MXPA00001316A - Electroluminescent sign - Google Patents

Abstract

Signs including electroluminescent lamps are described. In accordance with one embodiment of the invention, an electroluminescent lamp is coupled to a sign (74) by first forming a rear electrode (56) on a front surface of the sign substrate (52) which may be metal, plastic or cardboard. After forming the rear electrode on the sign, a dielectric layer (62) is screen printed over the rear electrode, and a phosphor layer (64) is screen printed over the dielectric layer. A layer of indium tin oxide (66) is then screen printed over the phosphor layer and a bus bar (68) or front electrode is provided to complete the clamp.

Description

SIGN ELECTROLUMINISCENT FIELD OF THE INVENTION The present invention relates, in general, to electroluminescent lamps and, more especially, to advertising signs that include said lamps.

BACKGROUND OF THE INVENTION Electroluminescent (EL) lamps generally comprise a phosphor layer located between two electrodes, at least one of the light-transmitting electrodes being. Also at least one dielectric is placed between the electrodes, so the lamp works, essentially, as a capacitor. When voltage is applied through the electrodes, phosphorus is activated and emits light. EL lamps are normally manufactured in the form of discrete cells on rigid or flexible substrates. A known method of manufacturing EL lamps comprises the steps of applying a coating of light-conducting material, such as tin and indium oxide, to a back surface of polyester film, applying a phosphor layer to the conductive material, applying to the less a dielectric layer to the phosphor layer, apply a subsequent electrode to the dielectric layer, and apply an insulating layer to the posterior electrode. The different layers can, for example, be laminated by pressure and heat. Alternatively, the different layers can be printed with one another. When a voltage is applied through the tin and indium oxide and the back electrode, the phosphor is activated and emits a light that is visible through the polyester film. Normally, it is not desirable that the entire polyester film be light emitting. For example, if an EL lamp is configured to display a word, it is desirable that only the portions of the polyester film of the lamp corresponding to the letters of the word are light emitting. Accordingly, the tin and indium oxide is applied to the polyester film so that only the parts of the desired film emit light. For example, the entire tin and indium oxide polyester film can be coated, and then parts of the tin and indium oxide can be removed with an acid preparation, leaving discrete illumination zones in place. Alternatively, an opaque ink may be printed on the front surface of the polyester film to prevent light from being emitted through the entire front surface of the film. EL lamps are often installed in products (eg, signs and clocks) to provide lighting for these products. For example, EL lamps are commonly used to provide illuminated images to advertising signs. In particular, and in regard to advertising signs, the EL lamps adhere to the front surface of the advertising sign so that the light emitted by the phosphor layers of said lamps can be seen from a position opposite the sign. Using prefabricated EL lamps to build an illuminated advertising sign is tedious. In particular, each EL lamp must be constructed in the form of an inverted image. For example, when an EL lamp is used to display an illuminated word, for example, "THE", it is important that the word is correctly written, that is, legible from left to right, when viewed from a position opposite. to the sign. Accordingly, and up to now, it was necessary to apply the tin and indium oxide to the polyester film in the form of an inverted image; for example, in the form of an inverted image of "THE". The subsequent phosphorus, dielectric and posterior electrode layers are also applied in the form of inverted images. In addition, it is possible that the EL lamp may be damaged by adhering it to the sign. Accordingly, it would be desirable to provide a method for manufacturing illuminated signs having EL lamps and not requiring the coupling of prefabricated EL lamps to the sign. It would also be desirable that said method facilitate the application of the different layers of the EL lamps to the EL substrate in the form of a direct image, instead of an inverted image.

