RU2152636C1 - Composition changing color and methods of its usage - Google Patents

Abstract

FIELD: optics. SUBSTANCE: painted composition includes absorber of ultraviolet radiation, substance forming molecular inclusions and having structure with one cavity as minimum and dye changing its color irreversibly under ultraviolet radiation. Toner for electro-photographic process can carry mentioned painted composition and carrier. In general case ultraviolet radiation has wave length of 100-375 nm and presents noncoherent pulse ultraviolet radiation from discharge lamp with dielectric barrier. Dye and absorber of ultraviolet radiation can be related to substance forming molecular inclusions. In this case this dye can be encapsulated at least partially in cavity of substance forming molecular inclusions. Dye can be covalently tied up with absorber of ultraviolet radiation. Backing with applied pattern can be formed with the aid of painted composition. Absorber of ultraviolet radiation includes sensitizer selectively absorbing radiation and photographic initiator. EFFECT: provision for simple ecologically pure method of re-processing of paper for its multiple usage. 77 cl, 5 dwg, 6 tbl

Description

 The invention relates to a modifiable ink composition that, in some embodiments, can be used in an electrophotographic toner, for example, a toner used in a reproduction apparatus that is based on image transfer xerography.

 Electrophotography is generally defined as a process in which, by absorbing photons, an electrical analogue is created, similar to the original. The electrical analogue, in turn, is transformed using a series of operations that result in a physical image. The most common form of electrophotography currently in existence is called image transfer xerography. Despite the fact that it was first demonstrated by C. Carlson in 1938, this process slowly gained recognition. Today, however, image transfer xerography is the backbone of a multi-billion dollar industry.

 The central part of the process is the photoreceptor, which is usually a movable structural element, which, as a rule, takes the form of either a drum or a continuous seamless belt. Ions produced by a corona discharge device accumulate on the surface of the photoreceptor. Ions create a uniform electric field perpendicular to the surface of the photoreceptor, and a uniformly distributed layer of electric charge on its surface. The image of the illuminated original is projected using a lens system and focuses on the photoreceptor.

 Light incident on the charged surface of the photoreceptor leads to an increase in conductivity in the direction perpendicular to the surface of the photoreceptor, and to the concomitant neutralization of surface charges. Unlit areas of the photoreceptor surface retain their charges. The resulting picture of surface charges is a latent electrostatic image.

 A thermoplastic colored powder or toner, the particles of which carry a charge opposite to the charge on the surface of the photoreceptor, is supplied to the photoreceptor, thereby allowing the toner particles to be attracted by charged regions on the surface of the photoreceptor. As a result, a physical image is formed on the surface of the photoreceptor, consisting of electrostatically held toner particles.

 A flat sheet of paper is brought into physical contact with a photoreceptor carrying toner particles. An electric charge applied to the back of the paper draws the toner image to the paper. The image is a positive image of the original. Then the paper is removed from the photoreceptor, and the image from the toner is held on it by electrostatic attraction. The image created by the toner is irreversibly melted into the paper using appropriate heating devices, such as hot-press rolls or an emitter.

 Due to the incomplete transfer of toner to the paper, it is necessary to clean the surface of the photoreceptor from the remaining toner. This toner is removed with a brush, cloth or blade. A corona discharge or the application of an electric field of reverse polarity helps remove toner. Then the photoreceptor is illuminated with a light source creating a uniform light flux in order to neutralize the charges remaining from the previous image creation cycle, thereby completely destroying the previous electrostatic image and preparing the photoreceptor surface for the next cycle.

 Typically, the toner consists of particles of thermoplastic powder having an average diameter of 1-15 microns. Black toner, as a rule, contains 5-10 wt.% Particles of carbon black with a diameter of less than 1 micron dispersed in a thermoplastic powder. For toners used in color xerography, carbon black can be replaced with blue-green, purplish-red, or yellow pigments. The concentration and dispersion of the pigment should be selected so as to impart conductivity to the toner used in the development system. Most development processes require toner that can hold the charge imparted to it by contact electrification for a long time. The thermoplastic used in toner is selected mainly based on its melting ability. Thermoplastics should melt in a relatively narrow temperature range, while being stable during storage and able to withstand the intense shaking that occurs in xerographic developing chambers.

 The success of electrophotography, and in particular x-ray imaging, is no doubt a significant factor in the effective dissemination of information, which has become an integral part of the global communications system. He also contributed to the production of huge quantities of paper, which ultimately must be either destroyed or recycled for later use. Although paper recycling technology does exist, it is nevertheless expensive, time consuming, and is accompanied by waste that must be disposed of appropriately. A common method for processing paper for later use involves converting it into a pulp and treating the pulp to remove ink, toner, and other coloring materials, i.e. "discoloration" of paper is an expensive and not always completely successful operation. Moreover, "bleaching" leads to the appearance of wastewater, which is usually discharged into sedimentation tanks. Then, the obtained “colorless” pulp, often with at least some fresh pulp, is used to produce paper, paperboard, cellulosic packaging materials, etc. The simplest form of processing, however, would have to leave the paper intact, except Thus, the need for its transformation into pulp. For this purpose, toners for copy machines have been created, which become colorless when irradiated with radiation from the near infrared or infrared region. Although the lower boundary of the spectrum of solar radiation lies at about 375 nm, it has a significant infrared component near the upper boundary of the spectrum. Therefore, such toners have a serious drawback - instability in the presence of environmental factors such as sunlight and heat, i.e. such toners become colorless. This result is unsatisfactory because documents may become illegible before their action or need for them disappears. Therefore, there is a need for toners for copy machines that would allow paper to be recycled without damaging it and which would be resistant to commonly encountered environmental factors.

 For example, from US 5,028,792 A, 1991, a colored composition is known containing a color-changing dye and an ultraviolet absorber, however, it does not allow the processing of paper at low cost for its subsequent use.

 The creation of such a composition is the object of the present invention.

 This problem is solved in that the colored composition, containing a color-changing dye and an ultraviolet absorber, further comprises a substance forming molecular inclusions and having a chemical structure with at least one cavity.

 The substance forming the molecular inclusions can be selected from the group consisting of clathrates, zeolites and cyclodextrins.

 The color-changing dye and the ultraviolet absorber may be associated with a substance that forms molecular inclusions.

 The dye may be at least partially enclosed in the cavity of the substance forming the molecular inclusions.

 An ultraviolet absorber may be associated with a substance forming molecular inclusions outside its cavity.

 The ultraviolet absorber can be covalently bound to a substance that forms molecular inclusions.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 A selectively absorbing sensitizer may be covalently linked to a photoinitiator.

 The selectively absorbing radiation sensitizer can absorb ultraviolet radiation with a wavelength of from about 100 to about 375 nm.

 Ultraviolet radiation may be incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.

 The selectively absorbing radiation sensitizer may be selected from the group consisting of phthaloylglycine and 4- (4-hydroxyphenyl) -2-butanone.

 The photoinitiator may be selected from the group consisting of [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one- and cyclohexylphenylketone ester.

 The ultraviolet absorber may be selected from the group consisting of phthaloylglycyl-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one, phthaloylglycyl-cyclohexyl-phenylketone ester, 4- (4- oxyphenyl) - 2-butanone-1- [4- (2-hydroxy-ethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one ether, and 4- (4-hydroxyphenyl) -2-butanonecyclohexyl-phenylketone ester .

 The color-changing dye may be covalently linked to an ultraviolet absorber.

 The substance forming the molecular inclusions can be covalently linked to several ultraviolet absorbers.

 The color-changing colorant may be covalently bound to a substance that forms molecular inclusions.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 A selectively absorbing sensitizer may be covalently linked to a photoinitiator.

 A selectively absorbing radiation sensitizer can absorb ultraviolet radiation having a wavelength of from about 100 to about 375 nm.

 Ultraviolet radiation may be incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.

 The selectively absorbing radiation sensitizer may be selected from the group consisting of phthaloylglycine and 4- (4-hydroxyphenyl) -2-butanone.

 The photoinitiator may be selected from the group consisting of [4- (2-hydroxyethoxy) phenyl-2-hydroxy-2-methylpropan-1-one and cyclohexyl-phenylketone ester.

 The ultraviolet absorber may be selected from the group consisting of phthaloylglycyl-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one, phthaloylglycyl-cyclohexyl-phenylketone ester, 4- (4- hydroxyphenyl) -2-butanone-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one ether, and 4- (4-hydroxyphenyl) -2-butanonecyclohexyl-phenylketone ester.

 From US 5028792 A, 1991, there is known a method for changing the color of a colored composition, in which the colored composition contains a color-changing dye and an ultraviolet absorber, the method comprising the step of irradiating the colored composition with ultraviolet radiation with an intensity sufficient to irreversibly change the color of the dye. However, this method does not allow the processing of paper with low costs for its subsequent use, the development of such a method is also an object of the present invention.

 This problem is solved in that in a method for changing the color of a colored composition, in which the colored composition contains a color-changing dye and an ultraviolet absorber, comprising the step of irradiating the colored composition with ultraviolet radiation with an intensity sufficient to irreversibly change the color of the dye, the colored composition further comprises a substance forming molecular inclusions and having a chemical structure with at least one cavity.

 The dye and ultraviolet absorber can be associated with a substance that forms molecular inclusions.

 The method may further include the step of applying the colored composition to the substrate before irradiating the colored composition with ultraviolet radiation.

 Ultraviolet radiation can have essentially one wavelength corresponding to the maximum absorption of the ultraviolet absorber.

 The ultraviolet absorber may have an absorption maximum at a wavelength in the range of from about 100 to about 375 nm, and the ultraviolet absorber can be irradiated with incoherent pulsed ultraviolet radiation, which can have essentially one wavelength corresponding to the maximum absorption of the ultraviolet absorber.

 The color-changing dye may be covalently linked to an ultraviolet absorber.

 Incoherent pulsed ultraviolet radiation may be radiation from a discharge excimer lamp with a dielectric barrier.

 The radiation may have a wavelength of 222 nm.

 The radiation may have a wavelength of 308 nm.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 Toner for an electrophotographic process is known from EP 0542286 A1, 1993, which contains a color-changing dye, an ultraviolet absorber and a carrier thereof. However, this toner does not allow the processing of paper with low costs for its subsequent use. The development of such a toner is also an object of the present invention.

 This problem is solved in that the toner for the electrophotographic process, containing a color-changing dye, an ultraviolet absorber and a color-changing dye and ultraviolet absorber, further comprises a substance that forms molecular inclusions and has a chemical structure with at least one cavity.

 The carrier may contain a polymer.

 The toner may further comprise a charge carrier.

 An ultraviolet absorber can absorb ultraviolet radiation with a wavelength of from about 100 to 375 nm.

 Ultraviolet radiation can be incoherent pulsed radiation from a discharge excimer lamp with a dielectric barrier.

 The color-changing dye and the ultraviolet absorber may be associated with a substance that forms molecular inclusions.

 The color-changing dye may be at least partially enclosed within the cavity of the molecular inclusion substance.

