane, 2.6 mL, 2.60 mmol) was added to a solution of compound 2412 (350 mg, 0.72 mmol) in dichloromethane (35 mL) at 0 C. under nitrogen. The mixture was stirred at 40 C. overnight, cooled to 0 C. and a solution of NaHCO.sub.3 was added. The mixture was extracted with dichloromethane (1) and then with ethyl acetate (3) and the combined organic layers were washed with water and brine, dried (Na.sub.2SO.sub.4), filtered and concentrated. Purification by column chromatography on SiO.sub.2 (dichloromethane/methanol=60/1 to 40/1) gave pure compound 2470 (284 mg, 84% yield) as a yellow solid.

5. 2-(2,6-diisopropylphenyl)-9-phenoxy-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione 2413

(34) Potassium t-butoxide (91 mg, 0.81 mmol) was added to a solution of compound 2470 (342 mg, 0.74 mmol) in THF (50 mL) at 0 C. under nitrogen and the reaction was stirred at this temperature for 15 minutes. diphenyliodonium trifluoromethanesulfonate (473 mg, 1.10 mmol) was added in one portion and the cold bath was removed. The mixture was stirred at 40 C. for 1 h then cooled to 0 C., diluted with dichloromethane and water was added. The organic phase was separated and the water phase was extracted with ethyl acetate (2). The combined organic phases were washed with brine, dried (Na.sub.2SO.sub.4), filtered and concentrated. Purification by column chromatography on SiO.sub.2 (dichloromethane/heptane=2/1 to 4/1) gave pure compound 2413 (295 mg, 73% yield) as a yellow solid. M+H=540.2. .sub.max (ethyl acetate)=429 nm, =24800 and 452 nm, =22100. (em) (ethyl acetate) 473 nm and 501 nm.

Synthesis of 2-(2,6-diisopropylphenyl)-5,11-diphenoxy-1H-xantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (2436)

(35) A mixture of 2404 (2.0 g, 3.3 mmol), phenol (10.0 g, 16.5 mmol) and Cs.sub.2CO.sub.3 (6.4 g, 19.8 mmol) in degased 1,4-dioxane (1560 mL) was stirred at 90 C. under nitrogen for 1 h. Then, a mixture of Cu(I)I (314 mg, 1.65 mmol) and N,N-dimethylglycine (510 mg, 495 mmol) in 1,4-dioxane (4 mL) was added and the reaction mixture was stirred at 90 C. under nitrogen overnight. The mixture was cooled to room temperature and the solvent removed under reduced pressure. The residue was dissolved in dichloromethane and SiO2 was added. The dichloromethane was removed under reduced pressure and the product coated on silica was poured on top of a column chromatography for purification (SiO2, eluent: dichloromethane/heptane 1/1). The compound was washed with hot heptane in a glass filter an dried under vacuum. Compound 2436 (1.0 g, 48%) was obtained as a yellow solid. M+H=632.2. .sub.max (ethyl acetate) 437 nm, =19300 and 450 nm, =19000. (em) (ethyl acetate) 499 nm.

(36) We tested the lifetime of various molecule in a PET (polyethylene terephthalate) film by measuring the lifetime under illumination with blue light at 0.5-7 W/cm.sup.2 at 60 C. The concentration and the thickness of the layers were set so that the transmission of blue light was 90%. All dyes in the PET film showed a PLQE (photoluminescent quantum efficiency) between 0.92 and 0.96.

(37) The lifetime is determined as 10% reduction extrapolated to the conditions for a TLED (0.016 W/cm.sup.2 blue and a temperature of 60 C. in air) assuming a linear dependence on the flux density. In the case of F083 a lifetime of about 100 hours was estimated while new compound 2363 showed a lifetime of about 2500 hours. This means an increase in lifetime of about 25 times. For new compound 2389 the lifetime is further increased with another factor of about 5 to 12500 hours under the same conditions. For new compound 2401 the lifetime is even further increased with another factor of about 10 to 27000 hours under the same conditions

(38) Lifetime of organic yellow emitting molecules in a PET matrix (in hours at which 10% has bleached at an exposure of 0.016 W/cm.sup.2 blue and a temperature of 60 C. in air)

(39) TABLE-US-00001 Solvent yellow F083 F170 98 2363 2389 2401 2402 2413 2436 50- 150- 400- 2500- 10000- 27000 14000 6000 12000 200 400 650 2800 15000

Examples of White Blends

Example 1

(40) Emission of various organic molecules excited by blue LED can be combined to produce white light. Herein, the emission from the molecules depicted in FIGS. 4a (material 2389, see FIGS. 2b) and 4b (N,N-Bis(2,6-diisopropylphenyl)-1,7-di(2,6-diisopropylphenoxy)perylene-3,4:9,10-tetracarboxdiimide; Cas nr. 919488-78-1), were combined with blue light to obtain white light with a spectrum shown in FIG. 4c. Such a white light can be produced showing the following values shown in the table below.

Example 2

(41) In this example the emission from the molecules depicted in FIGS. 4a and 4b were combined with blue light and also with emission from a inorganic phosphor thiogalate (SrGa.sub.2S.sub.4:Eu.sup.2+) to obtain white light with a spectrum shown in FIG. 4d, and with values as shown in the table below.

(42) TABLE-US-00002 Conversion efficiency (Lm/W optical blue) CCT CRI R9 Example 1 243 4015 81 63 Example 2 265 4016 86 22

(43) Further examples of organic luminescent materials according to formula I are depicted in FIG. 5. Herein, X may relate to a CC bond or to an oxygen, i.e. an ether bond. By way of Example, one or more of G.sub.2 and G.sub.3 comprise groups which include ether groups or which groups are fluorinated with one or more fluor substituents, or G.sub.2 and/or G.sub.3 comprise Y groups, with one or more of D, E, I, L and M comprising alkyl groups which include ether groups or which groups are fluorinated with one or more fluor substituents. The organic molecules depicted in FIG. 5 are amongst others provided as examples. Other examples, with other groups or groups located elsewhere may also be possible.