BRIEF DESCRIPTION OF THE INVENTION Said and other objects can be achieved by means of a sign which, in one embodiment, comprises an electroluminescent lamp formed integrally therewith. In particular, the electroluminescent lamp is formed on the sign, using the sign as a substrate of the EL lamp. More specifically, and in one embodiment, the sign is manufactured following the steps of stenciling a rear electrode on the front surface of the sign, printing with said process at least one dielectric layer on the back electrode, after having printed with stencil the post electrode on the sign, print a layer of phosphor over the dielectric layer to define the desired area of illumination, print a layer of tin and indium oxide ink over the phosphor layer, screen print a layer of background on the sign, so that the background layer substantially surrounds the desired area of illumination, and apply a protective coating over the tin and indium oxide ink and the background layer. More specifically, instead of coupling separate EL lamps to the sign, the rear electrode is printed with stenciling directly on the front surface of the sign, and the other layers of the EL lamp are printed with screen on the rear electrode. The method described above provides an illuminated sign having EL lamps, but does not require coupling prefabricated EL lamps to the sign. Said method also facilitates the application of the different layers of the EL lamps to the EL substrate in the form of a direct image, instead of an inverted image.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a known electroluminescent lamp. Fig. 2 is a flow diagram illustrating a known sequence of steps for manufacturing the electrolminiscent lamp shown in Fig. 1. Fig. 3 is a flow chart illustrating a sequence of steps for manufacturing a sign that contains an EL lamp according to one embodiment of the present invention. Figure 4 is a pictorial illustration of a schematic view of a sign containing an EL lamp manufactured in accordance with the steps indicated in figure 3. Figure 5 is a pictorial illustration of a schematic view of a sign containing three lamps. manufactured according to the steps indicated in figure 3. Figure 6 is a flow diagram illustrating a sequence of steps for the manufacture of a sign containing an EL lamp according to another embodiment of the present invention.

Figure 7 is a pictorial illustration of a schematic view of a sign containing an EL lamp manufactured in accordance with the steps indicated in Figure 6.

DETAILED DESCRIPTION OF THE INVENTION Figure 1 is a schematic illustration of a known electroluminescent (EL) lamp 10 comprising a substrate 12, a front electrode of conductive particles 14, a phosphor layer 16, a dielectric layer 18, a subsequent electrode of conductive particles 20, and a protective coating layer 22. The substrate 12 and the front electrode 14 can be, for example, a polyester layer coated with tin oxide and indium, respectively. The phosphor layer 16 may be formed by electroluminescent phosphor particles (eg, zinc sulphide with addition of copper or manganese) which are dispersed in a polymeric binder. The dielectric layer 18 can be formed of material of high dielectric constant, such as barium titanate dispersed in a polymeric binder. The conductive particle back electrode 20 is formed of conductive particles (e.g., silver or carbon) dispersed in a polymeric binder to form a printable, stencilled ink. The protective coating 22 can be, for example, an ultraviolet (UV) coating, such as U.V. Clear, marketed by Polymeric Imaging, Inc. North Kansas City, Missouri. The EL 10 lamp and the layers constituting it are well known. Referring, now, to Figure 2, the EL 10 lamp is normally manufactured by application 30 of the front electrode 14 (for example, tin and indium oxide) to the back surface of the substrate 12. For example, it can be sprayed onto the film Of polyester. The phosphor layer 16 is then placed on the front electrode 14, and a dielectric layer 18 is placed 34 on the phosphor layer 16. Next, the back electrode 20 is printed with stencil 36 on the dielectric layer 18, and the insulating layer 22 is placed 38 on the back electrode 20 to substantially prevent the possible danger of electrocution or provide a moisture barrier to protect the lamp 10. The various layers can be applied, for example, by lamination by means of heat and Pressure. As explained above, to make an illuminated sign having an EL lamp using known methods, it is necessary to previously manufacture the EL lamp and then to couple the prefabricated EL lamp to the sign. In particular, the insulating layer (eg, the insulating layer 22) of the prefabricated lamp adheres to the front surface of the sign so that, when a voltage is applied across the front and rear electrodes, the phosphorus is activated and emit a light that is visible through the polyester film. Attaching a prefabricated EL lamp to a sign is tedious and requires fabricating the EL lamp in the form of an inverted image.