 The ultraviolet absorber can be covalently bound to a substance that forms molecular inclusions.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 An electrophotographic process is known from EP 0542286 A1, 1993, including creating an image on the surface of the photoreceptor, applying toner to the surface of the photoreceptor to create an image from a toner that repeats the original image, wherein the toner contains a color-changing dye, an ultraviolet absorber and a carrier, transferring the image from the toner onto the substrate and fixing the toner image on the substrate. However, this process does not allow the processing of paper with low costs for its subsequent use. The development of such a process is also an object of the present invention.

 This problem is solved in that in an electrophotographic process, including creating an image on the surface of the photoreceptor, applying toner to the surface of the photoreceptor to create an image from a toner that repeats the original image, the toner containing a color-changing dye, an ultraviolet absorber and a carrier, transferring the image from the toner on the substrate and fixing the image of the toner on the substrate, the toner further comprises a substance that forms molecular inclusions and Commercially chemical structure with at least one cavity.

 The carrier may contain a polymer.

 The toner may further comprise a charge carrier.

 An ultraviolet absorber can absorb ultraviolet radiation with a wavelength of from about 100 to about 375 nm.

 Ultraviolet radiation may be incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.

 The color-changing dye and the ultraviolet absorber may be associated with a substance that forms molecular inclusions.

 The color-changing dye may be at least partially enclosed within the cavity of the molecular inclusion substance.

 The ultraviolet absorber can be covalently bound to a substance that forms molecular inclusions.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 An electrophotographic process is known from EP 0542286 AI, 1993, including creating a substrate with a first image deposited on it, formed by a first toner containing a color-changing dye, an ultraviolet absorber and a dye carrier and an ultraviolet absorber, irradiating the first image on the substrate with ultraviolet radiation, creating a second image on the surface of the photoreceptor, applying a second toner to the surface of the photoreceptor to create an image from the toner, which toryaet second image, shifting the second image of the toner, repeating a second image on a substrate and fixing the second toner image on the substrate. However, this process does not allow the processing of paper with low costs for its subsequent use. The development of such a process is also an object of the present invention.

 This problem is solved by the fact that in an electrophotographic process, including creating a substrate with a first image deposited on it, formed by a first toner containing a color-changing dye, an ultraviolet absorber and a dye carrier and an ultraviolet absorber, irradiating the first image on the substrate with ultraviolet radiation, creating a second images on the surface of the photoreceptor, applying a second toner to the surface of the photoreceptor to create an image from the tone a, which repeats the second image, transferring the second image from the toner repeating the second image to the substrate, and fixing the second image from the toner to the substrate, the first toner further comprises a substance forming molecular inclusions and having a chemical structure with at least one cavity, and the first the image on the substrate is irradiated with ultraviolet radiation with an intensity sufficient to irreversibly change the color of the dye.

 The carrier may contain a polymer.

 The first toner may further comprise a charge carrier.

 An ultraviolet absorber can absorb ultraviolet radiation with a wavelength of from about 100 to about 375 nm.

 Ultraviolet radiation may be incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.

 The second toner may comprise a second dye-changing dye, a second ultraviolet absorber and a second carrier of a second dye-changing dye and a second ultraviolet absorber.

 The second carrier may be a polymer.

 The second toner may comprise a charge carrier.

 The second toner may further comprise a substance that forms molecular inclusions.

 Ultraviolet radiation can have a wavelength of from about 100 to about 375 nm.

 The second ultraviolet absorber can absorb ultraviolet radiation with a wavelength of from about 100 to about 375 nm.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 From WO 93/06597 A1, 1993, a printed image substrate is known which is formed by a colored composition comprising a color-changing dye and an ultraviolet absorber. However, the known substrate, which can be, for example, paper, cannot be recycled at low cost for its subsequent use. The low cost processing backing is also an object of the present invention.

 This problem is solved in that in a substrate with a printed image, which is formed by a colored composition containing a color-changing dye and an ultraviolet absorber, the colored composition additionally contains a substance that forms molecular inclusions and has a chemical structure with at least one cavity.

 The substance forming the molecular inclusions can be selected from the group consisting of clathrates, zeolites and cyclodextrins.

 The color-changing dye and the ultraviolet absorber may be associated with a substance that forms molecular inclusions.

 The color-changing dye may be covalently linked to an ultraviolet absorber.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 From EP 0542286 A1, 1993, a substrate is known with an image deposited on it, which is formed by an electrophotographic toner, the electrophotographic toner comprising a color-changing dye, an ultraviolet absorber and a carrier for the dye and ultraviolet absorber. However, the known substrate, which can be, for example, photocopy paper, cannot be reused. A reusable substrate is also an object of the present invention.

 This problem is solved by the fact that in the substrate with the image deposited on it, which is formed by electrophotographic toner, the electrophotographic toner contains a color-changing dye, an ultraviolet radiation absorber and a carrier for a dye and an ultraviolet radiation absorber, the toner additionally contains a substance forming molecular inclusions and having chemical structure with at least one cavity.

 The carrier may be a polymer.

 The toner may further comprise a charge carrier.

 The substance forming the molecular inclusions can be selected from the group consisting of clathrates, zeolites and cyclodextrins.

 The color-changing dye and the ultraviolet absorber may be associated with a substance that forms molecular inclusions.

 An ultraviolet absorber may include a selectively absorbing sensitizer coupled to a photoinitiator.

 An ultraviolet absorber comprising a selectively absorbing sensitizer is known from W093 / 06597 A1, 1993. However, the known absorber does not allow to achieve a high radiation absorption efficiency. Increasing the efficiency of the absorber is also an object of the present invention.

 This problem is solved in that the ultraviolet absorber, including selectively absorbing radiation sensitizer, further comprises a photoinitiator.

 A selectively absorbing sensitizer may be covalently linked to a photoinitiator.

 The selectively absorbing radiation sensitizer can absorb ultraviolet radiation with a wavelength of from about 100 to about 375 nm.

 Ultraviolet radiation may be incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.

 The selectively absorbing radiation sensitizer may be selected from the group consisting of phthaloylglycine and 4- (4-hydroxyphenyl) -2-butanone.

 The photoinitiator may be selected from the group consisting of [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one and cyclohexylphenylketone ester.

 The scavenger may be phthaloylglycyl-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one.

 The absorber may be phthaloylglycyl-cyclohexylphenylketone ether.

 The scavenger may be 4- (4-hydroxyphenyl) -2-butanone-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-propan-1-one ether.

 The scavenger may be 4- (4-hydroxyphenyl) -2-butanone-cyclohexyl-phenylketone ether.

 These and other features and advantages of the present invention will become apparent from the following detailed description, disclosing examples and claims.

FIG. 1 illustrates the complex "ultraviolet radiation absorber, which changes the color of the dye-substance that forms molecular inclusions", in which malachite greens, the ultraviolet radiation absorber - IRGACURE ^® 184 (1-hydroxycyclohexylphenyl ketone), and the substance that forms the molecular inclusions, are taken as the color-changing dye. β-cyclodextrin.

FIG. Figure 2 illustrates the complex “ultraviolet absorber that modifies the dye-substance that forms molecular inclusions”, in which the dye victoria pure blue BO (Basic Blue 7) and the ultraviolet absorber — IRGACURE ^® 184 (1-hydroxycyclohexylphenyl ketone) are used and the substance forming the molecular inclusions is β-cyclodextrin.

 In FIG. Figure 3 shows several excimer lamps emitting radiation with a wavelength of 222 nm and arranged in four parallel columns, where twelve digits indicate the places where twelve intensity measurements were taken at a distance of about 5.5 cm from excimer lamps.

 In FIG. Figure 4 shows several excimer lamps emitting radiation with a wavelength of 222 nm and arranged in four columns, where nine digits indicate the places where nine intensity measurements were taken at a distance of about 5.5 cm from excimer lamps.

 In FIG. Figure 5 shows several excimer lamps emitting radiation with a wavelength of 222 nm and arranged in four parallel columns, with the number "1" indicating the place where ten intensity measurements were taken with increasing distance from the lamps to this place (the measurement results and the distance from the lamps are summarized in table 7).

 The present invention relates generally to a coloring system that changes color when exposed to radiation. The present invention relates to a composition containing a dye that, in the presence of a radiation absorber, changes color. The radiation absorber is capable of absorbing radiation and interacting with the dye, causing a change in the color of the dye.

 More specifically, the composition in accordance with the present invention contains a dye and an absorber of ultraviolet radiation. The dye is selected so that, in the presence of an ultraviolet absorber, the color changes upon exposure to the absorber. The ultraviolet absorber is selected so as to absorb ultraviolet radiation and interact with the dye, causing an irreversible color change of the dye. The term “composition” and options such as “colored composition” are used hereinafter to mean a dye and an ultraviolet absorber. In the case where reference is made to a colored composition that is intended for a particular application, for example, as a toner used in an electrophotographic process, the term “composition based” is used as an option indicating that the material, for example toner, contains a dye, an ultraviolet absorber radiation and, possibly, a substance that forms molecular inclusions.

 In this description, the term "dye" is used to mean, without exception, any material that changes in the presence of an ultraviolet absorber under the influence of the latter. Typically, a colorant is an organic material, such as an organic colorant or pigment, including toners and varnishes. It is desirable that the dye be sufficiently transparent for the ultraviolet radiation with which it is irradiated, or, in other words, does not noticeably interact with it. This term is used to mean a single substance or a mixture of two or more substances.

