THERMAL TRANSFER IMAGING WITH INFRARED LASER AND AZAMETHINE DYES

Abstract: Donor elements for laser-induced thermal imaging processes comprising a support bearing thereon a colorant layer comprising a colorant and a selected infrared absorbing azamethine compound are disclosed.

Description: TITLE THERMAL TRANSFER IMAGING WITH INFRA-RED LASER AND AZAMETHINE DYES Field of the Invention This invention relates to thermal imaging. More particularly this invention relates to donor elements for laser-induced thermal imaging processes in which the donor element contains certain infra-red absorbing azamethine compounds. Background of t-.h-a Tnve t-ion Thermal imaging processes are well-known. In these processes a donor element comprising a colorant is heated, by, for example, a thermal head or an infra-red laser, causing the colorant to be transferred to a receptor sheet. Depending on the process, the colorant may be a dye or pigment or a mixture of dyes and/or pigments. Imagewise heating of the donor element reproduces the corresponding image on the receptor sheet. Transfer in register to the same receptor sheet from several differently colored donor elements produces a multicolored image. Different single colored donor elements or a multicolor donor element carrying different colors in different regions which can be brought into position in turn can be used for transfer. When an infra-red laser is used for thermal transfer, only a single, small, selected area is heated at one time. Since only a small region of colorant is heated and transferred, the image can be built up pixel by pixel. Computer control of such processes allows multicolor images of high definition to be produced at high speed. This process is disclosed in Baldock, UK Patent 2,083,726. In the laser-induced thermal dye transfer process, the donor element comprises a heat transferable dye, sometimes called a thermal transfer dye, usually in a formulation with a binder, supported on a substrate. The dye donor element is contacted with a receptor sheet, and the surface of the substrate irradiated with an infra-red laser to transfer the dye to the receptor sheet. For the heat transferable dye to be directly heated by the laser, a dye which strongly absorbs the wavelength of the exciting laser is required. This need to match the infra-red absorption of the dye to the emission of the laser greatly restricts the number of dyes which can be used in the laser-induced thermal transfer process. As an alternative, the dye may be heated indirectly by incorporating a separate radiation absorber, such as carbon black., into the dye layer. However, carbon black has a tendency to aggregate or agglomerate when coated so that the absorber is not uniformly distributed in the donor element. In addition, small carbon black particles tend to be carried over with the dye, contaminating the image. Alternatively, an infra-red absorbing compound can be added to the dye layer. Dye donor layers containing infra-red absorbing materials have been disclosed by, for example, Barlow, U.S. Patent 4,778,128; DeBoer, EPO Application 0 321 923 and U.S. Patent 4,942,141; and Kellogg, U.S. Patent 5,019,549. However, there is a continuing need for infra-red absorbing materials which may be used to advantage in laser-induced thermal transfer processes. Summary of the Invention This invention is a donor element for a laser- induced thermal transfer process, said donor element comprising a support bearing thereon a colorant layer, said colorant layer comprising a colorant and an infra¬ red absorbing material, said infra-red absorbing material having the following structure: (Formula I) wherein: Ri, R2, R 3 , and R 4 are each independently hydrogen; substituted or unsubstituted alkyl, acyl, alkyoxyl, aryloxyl, acyloxyl, acylamido, alkylamino, arylamino, or sulfonyl containing 1 to 8 carbon atoms; halogen; cyano; or substituted or unsubstituted