RFID-Transponder with printable surface

p0001The invention is directed to directly printable and / or writable RFID transponders, which are useful as labels, Transportgutanhänger, identification cards, access authorization cards.

p0002It is known to use labels as remotely readable identification tags for baggage. These have, for example, a flexible substrate, a formed on said substrate antenna having a transponder circuit chip, as well as adhesive layers for bonding chip and the antenna in the antenna pads and the chip connection points, as well as between the transponder, the substrate and a protective film. Such a label is in<patcit id="pcit0001" dnum="EP595549A"><text>EP-A-595 549</text></patcit> disclosed.

p0003Out <patcit id="pcit0002" dnum="EP704816A"><text>EP-A-704 816</text></patcit> is a known RFID transponder, with resonant antenna and electrically bandaged circuit chip which are disposed on one side of a flexible dielectric carrier, for example of paper or plastic. The transponder is provided on the side opposite the antenna surface of the support with an adhesive layer to facilitate attachment to objects to be identified. The adhesive layer is covered with a removable protective layer.

p0004Out <patcit id="pcit0003" dnum="DE3807936A"><text>DE-A-38 07 936</text></patcit> is an electronic anti-theft system is known having a transmission frequency in the GHz range- (approx. 2.5 GHz) arbettet to enable small dimensions of the passive locking element (passive transponder). The passive safety element is connected to the product label as a unit. This made<patcit id="pcit0004" dnum="DE3807936A"><text>DE-A-38 07 936</text></patcit> known system uses an in <patcit id="pcit0005" dnum="DE4002738A"><text>DE-A-40 02 738</text></patcit> described stationary device for registration and identification of floating passive radio recording chips, which enable targeted einzuspeichern information in an addressed passive radio recording chip and there retrieve stored information at any time. It is described to mount the passive registration chips to letters, parcels, packages or luggage.

p0005<patcit id="pcit0006" dnum="US5294290A"><text>US-A-5,294,290</text></patcit> depends on the mass production of flexible flat resonant sound loops that are formed on a polymer film as a carrier. The multilayer laminate has portions which can be printed with optically readable information. The multilayer laminate also has a release paper covered with pressure-sensitive adhesive layer.

p0006In the known labels or cards with RFID transponders, which have a carrier film having disposed thereon antenna and circuit chip, the so-called foil transponder between a label face paper or a plastic film and other layers are laminated to protect the chip and antenna against damage. Similar laminate structures are also known for tickets, tickets, hang tags with RFID transponders. These laminates can be printed on the front and optionally also on the back with customary procedures.

p0007The object of the invention is to provide labels, Transportgutanhänger, identification cards, access authorization cards and the like, each having an RFID transponder with antenna and related circuitry chip to simplify the structure so that a lower-cost mass production is possible.

p0008This object is solved by RFID transponder with a printable surface, having a polymer film as a carrier for at least one antenna and a covered with a protective layer as the top layer adhesive layer, characterized in that the printable surface as a particulate on a surface of the polymer film pigment and binder-containing layer is formed, which is arranged with a protective layer as cover layer covered adhesive layer on the side opposite the printable surface surface of the polymer film, the RFID transponders each comprising at least an antenna and electrically connected thereto, mounted on the polymer film circuit chip, the antenna and the circuit chip are arranged on the same side of the polymer film and the printable surface is angeornet on the surface of polymer film, on which no circuit chip is located ..

p0009Suitable as a carrier polymer films may, for example, polyester films. be polyvinyl chloride, polyolefin (polypropylene, polyethylene), polycarbonate films, polystyrene films, polyamide films, or cellulose acetate. The carrier films preferably have a thickness of 30 .mu.m to 820 .mu.m, particularly preferably from 36 to to 100 microns. The carrier films may be transparent or opaque, and optionally have a microporous structure.