In Figure 3 a sequence of steps for manufacturing an illuminated sign containing an EL lamp according to one embodiment of the present invention is illustrated. The sign may have, for example, a metal substrate (eg, 0.25 mm gauge aluminum), a plastic substrate (eg, heat stabilized polycarbonate 0.15 mm), or a cardboard substrate (eg, 50 pts cardboard). .) With respect to the 0.25 mm. Aluminum sign, a rear electrode 40 is formed on the front surface of the sign. The back electrode is formed of conductive particles (e.g., silver or carbon) dispersed in a polymeric binder to form a printable, stencilled ink, such as # 7145 HDP217, which is marketed by DuPont Electronics, Reasearch Triangle Park, North Carolina. Next, a dielectric layer is formed on the posterior electrode. The dielectric layer is formed by a material of high dielectric constant (such as barium titanate dispersed in a polymeric binder) which is also marketed by DuPont Electronics, Research Triangle Park, North Carolina. Subsequently, a phosphorus layer of electroluminescent phosphorus particles (eg, zinc sulphide with addition of copper or manganese) dispersed in a polymeric binder is formed on the dielectric layer. Then a layer of tin and indium oxide ink is formed on the phosphor layer, and a protective coating 48 is applied over the tin and indium oxide ink. More specifically, and with reference, now, to Figure 4, a metal sign 50 (for example, a sign having a metallic substrate) is first placed, with a front surface 52 and a rear surface (not shown in the figure). 4), on a printing press with automatic flat screen (not shown in Figure 4). A rear electrode 54 is then stencilled, such as carbon or silver capable of stencil printing, with an illumination zone 56, and a subsequent connection of the electrode 58 on the surface 52 of the electrode 58 is then stencilled. sign 50. The illumination zone 56 defines a graphic pattern or light-emitting form (for example, an "L", representative of the final image to be illuminated on the sign 50. The subsequent connection of the electrode 58 extends from the lighting area 56 to the perimeter 60 of the front surface of the sign 52. The rear electrode 54 is printed with screen in the form of a positive image, or direct image, ie, for example, in the form of "L", instead "L" inverted After the rear electrode 54 is printed on the front surface 52, the rear electrode 54 hardens until it dries, for example, the rear electrode 54 and the sign 50 can be placed in a to grill a rotating oven for approximately two minutes, at a temperature of about 176.6 ° C. A dielectric layer 62 is then stencilled onto the surface of the sign 52 so that the dielectric layer 62 substantially covers the entire illumination zone 56, leaving, however, substantially bare the subsequent connection of the electrode 58. In particular, the dielectric layer 62 contains two layers (not shown) of material with high dielectric constant, such as barium titanate dispersed in a polymeric binder. The first layer of barium titanate is stenciled onto the rear electrode 54 and then hardened to dry for about two minutes at a temperature of about 176.6 ° C. The second layer of barium titanate is then stenciled over the first layer and hardened until it dries for approximately two minutes at a temperature of about 176.6 ° C to form the dielectric layer 62. According to one embodiment, the layer dielectric 62 has substantially the same shape as the illumination zone 56, but is approximately 2% greater than said zone 56. After screen printing the dielectric layer 62 and the rear electrode 54 on the surface of the sign 52, a phosphor layer 64 is printed on the surface of the sign with stenciling. 52, on the dielectric layer 62. The phosphor layer 64 is printed with screen in the form of direct or positive image, ie, for example, in the form of "L", instead of inverted image, ie, for example, in the form of an inverted "L", and has the same shape and size as the illumination zone 56. The phosphor layer 64 can be printed on the sign 50 with, for example, the same stencil used to print the rear electrode 54 on the sign 50. Next, the phosphor layer 64 hardens, during, approximately, two minutes, for example, at about 176.6 ° C. Then a layer of tin oxide and indium 66 is printed on the phosphor layer 64. The tin and indium oxide layer 66 has substantially the same shape and size as the illumination zone 56 and can be printed with, for example , the same stencil used to stamp the phosphor layer 64. The tin and indium oxide layer 66 is also printed as a direct image and hardens, for about two minutes, for example, at about 176.6 ° C. Subsequently, a front electrode, or busbar, 68 made of silver ink, is printed with stencil on the surface of the sign 52, and is configured to transport the energy to the tin and indium oxide layer 66. Specifically, the electrode 68 is printed on the sign surface 52 so that a first part 70 of the front electrode 68 makes contact with the outer perimeter of the tin and indium oxide layer 66 and, therefore, with the outer perimeter of the lighting zone 56, and so that the connection of the front electrode 72 extends from the illumination zone 56 to the perimeter 60 of the surface of the sign 52. Then, the front electrode 68 hardens for approximately two minutes at about 176.6 ° C. The back electrode 54, the dielectric layer 62, the phosphor layer 64, the tin oxide and indium 66 layer, and the front electrode 68 form an EL lamp extending from the surface 52 of the sign 50. Then, it is printed with stencil a bottom layer 74 on the front surface 52 of the sign 50. The bottom layer 74 substantially covers the front surface 52, except for the illumination zone 56 and a terminal tab-shaped portion 76 of the front surface 52. In In particular, the bottom layer 74 substantially covers the front electrode 68, the part of the dielectric layer 62 does not align with the illumination zone 56, and the back electrode 54. The terminal flange-shaped part 76 is adjacent to the perimeter of the sign. 60 and is not covered to facilitate the coupling of a power supply source 78 with the connection of the front electrode 72 and the connection of the back electrode 58. In particular, the bottom layer 74 is printed with seric or on the front surface 52 so that, substantially, only the bottom layer 74 and the tin and indium oxide layer 66 are visible from a location opposite the front surface 52. The bottom layer 74 may contain, example, ink for printing with UV stencil and can be hardened in a UV dryer employing known stencil printing practices for signs. Then, the sign 50 can be embossed so that the front surface of the sign 52 is not planar. In particular, the sign 50 can be embossed so that the illumination zone 56 projects outwardly with respect to the perimeter of the sign 60. Alternatively, the sign 50 can be embossed so that a portion of the illumination zone 56 (e.g. short branch of the "L") is projected outwardly relative to another part of the illumination zone 56 (e.g., the long branch of the "L"). For example, the sign 50 can be placed in a metal press configured to apply seven kilograms of pressure per square millimeter to dimple the front surface of the sign 52. After applying the rear electrode 54, the dielectric layer 62, the layer phosphor 64, the tin oxide and indium layer 66, the front electrode 68 and the bottom