phenyl; or (Ri and R 2 ) , (R 2 and R 3 ) , or (R 3 and R 4 ) are joined to form a five-, six-, or seven-membered substituted or unsubstituted aliphatic, aromatic, or heteroaromatic ring; R 5 , Rg, R 7 , and R 8 are each independently hydrogen; substituted or unsubstituted alkyl, acyl, alkyoxyl, aryloxyl, acyloxyl, acylamido, alkylamino, arylamino, or sulfonyl containing 1 to 8 carbon atoms; halogen; cyano; or substituted .or unsubstituted phenyl; or (R 5 and R7) or (R3 and R 4 ) are joined to form a five-, six-, or seven- membered substituted or unsubstituted aliphatic, aromatic, or heteroaromatic ring; Rg and Ri are each independently alkyl of 1 to 6 carbon atoms; or (R 7 and Rg) or (Rs and Ri) are joined to form a five-, six-, or seven-membered substituted or unsubstituted ring; or (Rg and Ri) are joined to form a five-, six-, or seven- membered ring; and X is C=C(CN)2, CO, or SO 2 . De ailed Desπrip ion of the Invention The invention is a donor element for thermal transfer processes particularly adapted for use in laser-induced thermal transfer imaging. The donor element comprises a colorant layer and a support. Colorant Layer The colorant layer comprises a heat-transferable colorant, an infra-red absorbing material, and, preferably, a binder. The infra-red absorbing material must have a strong absorption in the emission region of the exciting laser and should have good thermal stability so that it is not decomposed by the incident radiation. The material is preferably substantially non-transferable so it is not transferred during imaging. It is preferred that it be essentially non-absorbing in the visible so that small amounts, if transferred, will not affect the image. It is also preferred that the material be soluble in a solvent which can be used to coat the colorant layer onto the support. Infra-red absorbing materials of Formula I (supra) as defined are used in the colorant layer. Ri * * 2r ~ -3r and R 4 are each independently chosen from a number of groups, provided the presence of the group or groups does not adversely affect the properties of the infra-red absorbing material required for the operation of the invention. These properties include, for example, chemical stability, thermal stability, solubility, and absorption spectrum. ~ -lr ~ -2r ~ - 3 r and R 4 may be: hydrogen; hydroxyl; substituted or unsubstituted alkyl of 1 to 8 carbon atoms, such as, for example, methyl, ethyl, cyclopentyl, 4-methylpentyl, benzyl, and trifluoromethyl; substituted or unsubstituted phenyl, such as, for example, phenyl, m- chlorophenyl, and μ-trifluormethylphenyl; halogen, such as, for example, chlorine, bromine, and fluorine; cyano; substituted or unsubstituted alkoxy of 1 to 8 carbon atoms, such as, for example, methoxy, ethoxy, 2-ethoxyethoxy, and benzyloxy; substituted or unsubstituted aryloxy, such as, for example, phenoxy, 51-chlorophenoxy, 3-pyridyloxy, 1-naphthyloxy, and 3-thenyloxy; substituted or unsubstituted acyloxy of 1 to 8 carbon atoms, such as, for example, acetoxy, benzyloxy, and phenylacetoxy; substituted or unsubstituted aryloxycarbonyl of 1 to 8 carbon atoms, such as, for example, phenoxycarbonyl; substituted or unsubstituted alkoxycarbonyl of 1 to 8 carbon atoms, such as, for example, methoxycarbonyl; substituted or unsubstituted sulfonyl of 1 to 8 carbon atoms such as, for example, methanesulforiyl and p_-toluenesulfonyl; substituted or unsubstituted acyl of 1 to 8 carbon atoms, such as, for example, benzoyl, ji- methoxybenzoyl, and acetyl; substituted or unsubstituted acylamido of 1 to 8 carbon atoms, such as, for example, benzenesulfonamido, benzamido, and acetamido; substituted or unsubstituted alkylamino of 1 to 8 carbon atoms, such as, for example, diethylamino, ethylbenzylamino, and -i-butylamino; or substituted or unsubstituted arylamino of 1 to 8 carbon atoms, such as, for example, anilino. Alternatively, (Ri and R 2 ), (R 2 