MXPA00005933A - Linerless postage stamps - Google Patents

Abstract

A linerless postage stamp includes a paper substrate having top and bottom faces, a pressure sensitive adhesive on the bottom face, postage stamp indicia on the top face, and release material on the top face will not adhere to the adhesive but will absorb or otherwise retain stamp cancellation ink in sufficient quantities so that a cancellation pattern thereof is clearly visible. This is typically accomplished by using a styrene acrylic latex formulation barrier coat applied to the top face in an amount between about 0.7-0.8 pounds per ream of substrate sheets, and a UV curable silicone release material applied over the barrier coat on at a weight between about 0.4-0.5 pounds per ream of substrate paper.

Description

POSTAL STAMPS WITHOUT LINING BACKGROUND AND SUMMARY OF THE INVENTION For a long time it has been considered convenient to provide postal stamps without lining, with pressure-sensitive adhesive. Postage stamps with pressure-sensitive adhesive become increasingly popular, but to date they have always required a release or detachment sheet, because if a conventional release liner is applied to the top face of the postage stamp (which is necessary to allow stacking of stamps or training in a roll configuration), the cancellation pattern applied by the Automated Postal Service Team of the USA (USP = US Postal Service), has a tendency not to adhere to the upper face of the stamp but rather to be detached during further handling, because the cancellation ink can not be absorbed by, or otherwise retained by, the Top face of the stamp. If a very light coating of release material is applied to the top of the stamp, then particularly if the stamps are not stored under ideal conditions - the adhesive of one stamp may adhere to the top face of another causing cancellation of the stamps. signs of the stamp, making it unsuitable for its intended purpose.

DE 44 11 581 Al relates to postal stamps without lining, with a paper substrate covered with an intermediate layer which is a special lacquer with great affinity for stamp colors and liquid-proof markers. The intermediate layer cooperates with an outer separation layer of release material, such that a stamp impression can not penetrate the base paper layer from the outside through the outer separation layer and the intermediate layer. The details of the intermediate lacquer layer are not described. In accordance with the present invention, the aforementioned problem is solved and it is possible to produce unlined postage stamps, which have an upper face which will properly retain the cancellation ink, when applied in a cancellation pattern such that the pattern of cancellation is visible and does not come off during normal operation. Basically, this is achieved in accordance with the present invention by providing a barrier coating on the top layer of a paper substrate. While the barrier coating seals the paper, it also creates a non-uniform surface, such that the release material can sink into the substrate as well as allow the ink of the cancellation pattern to sink into the paper. The release material must allow the ink to pass to the substrate sheet in a proportionate manner so that the adhesive on one stamp does not adhere to the top face of another. Also, the surface of the stamp should be sufficiently smooth to allow processing through conventional high-speed equipment. According to one aspect of the present invention, there is provided a method for producing a Unlined postal stamp (of a sheet or pattern having a top and bottom face) The method comprises the steps of: (a) applying a barrier that improves the absorption of the release coating or improves the porosity of the top layer of the plot or sheet; (b) apply an adhesive pressure sensitive to the bottom face; (c) applying an adhesive release material that does not adhere to the adhesive in step (b), to the barrier coating of step (a); and (d) forming the weft or sheet into separable postage stamps, with postage stamp signs in the upper face. And, wherein steps (a) and (b) are practiced to provide sufficient porosity to the top layer, so that it can absorb or otherwise retain sufficient stamp cancellation ink, such that the ink is visible on the upper face a time it is applied and dried.