p0010The carrier films may be formed by itself already printable and / or writable. For the formation of flat, in particular rectangular RFID transponders on a carrier film one made of plastic or both sides of an antenna having one or more windings of an electrically conductive material is applied. The antenna is formed by conventional means on the dielectric polymer carrier film. The antenna comprises antenna connection points, which are preferably arranged on the support sheet so that they are bounded by the antenna coil. The Antennenwindung (s) has / have a thickness of 10 microns to 50 microns.

p0011Which is also mounted on the carrier film circuit chip having first and second electrical chip contact points against an inner surface portion of the chip, and the electrical connection of the chip with the antenna is preferably made by means of electrically conductive adhesive which is disposed between the antenna pads and the chip sites. Chip antenna and on the same side of the polymer film disposed. This is especially preferred if one of a direct printable formed polymer film is used as the carrier film.

p0012The invention printable and / or writable layer is disposed on the surface of the polymer film, on which no chip is located. The printable / writable layer can be opaque but also semitransparent.

p0013The printable layer contains finely divided pigments such as inorganic pigments or fillers such as kaolin, calcium carbonate, silica and silicates, alumina, aluminum hydroxide, zinc oxide, barium sulfate, talc, or mixtures thereof. However, it is also known for paper coatings organic polymer pigments, are optionally used in combination with inorganic pigments, for the printable layer.

p0014Suitable film-forming binders for forming the layer and fixing the pigments to the support film are, for example, polyvinyl alcohol, polyvinylpyrrolidone, casein, starch, starch derivatives, styrene-maleic anhydride copolymers, as well-known for paper coatings conventional polymer latexes such as styrene-butadiene, styrene-acrylic acid copolymers, acrylic latexes. It can also generally mixtures of soluble binders are another or latices with soluble binders or mixtures of latexes. It is also solvent-based coating compositions are used for example with nitrocellulose as the binder for forming the printable layer.

p0015The ratio of pigment and binder is selected so that sufficient adhesion of the printable layer is ensured on the polymer film, however, the layer still has sufficient porosity so as to be readily printable. Typically ranging from 5 to 30 parts by weight, preferably 20 parts by weight to Binder per 100 parts by weight Pigment made to form a sufficiently firm printable and / or writable layer.

p0016The printable layer may contain conventional adjuvants such as dispersants. Defoamers, crosslinking agents, adhesion promoters, thickeners, dyes, UV stabilizers.

p0017The printable layer preferably has a coat weight (dry) of 5 g / m² to 30 g / m², Preferably 7 g / m² to 20 g / m² on.

p0018In one embodiment of the invention, between the support film and the printable layer is an intermediate layer can be arranged, which also contains particulate pigments / fillers and binders. The intermediate layer increases the opacity of the total layer on that side of the carrier film and may also have insulating effect to heat or barrier properties for migrating components. Basically the same film-forming binders and pigments can be used for the printable layer for the intermediate layer. The intermediate layer preferably has a coat weight (dry) of 1 g / m² to 10 g / m², In order to improve the adhesion of the intermediate layer on the polymer film, the intermediate layer may also contain an adhesion promoter in addition to the usual auxiliaries and additives, or the polymer film itself can have an adhesion-promoting surface equipment.

p0019In one embodiment of the invention, the printable layer is designed as a heat-sensitive recording layer. In this embodiment, the printable layer additionally contains dye precursor compound (s) which forms a color upon application of heat with a suitable acidic compound as a reaction partner (form) and one or more fusible links, such as waxes and conventional excipients. The fusible links are to support the action of heat contact of the color-forming reactants. In another embodiment of the invention, the printable layer is designed as a ink-receptive recording layer for printing by means of ink jet method. In this embodiment, the printable layer may in addition to the pigment (s) and binder (s) preferably contain one or more cationic compounds for the fixation of the dyes of the aqueous / alcoholic inks. For example, cationic acrylates, acrylamides, polydiallyl dimethyl amine chloride, polyallylamines, polydiallylamines, polyimides, quaternary ammonium compounds and customary in such recording layers further auxiliaries.