For the purpose of illustration only, we present the classes of organic dyes, including the malachite green carbinol base (Malachite Green Carbinol base) {4- (dimethylamino) - α [4- (dimethylamino) phenyl] - α phenyl-benzene-methanol}, malachite green carbinol hydrochloride ( Malachite Green Carbinol hydrochloride) {N-4 - [{4- (dimethylamino) phenyl} phenylmethylene] -2,5-cyclohexyldien-1-ylidene] -M-methylmethanaminium chloride or bis- [p- (dimethylamino) phenyl] phenylmethylium chloride} and malachite green oxalate {M-4 - [[4- (dimethylamino) phenyl] phenylmethylene] 2,5-cyclohexyldien-1-ylidene] -M-methyl methanamine chloride or bis [p- (dimethylamino) phenyl] phenylmethylium oxalate}; monoazo-dyes, such as Cyanine Black, Chrysoidine [Basic orange dye 2; 4- (phenylazo) -1,3-benzenediamine monohydrochloride], and β-naphthol orange dye; thiazine dyes such as methylene green, zinc chloride double salt [3.7-bis (dimethylamino) -6-nitrophenothiazin-5-ium chloride, zinc chloride double salt]; oxazine dyes such as Lumichrome (7,8-dimethylalloxazine); naphthalimide dyes such as yellow Lucifer CH {dilithium salt of 6-amino-2- [(hydrazinocarbonyl) amino] -2,3-dihydro-1,3-dioxo-1H-benz- (de) isoquinoline-5,8-disulfonic acids}; azine dyes such as Janus green B (Janus Green B) {3- (diethylamino) -7- [[4- (dimethylamino) phenyl] azo] -5-phenylphenazinium chloride}; cyanine dyes such as Indocyanine Green {Cardio Green or Fox Green; internal sodium salt 2- [7- [1,3-dihydro-1,1-dimethyl-3- (4-sulfobutyl) -2H-benz (e) indol-2-ylidene] -1, 3,5, -heptatrienyl ] -1,1-dimethyl-3- (4-sulfobutyl) -1H-benz (e) indolium hydroxide}; indigo dyes such as Indigo {Indigo Blue or Vat Blue 1; 2- (1,3-dihydro-3-oxo-2H-indol-2-ylidene) -1,2-dihydro-3H-indol-3-one}; coumarin dyes such as 7-hydroxy-4-methylcoumarin (4-methylumbelliferone); benzimidazole dyes such as Hoechst 33258 [bisbenzimide or 2- (4-hydroxyphenyl) -5- (4-methyl-1-piperazylin) -2,5-bi-1H-benzimidazole three hydrochloride pentahydrate]; parachinoid dyes such as Hematoxylin (Hematoxylin) {(Natural Black) 1; 7.1 1b-dihydrobenz (b) indeno [1,2-d] pyran-3,4,6a, 9,10 (6H) -pentol}; fluorescent dyes such as fluoresceinamine (5-aminofluorescin); diazonium salt dyes, such as Diazo Red RC dye (Azoic Diazo N 10 or Fast Red RC salt; 2-methoxy-5-chlorobenzene diazonium chloride, zinc chloride double salt; azoic diazo dyes, such as Fast Blue BB salt (Azoic Diazo N 20; 4-benzylamino-2.5-diethoxybeneol diazonium chloride, zinc double salt; phenylenediamine dyes such as the yellow dye Disperse Yellow 9 [N- (2,4-dinitrophenyl) -1,4-phenylenediamine or Solvent Orange 53]; diazo dyes such as Disperse Orange 13 [Solvent Orange 52; 1-phenylazo-4- (4-hydroxy-phenylazo) naphthalene]; anthraquinone dyes such as Disperse Blue 3 [Cellito n Fast Blue FFR; 1-methylamino-4- (2-hydroxyethylamino) -9,10-anthraquinone], Disperse Blue 14 [Celliton Fast Blue B; 1,4-bis (methylamino) -9,10-anthraquinone], and Alizarin Blue Black 3 (Mordant Black 13); trizazo dyes such as Direct Blue 71 {Benzo Light Blue FFL or Sirius Light Blue BRR; 3 - [(4 - [(4 - [(6-amino-1-hydroxy-3- sulfo-2-naphthalenyl) azo] -6-sulfo-1-naphthalenyl) azo] -1-naphthalenyl) azo] -1,5-naphthalenyl disulfonic acid tetrasodium salt}; xanthine dyes, such as 2,7-dichlorofluorescin; proflavin dyes such as 3,6-diaminoacridine hemisulfate (proflavin); sulfonaphthalene dyes such as Cresol Red (o-cresosulfonaphthalene); phthalocyanine dyes such as copper phthalocyanine (Copper Phthalocyanine) {Pigment Blue 15; (SP-4-1) - [29H, 31H-phthalocyanato (2 -) - N ²⁹ , N ³⁰ , N ³¹ N ³² ] copper}; carotenoid dyes such as trans-beta-carotene (Food Orange 5); carminic acid dyes such as carmine, aluminum or calcium-aluminum carminic acid varnish (7-a-D-glucopyraposyl-9,10-dihydro-3,5,6,8-tetrahydroxy-1-methyl-9,10 dioxo-2-anthracene carboxylic acid); azure dyes such as Azure A [3-amino-7- (dimethylamino) phenothiazin-5-ium chloride or 7- (dimethylamino) -3-imino-3H-phenothiaein hydrochloride]; and acridine dyes such as Acridine Orange [Basic Orange 14; 3,8-bis (dimethylamino) acridine hydrochloride, zinc chloride double salt] and acriflavine (neutral acriflavin; 3,6-diamino-10-methylacridinium chloride mixed with 3,6-acridinodiamine).

 The term “color changing” with respect to the dye means that the position of the maximum absorption of the dye in the visible region of the spectrum is capable of changing under the influence of ultraviolet radiation. In the general case, it is only necessary that this absorption maximum changes to a different absorption maximum, different from that observed before exposure to ultraviolet radiation, and that this change is irreversible. Thus, a new absorption maximum can be inside or outside the visible region of the spectrum. In other words, the dye may change color or become colorless. The latter, of course, is desirable when the dye is used in a coloring composition intended for use as a toner in an electrophotographic process, which involves first discoloring this colored composition and then forming a new image on it.

 In the present description, the term "irreversible" means that the dye does not return to its original color after the termination of exposure to ultraviolet radiation. It is desirable that the dye that has changed color is stable, that is, that radiation normally found in the environment, such as natural or artificial lighting or heat, does not have a noticeable effect on it. Thus, it is desirable that the dye, becoming colorless, remain colorless indefinitely.

 Used in this description, the term "ultraviolet absorber" means any material that is selected to absorb ultraviolet radiation and interact with the dye, causing a change in the color of the dye. In some embodiments, the ultraviolet absorber may be an organic compound. The term “compound” means one substance or a mixture of two or more substances. If two or more substances are used, it is not necessary that all of them absorb ultraviolet radiation at the same wavelength.

 The present invention includes unique compounds capable of absorbing ultraviolet radiation in a narrow wavelength range. These compounds are obtained by combining a selectively absorbing radiation sensitizer and photoinitiator. Photoinitiators often do not efficiently absorb high-energy radiation. Its combination with a selectively absorbing radiation sensitizer gives a resulting compound, which is a specific compound that effectively absorbs radiation in a narrow region of the spectrum. Examples of ultraviolet absorbers are given in examples 5 and 9 of the present invention.

Although the mechanism of interaction of the ultraviolet absorber with the dye is not fully understood, it is believed that interaction with the dye can occur in various ways. For example, an ultraviolet absorber, when absorbed by ultraviolet radiation, can turn into one or more free radicals that interact with the dye. Such generators of free radicals compounds are usually unrelated ketones, some, but not exhaustive examples of which include benzyl dimethyl ketal (commercially available under the name IRGACURE ^® 651, Ciba-Geiqy Corporation, Hawthorne, New York), 1-hydroxycyclohexyl-phenyl-ketone (IRGACURE ^® 500), 2-methyl-1-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one] (IRGA- (CURE ^® 907), 2-benzyl-2-dimethylamino-1- ( 4-morpholinophenyl) butan-1-one (IRGACURE ^® 369) and 1-hydroxycyclohexyl-phenyl-ketone (IRGACURE ^® 184).

Ultraviolet radiation can also initiate electron transfer or a redox reaction between the ultraviolet absorber and the dye. In this case, the ultraviolet absorber may be, but is not limited to, Michler's ketone (p-dimethylaminophenylketone) or benzyltrimethylstannate. Or, the interaction can occur according to the cationic mechanism, in which case the ultraviolet radiation absorber could be, for example, bis (hexafluorophosphate) (DEGACURE ^® K185, Ciba-Geigy Corporation, Hawthorne, New-York), CYRACURE ^® UVI-6990 ( Ciba-Geigy Corporation), which is a mixture of bis [4- (diphenylsulfonio) phenyl] bishexafluorophosphate with related salts of monosulfonium hexafluorophosphate, as well as 5-2,4- (cyclopentadienyl) [1,2,3,4,5, 6- (methylethyl) benzene] iron (II) hexafluorophosphate (IRGACURE ^® 261).

 The term "ultraviolet radiation" is used here to mean electromagnetic radiation with a wavelength in the range from about 4 to 400 nm. Ultraviolet radiation in the range of about 100 to 375 nm is particularly desirable for the present invention. Thus, this term includes radiation from spectral regions commonly referred to as ultraviolet and vacuum ultraviolet. The wavelength ranges attributed, as a rule, to these two regions lie from about 180 to 400 nm and from about 100 to 180 nm, respectively.

 In some embodiments, the molar ratio of the UV absorber to dye will typically be equal to or greater than about 0.5. As a rule, the more effective the ultraviolet absorber is used to absorb ultraviolet radiation and interact with the dye, that is, to transfer the absorbed energy to the dye to effect its irreversible change, the lower this ratio can be. In accordance with modern theories of molecular photochemistry, it is believed that the lower limit of this ratio is 0.5, which is due to the birth of two free radicals per photon. However, as practice shows, probably more than 1, possibly more than about 10 ratios are needed. The present invention, however, is not associated with any particular range of molar ratios. It is important that the absorber is present in an amount sufficient to cause a discoloration of the dye.

 As practice shows, the dye and absorber of ultraviolet radiation should be, apparently, solids. However, any or all of these materials may be liquid. In an embodiment where the colored composition of the present invention is solid, the effectiveness of the ultraviolet absorber is enhanced when the dye and ultraviolet absorber are brought into close contact. For this, thorough mixing of these two components together with other components that may also be present is desirable. Such mixing is carried out by any means well known to those skilled in the art. When the colored composition contains a polymer, mixing is facilitated if the dye and ultraviolet absorber are at least partially soluble in the softened or molten polymer. In this case, the composition is easily prepared, for example, in a twin roll mill. In another case, the colored composition may be a liquid because one or more of its components are liquids.

 In some applications, the colored composition in accordance with the present invention is used, as a rule, in the form of microparticles. In other cases, the particles of the colored composition should be very small. For example, particles of a colored composition suitable for use as a toner in an electrophotographic process typically have an average diameter of 7-15 micrometers, although smaller and larger particles can be used. It is important to note that the particles should be as uniform in size as possible. Methods for producing such particles are well known to those skilled in the art.

 Photochemical processes include the absorption of light quanta or photons by a molecule, such as an ultraviolet absorber, with a transition to a chemically highly active electronic excited state. However, the photon energy, inversely proportional to the radiation wavelength, cannot be absorbed by the molecule until it is equal to the difference in energy between the unexcited or initial state and the excited state. Therefore, until the wavelength range of the ultraviolet radiation to which the colored composition is irradiated does not directly coincide with the aforementioned, at least part of the radiation must have wavelengths that will provide the necessary energy to excite the ultraviolet absorber molecule to such an energy level, which will provide interaction with the dye.

 It follows that the maximum absorption of the ultraviolet absorber should ideally coincide with the wavelength range of ultraviolet radiation in order to increase the efficiency of the color change of the dye. This efficiency will also increase if the wavelength range of ultraviolet radiation is relatively narrow with the maximum absorption of the ultraviolet absorber lying within this range. For this reason, ultraviolet radiation with a wavelength of from about 100 to about 375 nm is particularly suitable. It is desirable that the ultraviolet radiation within this range is incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.

 The term "incoherent pulsed ultraviolet radiation" refers to radiation produced by a discharge excimer lamp with a dielectric barrier (hereinafter referred to as "excimer lamp"). Such a lamp is described, for example, in the literature [3,4]. Excimer lamps were originally developed by ABB Infocom Ltd., Lenzburg, Switzerland. Since then, excimer lamp technology has been owned by Haraus Noblelight AG, Hanau, Germany.