and R 3 ) , or (R 3 and R4) are joined to form a five-, six-, or seven-membered substituted or unsubstituted ring such as, for example, benzene, naphthalene, thiazole, benzothiazole, oxazole, benzoxazole, selenazole, benzoselenazole, thiazoline, oxazoline, quinoline, isoquinoline, pyridine, imidazole, benzimidazole, and indazoline. R 5 , Rβ, R 7 , and Re are independently any of the substituents given above for Ri, R 2 , R3, and R4. Alternatively, (R 5 and R 7 ) and/or (Rβ and Re) are joined to form a five-, six-, or seven-membered substituted or unsubstituted heterocyclic ring. Rg and Ri are each independently alkyl of 1 to 8 carbon atoms. Alternatively, (R 7 and Rg) and/or (Re and Ri) may be joined to form a five-, six-, or seven- membered substituted or unsubstituted ring or (Rg and Ri) may be joined to form a five-, six-, or seven- membered substituted or unsubstituted ring. X is C=C(CN) 2 , CO, or SO2. Where substitution is possible, any of the groups may be substituted by any of the well-known organic substituents, such as, for example: alkyl; alkoxy; halogen; cyano; sulfonyl; amino; alkyl amino; dialkylamino; etc., provided the presence of the substituent does not adversely affect the properties of the infra-red absorbing material required for the operation of the invention. The alkyl groups comprising any of these substituents preferably contain 1 to 8 carbon atoms. Compounds in which an alkyl group at Rg or Ri is substituted with an additional molecule of infra-red absorbing compound have been described by Higasa, Japanese Patent Application 63/165,378 (1988) . Such compounds are considered to be equivalent to the infra¬ red absorbing compounds of this invention. In a preferred embodiment, X is C=C(CN) 2 . These compounds typically absorb in the region of 750 to 870 nm and thus are well suited for use with diode lasers. In a more preferred embodiment, Ri, R2, R3' and R4 are independently hydrogen, chloro, methyl, ethyl, methoxy, ethoxy, on cyano. In a more preferred embodiment, Ri, R 2 , R 3 , and R 4 each are hydrogen. In a preferred embodiment, R 5 and R 6 are each independently hydrogen, alkyl, alkoxyl, chloro, or acylamido. In a more preferred embodiment, R5 and Rζ are each independently hydrogen or acylamido. A preferred acylamido group is acetamido (CH 3 CONH-) . In a preferred embodiment, R 7 and Rβ are each hydrogen and Rg and Ri are each independently alkyl of 1 to 6 carbon atoms. Alternatively, (R 7 and Rg) or (Rβ and R l ) are joined to form a six-me bered substituted or unsubstituted ring. Representative preferred infra-red absorbing compounds are represented by structures AM-1 to AM-14. H; R 6 - H; Rg = Ri = CH 3 R6 = Rg = Ri = CH 3 H; R 6 = H; Rg = Ri = CH 2 CH 3 H; Rζ = H; Rg = Ri = n-C 4 Hg H; Re =-* H; Rg = Ri = CH 2 CH 2 OH H; R 6 = H; Rg = CH2CH 3 ; Ri = CH 2 CH 2 CN H; R 6 = NHCOCH3; Rg = Ri = CH 2 CH 3 H; R 6 * NHCOCH3; Rg = Ri = CH 2 CH 2 CH 3 AM-9: R5 = H; R 6 = NHCOC6H5; Rg = Ri = CH3 AM-10: R5 = CH3; Rξ = NHCOCH2CH3; Rg = Ri = CH3 AM-11: R 5 = OCH2CH3; R 6 = NHCOCH2CH3; Rg = Ri = CH3 AM-12 AM-13 AM-14 The infra-red absorbing materials may be prepared by conventional synthetic methods. The synthesis of compounds AM-7, AM-8, and AM-13 from the condensation of nitrosobanzenes with dicyanovinyl analogs of indan-1,3- dione is given in K. A. Bello, J. Chem. Soo. Perkin Trans. II , 815-818, 1987. Syntheses of infra-red absorbing materials are also given in Higasa, Japanese Patent Application 63/165378 (1988) . The infra-red absorbing materials may be present in the donor layer in any concentration which is effective for the intended purpose. " In general, concentrations of 0.1% to 10% of the coating weight have been found to be effective. A preferred concentration is 1% to 5% of the total coating weight. The colorant layer comprises a heat-transferable colorant or a mixture of heat-transferable colorants. A heat-transferable