WRITABLE DOCUMENT PROTECTOR ASSEMBLY
Field of the Invention
This invention relates to transparent sheet or document protectors.
Background of the Invention It is often desirable to provide protection for important documents or other materials.
Such protection has often been in the form of transparent envelopes or pockets which are closed on three sides but which have one side open to receive the material.
These document or sheet protectors are often formed of transparent sheet material such as polyolefin, specifically polypropylene sheet material. With documents or other material within the sheet protector, it would be desirable to be able to write on the transparent plastic and make notes relative to the visible material within the document protector. However, polypropylene and most other transparent plastic materials do not readily accept writing with a pen or the like.
To overcome this problem, it has been proposed to apply a topcoat layer using a solvent which is removed by drying, leaving an ink receptive coating. However, such top coats often lack durability and can flake off and in some cases interfere with the manufacturing steps involved in the formation of the document protector.
Summary of the Invention In accordance with one aspect of the invention, an ink writable transparent document protector is formed by a co-extrusion process in which water-insoluble plastic, such as polypropylene, is co-extruded with a blend of water-insoluble material and water-soluble material, thereby forming an integral transparent film that is writable and that has good mechanical properties. The resultant film is formed into an envelope or pocket, and subsequently one can write on the document protector using virtually any kind of ink.
In one preferred embodiment, a large sheet of the co-extruded material is folded over to form an envelope, and two of the three remaining edges are heat bonded together to form the document protector, closed on three sides and open on the fourth side. This configuration permits the insertion of a sheet, such as a document, photograph, or any other material requiring
protection. The document protection assembly may be provided with reinforcing along one edge, and holes to facilitate mounting in a ring binder. For reinforcing, an additional strip of plastic sheet material may be heat sealed into the edge of the document protector, thereby providing three plastic layers through which the holes are made to increase the strength at this vulnerable area.
The sheet protectors are also suitable for use in photo albums where the pages may include writable transparent pockets for receiving photos.
Now, returning to the extruded sheet material per se and as mentioned above, reference is made to U.S. Patent Application Serial No. 09/547,942, filed April 11, 2000, with this prior application being incorporated into this application in its entirety by reference.
One particular embodiment of the present invention is a photograph sheet protector having one or more pockets in which photographs may be inserted. The end-user may write on one or both exterior surfaces of the sheet protector without damaging the photograph.
Embodiments of the document protector made as described above are of high strength, and specific embodiments may be receptive to virtually any kind of ink and be fully transparent.
Other objects, features, and advantages of the invention will become apparent from a consideration of the following detailed description and from the accompanying drawings.
Brief Description of the Drawings Fig. 1 is a plan view of an illustrative embodiment of the invention;
Fig. 2 is a cross-sectional view taken along line 2-2 of Fig. 1 ; Fig. 3 is a cross-sectional view of sheet material which may be employed to form the sheet protector of Fig. 1;
Fig. 4 is a cross-sectional view of an alternative sheet construction; Fig. 5 is a schematic showing of a co-extrusion apparatus for forming the sheet material of Figs. 3 or 4;
Fig. 6 shows sheet protector arrangements illustrating the invention used in a photo album;
Fig. 7 is a cross-sectional view taken along line 7-7 of Fig. 6; Fig. 8 is a schematic showing of one of the photos of Fig. 6 with notes on the sheet protector;
Fig. 9 is a plan view of a sheet protector having pockets for placing photographs and other documents therein;
Fig. 10 is a cross-sectional view of the sheet protector of Fig. 9;
Fig. 11 is a photo album having a sheet protector with photographs placed in pockets;
Fig. 12 is a side view of a double-sided sheet protector showing pockets on either side of the sheet protector for holding photographs; and
Fig. 13 is a schematic showing of one pocket holding a photograph and having notes written on the sheet protector.