 An excimer lamp emits radiation in a very narrow wavelength range, i.e., radiation that has a half-width of the emission band of about 5-15 nm. This emitted radiation is incoherent and pulsed, and the pulse frequency depends on the frequency of the lamp supplying AC current, which usually lies in the range from about 20 to 300 kHz. Excimer lamps, as a rule, are characterized by a wavelength at which the maximum radiation intensity is observed, it is this characteristic that is given in the present description. Thus, in comparison with most other commercially used sources of ultraviolet radiation, which usually emit in the entire ultraviolet range and even in the visible region of the spectrum, the study of an excimer lamp is noticeably more monochromatic.

 Excimers are unstable molecular complexes that are found only in extreme conditions, such as existing temporarily in special types of gas discharge. Typical examples are molecular compounds of two inert gas atoms or an inert gas atom and a halogen atom. Excimer complexes dissociate in less time than a microsecond and, dissociating, release their binding energy (more precisely, internal energy) in the form of ultraviolet radiation. Known excimers, as a rule, emit in the range from about 125 to 360 nm, depending on the excimer gas mixture.

 Although the dye and the ultraviolet absorber have been described as separate compounds, they can be part of the same molecule. For example, they can be covalently bonded to each other either directly or through a relatively small molecule or spacer. The dye and ultraviolet absorber can also be covalently bound to a large molecule, such as an oligomer or polymer, in particular when the solid colored composition of the present invention is used as a toner in an electrophotographic process. Further, the dye and the ultraviolet absorber can be bound to a large molecule by van der Waals forces and a hydrogen bond in combination with other mechanisms. Other options will be fairly obvious to experts in this field.

 For example, in one example, a composition in accordance with the present invention further comprises a molecular inclusion substance. The term “substance forming molecular inclusions”, as used herein, means any substance with a chemical structure containing at least one cavity. That is, the substance forming the molecular inclusions is a cavity-containing structure. The term “cavity” is used herein to mean any vacancy or space large enough to accept at least a portion of a dye or UV absorber, or both. Thus, the cavity can be a tunnel in a substance forming molecular inclusions, or a cavity in the form of a cavity in such a substance. The cavity may be isolated or independent, or connected to one or more other cavities.

 The substance forming the molecular inclusions may be inorganic or organic in nature. In some embodiments, the chemical structure of such a substance is chosen so as to obtain a complex of substances that form molecular inclusions. Examples of substances that form molecular inclusions, which are given here only by way of illustration, are clathrates or intercalates, zeolites and cyclodextrins. Examples of cyclodextrins include, but are not limited to, alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, hydroxypropyl beta-cyclodextrin, hydroxyethyl beta-cyclodextrin, sulfated beta-cyclodextrin and sulfated gamma cyclodextrin (American Maize-Products Company, Hammond, Indian ) In some embodiments, the molecular includant is cyclodextrin. More specifically, in some embodiments, it is alpha cyclodextrin. In other embodiments, the substance forming the molecular inclusions is beta-cyclodextrin. Not wanting to bind ourselves in any way, we give here, however, the generally accepted opinion that the closer the absorber molecule is to the dye that changes color on the substance that forms molecular inclusions, the more effectively the interaction with the dye occurs, causing it to change. Thus, substances that form molecular inclusions with functional groups that can interact and bind the absorber molecule and which are located close to the “binding” site of the color-changing dye are most desirable.

 The dye and absorber of ultraviolet radiation are associated with a substance that forms molecular inclusions. The term “bound” in its broadest sense means that the dye and the ultraviolet absorber are at least in the immediate vicinity of the substance. For example, the dye and / or the ultraviolet absorber can be held in close proximity to the substance forming the molecular inclusions by means of a hydrogen bond, van der Waals forces, or the like. As an alternative, each of them, or both at once, a dye and an ultraviolet absorber, can be covalently bound to a substance that forms molecular inclusions. In some embodiments, the dye will be bound to the molecular inclusion substance via a hydrogen bond and / or Van der Waals forces or the like, while the ultraviolet absorber is covalently bound to such a substance. In other embodiments, the dye is at least partially enclosed in the cavity of the substance forming the molecular inclusions, and the ultraviolet absorber is located outside its cavity.

 In one embodiment, in which the dye and the ultraviolet absorber are bonded to the molecular inclusion substance, the dye is pure purple, the ultraviolet absorber is dehydrogenated phthaloylglycine-2959, and the beta-cyclodextrin is the molecular inclusion substance. In another embodiment, the practical implementation of the invention, in which the dye and the ultraviolet absorber are associated with the substance forming the molecular inclusions, the dye is pure violet, the ultraviolet absorber is. 4 (4-hydroxyphenyl) butan-2-one-2959 (chlorine substituted), and the substance that forms molecular inclusions is beta-cyclodextrin.

In another embodiment wherein the colorant and the ultraviolet radiation transorber are associated with the material forming molecular inclusion dye is malachite green, the ultraviolet radiation is IRGACURE ^® 184, and the substance forming the molecular inclusion of beta-cyclodextrin as shown in FIG. 1. In yet another embodiment, in which the dye and the ultraviolet absorber are bonded to the substance forming the molecular inclusions, the dye is victoria pure blue BO, the ultraviolet absorber is IRGACURE (R) 184, and the substance that forms the molecular inclusions is beta-cyclodextrin as shown in FIG. 2.

 Examples 5 to 9 disclose a method for preparing and linking these dyes and UV absorbers with beta-cyclodextrins. It should be noted that the methods disclosed in examples 5 to 9 are only one of the ways of preparing and binding these components, and that many other methods known in chemistry can be used. Other methods for preparing and linking such components or any other components that can be used in the present invention for specific components are known to those skilled in the art.

 In practice, the dye of ultraviolet radiation and the substance that forms molecular inclusions are most often solids. However, any or all of such materials may be a liquid. The colored composition may also be a liquid, either in the case where one or more of the components are liquid, or in the case when a solvent is used due to the fact that the substance forming the molecular inclusions is organic in nature. As examples of suitable solvents that are not limited to this, the following can be mentioned: amides, such as H, H-dimethylformamide; sulfoxides such as dimethyl sulfoxide; ketones such as acetone, methyl ethyl ketone and methyl butyl ketone; aliphatic and aromatic hydrocarbons such as hexane, octane, benzene, toluene and xylene; esters such as ethyl acetate; water and the like. When the substance forming the molecular inclusions is cyclodextrin, suitable solvents, in particular, are amides and sulfoxides.

 The present invention also relates to a method for effecting a color change of a dye in a composition prepared in accordance with the present invention. Describing briefly, the method includes irradiating a composition containing a color-changing dye and an ultraviolet absorber with ultraviolet radiation with an intensity that is sufficient to change the dye. As stated above, in one embodiment, the composition further comprises a substance that forms molecular inclusions. In another embodiment, the composition is applied to a substrate before irradiation with ultraviolet radiation.

The intensity or dose of ultraviolet radiation that the dye is irradiated with in accordance with the present invention will generally be that which is necessary to change the color of the dye. The amount of ultraviolet radiation can be easily determined by a person skilled in the art using conventional experimental techniques. Energy density is a measure of the amount of emitted electromagnetic energy that crosses a unit surface and is usually measured in watts per square centimeter (W / cm ² ). The energy density range lies between about 5 and 15 mW / cm ² , more precisely between 8 and 10 mW / cm ² . The magnitude of the dose, in turn, is usually a function of the exposure time and the intensity or flux of radiation from the source that irradiates the colored composition. The latter is regulated by the distance between the composition and the source and, being dependent on the wavelength range of ultraviolet radiation, can vary depending on the atmosphere between the radiation source and the composition. Accordingly, in some examples, it is convenient to irradiate the composition with radiation in a controlled atmosphere or in vacuum, although in the general case neither approach is desirable.

 For example, in one embodiment, the dye in accordance with the present invention changes color when exposed to radiation from excimer lamps with a wavelength of 222 nm. More precisely, the pure violet dye changes color when exposed to the radiation of excimer lamps with a wavelength of 222 nm, located about 5-6 cm from the dye and arranged in four parallel columns with a length of about 30 cm, as shown in FIG. 3 and 4. It must be understood that the indicated lamp arrangement is not critical for a given exposure in accordance with the present invention. Accordingly, one or more lamps can be arranged in any configuration and at any distance, which as a result provides a color change of the dye under the influence of ultraviolet radiation from the lamp. It is easy for a person skilled in the art to determine, using a conventional experimental technique, which configurations and which distances are suitable. It must also be understood that various excimer lamps must be used with various ultraviolet absorbers. An excimer lamp used to change the color of a dye associated with an ultraviolet absorber should produce ultraviolet radiation in the wavelength range that is absorbed by the ultraviolet absorber.

The colored composition in accordance with the present invention can be applied on a substrate or in a substrate. However, if the composition is in a substrate, the substrate must be sufficiently transparent for the ultraviolet radiation that is used
to change the color of the dye. In other words, ultraviolet radiation should not noticeably interact with or be absorbed by the substrate. From a practical point of view, it is important that the composition is usually applied to a substrate, with paper being the most common type of substrate. However, other types of substrates can be used, including, but not limited to, woven and non-woven webs or fabrics, films, and the like.

 The present invention also provides a substrate on which there is an image formed using a composition in accordance with the present invention. Although the present invention relates to any substrate capable of carrying a colored, fixed image thereon, it is desirable that the substrate be paper. Particularly preferred, but non-limiting examples of substrates include photocopy and fax paper.

 As an example implementation of the invention, the composition in accordance with the present invention can be introduced into the toner intended for use in an electrophotographic process. The toner contains a dye, an ultraviolet absorber, and a carrier. The carrier may be a polymer, and the toner, in addition, may contain a charge carrier. The briefly described electrophotographic process includes the steps of creating an image on the photoreceptor surface, applying toner to the photoreceptor surface to form an image from the toner that repeats the original image, transferring the image from the toner to the substrate, and fixing the image from the toner to the substrate. After the toner is fixed on the substrate, the dye in the composition changes color when the substrate is irradiated with ultraviolet radiation with an intensity sufficient to irreversibly change the color of the dye. In some embodiments, the ultraviolet radiation used in the dye coloration method will have a wavelength of from about 100 to 375 nm. In other embodiments, the ultraviolet radiation is incoherent pulsed ultraviolet radiation produced by a discharge excimer lamp with a dielectric barrier. In another example, the toner may further comprise a substance that forms molecular inclusions. In the case where the colored composition is intended to be used as a toner in an electrophotographic process, the composition will also contain a carrier, the nature of which is well known to those skilled in the art. For many applications, the carrier may be a polymer, typically a thermoactive or thermoplastic polymer, the latter being more common.