layer 74 to the sign 50, this can, for example, be hung from a window, from a wall or suspended from the ceiling. The electric supply 78 is then coupled to the connection of the front electrode 72 and the connection of the back electrode 58, and a voltage is applied through the back electrode 54 and the front electrode 68 to activate the phosphor layer 64. In particular, the The current is transmitted through the front electrode 68 to the tin and indium oxide layer 66, and, through the rear electrode 54, to the illumination zone 56, to illuminate the letter "L". According to one embodiment, the rear electrode 54 has a thickness of approximately 0.6 millimeters, the dielectric layer 62 has a thickness of approximately 1.2 millimeters, the phosphor layer 64 has a thickness of approximately 1.6 millimeters, the tin oxide and indium 66 has a thickness of approximately 1.6 millimeters, the front busbar 68 has a thickness of approximately 0.6 millimeters, and the bottom layer 74 has a thickness of approximately 0.6 millimeters. Of course, the different thicknesses may vary. The method described above provides an illuminated sign having an EL lamp, but which does not require coupling a prefabricated EL lamp thereto. Said method also facilitates the application of each of the layers of the EL lamp to the EL substrate in the form of a positive image, instead of an inverted image. However, the modality described above is illustrative, and is not intended to be limiting. For example, after stenciling the bottom layer 74 on the front surface 52, an ultraviolet (UV) coating may be applied to the sign 50. In particular, the ultraviolet coating may be applied to cover the entire front surface 52 of the sign. 50 and to protect the EL lamp formed by the rear electrode 54, the dielectric layer 62, the phosphor layer 64, the tin and indium oxide layer 66, and the front electrode 68. Similarly, the front surface 52 of the The sign 50 can be coated with a UV coating before applying the back electrode 54 to the front surface 52. For example, if the sign 50 is a cardboard sign, then the UV coating is first applied to the front surface 52 to substantially secure the integrity of the EL lamp layers (for example, to substantially prevent the cardboard substrate from absorbing stencil inks). According to another embodiment of the present invention, a sign containing several EL lamps is provided. For example, Figure 5 is a pictorial illustration of a schematic view of a metal sign 80 with three lamps EL 82A, 82B, and 82C, configured as a circle, a triangle and a square, respectively. The placard 80 comprises a front surface 84 and a back surface (not shown in Figure 5), and is first placed in an automatic flat screen printing press (not shown in Figure 5). Then, a rear electrode 86 (as, for example, carbon or silver capable of stencil printing), with three illumination zones 88A, 88B and 88C, and three electrode connections is printed with stencil on the front surface 84 of the sign 80. posterior 90A, 90B and 90C. The lighting area 88A defines a graphic pattern or shape, for example, a circle, emitting light, representative of the final image to be illuminated by the lamp EL 82A placed on the sign 80. The lighting area 88B defines a graphic pattern or form (for example, a triangle) emitting light, representative of the final image that must be illuminated by the lamp EL 82B placed on the sign 80. The lighting area 88C defines a graphic pattern or shape (for example, a square) emitting light, representative of the final image that must illuminate the EL 82C lamp on the sign 80. The connection of the rear electrode 90A extends between the illumination area 88A and the illumination area 88B. The rear electrode connection 90B extends between the illumination zone 88B and the illumination zone 88C. The back electrode connection 90C extends from the illumination zone 88B to the perimeter 92 of the front surface of the sign 84. The back electrode 86 is printed with screen in the form of a positive or direct image. After printing the back electrode 86 on the front surface 84, the back electrode 86 hardens until it dries. Next, a dielectric layer 94 is printed with stencil on the surface of the sign 84, so that the dielectric layer 94 substantially covers the back electrode 86, while leaving a part of the connection of the back electrode 90 substantially discovered. In particular, the dielectric layer 94 comprises two layers (not shown) of material of high dielectric constant, such as barium titanate dispersed in a polymeric binder. The first barium titanate layer is printed with screen on the back electrode 86 and then hardened until it is dried, for approximately two minutes, at a temperature of about 176.6 ° C. The second layer of barium titanate is printed with screen, then on the first layer of barium titanate, and hardens until it is dried, for approximately two minutes, at a temperature of about 176.6 ° C, to form the dielectric layer 94. According to one embodiment, the dielectric layer 94 has three illumination portions, 96A, 96B, and 96C, which have substantially the same shape as the respective illumination zones 88A, 88B and 88C, and are approximately one 2% greater than the same. In addition, the dielectric layer 94 contains two connecting portions 98A and 98B of suitable dimensions for covering the rear electrode connections 90A and 90B, respectively. After stenciling the dielectric layer 94 and the back electrode 86 to the surface of the sign 84, a phosphor layer 100 is printed on the surface of the sign 84 over the dielectric layer 94. The phosphor layer 100 comprises three layers of phosphorus 100. parts, 102A, 102B and 102C, respectively, which have substantially the same shape and size as the illumination zones 88A, 88B and 88C, respectively. The phosphor layer 100 can be printed on the sign 80 with, for example, the same stencil used to print the back electrode 86 on the sign 80. Then, the phosphor layer 100 hardens during, for example, two minutes, about 176.6 ° C. Next, a layer of tin oxide and indium 104 is printed on the phosphor layer 100. The tin and indium oxide layer 104 contains three parts 106A, 106B, and 106C, respectively, which have substantially the same shape and size than the lighting areas 88A, 88B, and 88C, respectively. The tin and indium oxide layer 104 can be printed with, for example, the same stencil used to print the phosphor layer 100. The tin and indium oxide layer 104 is also printed as a direct image and hardens, during approximately two minutes, for example, at about 176.6 ° C. Subsequently, a front electrode, or bus bar, 108, made of silver ink, is printed with stencil on the surface of the sign 84, and is configured to transport the energy to the tin and indium oxide layer 104. Specifically , the front electrode 108 is printed on the sign surface 84 so that a first part 110A of the front electrode 108 makes contact with the outer perimeter of the part of the tin and indium oxide layer 106A, a second part 110B makes contact with the outer perimeter of the portion of the tin and indium oxide layer 106B, and a third part 110C makes contact with the outer perimeter of the portion of the tin and indium oxide layer 106C. The first part 110A contains a front electrode connection 112A that extends from the illumination zone 88A to the perimeter 92 of the surface of the sign 84.