colorant is a colorant, such as, for example, a dye or a pigment, which is transferred from the donor element to the receptor sheet by the action of heat. On transfer it produces the desired color on the receptor sheet. Important criteria for the selection of a heat-transferable colorant are its thermal properties, brightness of shade, light and heat fastness, and facility of application to the support. For suitable performance, the colorant should transfer evenly, in a predetermined relationship to the heat applied, so that the intensity of color on the receptor sheet is smoothly related to the heat applied and good density gradation is attained. The colorant must be migrate from the donor element to the receiver sheet at the imaging energies employed, generally 0.2 to 2 J/cm 2 . Useful heat-transferable colorants include: (a) pigments dispersed in polymeric matrices which will soften or melt on heating, and (b) dyes, such as, for example, sublimable dyes. Useful sublimable dyes, available rom Crompton and Knowles (Reading, PA) , include: Intratherm® Dark Brown (azo type. Disperse Brown 27), Intratherm® Pink 1335NT (anthraquinone type); Intratherm® Brilliant Red P-1314NT (anthraquinone type, Disperse Red 60) ; Intratherm® Red P-1339 (anthraquinone type. Disperse Violet 17); Intratherm® Blue P-1305NT (anthraquinone type. Disperse Blue 359) ; and Intratherm® Yellow 343NT (quinoline type. Disperse Yellow 54) . Representative sublimable dyes are disclosed in: Gregory, U.S. Patent 4,764,178; Hotta, U.S. Patent 4,541,830; Moore, U.S. Patent 4,698,651; Evans, U.S. Patent 4,695,287; Weaver, U.S. Patent 4,701,439; DeBoer, U.S. Patent 4,772,582; and DeBoer, U.S. Patent 4,942,141. The heat-transferable colorant and infra-red absorbing material are preferably dispersed in a polymeric binder. Typical binders include, but are not limited to: cellulose derivatives, such as, cellulose acetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate, cellulose acetate hydrogen phthalate; polyacetals, such as polyvinyl butyral; waxes having a softening or melting point of about 60°C to about 150°C; acrylate and methacrylate polymers and copolymers; polycarbonate; copolymers of styrene and acrylonitrile; polysulfones; and poly(phenylene oxide) . The binder may be used at a coating weight of about 0.1 to about 5 g/m 2 . It will be recognized that the infra-red absorbing material and the heat-transferable colorant may be present in separate layers on the support. Such an arrangements is considered to be equivalent to that described herein. Support Any material which is dimensionally stable, capable of transmitting the radiation from the infra-red laser to the colorant layer, and not adversely affected by this radiation can be used as the support. Such materials include, but are not limited to: polyesters, such as, for example, polyethylene terephthalate; polyamides; polycarbonates; glassine paper; cellulose esters; fluoropolymers; polyethers; polyacetals; polyolefins; etc. A preferred support material is polyethylene terephthalate film. The support typically has a thickness of from about 2 to about 250 microns and may comprise a subbing layer, if desired. A preferred thickness is about 10 microns to about 50 microns. Although the colorant layer can be applied to the support as a dispersion in a suitable solvent, application from solution is preferred. Any suitable solvent may be used to coat the colorant layer. The colorant layer may be coated onto the support using conventional coating techniques or it may be printed thereon by a printing technique, such as, for example, gravure printing. Receptor Sheet The receptor sheet typically comprises a support and an image-receiving layer. The support is comprised of a dimensionally stable sheet material. It may be a transparent film, such as, for example, polyethylene terephthalate, polyether sulfone, a polyimide, a poly(vinyl