Abstract:
A business form such as a wristband or label includes an imaging area of face stock overprinted with a fluorescent ink for receiving a printed bar code to enhance the scannability of the bar code. The ink may be applied by overprinting to a thickness of between about 0.2 to about 0.5 mils, and even more preferably to a thickness of about 0.2 mils. The overprint ink is also print receptive allowing a bar code to be printed onto it with no deleterious effects. The imaging area of the wristband form may be overlaminated and the bar code scannability will still be enhanced. An alternative embodiment comprises a face stock manufactured to have a finished surface exhibiting a fluorescent effect similar to that achieved by overprinting through mixing in appropriate components as the face stock is made.

Description:
CROSS REFERENCE AND PRIORITY CLAIM TO RELATED APPLICATION 
       [0001]    This non-provisional application claims priority to related provisional application having Ser. No. 60/798,605, and filing date May 8, 2006. 
     
     BACKGROUND AND SUMMARY OF THE INVENTION  
       [0002]    Bar codes are becoming ubiquitous in our society and especially for use in medical settings. This is increasingly so as there has been a general movement to more carefully monitor the identity of patients and correlate to each patient the various kinds of medications/treatments he receives and other aspects of his stay/treatment/etc. Some of this is being mandated by the passage of new laws requiring more discipline in these matters, and some of it is being adopted out of the desire to be able to more carefully ensure that each patient receives the proper care and treatment, and is billed for it appropriately. This is true in all kinds of medical environments, including in-patient care, out-patient care, emergency room care, pediatric care, nursing home care, mental health care, and virtually all other instances where accurate patient identification is needed. 
         [0003]    One of the co-inventors herein has been active in this area, and has invented numerous inventions that have been patented as an aid in identifying patients and correlating them with the various accoutrements of their status as a patient. See for example, U.S. Pat. Nos. 5,933,993; 6,000,160; 6,067,739; 6,438,881; 6,510,634; 6,748,687; 7,017,293; 7,017,294; and 7,047,682, the disclosures of which are incorporated herein by reference. Various of these disclosures are for wristbands and associated labels of various constructions which can be conveniently prepared at the same time and individually printed with identifying indicia, such as bar codes, for rapid and simple electronic reading with a wand or scanner for inputting patient data as well as data relating to any other desired information. For example, the labels may be removed from the form and used to identify blood or other tissue samples, medical charts, and even mundane items such as utensils, etc. for patients suffering from infectious or communicable diseases. 
         [0004]    As used herein, the term bar code is defined as any machine readable (typically through electro-optical processes) indicia, marking, symbol or a patterned or ordered arrangement of any such items which represents or contains data which is coded into the arrangement, layout, or other pattern thereof and readable at least by an electronic data entry device. Another common example of character reading other than strict bar code reading that is intended to be included by the inventors as falling within the concept of their invention is optical character reading. A bar code may also be decipherable without machine aid as well to ascertain the data contained therein, and such status does not exclude it from being considered as a bar code. A bar code may be applied to a surface through any of many means such as laser printing or the like. 
         [0005]    Reading and obtaining a successful input of the data contained in a bar code is not a simple matter. Standards have been set for this concept of “scannability” which relates to the probability of obtaining an accurate scan at a given distance between a bar code reader and a bar code. See, for example, ANSI INCITS 182 as well as ANSI verification guideline X3. 182-1990 Annex A. The greater the probability of obtaining a scan at a greater distance is indicative of a higher scannability. As bar codes are printed on wristbands, for example, and other surfaces which might not necessarily be exactly flat, and the reader may not be always aligned perfectly with the bar code or at the optimum reading angle, or the ambient light may not be ideal, and the printing of any bar code is necessarily subject to variations caused by the variations imparted by the printing process itself, an increased scannability is very important in ensuring that bar codes are accurately read, especially in a medical setting, as described above. 