p0020The printable layer is printable by other, in direct requirement (on-demand) executable printing methods such as thermal transfer printing, laser printing, magnetography, dot matrix due to the presence of finely divided pigments and binder (s) generally. The printable layer is also using flexo, offset, gravure, and screen printing can be printed.

p0021The particular advantage of the invention directly printable RFID transponders is that they can be printed with commercially introduced printers when needed immediately to form on the surface of optically readable information corresponding to the intended application as a label, pendants, access authorization card, identification card. In parallel, the same information and / or additional information in the circuit chip can be stored in retrievable form again.

p0022On the opposite surface of the printable layer, the carrier film to an adhesive layer. The adhesive layer may have a basis weight of 3 g / m² to 30 g / m², Preferably from 5 g / m² to 15 g / m² have.

p0023The adhesive layer can be formed from commercially available hot-melt adhesives or conventional laminating adhesives, in particular if the top layer is to be permanently attached to the carrier film. In this embodiment of the invention is used as the top layer of paper or cardboard or plastic film, in order to use the printable RFID transponders directly as identification cards, access authorization cards or pendants can. The basis weight of the paper / cardboard for the top layer is selected according to the desired rigidity for the intended use of the map. It can range from 50 g / m² to 250 g / m², Preferably 70 g / m² to 120 g / m² be.

p0024In another embodiment of the invention, a pressure sensitive adhesive is used to form the adhesive layer. Suitable pressure-sensitive adhesive for forming a pressure sensitive adhesive layer are, for example, pressure-sensitive adhesive, aqueous dispersions based on acrylic acid, acrylate (ester with C₄ -C_8thAlcohols) and / or acrylate (ester with C₄ -C_8thAlcohols) and their copolymers with vinyl acetate, acrylonitrile, Diactetonacrylamid and / or cross-linked comonomers (eg divinylbenzene or ethylene dimethacrylate with and without modifying resin dispersions (hydrocarbon resins, alkylphenol resins, terpene-phenolic resins, beta-pinene, rosins, methylstyrene Vinyltoluolharze). Acrylate adhesive. Dissolved in organic solvents with eg Kollophoniumtriglycerid- or hydrogenated rosins as tackifier component by copolymerization with bifunctional monomers such as divinylbenzene or ethylene dimethacrylate or copolymerization with UV photoinitiators (eg benzophenone) derivatized acrylates, radiation-melt pressure sensitive adhesive based on acrylate hotmelt PSAs based on isobutylene-isoprene, isobutylene-butadiene or ethylene-butadiene block copolymers or styrene (SIS-SB, SBS and SE / BS copolymers) with the addition of tackifier resins, eg aliphatic olefin, Kollophonium- or terpene-phenolic resins or polyaromatic. in gasoline dissolved adhesives based on natural rubber with Cummaron-indene, Kollophonium- or hydrocarbon resins (for example polyterpenes or poly-beta-pinene) as tackifiers.

p0025The adhesive layer is covered with a re-release liner in order to use the printable RFID transponders directly as self-adhesive labels for labeling of transported goods, textiles or containers after removing the top layer can. Such detachable cover layers to protect the adhesive layer until its final use, may be so-called release papers, which are papers which have at least a thus finished surface, so that upon contact with the pressure-sensitive adhesive, a connection is formed which, however, without adversely affecting the adhesive effect of the adhesive layer again is releasable.

p0026Suitable release papers are those having a surface layer on the front, which can contain as a release agent: acrylates polymers based on cellulose acetate, (meth) acrylonitrile, vinyl chloride, vinyl ethers, or copolymers thereof with, for example, maleic anhydride, or modified with aldehyde or Iminharzen; Waxes based on polyethylene or polyamides or mixtures with polymers on the basis of nitrocellulose, polystyrene, or vinyl chloride-vinyl acetate copolymers thereof; Polyvinyl alcohols with long-chain; Chromstearaten and based on derivatives; crosslinked polyorganosiloxanes, optionally in admixture with vinyl ethers and / or maleic anhydride polymers. Silicone-containing separating layers are applied from solutions in organic solvents or from aqueous emulsion or as a liquid polyorganosiloxanes on a suitable carrier material and subsequently cross-linked. The crosslinking can be effected by catalyzed condensation, addition reaction, such as hydrosilylation or by means of UV or EB radiation.