 The following examples of thermoplastic polymers include, but are not limited to: cap-terminated polyacetals such as poly (oxymethylene) or polyformaldehyde, poly (trichloroacetaldehyde), poly (n-valerian aldehyde), poly (acetaldehyde), poly (propionic aldehyde ) etc; acrylic polymers such as polyacrylamide, poly (acrylic acid), poly (methacrylic acid), poly (ethyl acrylate), poly (methyl methacrylate) and the like; fluorocarbon polymers such as poly (tetrafluoroethylene), perforated ethylene propylene copolymers, ethylene tetrafluoroethylene copolymers, poly (chlorotrifluoroethylene), ethylene chlorotrifluoroethylene copolymers, poly (vinylidene fluoride), poly (vinyl fluoride) and the like; epoxy resins, such as condensation products of ethyl ethylhydrin and bisphenol A; polyamides such as poly (6-aminocaproic acid) or poly (E-caprolactam), poly (hexamethylene adipamide), poly (hexamethylene sebacinamide), poly (11-aminoundecanoic acid) and the like; polyaramides such as poly (amino-1,3-phenyleneaminoisophthaloyl) or poly (m-phenyleneisophthalamide) and the like; polyarylene such as poly-p-xylene, poly (chloro-p-xylene) and the like; polyaryl ethers such as poly (hydroxy-2.6-dimethyl-1.4.-phenylene) or poly (p-phenyl oxide) and the like; polyaryl sulfones such as poly (hydroxy-1.4-phenylene-sulfonyl-1.4-phenyleneoxy-1.4-phenylene-isopropylidene-1. 4-phenylene), poly (sulfonyl-1.4-phenyleneoxy-1.4-phenylene sulfonyl-4.4-biphenylene) and the like ; polycarbonates such as poly (bisphenol A) or poly (carbonyl-dioxi-1,4-phenyl-nitropropylidene-1,4-phenylene) and the like; polyesters such as poly (ethylene terephthalate), poly (tetramethylene terephthalate), poly (cyclohexylene-1.4-dimethylene terephthalate) or poly (oxymethylene-1.4-cyclohexylene-methyleneoxyterephthaloyl) and the like; polyaryl sulfides such as poly (p-phenylene sulfide) or poly (thio-1.4-phenylene) and the like; polyamides such as poly (pyromethyl lithimido-1,4-phenylene) and the like; polyolefins such as polyethylene, polypropylene, poly (1-butene), poly (2-butene), poly (1-pentene), poly (3-methyl-1-pentene), poly (4-methyl 1-pentene), 1.2-poly-1.3-butadiene, 1.4-poly-1.3-butadiene, polyisoprene, polychloroprene, polyacrylonitrile, poly (vinyl acetate), poly (vinylidene chloride), polystyrene and the like; and copolymers of the foregoing compounds, such as acrylonitrile butadiene styrene (ABS) copolymers, styrene p-butyl methacrylate copolymers, ethylene vinyl acetate copolymers and the like.

 Some of the most commonly used thermoplastic polymers include styrene-p-butyl acrylate copolymers, styrene-butadiene copolymers, polycarbonates, poly (methyl methacrylate), poly (vinylidene fluoride), polyamides (nylon-12), polyethylene, polypropylene, ethylene-vinyl acetate copolymers and epoxy resins .

 Examples of thermosetting polymers include, but are not limited to, the following: alkyd resins, such as resins of phthalic anhydride and glycerol, maleic acid and glycerol resins, adipic acid and glycerin resins, as well as phthalic anhydride and pentaerythritol resins; allyl resins in which monomers such as diamyl phthalate, diamylisophthalate, diamyl maleate and chlorodic acid dialyl ester serve as polyester compounds; amino resins such as aniline-formaldehyde resins, ethylene urea-formaldehyde resins, dicyan-diamide-formaldehyde resins, melamine formaldehyde resins and urea-formaldehyde resins; epoxy resins such as cross-linking epichlorohydrinbisphenol A resins; phenolic resins, such as phenol-formaldehyde resins, including novolacs and resols; and thermosetting polyesters, silicones, and urethanes.

 In addition to the dye and the ultraviolet absorber and, if necessary, the carrier, the colored composition in accordance with the present invention may also contain additional components depending on the application for which it is intended. For example, a composition to be used as a toner in an electrophotographic process can optionally contain, for example, charge carriers, stabilizers that prevent thermal oxidation, converters (modifiers) of viscoelastic properties, crosslinking agents, and the like. In addition, the composition to be used as a toner in the electrophotographic process may optionally contain charge control additives, such as a quaternary ammonium salt; flow control additives such as hydrophobic silica, zinc stearate, calcium stearate, lithium stearate, polyvinyl stearate and polyethylene powder; and fillers, such as calcium carbonate, clay and talc, among other additives that are used by specialists in this field. For some applications, the charge carrier will be the main component of the toner. Charge carriers, of course, are well known to those skilled in the art and, as a rule, are polymer coated metal particles. The nature and amount of such additional components in a colored composition is well known to those skilled in the art. In addition, the toner in accordance with the present invention may also contain molecular inclusion, as described above.

 In the case where the colored composition is used as a toner in an electrophotographic process, some options are possible without departing from the scope of the present invention. For example, a composition-based toner can be used to form a first image on a blank sheet of paper. The sheet can then be used again after exposure of the sheet to ultraviolet radiation in accordance with the present invention to make the dye and, as a result, the composition discolored. Then, a second image can be obtained on the sheet. The second image may be formed using a standard known toner, or using a composition containing toner that is either the same or different from the composition containing toner used to form the first image. If toner containing the composition was also used to obtain the second image, the sheet can be used again, with the number of cycles of use limited by layering an already colorless composition on the surface of the paper. Further, any subsequent image can be placed on the other side of the sheet. In other words, the second image does not have to be applied to the same side of the sheet on which the first image was applied.

 In addition, the conversion of the image deposited by the toner containing such a composition into colorless is not necessary to carry out directly on the sheet. For example, sheets with images obtained using toners containing such a composition can be processed in the traditional way. However, instead of the usual bleaching operation, the sheets are exposed to ultraviolet radiation, either before or after being converted to paper pulp. If the sheets are exposed to ultraviolet radiation after being converted to paper pulp, one skilled in the art will appreciate that not a single component of the mass will affect the ability of the ultraviolet absorber to cause the color to dye when exposed to ultraviolet radiation. In this case, colorless toner is simply part of the paper obtained from such a pulp.

 The present invention is further illustrated by examples of its implementation. These examples, however, should not be construed as limiting in any way the nature or scope of the present invention. In the examples, all parts are parts by weight unless otherwise specified.

 Example 1

This example describes the preparation of films consisting of a dye, an ultraviolet absorber, and a thermoplastic polymer. The dye and ultraviolet absorber are ground individually in a mortar. The required amount of ground components is weighed and placed in an aluminum cup along with a weighed amount of thermoplastic polymer. The cup is then placed on a hot plate, the temperature of which is 150 ^o C, and the mixture is stirred until melted. A few drops of the molten mixture are poured onto a steel plate and distributed as a thin film using a microscope slide. Each steel plate was 3 x 5 inches (7.6 cm x 12.7 cm) and was represented by Q-Panel Company, Cleveland, Ohio. The film on the steel plate was determined to have a thickness of about 10-20 microns.

In each example, the dye was malachite green oxalate (Aldrich Chemical Company, Inc., Milwaukee, Wisconsin), which for convenience will be referred to as dye A. The UV absorber ("UVRT") consisted of one or more IRGACURE ^® 500 ("UVRT A "), IRGACURE ^® 651 (" UVRT B ") and IRGACURE ^® 907 (" UVRT C "), each of which has been previously described and obtained from Ciba-Geigy Corporation, Hawthiome, New York. The polymer was one of the following: an epichlorohydrin-bisphenol A epoxy resin ( "Polymer A"), EPON ^® 1004 F (Shell Oil Company, Houston, Texas); poly (ethylene glycol) having a weight average molecular weight of about 8,000 ("Polymer B"), Carbovax 8000 (Aldrich Chemi.cal Company); and poly (ethylene glycol) having a weight average molecular weight of about 4,600 ("Polymer C"), Carbovax 4,600 (Aldrich Chemical Company). A control film was prepared which consisted only of dye and polymer. The compositions of the films are presented in table. 1.

Each film, deposited on a steel plate, was irradiated with ultraviolet radiation. In each case, a steel plate with a film sample deposited on its surface was placed on a moving belt conveyor with an adjustable speed. Three different ultraviolet radiation or lamps were used. Lamp A was an excimer lamp with a wavelength of 222 nm and Lamp B was an excimer lamp with a wavelength of 308 nm, as already described. Lamp C was a melting lamp system having a “D” type bulb (Fusion Systems Corporation, Rockville, Maryland). Excimer lamps were arranged in groups of four cylindrical lamps about 30 cm long, and the lamps were oriented perpendicular to the direction of movement of the conveyor belt. The lamps were cooled using circulating water through a centrally located or inner tube of the lamp, and as a result of this, they operated at a relatively low temperature, i.e. about 50 ^o C. The energy density on the outer surface of the lamp was usually from about 4 to 20 J per 1 m ² (J / m ² ).

 However, such a range really only reflects the possibility of current energy sources based on excimer lamps; in the future, higher energy densities may become real. In the case of lamps A and B, the distance from the lamp to the film sample was 4.5 cm and the conveyor belt speed was maintained at 20 ft / min (0.1 m / s). In the case of lamp C, the tape speed was 14 ft / min (0.07 m / s) and the distance between the lamp and the sample was 10 cm. The results of exposure of the film samples to ultraviolet radiation are collected in Table. 2. With the exception of film F, the table contains the number of passes under the lamp that was required to turn the film into discolored. For film F, the table shows the number of passes made, and in each case the film remained colored (unchanged).

 Example 2

This example describes the preparation of solid colored compositions that are used as toners in an electrophotographic process. In each example, the toner comprises a colorant A, as described in Example 1: DER 667 resin, epichlorohydrin-bisphenol F epoxy resin (Polymer ^{D), EPON ® 1004F (Dow} Chemical Company, Mildland, Michigan); and a charge carrier, carrier A, which consisted of very small metal particles coated with a polymer. An ultraviolet absorber (UVRT) consisted of one or more of UVRT B from Example 1, IRGACURE ^® 369 (UVRT D), and IRGACURE ^® 184 (UVRT E), the last two of the absorber have been described previously and were obtained from Ciba-Geigy Corporation, Hawthorne , New York. In one case, a second polymer, styrene acrylate 1221, a copolymer of styrene and acrylic acid (Hercules Incorporated, Wilmington, Delaware) was also present.

 To prepare toner, the dye, UV absorber and polymer were ground and mixed in a Model 3VV 800E twin roll laboratory mill, 3 inches • 7 inches (7.6 cm • 17.8 cm) (Farrel Corporation, Ansonia, Connecticut). The resulting milled mixture was pulverized in a Micropul spiked hammer mill (RDKleinfeldt, Cincinatti, Ohio) with 0.010 inch openings and then sieved to select particles of the appropriate size in a Sturtvant’s airborne micronizer (RD KIeinfeldi, Cindincio, C to get the so-called pretoner. Then the charge carrier was added to the praetoner, and the resulting mixture was thoroughly mixed. In the table. 3 presents the composition of the pretoners, and in table. 4 - toner compositions.