         [0006]    Still another reason that scannability is important relates to the particular environment in many health care settings. When a patient is resident in a medical facility, and it is nighttime or in any other low ambient light environment, the care givers have difficulty in reading bar coded information from a patient&#39;s wristband or otherwise at nighttime or in any other low ambient light environment. A care giver would prefer not to turn on the lights and awake the patient, or might alternatively use a flashlight, but the absence of proper lighting creates problems in scanning the bar code. First of all, the caregiver must locate the patient&#39;s wrist where the wristband is located, but also the wristband is not presented in a reliably flat orientation meaning that bar code scannability becomes more important to obtaining an accurate read. While the co-inventor&#39;s prior inventions have helped immensely by presenting these bar codes in a large, sharply laser-printed font on a bright white face sheet background, either on the wristband or the accompanying labels, the scannability of the bar code itself still introduces the possibility of an error in acquiring or scanning the data. This is further impacted by the added workload and aging population of caregivers, along with the increased complexity of the care provided, resulting in more required patient interaction and increased numbers of times that a patient&#39;s ID must be verified, both day and night. Hence, there is a real need in this environment for a bar code with improved scannability. Some prior art attempts to improve scannability may be found in U.S. Pat. Nos. 4,575,625; 5,080,456; and 5,107,100, the disclosures of which are incorporated herein by reference. 
         [0007]    Improving contrast can help to compensate for the real world factors that tend to diminish scannability such as poor print quality on the bar code or the bar code design itself. Poor print quality results from, for example, a thermal transfer printer that has not been serviced properly, or that uses the wrong ink ribbon for the surface being printed, or is run at the wrong temperature settings-any of which may result in bar codes with gaps, thin spots where not enough ink has deposited, ragged edges, and areas where ink flows outside the area where it is supposed to be. Alternatively, bar code design factors to consider include bar codes with high density and low wide-to-narrow bar ratios which are more challenging to scan and read. These factors as well as the ordinary real world manufacturing tolerances inherent in printing a bar code onto a surface, as well as the real world inaccuracies inherent in a “read” attempt made “in the field” wherever that might be and the circumstances surrounding that “read” attempt place an increased emphasis on an improved scannability rating of a bar code under test conditions. 
         [0008]    Others have attempted to improve scannability of a bar code through use of fluorescent or phosphorescent ink, but these prior art attempts have centered on utilizing such inks for printing of the bar codes themselves. One such effort is found in U.S. Pat. No. 6,303,929, the disclosure of which is incorporated herein by reference. Another prior art patent (U.S. Pat. No. 4,724,309) has been found that makes use of such inks as a background, but the reference teaches that the ink may be used to mark specific zones of a bank draft for example where a user may enter handwritten or typed indicia that may then be optically read in blackout conditions by passing the bank draft under ultraviolet light. The location of the area is identified by the placement of the ink, and although the reference suggests that improved readability for optical scanning is achieved, the reference teaches that bar codes may be placed on the bank draft but not in one of these zones. Furthermore, the reference teaches that such a bar code could optimally be imprinted in the very same fluorescent or phosphorescent ink, much like the &#39;929 patent. Thus, while others have sought to improve bar code scannability through the use of these kinds of inks, the prior art has met with limited success. 
         [0009]    The inventors are also aware of fluorescent inks being used to coat labels for other purposes, some of which may accept bar codes. For example, one such popular category of label is marketed under the Dayglo™ trademark. These labels are generally coated with a bright, even garish, color fluorescent ink such as fuscia or lime green to draw an observer&#39;s eye to it and cause it to be noticed. One popular use of such labels may be found in supermarkets where price specials are marked on these labels and they then are placed amongst the shelves for the shopper to see as they scan the shelves looking for their food items to purchase. Other labels are coated with other kinds of fluorescent ink, such as the ones generally considered to fall in the category of “invisible” ink meaning that the coating is not viewable by the naked eye except under a special light, such as an ultraviolet light. These labels also may have been imprinted with bar codes and used in the prior art. While these labels are expected to be found in the prior art, the inventors are now aware that anyone has determined that coating a label with fluorescing ink before imprinting a bar code on it will improve its scannability. 
