This application claims the benefit of U.S. Provisional application Ser. No. 60/142,019, filed Jul. 7, 1999.

This application claims the benefit of (a) provisional application Ser. No. 60/142,019, filed Jul. 7, 1999 and (b) Ser. No. 09/158,290, filed Sep. 22, 1998 (now U.S. Pat. No. 6,214,155 ), which is a continuation of Ser. No. 08/727,789 (now U.S. Pat. No. 5,817,207 ), which claims the benefit of provisional application Ser. No. 60/005,685. filed on Oct. 17, 1995.

The present invention relates generally to an ultra-thin flexible durable identification device and the manufacture thereof, and more particularly to radio frequency identification (RFID) devices and the manufacture of RFID devices that can be made in many shapes and sizes and that have superior outer surface matte or glossy such that device may receive dye sublimation printing or the like.

Identification devices such as cards, badges, tags labels and bracelets have been used for years for all kinds of identification, such as passports, luggage, all kinds of tickets, hospital/pharmacy medical records and access passes, all of which have not been totally free from theft and counterfeit resulting in the loss of thousands of dollars. With the rapid progress in new technology the problems associated with the use of such identification devices are being replaced with a more secure identification device having a RFID smart chip that gives more information such as biometrics and read write technology. Thus this more secure plastic device is very difficult or impossible to fraudulently manipulate.

The present invention is therefore directed to a ultra-thin flexible durable plastic device made in all shapes and sizes having at least one electronic element embedded therein and to a hot or cold lamination method for the manufacture of plastic devices including at least one electronic element therein. The device can be used as cards, tags, badges, bracelets and labels. The device is durable and flexible and it can be used as a sticker when adhesive is applied because it is ultra-thin. The device has an overall thickness in the range of 0.005 inches to 0.033 inches and comprises a plastic or other substrate core having at least one electronic element embedded therein with at least one of the upper and lower surfaces of the core comprising a coating printed or otherwise applied thereon. An overlaminate film is preferably provided over the coated surface of the core and the resulting device has a variation in thickness across the surfaces thereof of no greater than approximately 0.0005 inches. The hot or cold lamination method of the present invention comprises the steps of providing first and second plastic or other substrate core sheets, positioning at least one electronic element between the first and second core sheets to thus form a core and placing the core in a laminator and closing the lamination without applying laminator ram pressure to the core. A heat cycle is applied to the core sheets in the laminator thus liquefying or partially liquefying the sheets. The laminator ram pressure is then increased in combination with the heat. A cooling cycle is then applied to the core in the laminator preferably with an associated increase in ram pressure, and the core is removed from the laminator. The sheets are then cut separating the individual device from the core sheet and this results in a plastic device having a thickness in the range of approximately 0.005 inches-0.033 inches with a surface glossy or matte dependent on customer's request. The invention is also directed to a device manufactured in accordance with the above process which results in a plastic device having a thickness in the range of approximately 0.005 inches-0.033 inches with a surface smoothness of at least approximately 0.0005 inches. The present invention provides numerous advantages over known plastic devices and known plastic device with electronic elements such as a computer chip embedded therein with a pleasing aesthetic appearance and able to withstand various harsh chemicals and pressures.

The present invention relates to a ultra-thin flexible durable plastic device including at least one electronic element embedded therein. The present invention also relates to a hot lamination process for the manufacture of plastic devices and more particularly to a hot or cold lamination process for the manufacture of plastic devices that include an electronic element such as a computer chip or other electronic element embedded therein. The electronic element may preform a wide variety of functions and take a wide variety of forms. Such devices without regard to the particular electronic element embedded therein, will hereinafter be referred to as radio frequency identification (RFID) devices. The present invention also relates to a ultra-thin durable plastic or other composition device in all shapes and sizes that can withstand harsh chemicals and various pressures that could be used in the are-o-space industry.