 Each toner was placed separately in a Sharp Model ZT 50TDI toner cartridge and inserted into either a Sharp Model Z-76 or Sharp Model Z-77 xerographic copy machine (Sharp Electronics Corporation, Mahwah, New Jersey). Images were obtained in the usual way on document paper (business correspondence paper) (Neenah Bond). The sheets carrying the image were then exposed to ultraviolet radiation from lamp B, as described in Example 1. In each case, the image was discolored after one pass.

 Example 3

 Describes the preparation of a substance that forms molecular inclusions of beta-cyclodextrin, containing (1) an ultraviolet absorber covalently linked to cyclodextrin and located outside the cyclodextrin cavity, and (2) a dye bound to cyclodextrin via hydrogen bonds and / or Van der Waals forces .

 A. Acylation of the scavenger by Friedel-Crafts reaction.

A 250 ml three-necked round-bottom reaction flask was connected to a condenser (refrigerator) and a pressure equalizing additional funnel equipped with a nitrogen supply tube. A magnetic stirring rod was placed in a flask. When washing the stream of nitrogen the flask was filled with 10 g (0.05 mol) of 1-hydroxycyclohexyl phenyl ketone (IRGACURE ^® 184, Ciba-Geigy Corporation, Hawthorne, New York), 100 ml of anhydrous tetrahydrofuran (Aldrich Chemical Company, Inc., Milwaukee , Wisconsin) and 5 g (0.05 mol) of succinic anhydride (Aldrich). 6.7 g of dehydrated aluminum chloride (Aldrich) was then added to the constantly stirred flask contents. The resulting reaction mixture was maintained at a temperature of about 0 ^° C. in an ice bath for about one hour, after which the mixture was allowed to warm to ambient temperature for two hours. Then this reaction mixture was poured into a mixture of 500 ml of ice water and 100 ml of diethyl ether. The ether layer was removed after a small amount of sodium chloride was added to the aqueous phase to facilitate phase separation. The ether layer was dried over anhydrous magnesium sulfate. The ether was removed under reduced pressure to obtain 12.7 g (87%) of a white crystalline powder. As shown by nuclear magnetic resonance, the resulting substance was 1-hydroxycyclohexyl-4- (2-carboxyethyl) carbonylphenylketone.

 B. Preparation of an acylated scavenger.

12.0 g of 1-hydroxycyclohexyl-4- (2-carboxyethyl) carbonylphenylketone (0.04 mol), 5.95 g (0.05 mol) thionyl chloride (Aldrich) and 50 ml of diethyl ether were charged into a 250 ml round bottom flask connected to a condenser. The resulting reaction mixture was stirred at 30 ^° C. for 30 minutes, after which the solvent was removed under reduced pressure. The residue, a white powder, was kept at 0.01 Top pressure for 30 minutes to remove the remaining solvent and excess thionyl chloride, resulting in 12.1 g (94%) of 1-hydroxycyclohexyl 4 (2-chloroformylethyl) carbonylphenylketone.

 C. Covalent attachment of an acylated scavenger to cyclodextrin.

A 10 g (9.8 mmol) beta-cyclodextrin (American Maize-Products Company, Hammond, Indiana) was charged into a 250 ml three-necked round-bottomed reaction flask containing a magnetic stirring bar and equipped with a thermometer, a condenser and a pressure equalizing additional funnel having a nitrogen supply tube ), 31.6 g (98 mmol) of 1-hydroxycyclohexyl 4- (2-chloroformylethyl) carbonylphenylketone and 100 ml of N, N-dimethylformamide with constant washing with nitrogen. The reaction mixture was heated to 50 ^° C. and 0.5 ml of thiethylamine was added to it. The reaction mixture was kept at a temperature of 50 ^o C for one hour and then cooled to ambient temperature. In this preparation, no attempt was made to isolate a product, beta-cyclodextrin, to which an ultraviolet absorber was covalently attached (hereinafter referred to as beta-cyclodextrin, an absorber, for convenience).

 The above procedure was repeated in order to isolate the reaction product. At the end of the procedure, the reaction mixture was evaporated in a rotary evaporator until approximately 10% of the original volume was reached. The residue was poured into ice water, to which sodium chloride was then added to separate the product from the solution. The resulting precipitate was removed on a filter and washed with diethyl ether. The solid was dried under reduced pressure to obtain 24.8 g of a white powder. In the third preparation, the residue obtained in a rotary evaporator was placed on the top of a column of about 7.5 cm long containing about 15 g of silica gel. The residue was eluted with N, N-dimethylformamide, and the elution solvent was metered with WHATMAN (R) Flexible-Backed TLC Plates (Catalog N 05-713-161, Fisher Scientific, Pittsburgh, PA). The eluted product was isolated by evaporation of the solvent. The structure of the product was determined by nuclear magnetic resonance.

 D. Binding of the dye to a cyclodextrin absorber. Preparation of a painted composition.

 To a solution of 10 g (estimated to be 3.6 mmol) of a beta-cyclodextrin scavenger in 150 ml of N, N-dimethylformamide in a 250 ml round bottom flask was added at ambient temperature 1.2 g (3.6 mmol) of malachite green oxalate (Aldrich Chemical Company, Inc. , Milwaukee, Wisconsin), hereinafter referred to as convenience, Dye A. This reaction mixture was stirred using a magnetic stirring rod for one hour at ambient temperature. Most of the solvent was then removed in a rotary evaporator, and the residue was eluted from the silica gel column, as already described. The beta-cyclodextrin-absorber complex with the inclusion of Dye A was dropped first in the column, purely separating from both free Dye A and beta-cyclodextrin-absorber. The eluent containing this complex was collected and the solvent was removed in a rotary evaporator. The residue was kept under reduced pressure of 0.01 Top to remove the remaining solvent, to give a blue-green powder.

 E. Change in color of the painted composition.

The beta-cyclodextrin-absorber complex with the inclusion of Dye A was exposed to ultraviolet radiation from two different lamps: lamps A and B. Lamp A was a group of 222 nm excimer lamps arranged in the form of four cylindrical lamps about 30 cm long. The lamps were cooled using circulating water through the central or inner tube of the lamp and, as a result, they worked at a relatively low temperature, i.e. about 50 ^o C. The energy density on the outer surface of the lamp is usually from about 4 to 20 J per 1 m ² . However, such energy densities in reality only reflect the capabilities of currently existing energy sources based on excimer lamps; in the future, higher energy densities may become feasible in practice. The distance from the lamp to the irradiated sample was 4.5 cm. Lamp B was a 500 W Hanovia medium-pressure mercury lamp (Hanovia Lamp Co., Newark, New Jersey). The distance from lamp B to the irradiated sample was about 15 cm.

 A few drops of a solution of the beta-cyclodextrin-absorber complex with the inclusion of Dye A in N, N-dimethylformamide were placed on a TLC plate (thin layer chromatography) and in a small plastic weighing pan. Both samples were irradiated with lamp A and discolored (changed to a discolored state) for 15-20 s. Similar results were obtained with lamp B after 30 seconds.

 The first control sample, consisting of a solution of Dye A and beta-cyclodextrin in N, N-dimethylformamide, was not discolored when using lamp A. The second control sample, consisting of Dye A and 1-hydroxycyclohexyl phenyl ketone in N, N-dimethylformamide, was discolored by a lamp A after 60 s. Upon exposure of the sample after an hour, the color began to appear again. To evaluate the effect of the solvent on discoloration, 50 mg of the beta-cyclodextrin-absorber complex with the inclusion of Dye A was dissolved in 1 ml of solvent. The resulting solution or mixture was placed on a microscope slide and irradiated with lamp A for 1 min. The rate of discoloration, i.e., the time required to make the sample colorless, was directly proportional to the solubility of the complex in solution, as shown in table. 5.

 Finally, 10 mg of the beta-cyclodextrin-absorber complex with the inclusion of Dye A was placed on a microscope slide and ground with a pestle. The resulting powder was irradiated with lamp A for 10 seconds. The powder became colorless. Similar results were obtained with lamp B, but at a lower bleaching rate.

 Example 4

 Due to the fact that during the preparation of the colored composition described in Example 3, it is possible that the acylated acid chloride scavenger can at least partially occupy the cyclodextrin cavity, partially or completely displacing the dye, a modified preparation procedure was carried out. Accordingly, the example describes the preparation of a molecular inclusion in beta-cyclodextrin having (1) a colorant at least partially occupying the cyclodextrin cavity and bonded with hydrogen bonds and / or Van der Waals forces, and (2 ) an ultraviolet absorber covalently bonded to cyclodextrin outside the cyclodextrin cavity.

 A. Binding of dye and cyclodextrin.

 To a solution of 10. Or (9.8 mmol) beta-cyclodextrin in 150 ml of N, N-dimethylformamide was added 3.24 g (9.6 mmol) of Dye A. The resulting solution was stirred at room temperature for one hour. The reaction solution was concentrated in a rotary evaporator to a volume of about one tenth of the original. The residue was passed through a silica gel column, as described in part C of Example 1. The solvent was removed from the eluent under reduced pressure in a rotary evaporator to obtain 12.4 g of a blue-green powder, a beta-cyclodextrin complex with dye A.

 B. Covalent binding of an acylated absorber and a cyclodextrin complex with dye inclusion, preparation of a colored composition.

10 g (9.6 mmol) of the beta-cyclodextrin complex with the inclusion of Dye A, 31.6 g (98 g) were loaded into a 250 ml three-necked round-bottomed reaction flask with a capacity of 250 ml containing a magnetic stirring rod and equipped with a thermometer, a condenser and a pressure equalizing additional funnel equipped with a nitrogen supply tube mmol) 1-hydroxy-cyclohexyl 4- (2-chloroformylethyl) carbonylphenyl ketone prepared as described in Part B of Example 1 and 150 ml of M, M-dimethylformamide under continuous nitrogen purge. This reaction mixture was heated to 50 ^° C. and 0.5 ml of triethylamine was added to it. The reaction mixture was maintained at 50 ^° C. for one hour and then cooled to ambient temperature. After that, the reaction mixture was treated in the same manner as described in part A above, to obtain 14.2 g of a beta-cyclodextrin-absorber complex with dye A, a blue-green powder.

 C. Change the color of the painted composition.

 The procedure described in part E of example 1 was repeated with a beta-cyclodextrin-absorber complex with the inclusion of Dye A, prepared as above in part B, basically with the same results.