         [0010]    In attempting to solve the problem presented by trying to scan bar code imprinted wristbands, which inherently are difficult to read for the reasons given above, the inventors have for the first time determined that applying a fluorescing ink coating to an underlying substrate dramatically improves its scannability. Instead of printing the bar code itself in fluorescing ink, the method of choice as taught in the prior art for improving bar code scannability, the inventors have conceived of overcoating a patch or area of a print surface with the fluorescing ink instead and then printing the bar code directly onto it, such as with laser printing. This has been found to dramatically improve the scannability of bar codes printed onto the overcoated surface compared to an uncoated surface in virtually any level of ambient light and with virtually any bar code pattern. One key factor impacting scannability is the contrast ratio that can be obtained between the bar code and its background. The ideal has been believed to be obtained with a flat black bar code bar that adsorbs 100% of the light from the scanner printed on a bright white opaque surface that reflects 100% of the light. This ideal is impossible to achieve in the real world for reflecting light situations, for one reason that no reflective surface will reflect 100% of the light impacting it, but contrast ratios approaching 90% can be achieved. However, adding in the fluorescence feature dramatically improves the reflective light real world results and although the inventors haven&#39;t tested it scientifically, it is believed that using the present invention of fluorescent ink produces results approaching ideal. In testing, utilizing this fluorescent ink overcoat background has been found to add to this contrast ratio, as well as result in dramatically improved scannability ratings as reported below. This occurs when the fluorescent ink is energized by shorter wavelength “invisible” light in the 300 to 400 nanometer range thus emitting longer wavelength visible light in the 400 to 700 nanometer range, which can be better “seen” by the naked eye and the bar code reader by intensifying the contrast of the background to the black bar code. While not completely scientifically investigated or understood, the inventors believe it is the “fluorescing effect” of the coating that provides the dramatic improvement in scannability. Fluorescent inks do much more than merely reflect as they actually emit energy (radiation) in the form of visible light when energized by another light source (a bar code scanner) which emits a broad spectrum of light waves including UV in the 300 to 400 nanometer range needed to fluoresce the ink coating. In essence, a combination of the reflection from the white substrate plus the visible light emitting from the fluorescent ink amplifies the contrast of the black bars to the supercharged white background. 
         [0011]    The fluorescent ink used may be any of a range of inks, such as UV curable, water based and solvent based fluorescent inks and coatings, with the important consideration being its ability to increase the intensity of light returning from the background surface over that of an uncoated surface or a surface which does not exhibit a fluorescing or similar effect. As used herein, the term “fluorescing” or “fluorescent” ink may be understood to include all such inks, including luminescent inks as well. 
         [0012]    In an alternative embodiment, the inventors conceive of a paper stock layer made from a mix of materials such that the finished surface exhibits the reflective qualities similar to that of the layered coating of fluorescent ink of the first embodiment. In this embodiment, instead of an overcoating or layering of ink, which would require a separate additional step in manufacture, the inventors contemplate that the mixture of materials prepared in formulating the face stock during its manufacture would have added to it the appropriate materials as would be known to those of skill in the art to produce a face stock having a finished surface exhibiting the same desired fluorescing properties. The inventors are aware of brighteners, for example, that are routinely added to face stock mixtures which increase the brightness of the finished surface of the face stock, and contemplate that a similar such process could be used to achieve the purposes of the present invention. With this alternative embodiment, it is anticipated that fewer manufacturing steps would be needed. 