Similarly, the second part 110B contains a front electrode connection 112B extending from the illumination zone 88B to the perimeter 92 of the surface of the sign 84, and the third portion 110C contains a front electrode connection 112C extending from the illumination zone 88C to the perimeter 92 of the surface of the sign 84. Then, the front electrode 108 hardens for approximately two minutes at about 176.6 ° C. The back electrode 86, the dielectric layer 94, the phosphor layer 100, the tin and indium oxide layer 104, and the front electrode 108 form an EL lamp extending from the surface 84 of the sign 80. Then, it is printed Stenciling a bottom layer 114 on the front surface 84 of the sign 80. The bottom layer 114 substantially covers the front surface 84, except for the illumination zone 88, and a terminal tab-shaped portion 116 of the front surface 84. In particular, the bottom layer 114 substantially covers the front electrode 108, the portion of the dielectric layer 94 does not align with the illumination zones 88A, 88B, and 88C, and the back electrode 86. The terminal eye portion 116 it is adjacent to the sign perimeter 92 and is not covered to facilitate the coupling of a power source 118 with the connection of the front electrode 112 and the connection of the back electrode 90. Specifically, the bottom layer 114 is printed with screen on the front surface 84 so that, substantially, only the bottom layer 114 and the tin and indium oxide layer 104 are visible from a location opposite the front surface 84. The bottom layer 114 it may include, for example, UV stencil ink and may be cured in a UV dryer employing known stencil printing practices. Alternatively, the bottom layer 114 may contain several customary American stencil printing inks, and may be configured in the form of a graphic pattern, such as the bottom layer 120. Thereafter, the sign 80 may be embossed so that the front surface of the sign 84 do not be flat. In particular, the sign 80 can be embossed so that the lighting area 88A projects outwardly relative to the lighting area 88B. Alternatively, the sign 80 can be embossed so that the illumination zone 88B projects outwardly relative to the illumination zone 88A. The signs described above contain EL lamps, but do not require the coupling of prefabricated EL lamps to the sign. Said signs are also manufactured by stenciling each of the layers of the EL lamps in the form of a positive image, instead of an inverted image. Even in accordance with another embodiment, a plastic sign containing EL lamps is provided. In particular, and with reference, now, to Figure 6, a front electrode defining a lighting zone (e.g., "L") (Figure 4) on a rear surface of a plastic placard is printed with stencil 130. transparent. After stenciling 130 the front electrode, a layer of tin oxide and indium is printed with stencil 132 on the back surface, and a layer of phosphorous is printed on the tin and indium oxide layer with screen. Subsequently, a dielectric layer on the phosphor layer is printed with screen. The front electrode and the phosphor layer are configured to define a light emitting graphic pattern. Then, a back electrode is stenciled onto the dielectric layer to form an EL lamp. As a result, the plastic sign contains an EL lamp without requiring the coupling of a prefabricated EL lamp to the sign. More specifically, and with reference, now, to Figure 7, there is first placed a sign of substantially transparent heat stabilized polycarbonate 140 (for example, a sign having a plastic substrate)., with a front surface 142A and a back surface 142B), in an automatic flat screen printing press (not shown in Figure 7). A bottom substrate 144 is printed on the back surface 142B, said substrate substantially covering the entire back surface 142B, except for an illumination zone 146 thereof. The illumination area 146 is configured as an inverted image (for example, as the inverted image of an "R") of the image to be illuminated (for example, an "R"). Next, a dielectric background layer 148 is printed on the back surface of the sign 142B and the background substrate 144. The dielectric background layer 148 covers substantially all of the background substrate 144 and contains an illumination portion 150 that is substantially aligned with the illumination zone 146.