Step (d) by (di) applying postal stamp signals to the upper face before performing step (a) and (d2) forming lines of weakness in the sheet Q frame to define the boundaries of individual separable stamps. Step (d2) is typically practiced before steps (b) and (c), but may be practiced at any stage in the method including after all stages (a) to (c). Step (a) is typically practiced by applying an acrylic styrene latex as a barrier coating (for example available from Northwest Coatings Corp., Northwest Aqueous Barrier Coating, no. 20951) weighing between approximately 318 to 386 gm [.7 to .85 pound] per ream (eg approximately .318 to .363 g (.70- .80 pound per ream) .A "ream" as used in the present specification and claims, refers to the amount of substrate or paper that is, or is equivalent to 500 sheets of paper of .43 to .56 meters [17 x 22"]. Stage (b) is typically practiced when applying as the silicone release coating curable with a UV-curable silicone at a weight of between about 182 to 227 g [.4 to .5 pound] per ream The method may also comprise the additional step of forming the sheet or web into a Roll configuration.

The method as described above can also be practiced in such a way that the processed stamp is a canceled stamp, in which case the method comprises the additional steps of applying the adhesive on the background face to a mailpiece, and applying the canceling tape in the form of a cancellation image to the upper surface of the stamp, such that a sufficient quantity of the ink is absorbed or otherwise retained by the upper surface, such that the cancellation image is visible and does not detach easily during automated processing, and manual handling of the mailpiece. In accordance with another aspect of the present invention, a canceled postal stamp is provided comprising: a substrate having top and bottom surfaces. Postal stamp signs formed in image on the upper side. A barrier coating that improves the absorption of release material or improves porosity in the upper face. An adhesive release coating on the barrier coating. A pressure sensitive adhesive that coats the bottom face. The stamp cancellation ink in a cancellation pattern on the release liner. And, the properties of barrier coating and coating weight, and the properties of release material and coating weight, such that the stamp cancellation is absorbed or otherwise retained on the upper face in such a manner that the pattern of visible stamp cancellation and the ink is not cleaned or detached the adhesive does not adhere to the top face. The specific barrier coating for the canceled stamp, and its application weight are preferably as described above. The release coating ** is preferably V-cured silicone applied at a weight of between about 182 to 227 g [.4 to .5 pound] per ream, but may be thermally cured silicone based on water under some circumstances. The substrate is preferably about 0.90 to 12.72 g [20 to 28 pounds] per ream of paper, such as 10 kg [24 pounds] of available Union Camp paper. The adhesive can be hot melt adhesive or other permanent pressure sensitive adhesive of conventional type, or under some circumstances may comprise a removable adhesive or repositionable adhesive (such as the "CLEANCAT 3" adhesive available from Moore USA of Lake Forest, Illinois. In accordance with another aspect of the present invention, a postage stamp is provided which comprises: a paper substrate having top and bottom faces, an adhesive or pressurized presses on the bottom face, and stamp signals on the top side. A latex stretch acrylic for barrier coating formation that is applied to the top face in an amount between about .43 to .56 <m by 500 sheets of resman (.7 to .8 pound for [17 x 2I1 '] of substrate sheets.A material for UV curable silicone release, which is applied on the barrier coating to a weight between approximately 182 to 227 g [.4 to .5 pound] for .43 to .56 m [17 x 22"] ream of 500 sheets of .43 to .56 m of substrate paper According to yet another aspect of the present invention, an unlined postal stamp structure is provided comprising: a weft of a plurality of postage stamps comprising a substrate material with pressure sensitive adhesive on a first side, and having a second face with release material that does not adhere to the adhesive but will absorb or otherwise retain ink for stamp cancellation, substantially permanently in sufficient quantity so that a cancellation pattern thereof is clearly visible. And, the weft is a roll configuration with adhesive of one stamp that couples the release material of another. ____ a __? ____________________________________ ^ The objective of the present invention is to provide an unlined postage stamp, so that it can effectively retain the cancellation pattern applied to it. These and other objects of the invention are apparent from the present description and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of exemplary method steps according to the present invention; Figure 2 is a schematic side view, with the components greatly exaggerated in size for clarity of illustration, of an exemplary unlined postal stamp according to the invention; Figure 3 is a top perspective view of a sheet of individual stamps in accordance with the present invention; Figure 4 is a schematic side illustration of a postal stamp structure according to the present invention in a funky configuration; and Figure 5 is a top detail view of an envelope with a canceled stamp according to the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS Figure 1 schematically illustrates an exemplary method according to the present invention wherein a web or sheet 10 is actuated to produce postage stamps. The weft or sheet 10 forms the substrate for the postal stamps finally produced and preferably is paper or a material with porosity similar to paper. More conveniently, the paper weighs between about 9.09 to 12.72 kg [20 to 28 pounds] per ream, for example about 10 kg [24 pounds] of Union Camp paper. Typically, the first step in practicing the method illustrated schematically in Figure 1 (although many of the steps can be reviewed in order) is the application of postal stamp signals as indicated by box 11 in Figure 1 to the upper face of the web or sheet 10. Then, a barrier coating is applied over the postal stamp signals, as indicated by step 12, and the releasable coating material is applied over the barrier coating as indicated in 13. The indicated stage by box 12, preferably practiced using an acrylic styrene latex formulation as the barrier coating, although any other barrier coating that sufficiently improves porosity, or absorption of release coating, of - ^ y.-The upper face of the leaf or frame 10, can be used. An exemplary commercially available material is product No. 20951 or 20951A, available from Northwest Coating. A comparison of some physical properties of these chemicals is picked up follows. 20951 20951A Visibility Brookfield @ spindle # 2, RVF 900-1400 cps 900-1400 cps 23. 89 to 25.00 ° C (70 and 75 ° F) 20 RPM pH 8.0-9.0 8.75-9.25 Solids 36-39% 35-39% The barrier coating step is typically practiced as indicated in box 12 by applying approximately 318-386 gm [.7 to .85 pound] per ream (eg, between about .327 a. 363 kg (.72 to .80 lb.) evenly The release coating applied in box 13 in Figure 1 is preferably a silicone covered by V, such as General Electric Silicone 9300 or Goldschmidt Silicone 70% RC-711 and 30% RC-726. Stage 11 is typically practiced by a press or other image forming device, while steps 12 and 13 can be practiced using flexographic techniques, a gravure press or a conventional Meyer rod.