         [0013]    An overview of the invention has been provided herein. Further details of the invention may be learned by referring to the drawings and description of the preferred embodiment which follow. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0014]      FIG. 1  is a perspective view of a label or other business form having an overprinted layer of fluorescent ink with bar code printed thereon, and 
           [0015]      FIG. 2  is a perspective view of a label or other business form having a face stock appropriately made with materials resulting in a surface exhibiting fluorescing properties similar to that as if it had been coated with a layer of fluorescent ink. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0016]    As shown in the drawings, the present invention  20  involves applying a coating of fluorescent ink  22  to a carrier or face stock layer  24  of a business form and then printing a bar code  26  thereon. The face stock layer could be part of a self laminating wristband as may be die cut into the face stock layer  24  and an underlying laminate layer  30  adhered thereto with a layer of patterned adhesive  32  such that after separation of the wristband a portion of the laminate layer  30  may be folded over an imaging portion of the face stock layer  24  to protect the imaging portion. Examples of such wristband forms as well as exemplary labels may be found in any of several previously issued patents owned by the assignee hereof, as noted above. The bar code  26  is preferably printed on the face stock portion  24  so that it is protected by the overlying portion of the laminate layer  30 . This wristband construction is exemplary of several such wristbands as shown in the co-inventor&#39;s prior patents. Additionally, labels (not shown) may accompany the wristband on the same page sized form and may also be printed with an identifying bar code  26 . Although identified in the preferred embodiment as used with a wristband and accompanying labels, the present invention may be used with other applications as well. Anywhere a bar code (including OCR characters, as the term bar code has been defined above) may be printed onto a coated surface, the present invention is contemplated as improving the scannability of the bar code. For purposes of the present invention, a business form may also be considered as including any kind of prepared form, such as by pre-printing, and designed to accommodate, record or handle information in a commercial context whether or not the form is later printed or handwritten by a user to record additional information. Examples of documents which are business forms include shipping labels, labels of virtually any nature, inventory tags, insurance forms, financial instruments such as checks and other such forms, hang tags, ID forms, applications, admission forms, and other such similar forms that may contain a bar code for tracking or identification purposes. 
         [0017]    The ink may be applied in a range of acceptable alternative methods, such as by flexographic, letterpress, and gravure. Spray coating methods could work as well, but are not presently considered to be as practical due to the relative minimal thickness of the preferred coating. For convenience, any method as might be used to apply such a coating with be referred to herein as “overprinting”. As to thickness, the inventors believe that a nominal 0.2 mil depth or thickness is preferred. More preferably, the coating weight is desirably between about 0.2 mils up to a maximum of about 0.5 mils. The inventors have found that fluorescent coatings will achieve a good level of fluorescence at 0.2 mil thickness , will have a slight build in fluorescence up to 0.5 mils coating weight, and at over 0.5 mils fluorescence will begin to taper off. In the inventors&#39; latest testing, gloss level was not found to play an important role in improving scannability. Both gloss and matte finish coatings were evaluated and performed equally well for the most part, with the matte finish coating showing an advantage as the distance increased. As known by those of skill in the art, depending on the type of coating chosen to be applied, whether UV, water, solvent, thermal or otherwise, the fluorescence should preferably be tested by visually observing the film under a black light. The naked eye can detect differences in fluorescence when compared to “standard” or desired specimen fluorescence. Furthermore, the print receptivity of the coating is preferably tested by for example printing test bar codes on the coated stock using thermal transfer and toner transfer coating techniques, and then preferably visually observing bar code continuity and edge definition. Ink adhesion is preferably checked by using a 3M 600 pressure sensitive adhesive testing tape, or equivalent. 