alcohol-co-acetal) , or a cellulose ester, such as for example, cellulose acetate. The support may also be opaque, such as, for example, polyethylene terephthalate filled with a white pigment such as titanium dioxide, ivory paper, or synthetic paper, such as Tyvek® spunbonded polyolefin. The image receiving layer may comprise a coating of, for example, a polycarbonate, a polyurethane, a polyester, polyvinyl chloride, styrene/acrylonitrile copolymer, poly(caprolactone) , and mixtures thereof. The image receiving layer may be present in any amount which is effective for the intended purpose. In general, good results have been obtained at coating weights of 1 to 5 g/m 2 . Colorant Transfer The donor elements are used to form a colored image by thermal colorant transfer. This process comprises imagewise exposure of the donor element with an infra¬ red laser so that colorant is transferred to the receptor sheet to form a colored image. The donor element may be used in sheet form or in the form of a continuous roll or ribbon. The donor element may comprise a single color or it may comprise alternating areas of different colors, such as, for example, cyan, magenta, yellow, and black. Although various types of lasers may be used to effect transfer of the heat-transferable colorant from the donor element to the receiver sheet, diode lasers emitting in the region of 750 to 870 nm offer substantial advantage in terms of their small size, low cost, stability, reliability, ruggedness, and ease of modulation. Diode lasers emitting in the range of 800 to 830 nm are preferred. Such lasers are commercially available from, for example. Spectra Diode Laboratories (San Jose, CA) . A transfer assemblage comprises a donor element and a receiver sheet in which the colorant layer of the donor element is contiguous to the image receiving layer of the receiver sheet. This assemblage may be preassembled as an integral unit when a single colored image is desired. This may be done by reversibly adhering the donor element and the receiver sheet together at their margins. After imagewise exposure, the they are separated to reveal the image on the receiver sheet. When a multicolor image is to be produced, the assemblage is formed a plurality of times. After the first colored image is transferred, the assemblage is separated and a second donor element (or another area of the same donor element which comprises a differently colored heat-transferable colorant) is brought in contact with the receiver sheet and imagewise exposed in register with the first image. The process is repeated with donor elements containing differently colored heat- transferable colorants as many times as desired. A preferred process consists of transferring cyan, yellow, and magenta images to produce a three colored image. Industrial Applicability The donor element is adapted for the production of both single color and multicolor images by a laser- induced thermal transfer process. It can be used to obtain prints of images which have been recorded electronically by various electronic devices, such as color video cameras. It can also be used to generate hard copy output in various proofing applications. The advantageous properties of this invention can be observed by reference to the following examples which illustrate, but do not limit, the invention. EXAMPLES GLOSSARY AM-7 N-(2-((1,3-bis(Dicyanomethylene)-1,3- dihydro-2H-inden-2-ylidene)amino)-5- (diethylamino)phenyl)acetamide; CAS 109347-70-8 AM-8 N- (2- ( (1, 3-bis (Dicyanomethylene) -1 , 3- dihydro-2H-inden-2-ylidene) amino) -5- (dipropylamino) phenyl) acetamide; CAS 109347-71-9 AM-13 N-[6-[[1,3-bis(Dicyanomethylene)-1,3- dihydro-2H-inden-2-ylidene]amino-l- ethyl-l,2,3,4-tetrahydro-2,2,4- trimethyl-7-quinolinyl]propanamide CAB Cellulose acetate butyrate (17% butyl); Aldrich, Milwaukee, WI Lexan® 1500 Polycarbonate; General Electric Co., Pittsfield, MA Red P-1339 Intratherm® Red