 Example 5

Полученный продукт, названный фталоилглицин-2959, имел следующие физические параметры:
ИКС [Nujol Muu] ν_max 3440, 1760, 1680, 1600 cm^-1
dppm 1.64[s] , 4.25[m] , 4.49[m], 6.92[m], 7.25[m], 7.86[m], 7.98[m], 8.06[m] ppm.This example describes a method for preparing an ultraviolet absorber called phthaloylglycyl-2959. The following substances were mixed in a 250 ml three-necked round bottom flask connected to a Dean and Stark adapter with a condenser and two glass stoppers: 20.5 g (0.1 mol) of a selectively absorbing sensitizer, phthaloyl glycyl (Aldrich); 24.6 g (0.1 mol) of the photo-initiator IRGACURE ^® 2959 (Ciba-Geigy, Hawthorne, NY); 100 ml of benzene (Aldrich) and 0.4 g of p-toluenesulfonic acid (Aldrich). The mixture was refluxed for 3 hours, after which 1.8 ml of water was collected. The solvent was removed under reduced pressure to obtain 43.1 g of a white powder. The powder was recrystallized from 30% ethyl acetate in hexane (Fisher) to give 40.2 g (93%) of a white crystalline powder having a melting point of about 153-154 ^° C. The reaction is as follows:

The resulting product, called phthaloyl glycine-2959, had the following physical parameters:
IR [Nujol Muu] ν _max 3440, 1760, 1680, 1600 cm ^-1
dppm 1.64 [s], 4.25 [m], 4.49 [m], 6.92 [m], 7.25 [m], 7.86 [m], 7.98 [m], 8.06 [m] ppm.

 Example 6

 This example describes a method for the dehydration of phthaloyl glycyl-2959 prepared in Example 5.

Полученный продукт реакции имел следующие физические параметры:
ИКС (NUJOL) ν_max 617 cm^-1 (C=C=0).The following substances were mixed in a 250 ml round bottom flask connected to an adapter and a condenser: 21.6 g (0.05 mol) phthaloyl glycyl-2959, 100 ml dehydrated benzene (Aldrich) and 0.1 g p-toluenesulfonic acid (Aldrich). The mixture was refluxed for 3 hours. After 0.7 ml of water was collected in the trap, the solution was removed in vacuo to give 20.1 g (97%) of a white solid. This solid was used without further purification. The reaction boils down to the following:

The resulting reaction product had the following physical parameters:
IR (NUJOL) ν _max 617 cm ^-1 (C = C = 0).

 Example 7

 This example describes a method for producing beta-cyclodextrin, to which covalently linked dehydrated phthaloylglycyl-2959 groups from Example 6 are bonded.

 The following substances were mixed in a 100 ml round bottom flask: 5.0 g (4 mmol) of beta-cyclodextrin (American Maize Product Company, Hammond, Indiana) (referred to in the following reactions as beta-CD), 8.3 g (20 mmol) of dehydrated phthaloylglycyl-2959 , 50 ml of anhydrous DMF, 20 ml of benzene and 0.01 g of p-toluenesulfonyl chloride (Aldrich). The mixture was cooled in an ice-salt bath and stirred for 24 hours. This reaction mixture was poured into 150 ml of weak sodium bicarbonate solution and extracted three times with 50 ml of ethyl ether. The water layer was then filtered to give a white solid containing beta-cyclodextrin with an attached phthaloyl glycyl-2959 group. 9.4 g of product were obtained. Thin layer chromatography (TLC) on a plate with reversible phases using a 50:50 mixture of DMF: acetonitrile showed a peak corresponding to the new product, in contrast to the starting material (see the end of the description).

 Of course, the cyclodextrin molecule has several primary alcohols and secondary alcohols with which phthaloylglycyl-2959 can react. The reaction shown shows only one phthaloylglycine-2959 molecule for purposes of illustration.

 Example 8

 This example describes a method for binding a dye and an ultraviolet absorber to a substance capable of including molecules. More specifically, this example describes a method for binding a pure violet dye to a molecular inclusion substance, beta-cyclodextrin, which is covalently bound to the ultraviolet absorber phthaloylglycine-2959 of Example 7.

The following substances were placed in a 100 ml beaker: 4.0 g of beta-cyclodextrin having a dehydrated phthaloylglycine-2959 group and 50 ml of water. Water was heated to 70 ^o C, while the solution became transparent. Then 0.9 g (2.4 mmol) of dye — pure violet (Aldrich Chemical Company, Milwaukee, WI) was added to the solution, and the solution was stirred for 20 min. Next, the solution was filtered. The filtered precipitate was washed with the filtrate and then dried in a vacuum oven at 84 ^° C. A blue-violet powder was obtained in an amount of 4.1 g (92%). The product obtained by the reaction had the following physical characteristics:
UV spectrum in DMF: λ _max 610 nm (cf cv λ _max 604 nm).

 Example 9

 This example describes a method for producing a 4 (4-hydroxyphenyl) butan-2-one-2959 ultraviolet absorber (chlorine substituted).

Продукт, полученный в реакции, имел следующие физические параметры:
ИКС [Nujol Muu] ν_max 3460, 1760, 1700, 1620, 1600 см^-1
1H [CDCl₃] dppm 1.62[s], 4.2[m], 4.5[m], 6.9[m].The following substances were mixed in a 250 ml round bottom flask connected to a condenser and a magnetic stirring bar: 17.6 g (0.1 mol) of a sensitizer sensitive to a specific wavelength, 4 (4-hydroxyphenyl) butan-2-one (Aldrich Chemical Company, Milwaukee, WI), 26.4 g (0.1 mol) of a photoinitiator, chlorinated IRGACURE ^® 2959 (Ciba-Geigy Corporation, Hawthorne, New York), 1.0 ml of pyridine (Aldrich Chemical Company, Milwaukee, Wl) and 100 ml of anhydrous tetrahydrofuran (Aldrich Chemical Company, Milwaukee , WI). The mixture was refluxed for 3 hours, and the solvent was partially removed under reduced pressure (60% removed). The reaction mixture was then poured into ice water and extracted with two 50 ml aliquots of diethyl ether. After drying over anhydrous magnesium sulfate and removal of solvent, 39.1 g of a white powder remained. Recrystallization of a powder from 30% ethyl acetate in hexane afforded 36.7 g (91%) of a white crystalline powder having a melting point of 142-143 ^° C. This reaction reduces to the following:

The product obtained in the reaction had the following physical parameters:
IR [Nujol Muu] ν _max 3460, 1760, 1700, 1620, 1600 cm ^-1
1 H [CDCl ₃ ] dppm 1.62 [s], 4.2 [m], 4.5 [m], 6.9 [m].

 The ultraviolet absorber obtained in this example, 4 (4-hydroxyphenyl) butan-2-one-2959 (chloro-substituted), can be coupled to beta-cyclodextrin and a dye, such as pure violet, using the methods described in examples 6-8 in which 4 (4-hydroxyphenyl) butan-2-one-2959 (chloro-substituted) is displaced by anhydrous phthaloylglycine-2959, prepared in accordance with the methods of examples 6-8.

 Example 10

This example demonstrates that the 222 nm excimer tubes shown in FIG. 3 give the same intensities on the surface of the substrate 5.5 cm from the lamps at numbered points (places), sufficient to change the dye in the compositions on the surface of the substrate in accordance with the present invention. The lamp 10 comprises a lamp housing 15 with four bulb 20 excimer lamps arranged in parallel; The bulb of 20 excimer tubes is approximately 30 cm long. The tubes are cooled by circulating water through a centrally located or inner tube (not shown), and as a result, the tubes operate at a relatively low temperature, i.e. about 50 ^o C. The energy density on the outer surface of the lamp usually lies in the range from about 4 to 20 J per 1 m ² .

 In the table. Figure 6 shows the intensity values that were obtained using a measuring device located on the surface of the substrate. The points at which the readings indicated by the numbers 1, 4, 7 and 10 were taken were located at a distance of about 7.0 cm from the left edge of the column, as shown in FIG. 3. The reference points, indicated by the numbers 3, 6, 9 and 12, were located at a distance of about 5.5 cm from the right edge of the column, as shown in FIG. 3. The reference points, indicated by the numbers 2, 5, 8, and 11, were located in the center at a distance of about 17.5 cm from each edge of the column, as shown in FIG. 3.

 Example 11

In this example, it is shown that the 222 nm excimer tubes shown in FIG. 4 give the same intensities on the substrate surface 5.5 cm from the lamps at numbered points (places), sufficient to change the dye in the compositions on the surface of the substrate in accordance with the present invention. The lamp 10 includes a lamp housing 15 with four bulb 20 excimer lamps arranged in parallel; The bulb of 20 excimer tubes is approximately 30 cm long. The tubes are cooled by circulating water through a centrally located or inner tube (not shown), and as a result, the tubes operate at a relatively low temperature, i.e. about 50 ^o C. The energy density on the outer surface of the lamp usually lies in the range from about 4 to about 20 J per 1 m ² .

 In the table. Figure 7 shows the intensity values that were obtained using a measuring sensor located on the surface of the substrate. The points at which the readings indicated by the numbers 1, 4 and 7 were taken were located at a distance of about 7.0 cm from the left edge of the column, as shown in FIG. 4. The reference points, indicated by the numbers 3, 6 and 9, were located at a distance of approximately 5.5 cm from the right edge of the column, as shown in FIG. 4. The reference points, indicated by the numbers 2, 5 and 8, were located in the center at a distance of about 17.5 cm from each edge of the column, as shown in FIG. 4.

 Example 12

In this example, the intensity given by the 222 nm excimer tubes shown in FIG. 5, on the surface of the substrate, as a function of the distance from the surface to the lamps, the intensity being sufficient to change the dye in the compositions on the surface of the substrate in accordance with the present invention. The lamp 10 comprises a lamp housing 15 with four bulb 20 excimer lamps arranged in parallel; The bulb of 20 excimer tubes is approximately 30 cm long. The tubes are cooled by circulating water through a centrally located or inner tube (not shown), and as a result, the tubes operate at a relatively low temperature, i.e. about 50 ^o C. The energy density on the outer surface of the lamp usually lies in the range from about 4 to 20 J per 1 m ² .

 In the table. 8 shows the intensity values that were obtained using a measuring device located on the surface of the substrate at point 1, as shown in FIG. 5. Point 1 was located in the center approximately 17 cm from each edge of the column, as shown in FIG. 5.

 Based on the above description, the specialist can conclude that many changes and modifications are possible, not contrary to the spirit and not beyond the scope of the present invention.

Literature
1. Application US N 08/119912 from 09/10/1993.

 2. Application US N 08/103503 from 08/05/1993.

 3. U. Kogelschtz. "Silent discharges for the generation of ultraviolet and vacuum ultraviolet excimer radiation" - Pure and Appl. Chem., 62, N 9, pp. 1667-1674 (1990).

 4. E. EIiasson and U. Kogelschatz. "UV Excimer Radiation from Dielectric-Barrier Discharges" - Appl. Phys. B, 16, pp. 289-303 (1988).