         [0018]    The inventors have had testing performed to validate the improved contrast and scannability of a bar code, and the test results are shown on Exhibit A attached hereto. As the parameter of scannability is understood to be directly related to the contrast perceived by the character reader, as the reader typically shines a source light onto the bar code and then reads it through the light which returns to associated sensors also located in the typical reader, the present invention is thought to work by improving the perceived contrast between the bar code characters and the surrounding substrate. The letters shown are indicative of the letter grades found in the ANSI verification standard mentioned above. Briefly, the letter grade of A is best and F is worst. In the test, sixteen different sample/environment combinations were evaluated using a base stock of 4 mil white laser imprintable paper. The first variable compared the performance of paper that was either uncoated, standard fluorescence coated, or maximum fluorescence coated. The ink that was used was FT301LI UV Thermal/Laser Imprintable Topcoat for Flexographic Press, the high fluorescent version of same, and Fast Cure Matte LI. Typical properties of the inks that were used include viscosity of 270-330 cps @77 degrees F., and density of 8.90±0.1 pounds per gallon. The second variable compared the difference to be found in scanning the bar code either directly or with an over-lamination with a Flexicon Classics Plus 13092 1 mil semi matte polyester. The third variable compared the difference to be found in scannability in ambient light versus scanning in a shaded area or low ambient light. While the bar codes were printed digitally on an Indigo web printing unit, they were separately identified as BB (uncoated stock paper), CC (coated stock paper with fluorescent coating #1), DD (coated stock paper with fluorescent coating #2), and EE (coated paper stock with matte fluorescent coating #3) merely to track that they were applied to different surfaces. 
         [0019]    Briefly summarized, the test results showed an improvement of one to two inches to the HHP scanner&#39;s scan range for CC and DD, with an improvement of as much three inches for EE. As the HHP Quick Check 800 has an effective scan range of 2 inches to 6 inches on a bar code with 7.6 mil narrow bar elements, the addition of 1 inch to 2 inches of extra distance represents a 17% to 33% improvement in scan range, and an even greater improvement for EE. As between two of the fluorescent coatings tested there was no discernible difference in performance while the third ink tested showed better overall performance. The conclusion drawn is that standard print receptive fluorescent coatings will provide measurable improvement in scan range. One other high fluorescent sample not reported in this test did exhibit better results than those tested and reported on herein, but the ink is considered to be prohibitively expensive for commercial application. That ink is commercially available as would be known to those of skill in the art however the inventors consider those inks disclosed herein as their preferred embodiment for achieving the purposes of the present invention. Although no difference in scannability was found based on a difference in ambient light, it is anticipated that high density bar codes will be subject to different scannability ratings in differing ambient light conditions. It is also interesting to note that the test did not indicate any scannability difference caused by over laminating the bar code. The inventors have developed, patented, and are commercializing to great success several different versions of an over laminated wristband and this test verifies that the present invention may be used to good advantage in these previously patented constructions. 
         [0020]    An alternative embodiment  34  is shown in  FIG. 2  and includes a face stock layer  24  that has been prepared with a mix of materials such that it exhibits the desired fluorescing effect on its finished surface as detailed above with the first embodiment. Manufacturing processes as are well known to those of skill in the art, including those as known to achieve a “brightening” of the finished face stock surface, would be readily apparent and used to achieve the finished face stock of the present invention without undue experimentation. 
         [0021]    The present invention has been described in terms of a preferred embodiment of a wristband in the health care environment. The method and business form or other use of this enhanced scannability bar code could be readily used in other applications and environments. Variations of the invention are contemplated by the inventors. In a broad sense, the inventors consider their invention to encompass preparing a paper stock, face stock or other print surface that is print receptive and containing a fluorescent whitening agent for greater brightness. The fluorescent coating could be applied by a number of printing methods including flexographic, letterpress, and gravure, for example, and possibly by other methods of deposition such as spraying. Because a light coat weight is desired, spray coating is not considered a practical option given the present state of the art in spray coating as known to the inventors although that could very well change with improvements in such techniques. An alternative, not tested by the inventors, would be to use a titanium dioxide coating. Titanium dioxide is one of the most opaque and bright white pigments available in today&#39;s market. It is contemplated that it would add opacity and possibly brightness. Possible inks to be used to print the bar code include cool colors (blues and greens), and the organic blacks. Other changes and modifications would be apparent to one of ordinary skill in the art upon reading the present disclosure, and those changes and modifications are considered as part of the present invention which should be limited solely by the scope of the appended claims and their legal equivalents.