P-1339; C.I. Disperse Violet 17; l-amino-2-bromo-4- hydroxyanthraquinone; CAS 12217-92-4; Crompton & Knowles Corp., Reading, PA In the examples which follow, "coating solution" refers .to the mixture of solvent and additives which is coated on the support, even though some of the additives may be in suspension rather than in solution. Amounts are expressed in parts by weight. Example I A coating solution containing the following ingredients, expressed in parts by weight, was made up: Red P-1339, 0.20; Lexan® 1500, 0.20; AM7, 0.016; and dichloromethane, 9.58. The composition was stirred to completely dissolve the solids and coated on an about 100 micron thick polyethylene terephthalate film with a doctor knife at about 50 micron wet gap and air dried to form the donor element. The coated side of the donor element was contacted with a receptor sheet of Tektronix thermal transfer paper (Tektronix Co., Wilsonville, OR) by tightly taping them together on a test drum to form a thermal transfer assemblage. The uncoated side of the donor element was exposed on a rotating drum with a 100 W infra-red laser emitting at 830 nm (Spectra Diode Laboratories, Inc., San Jose, CA) . At 0.38 J/cm 2 , bright magenta lines about 8 micron wide were obtained on the receptor sheet. A control with no infra-red absorbing material showed no image. Example 2 A coating solution containing the following ingredients, was made up: Red P-1339, 0.20; CAB, 0.20; AM7, 0.016; and dichloromethane, 9.58. The composition was dissolved, coated, and imaged as in Example 1. At 0.38 J/cm 2 , bright magenta lines about 8 micron wide were obtained on the receptor sheet. Example 3 A coating solution containing the following ingredients, was made up: Red P-1339, 0.20; Lexan® 1500, 0.20; AM8, 0.016; and dichloromethane, 9.58. The composition was dissolved, coated, and imaged as in Example 1. At 0.38 J/cm 2 , bright magenta lines about 8 micron lines were obtained on the receptor sheet. Example 4 A coating solution containing the following ingredients, was made up: Red P-1339, 0.20; CAB, 0.20; AM8, 0.016, and dichloromethane, 9.58. The composition was dissolved, coated, and imaged as in Example 1. At 0.38 J/cm 2 , bright magenta lines about 8 micron wide were obtained on the receptor sheet. Example 5 A coating solution containing the following ingredients, was made up: Red P-1339, 0.20; Lexan® 1500, 0.20; AM13, 0.016; and dichloromethane, 9.58. The composition was dissolved, coated, and imaged as in Example 1. At 0.38 J/cm 2 , bright magenta lines about 8 micron lines were obtained on the receptor sheet. Example 6 A coating solution containing the following ingredients, was made up: Red P-1339, 0.20; CAB, 0.20; AM13, 0.016, and dichloromethane, 9.58. The composition was dissolved, coated, and imaged as in Example 1. At 0.38 J/cm 2 , bright magenta lines about 8 micron wide were obtained on the receptor sheet.

Claims: WHAT IS CLAIMED IS: 1. A donor element for a laser-induced thermal transfer process, said donor element comprising a support bearing thereon a colorant layer, said colorant layer comprising a colorant and an infra-red absorbing material, said infra-red absorbing material having the structure: wherein: R l , R 2 , R 3 , and R 4 are each independently hydrogen; substituted or unsubstituted alkyl, acyl, alkyoxyl, aryloxyl, acyloxyl, acylamido, alkylamino, arylamino, or sulfonyl containing 1 to 8 carbon atoms; halogen; cyano; or substituted or unsubstituted phenyl; or (Ri and R 2 ) , (R 2 and R 3 ) , or (R 3 and R 4 ) are joined to form a five-, six-, or seven-membered substituted or unsubstituted aliphatic, aromatic, or heteroaromatic ring; R 5 , R6, R7, and Rβ are each independently hydrogen; substituted or unsubstituted alkyl, acyl, alkyoxyl, aryloxyl, acyloxyl, acylamido, alkylamino, arylamino, or sulfonyl containing 1 to 8 carbon atoms; halogen; cyano; or substituted or unsubstituted phenyl; or (R5 and R 7 ) or (R3 and R 4 ) are joined to form a five-, six-, or seven- membered substituted or unsubstituted aliphatic, aromatic, or heteroaromatic ring; Rg and Ri are each independently alkyl of 1 to 6 carbon atoms; or (R 7 and Rg) or (Rβ and Ri) are joined to form a five-, six-, or seven-membered .substituted or unsubstituted ring; or (Rg and Ri) are joined to form a five-, six-, or seven- membered ring; and X is C=C(CN)2, CO, or SO2. 