Detailed Description of Preferred Embodiments
Returning more particularly to the drawings, Figure 1 is a plan view of a sheet protector 10, which includes an upper transparent plastic sheet 12 and a lower transparent plastic sheet 14. These two sheets may be formed from a single sheet folded over at the outer edge 16, or alternatively can be made of two overlying sheets. The sheet protector 10 may be open at the top edge, as shown in Figure 1, but may be heat sealed along the lower edge 18 and may be heat sealed along lines 20 and 22 with an extra reinforcing strip 24 mounted between the thermo- sealing lines 20 and 22. The reinforced left edge of the sheet protector 10 may be provided with three or more holes 26 for convenience in mounting the sheet protector into a three-ring binder. The heat sealing may be accomplished by applying a heated die to the double layer material. The heat sealing may be in the form of a series of welds with spaces between the welds to allow for the easy insertion of sheet material. Instead of thermal bonding, the edges may be secured together in any desired manner, by high frequency welding, by a thin line of permanent adhesive, or by other known techniques. Concerning the size of the sheet protector, one sample sheet protector was approximately nine inches in width and about 11-1/8 inches in its longer dimension. The reinforcing strip 24 was about 3/8 inch wide. The pocket was large enough to receive an unfolded sheet, 8lΛ inches by 11 inches in size. Each of the co-extruded sheets was about 3 or 4 mils thick.
Referring back to Figure 1 of the drawings, within the sheet protector 10 is shown a letter 32 protected from damage by the sheet protector 10. Written on the outer surface of the sheet protector in ink are certain legends 34 calling attention to certain passages or parts of the
letter 32. Thus, by using the writable sheet protector of Figure 1, comments may be made relative to the letter 32 without defacing the letter itself. Subsequently, if desired, the original letter 32 may be withdrawn from the envelope.
Figures 3 and 4 are detailed cross-sectional views indicating the implementation of the transparent sheet material employed in the sheet protector of Figures 1 and 2 of the drawings. More specifically, referring to Figure 3, the sheet material 42 may include a base layer 44 of transparent plastic which is water insoluble, such as polypropylene. The upper layer 46, which is co-extruded with the lower layer 44 is a writable layer and may be a blend of non- water-soluble material and water-soluble material, such as a blend of poly vinyl alcohol and polypropylene or of polyalkyl oxazaline and a polyolefin, such as polypropylene. Concerning Figure 4, this shows a three-layer assembly of transparent plastic materials involving a water-insoluble base layer 52, a writable layer 54, which is made up of a blend of non- water-soluble and water-soluble polymeric material, with an intermediate layer 56, which is provided to help bond the upper and lower layers 52 and 54 to one another when they are being co-extruded. Figure 5 is a schematic block diagram illustrating the co-extrusion process. In Figure 5, the materials to be co-extruded are provided in the input containers 62" and 64, with the input container 66 being provided in cases where a three-layer transparent laminate is being formed. The upper container 62 may contain heated material for forming the writable top layer, while the container 64 may contain the heated plastic material for forming the water insoluble lower layer of the laminate. Heated material from container 62 and 64, and also 66 when an intermediate layer is desired, are fed to the feed block 68 and the die 70, which extrude the multiple-layer heat material 72, which is eventually wound up onto a reel 74.
Figures 6, 7, and 8 of the drawings show another use of the present invention. More specifically, referring to Figure 6, a photo album 82 is provided with a front cover 84, a rear cover 86, and pages which are formed of transparent pockets 88 mounted on a paper or a light card page sheet 90. Each of the pockets 88 include an inner layer 92 and an outer layer 94 which is writable. The inner layer 96 may be fastened to the supporting page 90. Alternatively, instead of being mounted on the page 90, the sheet protectors themselves may be the pages of the photo album with these transparent pages being bound directly into the photo album or through mounting arrangements such as removable screws or the rings of a three-ring binder.
Figure 8 is a front view of one of the pockets 88 with a photograph 100 mounted in the document protector. Legends 102 and 104 may be added in ink on the outside of the document protector to indicate the place where the photograph was taken, and the names of persons or objects in the photo. Now, for completeness, a portion of the specification of the prior cited patent application relative to the sheet material per se will now be explicitly included in the present patent application.