Then, a front electrode 152 made of silver ink is printed on the back surface of the sign 142B, so that the front electrode 152 makes contact with the outer perimeter of the illumination part 150. In addition a connection 154 of the front electrode 152 extends from the perimeter of the illumination portion 150 to the perimeter 156 of the signage 140. The front electrode 152 then hardens for approximately two minutes at about 176.6 ° C. Subsequently, a layer of tin oxide and indium 158 is printed with stencil on the back surface of the sign 142B. The tin and indium oxide layer 158 has the same size and shape as the illumination zone 146 and is printed with screen in the form of an inverted image (for example, in the form of an inverted image of an "R") over the area of illumination 146 of the rear surface of the 142B sign. The layer of tin oxide and indium 158 hardens, then, for example, for about two minutes at about 176.6 ° C. After the tin oxide and indium oxide layer 158 is printed on the surface of the sign 142B, a phosphor layer 160 is printed on the tin and indium oxide layer 158. The phosphor layer 160 is printed with stencil in the form of an inverted image and has substantially the same shape and size as the tin oxide and indium oxide layer 158. The phosphor layer 160 can be printed on the sign 140 with, for example, the same stencil used to print the oxide layer. tin and indium 158. The phosphor layer 160 hardens, then, for approximately two minutes, for example, at about 176.6 ° C. Next, a dielectric layer 162 is printed on the surface of the sign 142B, so that the dielectric layer 162 covers substantially all of the phosphor layer 160 and the front electrode 152. In particular, and as explained above With regard to the dielectric layers 94 and 62, the dielectric layer 162 comprises two layers (not shown) of material of high dielectric constant, such as, for example, barium titanate dispersed in polymeric binder. The first barium titanate layer is printed with screen on a phosphor layer 160, and then hardened to dry for approximately two minutes at a temperature of about 176.6 ° C. The second barium titanate layer is then printed with screen on the first layer of barium titanate and hardened to dry for about two minutes at a temperature of about 176.6 ° C to form the dielectric layer 162 According to one embodiment, the dielectric layer 162 has substantially the same shape as the illumination area 146, but is approximately 2% larger than said area 146 and its size is such that it covers at least a portion of the frontal electrode connection 154. A back electrode 164 is printed on the back surface 142B, on the dielectric layer 162, said back electrode comprising a lighting portion 166 and a back electrode connection 168. The illumination portion 166 is substantially the same size and Thus, the illumination area 146, and the rear electrode 168 extends from the illumination part 166 to the perimeter of the sign 156. The posterior electrode 1 64 can be made, for example, of carbon capable of printing with screen printing. The back electrode 164, the dielectric layer 162, the phosphor layer 160, the tin and indium oxide layer 158, and the front electrode 152 form an EL lamp extending from the rear surface 142B of the sign 140. Subsequently, the Stencilled a transparent UV coating (not shown in Figure 7) on the back surface 142B, said coating covering the back electrode 164, the dielectric layer 162, the phosphor layer 160, the tin oxide and indium layer 158, the front electrode 152, the dielectric bottom layer 148 and the bottom layer 144. In particular, the transparent UV coating substantially covers the entire back surface 142B, except for a terminal part 170, through which a part of the connection of the front electrode 154 and the connection of the back electrode 168 to facilitate the coupling of a power supply source (not shown in Figure 7) to said connections 154 and 168. The sign can then be hung up, for example, of a window, of a wall, or suspended from the ceiling, so that the illumination zone 146 is a positive image (eg, an "R") when viewed from a location adjacent to the front surface 142A of the sign 140.