2. The donor element of claim 1 wherein X is C=C(CN)2. 3. The donor element of claim 2 wherein Ri, R 2 , R 3 , and R 4 are independently hydrogen, chloro, methyl, ethyl, methoxy, ethoxy, on cyano; R 5 and R are each independently hydrogen, alkyl, alkoxyl, chloro, or acylamido; and R 7 and Rβ are each hydrogen and Rg and Ri are each independently alkyl of 1 to 6 carbon atoms, or (R 7 and Rg) or Rβ and Ri) are joined to form a six- membered substituted or unsubstituted ring. 4. The donor element of claim 3 wherein Ri, R 2 , R 3 , and R 4 are each hydrogen; R 5 and R 6 are each independently hydrogen or acylamido; and R 7 and Rβ are each hydrogen and Rg and Ri are each independently alkyl of 1 to 4 carbon atoms, or (R 7 and Rg) or (Rβ and Ri) are joined to form a six-membered unsubstituted ring. 5. The donor element of claim 4 wherein R5 is hydrogen and Rβ is acetamido. 6. A thermal transfer assemblage for a laser- induced thermal transfer process, said thermal transfer assemblage comprising: (a) a donor element comprising a support bearing thereon a colorant layer, said colorant layer comprising a colorant and an infra-red absorbing material, said infra-red absorbing material having the structure: wherein: i, R2, 3, and R 4 are each independently hydrogen; substituted or unsubstituted alkyl, acyl, alkyoxyl, aryloxyl, acyloxyl, acylamido, alkylamino, arylamino, or sulfonyl containing 1 to 8 carbon atoms; halogen; cyano; or substituted or unsubstituted phenyl; or (Ri and R 2 ) , (R 2 and R 3 ) , or (R 3 and R 4 ) are joined to form a five-, six-, or seven-membered substituted or unsubstituted aliphatic, aromatic, or heteroaromatic ring; R 5 , R6, R7, and Rβ are each independently hydrogen; substituted or unsubstituted alkyl, acyl. alkyoxyl, aryloxyl, acyloxyl, acylamido, alkylamino, arylamino, or sulfonyl containing 1 to 8 carbon atoms; halogen; cyano; or substituted or unsubstituted phenyl; or (R 5 and R7) or (R3 and R 4 ) are joined to form a five-, six-, or seven- membered substituted or unsubstituted aliphatic, aromatic, or heteroaromatic ring; Rg and Ri are each independently alkyl of 1 to 6 carbon atoms; or (R 7 and Rg) or (Rβ and Ri) are joined to form a five-, six-, or seven-membered substituted or unsubstituted ring; or (Rg and Ri) are joined to form a five-, six-, or seven- membered ring; and X is C=C(CN)2, CO, or SO 2 and (b) a receptor sheet. 7. The assemblage of claim 6 wherein X is C=C(CN)2. 8. The assemblage of claim 7 wherein Ri, R 2 , R 3 , and R 4 are independently hydrogen, chloro, methyl, ethyl, methoxy, ethoxy, on cyano; R 5 and Rβ are each independently hydrogen, alkyl, alkoxyl, chloro, or acylamido; and R 7 and Rβ are each hydrogen and Rg and Ri are each independently alkyl of 1 to 6 carbon atoms, or (R 7 and Rg) or (Rβ and Ri) are joined to form a six- membered substituted or unsubstituted ring. 9. The assemblage of claim 8 wherein Ri, R 2 , R 3 , and R 4 are each hydrogen; R 5 and Rβ are each independently hydrogen or acylamido; and R 7 and Rβ are each hydrogen and Rg and Ri are each independently alkyl of 1 to 4 carbon atoms, or (R 7 and Rg) or (Rβ and Ri) are joined to form a six-membered unsubstituted ring. 10. The assemblage of claim 9 wherein R 5 is hydrogen and Rβ is acetamido.

Inventors: KELLOGG REID E, MA SHEAU HWA, KELLOGG, REID, E., MA, SHEAU, HWA
Applicants: DU PONT, E.I. DU PONT DE NEMOURS AND COMPANY
Application year: 1992
Main classification: B41M5
IPC codes: B41M5, C09B55