Claims (77)

 1. A colored composition comprising a color-changing dye and an ultraviolet absorber, characterized in that it further comprises a substance that forms molecular inclusions and having a chemical structure with at least one cavity.  2. The colored composition according to claim 1, in which the substance forming the molecular inclusions is selected from the group consisting of clathrates, zeolites and cyclodextrins.  3. The colored composition according to claim 2, in which the color-changing dye and the ultraviolet absorber are associated with a substance that forms molecular inclusions.  4. The colored composition according to claim 3, in which the dye is at least partially enclosed in the cavity of the substance forming the molecular inclusions.  5. The colored composition according to claim 3, in which the ultraviolet absorber is associated with a substance forming molecular inclusions outside its cavity.  6. The colored composition according to claim 5, in which the ultraviolet absorber is covalently linked to a substance that forms molecular inclusions.  7. The colored composition according to claim 1, in which the ultraviolet absorber includes a selectively absorbing radiation sensitizer associated with a photoinitiator.  8. The colored composition according to claim 7, in which the selectively absorbing radiation sensitizer is covalently linked to a photoinitiator.  9. The colored composition according to claim 7, in which the selectively absorbing radiation sensitizer absorbs ultraviolet radiation with a wavelength of from about 100 to about 375 nm.  10. The colored composition according to claim 9, in which the ultraviolet radiation is incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.  11. The colored composition of claim 7, wherein the selectively absorbing sensitizer is selected from the group consisting of phthaloylglycine and 4- (4-hydroxyphenyl) -2-butanone.  12. The colored composition of claim 7, wherein the photoinitiator is selected from the group consisting of [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one and cyclohexylphenylketone ester.  13. The colored composition according to claim 7, in which the ultraviolet absorber is selected from the group consisting of phthaloylglycyl-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one, phthaloiglycyl-cyclohexylphenylketone ether, 4- (4-hydroxyphenyl) -2-butanone-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one ether and 4- (4-hydroxyphenyl) -2- butanonecyclohexyl-phenylketone ester.  14. The colored composition according to claim 1, in which the color-changing dye is covalently linked to an ultraviolet absorber.  15. The colored composition according to claim 6, in which the substance forming the molecular inclusions is covalently bonded to several ultraviolet absorbers.  16. The colored composition according to claim 6, in which the color-changing dye is covalently bound to a substance that forms molecular inclusions.  17. A method for changing the color of a colored composition, in which the colored composition contains a color-changing dye and an ultraviolet absorber, the method comprising the step of irradiating the colored composition with ultraviolet radiation with an intensity sufficient to irreversibly change the color of the dye, characterized in that the colored composition further comprises a substance forming molecular inclusions and having a chemical structure with at least one cavity.  18. The method according to 17, in which the dye and the absorber of ultraviolet radiation are associated with a substance that forms molecular inclusions.  19. The method according to 17, further comprising the step of applying the colored composition to the substrate before irradiating the colored composition with ultraviolet radiation.  20. The method according to p, in which the ultraviolet radiation has essentially one wavelength corresponding to the maximum absorption of the ultraviolet absorber.  21. The method according to 17, in which the ultraviolet absorber has a maximum absorption at a wavelength in the range from about 100 to about 375 nm, and the ultraviolet absorber is irradiated with incoherent pulsed ultraviolet radiation, which has essentially one wavelength corresponding to the maximum absorption UV absorber.  22. The method according to item 21, in which the color-changing dye is covalently linked to an ultraviolet absorber.  23. The method according to item 21, in which the incoherent pulsed ultraviolet radiation is radiation from a discharge excimer lamp with a dielectric barrier.  24. The method according to item 21, in which the radiation has a wavelength of 222 nm.  25. The method according to item 21, in which the radiation has a wavelength of 308 nm.  26. The method according to 17, in which the ultraviolet absorber includes a selectively absorbing radiation sensitizer associated with a photoinitiator.  27. Toner for an electrophotographic process comprising a color-changing dye, an ultraviolet radiation absorber, and a color-changing colorant and an ultraviolet radiation absorber, characterized in that the toner further comprises a molecular inclusion substance and having a chemical structure with at least one cavity.  28. The toner according to item 27, in which the carrier contains a polymer.  29. The toner according to item 27, in which the toner further comprises a charge carrier.  30. The toner according to claim 27, wherein the ultraviolet absorber absorbs ultraviolet radiation with a wavelength of from about 100 to 375 nm.  31. The toner according to claim 30, for which the ultraviolet radiation is incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.  32. The toner according to claim 27, wherein the color-changing dye and the ultraviolet absorber are bonded to a substance that forms molecular inclusions.  33. The toner according to item 27, in which the color-changing dye is at least partially enclosed within the cavity of the substance forming the molecular inclusions.  34. The toner according to claim 27, in which the ultraviolet absorber is covalently bound to a substance forming molecular inclusions.  35. The toner according to claim 27, in which the ultraviolet absorber includes a selectively absorbing radiation sensitizer associated with a photoinitiator.  36. The electrophotographic process, including creating an image on the surface of the photoreceptor, applying toner to the surface of the photoreceptor to create an image from a toner that repeats the original image, the toner containing a color-changing dye, an ultraviolet absorber and a carrier, transferring the image from the toner to the substrate and fixing the image on a substrate, characterized in that the toner further comprises a substance forming molecular inclusions and having a chemical stream at least one cavity.  37. The electrophotographic process according to clause 36, in which the carrier contains a polymer.  38. The electrophotographic process according to clause 36, in which the toner further comprises a charge carrier.  39. The electrophotographic process according to clause 36, in which the ultraviolet absorber absorbs ultraviolet radiation with a wavelength of from about 100 to about 375 nm.  40. The electrophotographic process according to § 39, in which the ultraviolet radiation is incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.  41. The electrophotographic process according to clause 36, in which the color-changing dye and the ultraviolet absorber are associated with a substance that forms molecular inclusions.  42. The electrophotographic process according to paragraph 41, in which the color-changing dye is at least partially enclosed within the cavity of the substance forming the molecular inclusions.  43. The electrophotographic process according to paragraph 41, in which the ultraviolet absorber is covalently bound to a substance that forms molecular inclusions.  44. The electrophotographic process according to clause 36, in which the ultraviolet absorber includes a selectively absorbing radiation sensitizer associated with a photoinitiator.  45. An electrophotographic process, including creating a substrate with a first image deposited on it, formed by a first toner containing a color-changing dye, an ultraviolet absorber and a dye carrier and an ultraviolet absorber, irradiating the first image on the substrate with ultraviolet radiation, creating a second image on the surface of the photoreceptor, applying a second toner to the surface of the photoreceptor to create a toner image that repeats the second image the transfer of the second image from the toner repeating the second image to the substrate and fixing the second image of the toner to the substrate, characterized in that the first toner further comprises a substance forming molecular inclusions and having a chemical structure with at least one cavity, and the first image irradiated with ultraviolet radiation on a substrate is carried out with an intensity sufficient to irreversibly change the color of the dye.  46. The electrophotographic process according to item 45, in which the carrier contains a polymer.  47. The electrophotographic process according to item 45, in which the first toner further comprises a charge carrier.  48. The electrophotographic process according to item 45, in which the ultraviolet absorber absorbs ultraviolet radiation with a wavelength of from about 100 to about 375 nm.  49. The electrophotographic process according to § 48, in which the ultraviolet radiation is incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.  50. The electrophotographic process according to item 45, in which the second toner contains a second color-changing dye, a second ultraviolet absorber and a second carrier of a second color-changing dye and a second ultraviolet absorber.  51. The electrophotographic process of claim 50, wherein the second carrier is a polymer.  52. The electrophotographic process according to item 50, in which the second toner contains a charge carrier.  53. The electrophotographic process according to item 50, in which the second toner further comprises a substance that forms molecular inclusions.  54. The electrophotographic process of claim 50, wherein the ultraviolet radiation has a wavelength of from about 100 to about 375 nm.  55. The electrophotographic process according to item 54, in which the second absorber of ultraviolet radiation absorbs ultraviolet radiation with a wavelength of from about 100 to about 375 nm.  56. The electrophotographic process according to item 45, in which the ultraviolet absorber includes a selectively absorbing radiation sensitizer associated with a photoinitiator.  57. The substrate with the printed image, which is formed by a colored composition containing a color-changing dye and an ultraviolet absorber, characterized in that the colored composition further comprises a substance forming molecular inclusions and having a chemical structure with at least one cavity.  58. The substrate according to § 57, in which the substance forming the molecular inclusions is selected from the group consisting of clathrates, zeolites and cyclodextrins.  59. The substrate according to clause 57, in which the color-changing dye and the ultraviolet absorber are associated with a substance that forms molecular inclusions.  60. The substrate of claim 57, wherein the color-changing dye is covalently linked to an ultraviolet absorber.  61. The substrate according to clause 57, in which the ultraviolet absorber includes a selectively absorbing radiation sensitizer associated with a photoinitiator.  62. The substrate with the image deposited on it, which is formed by electrophotographic toner, and the electrophotographic toner contains a color-changing dye, an ultraviolet absorber and a carrier for a dye and ultraviolet absorber, characterized in that the toner additionally contains a substance that forms molecular inclusions and has chemical structure with at least one cavity.  63. The substrate of claim 62, wherein the carrier is a polymer.  64. The substrate according to item 62, in which the toner further comprises a charge carrier.  65. The substrate according to item 62, in which the substance forming the molecular inclusions is selected from the group consisting of clathrates, zeolites and cyclodextrins.  66. The substrate according to item 62, in which the color-changing dye and the ultraviolet absorber are associated with a substance that forms molecular inclusions.  67. The substrate according to item 62, in which the ultraviolet absorber includes a selectively absorbing radiation sensitizer associated with the photoinitiator.  68. An ultraviolet absorber comprising a selectively absorbing radiation sensitizer, characterized in that the ultraviolet absorber further comprises a photoinitiator.  69. The ultraviolet absorber of claim 68, wherein the selectively absorbing radiation sensitizer is covalently coupled to a fluorine initiator.  70. The ultraviolet radiation absorber of claim 68, wherein the selectively absorbing radiation sensitizer absorbs ultraviolet radiation with a wavelength of from about 100 to about 375 nm.  71. The ultraviolet absorber of claim 70, wherein the ultraviolet radiation is incoherent pulsed ultraviolet radiation from a discharge excimer lamp with a dielectric barrier.  72. The ultraviolet absorber of claim 68, wherein the selectively absorbing sensitizer is selected from the group consisting of phthaloylglycine and 4- (4-hydroxyphenyl) -2-butanone.  73. The ultraviolet absorber of claim 68, wherein the photoinitiator is selected from the group consisting of [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one and cyclohexylphenylketone ether.  74. The ultraviolet absorber of claim 68, wherein the ultraviolet absorber is phthaloylglycyl-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one. phthaloiglycyl cyclohexyl phenyl ketone ester.  75. The ultraviolet absorber of claim 68, wherein the ultraviolet absorber is phthaloiglycylcyclohexyl phenyl ketone ether.  76. The ultraviolet absorber of claim 68, wherein the ultraviolet absorber is 4- (4-hydroxyphenyl) -2-butanone-1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropane-1 -on ether.  77. The ultraviolet absorber of claim 68, wherein the ultraviolet absorber is 4- (4-hydroxyphenyl) -2-butanonecyclohexyl-phenylketone ether. Priorities for items:
08/05/93 according to claims 7 - 10, 14, 19 - 26, 28 - 31, 35, 37 - 40, 44, 46 - 52, 54 - 56, 60 - 61, 63, 64, 67 - 71;
09/10/93 by pp. 1 - 6, 15 - 18, 27, 32 - 34, 36, 41 - 43, 45, 53, 57 - 59, 62, 65, 66;
06/13/94 according to claims 11 - 13, 72 - 77.

Images