p0027The printable layer, optionally the intermediate layer and the adhesive layer may be applied to the backing film by conventional methods known for this purpose. In the case of pressure-sensitive adhesive layers, especially if they are to be applied from organic solvents, it is preferable to form adhesive layer provided on the with release effect. (Abhäsiveigenschaft) layer and then to bring the polymer carrier film with trained RFID transponders in contact with the adhesive layer ,

p0028In one embodiment of the invention an endless polymeric film tape is used as a carrier for the formation of the RFID transponder. On the tape, a plurality of RFID transponders each with antenna and chip are formed in the strip running direction. It is also possible to use a wider film strip and provided in the strip running direction in parallel and closely spaced rows with a plurality of RFID transponders. Adhesive layer and covering layer are preferably attached continuously on one of the surfaces of the polymer film strip in these embodiments. the RFID transponders are preferably formed in the strip running direction at a distance from each other.

p0029The printable layer on the opposite surface of the carrier film may also be formed continuously. However, it is also possible for the printable layer respectively applied only in the region of the RFID transponder and to leave the parts of the strip between the in tape running direction in spaced RFID transponders and optionally present rows of RFID transponders free of the printable layer.

p0030These, respectively interrupted between the RFID transponders forming the printable layer has the advantage that detect when printing the film sensors of the beginning and end of the respective RFID transponder in the band and the printing of the RFID transponder can control accurate register. In one embodiment of an endless RFID transponder tape, it is preferable transversely to the direction of belt travel to form between the RFID transponders at least one prepared parting line as a predetermined breaking point in order to facilitate the removal of the unprinted or printed RFID transponders from the tape.

p0031Such intended separation points between the printable RFID transponders of the strip can be designed differently. For example, can be present, which make the intended separation points visible and facilitate separation of individual units between adjacent RFID transponders transversely to the strip running direction perforations in the foil strip. As already described, the individual RFID tags on the carrier film are preferably not directly adjacent to one another are formed, but isolated, so that adjacent RFID transponder having on the carrier foil in the band running direction a distance from one another. To assist in severing the carrier film to such a predetermined separation points, the top layer may additionally be perforated and / or punched holes. Such a design of predetermined separation points is especially preferred when the film strip having Angreifstellen for belt conveying elements, and / or if the film strip is to be processed for stacking with a zig-zag folding. However, such perforations also have advantages if the film strip is to be processed into rolls.

p0032In the embodiments of the printable RFID transponders in band form with a series of a plurality of RFID transponders, the bandwidth of 45 mm can be up to 100 mm. In the case of narrower webs, the rectangular RFID transponders are formed in the longitudinal direction of the tape. Wider webs are then required when the rectangular RFID transponders are formed transversely to the strip running direction.

p0033Bandwidth is the commercial printers that perform printing labels or access authorization cards as needed directly adapted.

example 1

p0034It is a film transponder band consisting of a transparent 48 mm wide and 36 micron thick PETP film and applied to both sides antenna structures made of aluminum, which are in electrical communication with a disposed on the polymeric film circuit chip used, which embodiment is not claimed herein. The foil strip is processed in a gear machine of the roller and a containing means of a first engraved roll to form a heat-insulating intermediate layer, a coating composition, the organic hollow pigments and conventional film-forming binder and auxiliary materials, applied as an aqueous dispersion. After drying with the aid of IR radiators is a coating composition with a second engraved roll applied and formed a heat-sensitive layer, which still contains a color former and developer in addition to film-forming binders and pigment. The printable layer is accurate register applied to the intermediate layer and dried with a maximum surface temperature of 55 ° C. The coating weight (dry) of the intermediate layer is 3-5, preferably 5 g / m²; the coating weight of the heat-sensitive recording layer is 5-7, preferably 7 g / m², The coating surface is in each case 48 mm x 90 mm, and between the individual RFID transponders remains an uncoated field of 6 mm length.