The FigurlPt method also includes - as indicated by box 14 - application of pressure sensitive adhesive of the bottom face of the weft or LO sheet. The pressure sensitive adhesive that is applied in the box 10 can be any suitable pressure sensitive adhesive, preferably a permanent adhesive such as hot melt adhesives (such as Findley 2181) although it can also be a removable or repositionable adhesive (such as as CLEANCAT 3 adhesive available from Moore USA). The adhesive can be water based instead of hot melt, and is applied to the bottom face of the weft or sheet 10 using any suitable conventional technique, such as by a groove matrix. Box 15 of Figure 1 indicates the formation of the frame or sheet 10 on individual separable stamps. Step 15 may be practiced before step 11, or almost anywhere else in the process, and is practiced by providing weakening lines (such as conventional stamp perforations, die cuts or the like) in the weft or sheet 10 using equipment for cutting with matrix or conventional drilling or similar. After the unlined stamps are produced, they can be formed into a roll or stack as indicated by box 16 in Figure 1. The roll can be formed by slotting the stamps onto the direction of movement of the weft or sheet 10. during the practice of stages 11 to 15, such that the roll is only one stamp wide. The stacking of the sheets can be formed by any conventional technique, and the weft can cut off stamps on each sheet before they are stacked. The roll or stack formed in step 16 is used when separating individual stamps from the roll or stack as schematically indicated by box 7 in Figure 1. The separation can be done manually or using the conventional automatic type. The separate stamp is applied to a piece of mail, as indicated in box 18 in Figure 1, such as an envelope, packing or postcard. The piece of mail is sent by mail and finally the stamp is canceled - as indicated by box 19 in Figure 1 - using conventional automatic USPS stamp cancellation equipment. The stamp cancellation equipment applies a cancellation pattern, with cancellation ink, to the upper face of the stamp, while the pressure sensitive adhesive on the bottom face of the stamp adheres to the mail piece. Figure 2 is a side cross-sectional view, with elements greatly exaggerated in thickness and -Sid il the outline for illustration clarity of an exemplary unlined stamp according to the invention. The stamp 20 comprises a substrate 21, preferably approximately 9.09 to 12.72 kg [20 to 28 pounds] per ream of paper, with one top face 22 and one bottom face 23. On the bottom face 23 is a layer of adhesive conventional pressure sensitive 24 such as hot melt adhesive. On the upper face 22 are the postage stamp signals, indicated by the reference number 25, which typically includes the amount of postage or postage and some kind of stamp. On the signals 25 are applied and in contact with the upper face 22 is the barrier coating material 26 such as the Northwest Coatings 20951 material previously described. The material 25 has a relatively heterogeneous surface, as indicated schematically at 27 in Figure 2, and functions to improve the porosity or absorption of release coating of the upper face 22 of the stamp 20. On the barrier coating 26 the release material 28, such as conventional UV curable silicone as described above, or thermally cured silicone based on water. Typically, the barrier coating 26 has an approximate weight of 318 to 386 gm [.7 to .85 pound] per ream., for example between about 9.09 to 12.72 kg [20 to 28 pounds] per ream, while the silicone coating 28 has a weight of about 182 to 227 gm [.4 to .5 pound] per ream. Figure 3 illustrates a sheet 30 of individual stamps 20 according to the invention, each of the individual stamps JPP are separated from each other by conventional weakening lines 31 in this case lines of perforations. The upper left corner of the cutting end of the sheet 30 is shown flipped back to show the pressure sensitive adhesive 24 on its bottom face 23. When the sheets 30 are stacked, the pressure sensitive adhesive 24 of a sheet 30 will not adhere to the release liner 28 in the underlying sheet 30. Figure 4 schematically illustrates a postal stamp structure according to the present invention in roll configuration, shown generally by reference number 34 in Figure 1. The roll it has a width of one stamp with each of the stamps 20 again separated by lines of weakness such as lines of perforations 31. In a configuration on the roll 34, the pressure sensitive adhesive 24 of the outer stamps couples the coating of release 28 of the inner stamps and do not adhere to each other.