Referring now to FIG. 1 there can be seen a plastic RFID device 10 manufactured in accordance with the present invention and including an electronic element 20 embedded therein. Device 10 includes an upper surface 12 and a lower surface 14. Electronic element 20 may take a wide variety of forms and perform a wide variety of functions. As shown in FIGS. 3A-3D respectively, electronic element 20,20′,20″, 20′″ may be provided by a micro-chip 22 including a wire antenna 24, connected thereto, a micro-chip 22′ and a circuit board antenna 24′, a read/write micro-chip 22″ and a wire coil antenna 24″, a printed screen or litho conductive metallic or carbon ink antenna 24′″ or any other suitable electronic element. These electronic elements 20, 20′, 20″ and 20′″ and their insertion into plastic or other substrate devices is not new, however, the present invention provides a new hot or cold lamination process for manufacturing plastic devices 10 with these electronic elements 20, 20′, 20″ and 20′″ embedded therein such that the devices 10 are aestically pleasing meeting customers specifications and demands in such that at least one of the upper and lower surfaces 12, 14 of device 10 is sufficiently smooth and is otherwise capable of of receiving dye sublimation printing or thermo printing. Specifically a device in accordance with the present invention has a thickness of approximately in the range of 0.005 inches to 0.033 inches with a surface smoothness of 0.0005 inches. This surface may also have a matte finish on one or more sides.

As shown in FIGS. 4-10 one or more devices 10 in accordance with the present invention may be manufactured by positioning an electronic element 20 between first and second sheets of core 30, 32 to form a core 33. Preferably is shown in FIGS. 5-10 a plurality of devices are manufactured simultaneously, in thus, a plurality of electronic elements 20 are positioned between the first and second sheets of plastic core stock 30, 32 (only the second sheet 32 being shown in FIG. 5 for clarity). When a plurality of electronic elements 20 are positioned between first and second sheets plastic or other substrates core stock 30, 32 electronic elements 20 are properly positioned relative to one another such that a plurality devices may be out from the resulting core stock. Plastic core sheets 30-32 may be provided by a wide variety of plastics or other substrates, the preferred being polyvinyl chloride (PVC) having a thickness in the range of 0.005 inches to 0.0225 inches. Those skilled in the art will recognize that the thickness of the plastic core sheets will depend upon the thickness of the one or more electronic elements that are to be embedded therebetween. Other suitable plastic that may be utilized include polyester, acrylonitrile-butadiene-styrene (ABS), PET or composition of many.

Subsequent to placing one or more electronic elements 20 between the first and second sheets 30, 32 of plastic or other substrate core stock to form core 33, this core 33 is placed in a laminator apparatus 40 of the type well known in the art of plastic device manufacturing. As is shown in FIG. 7, laminator 40 includes upper and lower platens 42, 44 for applying ram pressure to an article positioned therebetween. In addition to the ability to apply ram pressure, laminator 40 is preferably of the type having controlled platens 42, 44 that provide both heat and chill cycles and preferably includes cycle timer to regulate cycle time. (Other laminators of different designs may be used also that have a single ram for the hot platens and a single ram for the cold platens, known as a dual stack laminator, or roll laminators with hot rollers and chill rollers.) Core 33 is positioned between first and second laminating plates 50, 52, one of which is preferably matte finished to provide laminated core 33 with at least one textured outer surface. First and second laminating pads 60, 62 are positioned outside of the laminating plates 50, 52 and first and second steel plates 70, 72 are likewise positioned outside of pads of 60, 62 and the entire assembly forms a book 37 for being positioned in laminator 40 between plates 42, 44.

Once book 37 is positioned in laminator 40 as shown in FIG. 7, the first lamination cycle is initiated by closing laminator platens 42, 44, preferably applying little or no ram pressure to book 37. A laminator heat cycle is initiated bringing the temperature of platens 42, 44 up to range of 275° F. to 400° F. and most preferably up to a range of 300° F. to 370° F. for a period of greater than 5 minutes and preferably in the range of 7 to 10 minutes. Once the heat cycle has been applied to the book 37 as is set forth above, the ram pressure of laminator 40 is increased to facilitate the flow of the plastic core sheets 30, 32 so that the one or more electronic elements 20 are encapsulated thereby, and so that sheets 30, 32 form a uniform core 33 (seen most clearly in FIGS. 8-10 with upper and lower surfaces 34, 35. As mentioned, the use of matte finished laminator plates 50, 52 provides surfaces 34, 35 with a slightly roughened or textured quality which will facilitate the application of a coating thereto as is discussed below. The ram pressure applied during the heat cycle and the length of the heat cycle may vary, depending especially upon the size of sheets 30, 32. For example, the cycle time may be in the range of 10-15 minutes. In one example, a ram pressure of 940.135 pounds per square inch (p.s.i.) was applied for 10-15 minutes to form a uniform core 33, using sheets 30, 32, of a size in the range of 12 inches by 24 inches to 24 inches by 36 inches.