Ink receptive substrates to be employed as the sheet material comprise a base layer formed from a water-insoluble thermoplastic polymer, and an ink receptive layer disposed over the base layer. The ink receptive layer is formed from a melt processable blend of a water- soluble polymer and a substantially water-insoluble polymer, and provides an inherently ink receptive surface without further surface treatment. A tie layer can optionally be interposed between base and ink receptive layer.
The base layer is selected from the group of thermoplastic material consisting of polyolefins, polyesters, polyurethanes, poly vinyl chlorides, polyamides, polystyrene, ethylene vinyl alcohol, and mixtures thereof. The ink receptive blend comprises in the range of from 20 to 80 percent by weight water-soluble polymer, and in the range of from 20 to 80 percent by weight substantially water-insoluble polymer based on the total weight of the blend. The blend may include an optional compatibilizing agent that is chemically compatible with both the water- soluble polymer and the substantially water-insoluble polymer.
The blend has a melting temperature in the range of from about 100 to 600°F. The water- soluble polymer component of the blend is selected from the group of compounds consisting of polyvinyl alcohols, polyalkyl oxazolines, polyphenyl oxazolines, polyvinyl pyrrolidones, polyacrylic-acids, polymethyl methacrylates, polymethyl methacrylic-acids, styrene maleic anhydrides, alkyl celluloses, carboxyalkyl celluloses, hydroxyalkyl celluloses, polyethylene oxides, polyethylene-imines, and mixtures thereof.
Preferred water-soluble polymers include polyalkyl oxazoline and polyvinyl alcohol. The substantially water-insoluble polymer component of the blend is selected from the group of polyolefins consisting of modified and unmodified polyesters, polypropylenes, polyethylenes, polystyrenes, polybutylenes, and copolymers and mixtures thereof.
In a preferred embodiment, the base layer and ink receptive layer of ink receptive substrates are formed simultaneously by co-extrusion process. Ink receptive substrates can include the ink receptive layer on one or both surfaces of the base layer, and/or can be constructed in the form of a pressure-sensitive adhesive label, i.e., with a pressure-sensitive adhesive material disposed on a surface of the base layer opposite the ink receptive layer.
The ink receptive substrates are inherently ink receptive in that they avoid that need for top-coating or reliance on a voided microstructure to gain ink receptivity. The ink receptive substrates provide properties of image quality and optics that are superior to those provided by substrates having voided microstructures. The ink receptive substrates are fabricated in a manner that avoids the need for multiple time-consuming and costly process steps.
Considering now one example of a specific embodiment of the invention, the sheet protector may be a writable assembly for protecting photographs. Generally speaking, one of the many embodiments of this invention relates to embodiments of writeable photo pages. The pages are one or two-sided photograph-holding, pocketed sheet structures that include two generally clear sheets, and a backing or central sheet that is typically white or opaque. The page includes an area for holding at least one photograph. In many embodiments, each clear sheet is subdivided into a series of areas for holding photographs. The pockets are preferably rectangular, but may be other shapes. A series of strips or other areas act as borders surrounding the photo pockets. The strips are typically not as wide as the photo pockets. In many embodiments of the invention, the clear sheeting permits writing with water- based writing instruments, such as ball-point pens and roller-ball pens, and/or other writing instruments with solvent-based or other ink, and/or inkjet or other printers.
In one embodiment, the photo pages include two sheets of coextruded ERSA material, as described above. A central backing sheet of white polyester film is interposed in between the two clear sheets. Photo pockets and marginal areas are defined by weld lines, which may be formed by conventional methods known in the art.
The outer surface of one or both sheets is adapted to receive and retain writing from a writing instrument, and may alternatively receive printing from a printer, such as from an inkjet printer. For example, the writable photo pages may permit the user to inscribe both the clear sheeting over the photographs, and the border areas of the clear sheeting, to illustrate, one might
circle an area of a landscape photograph and write in the margin, "This is where we intend to build our new home."