Figure 4 also schematically illustrates a stamp 20 applied to a mailpiece 35 such as an envelope, package or postcard. The pressure-sensitive adhesive 24 of the stamp 20 is applied to the address surface 36 of the mail piece 35, the pressure causes the adhesive 24 to adhere securely to the face 36 and in fact to permanently adhere if the adhesive 24 is permanent adhesive, such as the Findley 2181. The mail piece 35 is subsequently mailed and processed by the USPS. During processing, using conventional equipment, a cancellation pattern is applied on the stamp 20 using the cancellation ink. For example, Figure 5 shows a canceled version 20 'of the stamp 20 of Figure 4 on the mail piece 35 after the cancellation pattern / ink 38 is applied to it. Due to the properties of the top surface 22, as modified by the particular application of the barrier coating 26, and the release material 28 according to the invention, the ink / cancellation pattern 38 is clearly visible on the stamp 20 ', and does not easily come off during automated processing and the manual handling of the mail piece 35.

W The ink in the pattern 38 is typically available from American Coding and Marking Co., referenced with USPS 914M2B cancellation ink. While the invention herein has been illustrated and described in what is currently conceived as the most practical and preferred embodiment, it is apparent to those of ordinary skill in the art that many modifications may be practiced within the scope of the invention to this extent. it will grant it the broadest interpretation of the appended claims in order to cover all equivalent processes and products. £ 3iSS .. *. <

Claims (13)