Subsequent to the above heat cycle, laminator 40 applies a chill cycle to book 37 during which time and ram pressure of the laminator 40 is increased, preferably by approximately 25%, until the platens 42, 44 have been cooled in approximately 40° F. to 65° F. for approximately 10-15 minutes. Core 33 may then be removed from laminator 40 for additional processing. If a single lamination step is used, a glossy plate might be used at this point of lamination to provide a mirror finish on the device. At this point the sheets will be ready for cutting out the devices separating the plurality of devices from the sheets.

Subsequent to the removal of core 30 from laminator 40 and as illustrated in FIG. 8 core 33 is coated on at least one of its upper and lower surfaces 34, 35 with a layer of printing ink 36. This may be accomplished using a wide variety of printing techniques such as offset printing, letter-press printing, screen printing, roller coating, spray printing, litho-printing and other suitable printing techniques. As shown in FIG. 8 core 33, is fed in the direction indicated with arrow A through a printing press, a lithographic printer or a similar apparatus 80. This printing step is performed to coat at least one surface 34, 35 of core 33 with a layer of aesthetically pleasing ink 36. This layer of ink 36 cosmetically hides the one or more electronic elements 20 that are embedded within core 33 and prevents these one or more electronic elements 20 from showing through the relatively thin core 33. In this manner, the one or more electronic elements 20 encapsulated in core 33 are completely hidden from view without requiring the plastic used in the manufacture core 33 to be excessively thick.

Referring now to FIGS. 9-10, the final processing of core 33 which now comprises a layer of ink 36 or the like on at least one surface 34, 35 thereof, is schematically illustrated. A layer of overlaminate film such as clear overlaminate film 38,39 is positioned on at least one ink coated surface 34,35 of core 33, and preferably core 33 is positioned between two similar sheets of overlaminate film 38,39 as shown. Overlaminate film is very thin, for example in the range of 0.0015 inches thick. A book 135 is then constructed for insertion into laminator 40 as is schematically illustrated FIG. 10. Book 135 comprising core 33, including at least one layer of ink 36 and at least one layer of overlamination film 38,39 is positioned between laminating plates which are preferably highly polished plates such as mirror finished stainless steel plates 90, 92. Book 135 also comprises first and second laminating pads 60, 62 and first and second steel plates 70, 72 as is discussed above in relation to FIG. 7.

When book 135 is positioned between upper and lower platens 42, 44 of laminator 40 as shown in FIG. 10, the laminator is closed and a heat cycle in the range of 175° F. to 300° F. and most preferably in the range of 180° F. to 275° F. is applied to book 135 for a period of 10 to 25 minutes with a ram pressure that varies depending upon sheet size or the ram size of the laminator 40, but which is typically approximately 1000 p.s.i. with an 18 inch diameter ram. The laminator 40 is then caused to execute a chill cycle, preferably with a corresponding increase in ram pressure. For example, the chill temperature may be in the range of 40° F. to 65° F. and last for a period of 10 to 25 minutes. A ram pressure increase of approximately 25% over the pressure used for the heat cycle has been found to be most preferable.

Subsequent to the above described second lamination cycle as illustrated in FIG. 10, a sheet of plastic or other substrate core stock is provided which comprises at least core 33 with at least one surface 34,35 thereof covered by a layer of ink 36 and with at least one surface 34, 35 thereof covered by a layer of overlaminate film 36, 39.

Preferably plastic device stock manufactured in accordance with the present invention comprises core 33 covered on both surfaces 34, 35 with a layer of ink 36 which is positioned between layers of overlaminate film 38, 39 all of which has been laminated together as described. One or more devices 10 then may be cut from the resulting plastic core stock and device 10 will have a thickness of in the range of 0.005 inches to 0.033 inches with variation in overall thickness across the surfaces 12,14 thereof being no greater than approximately 0.0005 inches. The one or more devices 10 can thus be said to have a surface smoothness of approximately 0.0005 inches or better. Thus, a device 10 manufactured in accordance with the present invention includes at least one surface 12, 14 at preferably both surfaces 12, 14 that are sufficiently smooth and regular to receive dye sublimation printing.

Those skilled in the art will recognize that the forgoing descriptions has set forth the preferred embodiment of the invention in particular detail and it must be understood that numerous modifications, substitutions and changes may be undertaken without departing from the true spirit and scope of the present invention as defined by the ensuring claims.