While one specific embodiment relates to holding and protecting photographs, alternative embodiments may hold business cards, trading cards, or the like, rather than photographs. Considering now specific embodiments, and referring to Figures 9 - 13, Figure 9 is a plan view of a sheet protector 210, which is formed from a transparent sheet 212. The sheet protector 210 is double-sided, as shown in FIG. 12, and includes a front transparent sheet 214 and a back transparent sheet 216 formed from the transparent plastic sheet 212. These first and second sheets 214 and 216 may be formed from the transparent sheet 212 by folding the transparent sheet 212 over at the outer edge 218. In an alternative embodiment, the double-sided sheet protector 210 can be made of two separate, overlying transparent sheets to form front and back transparent sheets 214 and 216.
The sheet protector 210 may be open near the top edge, as shown in FIG. 9, for placing documents in the sheet protector 210. The sheet protector 210 may also be heat sealed along the lower edge 220 and may be heat sealed along lines 222 and 224 with an extra reinforcing strip 226 mounted between the thermo-sealing lines 222 and 224. The reinforced left edge 228 of the sheet protector 210 may be provided with one or more holes 30 for convenience in mounting the sheet protector 10 into a ring binder.
FIG. 9 shows one embodiment in which the sheet protector 210 is configured to hold two photographs on a side of the sheet protector 210. In an additional embodiment, the sheet protector 210 is configured to hold three or more photographs on a side. It should be understood that the sheet protector 210 can be configured to hold multiple photographs of varying sizes on each side. Any number of pockets may also be used on each side, such that consumers can use different sheet protectors 210 depending on the size of their photographs, or on the number of photographs they wish to display on a given side of the sheet protector 210.
FIG. 10 is cross-sectional view of the sheet protector 210, also includes a backing sheet 232 positioned between the front transparent sheet 214 and the back transparent sheet 216. The backing sheet 232 may be an opaque sheet made from polypropylene material. The backing sheet 232 is placed the front and back transparent sheets 214 and 216 to provide a separation layer such that different documents can be placed between the front transparent sheet 214 and the backing sheet 232, and between the back transparent sheet 16 and the backing sheet 232.
Heat sealing of the front and back transparent sheets 214 and 216 may be accomplished by applying a heated die to the double layer material. The heat sealing may be in the form of a series of welds with spaces between the welds to allow for the easy insertion of sheet material. Instead of thermal bonding, the edges may be secured together in any desired manner, by high frequency welding, by a thin line of permanent adhesive, or by other known techniques. The size of the sheet protector may vary depending on the size of the document or photograph to be placed therein. For example, one sheet protector is approximately nine inches in width and about 11-1/8 inches in its longer dimension. The reinforcing strip 24 is about 3/8 inch wide. The pocket is large enough to receive an unfolded sheet, 8 2 inches by 11 inches in size. Each of the co-extruded sheets was about 3 or 4 mils thick. In another embodiment, the sheet protector is the size of a conventional photo album. Multiple pockets may be formed on the sheet protector for holding several photographs per page. Pocket size is large enough to hold standard photographs, such as for example a 3 inch by 5 inch photograph.
Referring back to the drawings, within the sheet protector 210 a photograph 234 can be placed to be protected from damage by the sheet protector 210. Written on the outer surface of the sheet protector in ink are certain legends 236 calling attention to certain parts of the photograph 234. Thus, by using the writable sheet protector of the present invention, comments may be made relative to the photograph 234 without defacing the photograph itself. Subsequently, if desired, the original photograph 234 may be withdrawn from the sheet protector 210. Note from Figures 9-13 that multiple photographs may be placed in the sheet protector 210 and that different legends 236 can be made upon the sheet protector 210 regarding different photographs 234 placed the various pockets of the sheet protector 210.
The material used to make the transparent sheet 212 may include a base layer of transparent plastic which is water insoluble, such as polypropylene. The upper layer, which may be co-extruded with the lower layer, is a writable layer and may be a blend of non- water-soluble material and water-soluble material, such as a blend of polyvinyl alcohol and polypropylene or of polyalkyl oxazaline and a polyolefin, such as polypropylene. An intermediate layer may also be used to help bond the upper and lower layers to one another when they are being co-extruded. In another embodiment, ink receptive substrates to be employed as the sheet material comprise a base layer formed from a water-insoluble thermoplastic polymer, and an ink receptive layer disposed over the base layer. The ink receptive layer may be formed from a melt
processable blend of a water-soluble polymer and a substantially water-insoluble polymer, and provides an inherently ink receptive surface without further surface treatment. A tie layer can optionally be interposed between base and ink receptive layer.