1. CLAIMS 1.- Method for producing a postal stamp without lining, from a weft or sheet having upper and bottom faces, comprising the steps of: (a) applying a barrier coating to the upper face of the sheet or web; (b) applying a pressure sensitive adhesive to the bottom face; (c) applying an adhesive release material, which does not adhere to the adhesive in step (b), to the barrier coating of step (a); and (d) forming the weft or sheet into separable postage stamps, with postage stamp signs on the upper face; and characterized in that: step (a) is practiced by applying a barrier coating that improves the release coating absorption or improves the porosity, and steps (a) and (b) are practiced to provide sufficient porosity to the upper face , such that it can absorb or otherwise retain sufficient stamp cancellation ink, such that the ink is visible on the upper face once it is applied and dried.
2. 2.- Method of compliance with the claim 1, characterized in that further step (d) is practiced by (di) applying postal stamp signals to the upper face before the practice of step (a) and (d2) forming weakening lines in the sheet or frame to define the borders of individual separable stamps.
3. 3. - Method according to claim 2, characterized in that stage (di) is practiced before steps (b) and (c).
4. 4. - Method according to any preceding claim, characterized in that further step (a) is practiced by applying a barrier coating of latex acrylic styrene formulation to a weight of between about 318 to 386 gm [.7 to .85 pound] per ream.
5. 5. - Method according to any preceding claim, characterized in that further step (c) is practiced by applying as the UV-curable silicone release coating to a weight between about 182 to 227 gm [.4 to .5 pound] ] by ream.
6. 6. - Method according to any preceding claim, characterized by the additional step of forming the web or sheet in a roll configuration.
7. 7. - Method of compliance with any preceding claim, characterized in that the elaborate stamp is a canceled stamp and characterized by the additional step of applying the adhesive on the background face to a piece of correspondence, and apply cancellation ink on the form of a cancellation image to the upper surface of the stamp, such that a sufficient quantity of the ink is absorbed or otherwise retained by the upper surface, such that the cancellation image is visible and not visible. clean or detach easily during automated processing and manual handling of the mailpiece.
8. 8. A canceled postage stamp comprising: a substrate having upper and lower surfaces; postage stamp signs formed in image on the upper face; a barrier coating on the upper face; an adhesive release coating on the barrier coating; a pressure sensitive adhesive that coats the bottom face; and stamp cancellation ink in a cancellation pattern in the release liner; characterized in that the barrier coating comprises a barrier coating which improves the absorption of release material or improves the porosity, and the properties of the barrier coating and the coating weight and the release material properties and the coating weight, are such that the Stamp cancellation ink is absorbed or otherwise retained by the top face, such that the stamp cancellation pattern is easily visible and the ink does not easily peel off, and the adhesive does not adhere to the top face. ^ ¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡
9. 9. - A postage stamp canceled in accordance with claim 8, characterized in that the barrier coating is also an acrylic styrene latex formulation applied at a weight between about 318 to 386 gm [.7 to .85 pound] per ream of 500 sheets of substrate paper from .43 to .56 [17]. x 22"]
10. 10. A postage stamp canceled in accordance with claim 8 or 9, further characterized in that the release coating is silicone 10 cured by UV that is applied at a weight of between about 182 to 227 g [.4]. a .5 pound] per ream of 500 sheets of substrate paper of .43 to .56 m [17 x 22"].
11. 11. A postage stamp canceled in accordance with claim 8, 9 or 10, characterized 15 also because the substrate is approximately 9.09 a
12. 12. 72 kg [20 to 28 pounds] per ream of 500 sheets of substrate paper of .43 to .56 m [17 x 22"] 12. - A postage stamp canceled in accordance with claim 8, 9, 10 or 11, 20 further characterized in that the pressure sensitive adhesive comprises hot melt adhesive or repositionable adhesive.
13. 13. A postage stamp canceled in accordance with claim 8, 9, 10, 11 or 12, _____ further characterized the barrier coating has a non-uniform surface. __afc__Ba) »_« «MM-C-« ^^ H > s? ^ ¿tf4 £ l ^^^^ j ^ S? i- < ^ "Uki ^^^^ i_