The method described above provides an illuminated plastic sign having an EL lamp, but which does not require coupling a prefabricated EL lamp to the sign. In addition, the sign THE plane 140 can be vacuum molded to give it a substantially three-dimensional shape. For example, the sign 140 can be placed on top of a mandrel mold and then vacuum molded according to known vacuum molding techniques. The foregoing discussion specifically relates to methods for providing illuminated signs having at least one EL lamp. However, it should be understood that such methods can be used to provide products other than luminous signs. For example, said methods can be used to manufacture luminous microstructures for cycling or motorcycling helmets and three-dimensional signs. From the above description of the present invention it is evident that the objects thereof are achieved. Although the invention has been described and illustrated in detail, it should be clearly understood that it is offered only by way of illustration and example, and should not be considered limiting. For example, although the above-described signs contain only one or two EL lamps, said signs may contain more than two (e.g., three, four, five, or even more) EL lamps. Furthermore, although the methods have been described in connection with the manufacture of signs having EL lamps, these methods can also be used to manufacture other products having EL lamps. Accordingly, the spirit and scope of the invention are limited only by the terms of the appended claims.

Claims (29)

NOVELTY OF THE INVENTION CLAIMS

1. - The sign comprising a surface and an illuminated graphic pattern coupled thereto, characterized in that said illuminated graphic pattern includes: a first electrode formed on said surface of the sign; a phosphor layer substantially aligned with said first electrode and printed with stencil on said sign surface; a layer of tin oxide and indium substantially aligned with said phosphor layer and printed with stencil on said phosphor layer; and a second electrode printed with stencil on said surface of the sign and configured to transport energy to said layer of tin oxide and indium.

2. The sign according to claim 1, further characterized in that said first electrode comprises a posterior electrode, and because said posterior electrode is printed on said substrate in the form of a direct image.

3. The sign according to claim 1, further characterized in that it also comprises a dielectric layer between said first electrode and said phosphor layer.

4. The method for forming a graphic pattern illuminated on a substrate, said method comprising the steps of: forming a subsequent electrode on the substrate; forming at least one dielectric layer on the posterior electrode; forming a phosphor layer on the dielectric layer; forming an ink layer of tin oxide and indium on the phosphor layer; and forming a front electrode on the dielectric layer to transport energy to the tin and indium oxide layer.

5. The method according to claim 4, further characterized in that the formation of the posterior electrode on the substrate comprises the step of printing with stencil the posterior electrode on the substrate.