The base layer may be selected from the group of thermoplastic material consisting of polyolefins, polyesters, polyurethanes, polyvinyl chlorides, polyamides, polystyrene, ethylene vinyl alcohol, and mixtures thereof. The ink receptive blend comprises in the range of from 20 to 80 percent by weight water-soluble polymer, and in the range of from 20 to 80 percent by weight substantially water-insoluble polymer based on the total weight of the blend. The blend may include an optional compatibilizing agent that is chemically compatible with both the water- soluble polymer and the substantially water-insoluble polymer.
The blend has a melting temperature in the range of from about 100 to 600°F. The water- soluble polymer component of the blend is selected from the group of compounds consisting of polyvinyl alcohols, polyalkyl oxazolines, polyphenyl oxazolines, polyvinyl pyrrolidones, polyacrylic-acids, polymethyl methacrylates, polymethyl methacrylic-acids, styrene maleic anhydrides, alkyl celluloses, carboxyalkyl celluloses, hydroxyalkyl celluloses, polyethylene oxides, polyethylene-imines, and mixtures thereof.
Preferred water-soluble polymers include polyalkyl oxazoline and polyvinyl alcohol. The substantially water-insoluble polymer component of the blend is selected from the group of polyolefins consisting of modified and unmodified polyesters, polypropylenes, polyethylenes, polystyrenes, polybutylenes, and copolymers and mixtures thereof.
In one embodiment, the base layer and ink receptive layer of ink receptive substrates are formed simultaneously by co-extrusion process. Ink receptive substrates can include the ink receptive layer on one or both surfaces of the base layer, and/or can be constructed in the form of a pressure-sensitive adhesive label, i.e., with a pressure-sensitive adhesive material disposed on a surface of the base layer opposite the ink receptive layer.
The ink receptive substrates are inherently ink receptive in that they avoid the need for top-coating or reliance on a voided microstructure to gain ink receptivity. The ink receptive substrates provide properties of image quality and optics that are superior to those provided by substrates having voided microstmctures. The ink receptive substrates are fabricated in a manner that avoids the need for multiple time-consuming and costly process steps.
FIG. 11 shows another embodiment of the present invention. A photo album 238 is provided with a front cover 240, a rear cover 242, and a sheet protector 210. A photo album 238 can have multiple sheet protectors 210 placed therein, each being single or double sided and holding photographs 234. FIG. 12 is side of a double sided sheet protector 210 showing openings 244 at the position in the pockets where photographs 234 can be entered and withdrawn. Also shown in FIG. 12 is the central backing sheet 232 showing the separation between photographs placed in the pockets between the front transparent sheet 14 and the back' transparent sheet 216. Figure 13 is a front view of one of the pockets 246 with a photograph 234 mounted in a pocket of the sheet protector 210. Legends 236 may be added in ink on the outside of the sheet protector 210 to indicate, for example, the place where the photograph was taken, and the names of persons or objects in the photo. The transparent sheet 212 is receptive to aqueous, solvent based and gel based ink, and the ink is also substantially water-fast once it has dried. In closing, the foregoing detailed description and drawing relate to preferred embodiments of the invention. However, it is to be understood that various modifications can be made without departing from the spirit and scope of the invention. Thus, by way of example and not of limitation, other sheet protectors may be formed in addition to those shown in Figs. 1, 2, and 6 through 8. Also, the thickness of each of the co-extruded layers may vary but are preferably between about 2 and 5 mils; and the sheet protectors may have varying sizes to hold 8 2 by 11 inch sheets, 8 by 14 inch sheets, and standard size photos, for photo album pages. In addition, other materials which perform substantially the same functions may be employed to form co-extruded writable document protectors. Accordingly, the present invention is not limited to the embodiments described in detail hereinabove and shown in the drawings.
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