p0035In a laminating a previously coated with a hot melt pressure sensitive adhesive silicone release paper as a covering layer, with a basis weight of 67 g / m² laminated. Finally, from the top, that is, the printable layer, surface respectively provided with a printable layer pre-cut down to serving as a covering layer silicone paper and there are thus formed transversely to the strip running direction preparing predetermined separating points between the individual printable RFID transponders.

p0036The strip is to roll with 200 printable RFID transponders to be used as a directly printable adhesive labels, not made up. The printable directly with commercial thermal printers RFID transponders have in training of color due to heat an impeccable contrast to, printed bar codes can be read easily. The 96 x 48 mm large pressure sensitive labels can be affixed directly as labels for cargo.

p0037In addition to the barcode each individual RFID transponders can be fitted with a wireless remote-readable information in the printing by additional devices, which in addition to the optically readable information, additional remote reading information can be stored in the label.

example 2

p0038An RFID transponder on a 48 mm wide and 96 <i>μ</i>m thick transparent PETP film and unilaterally applied antenna and chip is provided on the steel surface with a printable in ink jet process recording layer. The layer contains polyvinyl alcohol as a film-forming binder and silica as a pigment. As commissioned serves a nozzle applicator. The application weight is dry 9 g / m²,

p0039After drying and lamination of a coated with a dispersion adhesive silicone sheet on the opposite side of the label size of 85 mm x 48 mm and prepared intended separation points by cutting through the printable layer and the carrier film and the adhesive to the cover layer between the RFID transponders are D respectively transversely adapted to the strip running direction.

p0040The printable to be used as pressure sensitive labels directly by ink jet method RFID transponder can be printed in color with commercially available inkjet printers. Simultaneously or subsequently, the desired additional information can be entered in the circuit chip and retrieved at a desired later point in time of the distance.

p0041The labels used for labeling of books and to identify files and allow by retrieving the stored information non-contact control of book or file movements within guarded areas.

example 3

p0042An RFID transponder band with a structure corresponding to that of the RFID tag tape used in Example 1, having a width of 48 mm is first coated with a neutral gray colored intermediate layer on one side Next, a printable layer of pigment (s) and film-forming formed binder (s) and customary auxiliaries, which assumes conventional toner in laser printers.

p0043As application methods for the printable recording layer screen printing is used. There are printed x 96 mm accurate register each field of 48 mm. The coating weight of the intermediate layer is 6 g / m², printable toner accepting layer 5 g / m²,

p0044The single-side coated RFID transponder film strip is on the back side with a laminating adhesive and a 75 <i>μ</i>m thick opaque white PETP film as a top layer provided. The printable layer is printed partially by flexographic printing.

p0045After cutting to a size of 48 mm x 96 mm, the thus obtained on the front partially already printed RFID transponder by means of a laser printer can having an excellent quality as admission tickets at request in addition to the partial printing printed, and at the same desired far-readable information in the circuit chip get saved.

example 4

p0046The band-shaped foil RFID transponder of Example 2 is provided on the shiny side with kaolin as a pigment and polystyrene / butadiene latex containing as binders printable layer, covered on the other side with a 50 pm opaque white PETP film as cover layer by laminating adhesive , After cutting into 86 mm x 48 mm wide labels and punching the labels printable textiles hangtags can be used such as thermal transfer printing. These labels can be additionally provided to the pressure applied in the heat transfer printing optically readable information with remote-readable information in the memory chip, so that a non-contact control of the fate of the provided with such attachments label textiles in controlled areas is possible.