6. The method according to claim 4, further characterized in that the substrate is a sign having a front surface, and by comprising the formation of the back electrode on the substrate the step of printing with screen the rear electrode on the front surface of the sign.

7. The method according to claim 4, characterized by comprising the formation of at least one dielectric layer on the back electrode the step of printing with screen the dielectric layer on the back electrode.

8. The method according to claim 4, further characterized in that the formation of a phosphor layer comprises the step of printing with screen the phosphor layer in the form of direct image that has substantially the same shape and size as the graphic pattern illuminated.

9. - The method according to claim 4, further characterized in that the formation of a layer of tin oxide and indium on the phosphor layer comprises the step of printing with tin screen tin oxide and indium on the phosphorus layer in the form of direct image that has substantially the same shape and size as the illuminated graphic pattern.

10. The method according to claim 4, further comprising also comprising the step of forming an ultraviolet coating on the substrate, so that the ultraviolet coating substantially covers the layer of tin oxide and indium and the front electrode .

11. The method according to claim 4, further characterized by also comprising the step of forming an ultraviolet coating on the substrate before forming the subsequent electrode on the substrate.

12. The method according to claim 4, further characterized by comprising, also, the step of printing with stencil a background on the substrate.

13. The method according to claim 4, further characterized by being the metal substrate.

14. The method according to claim 4, further characterized by being the plastic substrate.

15. - The method according to claim 4, further characterized by being the cardboard substrate.

16. The method according to claim 4, further characterized by defining the phosphor layer at least two illumination parts.

17. The method for an electroluminescent lamp and an integrated advertising sign, the advertising sign comprising a surface, further characterized by comprising the steps of: forming a first electrode on the surface of the sign; form a layer of tin oxide and indium on the surface of the sign; Stenciling a layer of phosphorus over the layer of tin oxide and indium; stenciling a dielectric layer on the surface of the sign; and forming a second electrode on the surface of the sign, on the dielectric layer.

18. The method according to claim 17, further characterized in that the placard is made of substantially transparent plastic and comprises a back surface, and by comprising the formation of a first electrode on the surface of the sign the step of printing with stencil a front electrode on the rear surface of the sign.

19. The method according to claim 18, further characterized by including the sign, also an area of illumination, said method also comprising the step of printing with screen a dielectric background layer on the surface of the sign, comprising The dielectric background layer is a part of illumination that is substantially aligned with the illumination zone.

20. The method according to claim 19, further characterized by comprising said step of forming a first electrode the step of printing with stencil a first electrode on the surface of the sign so that the first electrode makes contact with the outer perimeter of the part of lighting.

21. The method according to claim 17, further characterized by comprising said step of forming a layer of tin oxide and indium the step of printing with stencil a layer of tin oxide and indium on the surface of the sign.

22. The method according to claim 17, further characterized by comprising said step of forming a second electrode on the surface of the sign the step of printing with screen a subsequent electrode on the dielectric layer.

23. The method according to claim 17, further characterized by comprising the step of printing with stencil a UV coating on the rear surface of the sign, on the first electrode, the layer of tin oxide and indium, the phosphor layer, the dielectric layer, and the second electrode layer.

24. The method according to claim 17, further characterized by comprising, also, an initial step of printing a substrate substrate on the surface of the sign.

25. - The sign comprising a surface and a graphic pattern coupled thereto, further characterized by comprising said illuminated design: a first electrode formed on said surface of the sign; a layer of tin oxide and indium printed with stencil on said surface of the sign; a phosphor layer printed with stencil on said layer of tin and indium oxide; a dielectric layer printed with stencil on said surface of the sign; and a second electrode formed on the surface of the sign, on the dielectric layer.

26. The sign according to claim 25, further characterized in that said first electrode comprises a front electrode, and said front electrode is printed on said substrate in the form of an inverted image.

27. The sign according to claim 25, further characterized in that said second electrode is a back electrode, and said back electrode is printed with said electrode on said dielectric layer in the form of an inverted image.

28. The sign according to claim 1, further characterized in that said second electrode is a front electrode, and said front electrode is printed with stencil on said surface of the sign in the form of a direct image.

29. The sign according to claim 1, further characterized by including the second electrode a first part, and printed said second electrode on said surface of the sign so that said first part of said second electrode makes contact with the perimeter outside of said layer of tin oxide and indium.