Abstract:
A fluorescent material is formed of two sets of fibers, one set being receptive to standard dyes and the second set being receptive to fluorescent dyes. The material thus formed has a standard color under normal light, and a pleasing fluorescent color under UV light. The two colors can be very different. The fibers are preferably colored using a cross-dyeing process after they are formed into the material. The material can be knit or woven.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    a. Field of Invention  
           [0002]    This invention pertains to a material that has a standard color under a normal light and a fluorescent color under a UV light. The material is formed of two kinds of fiber; fibers receptive to standard dyes and fibers receptive to fluorescent dyes. Preferably, the fibers form either yarns or yarn components.  
           [0003]    b. Description of the Prior Art  
           [0004]    Most materials when viewed under a UV light have either the same color, or a somewhat muted color when compared to how they look under normal light. However, certain materials can change color or, more appropriately, appear to have a different, more vibrant color when exposed to UV light then under normal illumination. For example, white dress shirts acquire a vibrant, fluorescent bluish color under a UV light. In many instances this effect is esthetically pleasing and desirable. Manufacturers of cleaning products, such as laundry detergents, are very aware of this phenomena and they add specific substances in their products to emphasize this effect.  
           [0005]    These materials can be said to have two colors: a normal and a fluorescent color. (The term ‘fluorescent’ color is used herein to refer to the color of a material when illuminated by UV light). Of course, as discussed above, not all materials exhibit this characteristic, and therefore a material may have at most one standard and one corresponding fluorescent color, thereby severely limiting the number of color choices for a fabric.  
         OBJECTIVES AND SUMMARY OF THE INVENTION  
         [0006]    In view of the above, an objective of the present invention is to provide a material having a standard and a fluorescent color wherein each color is selectable by the manufacturer.  
           [0007]    A further objective is to provide a material with a selectable fluorescent color that is readily made using standard manufacturing techniques.  
           [0008]    Yet a further objective is to provide a fluorescent material that can be made inexpensively.  
           [0009]    Other objectives and advantages of the invention are described in the following description.  
           [0010]    Generally speaking, a fluorescent material is disclosed that is formed into a fabric from two sets of fibers, one set being receptive to standard dyes and the second set of fibers being receptive to fluorescent dyes. Each set of fibers is dyed to one of the respective colors, either before, or after being formed into the material. Each set of fibers forms a respective set of yarns. Alternatively, fibers from each set are intimately blended into yarns to form yarn sets.  
           [0011]    In another aspect of the invention, a material is made in accordance with the present invention from a yarn system wherein, in one embodiment, the yarn system includes two different yarns, the yarns having different composition, and/or other physical characteristics, such as fiber count. The material may be formed from the two yarns by weaving, knitting, or any other form, and is structured and arranged so that one of the yarns primarily determines the normal color of the fabric while the second yarn primarily determines the fluorescent color of the material. In a somewhat preferred embodiment, a single yarn is used to form the material, with the yarn being formed of two yarn components that are intimately blended. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0012]    A material constructed in accordance with this invention, is woven, knitted or prepared by other means from a yarn system using standard techniques for making fabrics. The yarn systems consist of yarns, with at least some, or all of the yarns being formed of at least a first and a second yarn component. The first yarn component is formed of fibers that can be dyed with (or receptive to) a standard color. The first yarn component may be of cotton fibers; cotton blended with a natural or artificial fiber; or other fibers such as polyester, nylon, rayon and so on. The second yarn component is made of fibers that can be dyed with (or receptive to) a fluorescent color. This second component may be made of polyester, nylon, acrylic, cotton or other similar natural and artificial fibers. The two types of fibers are intimately blended to form a composite yarn in which the two types of yarn fibers are difficult to distinguish, at least visually. It was found that the ratio of the first to the second fibers by weight could be anywhere from 50/50 to 80/20. In an alternate embodiment, the yarn systems include at least two different yarns, each yarn having the characteristics of one of the yarn components described above. The yarns can have any size, such as 20/1, 40/1 etc. The following table illustrates some of the yarns have been used, it being understood that other types of yarns can be used as well.  
                                               Fabric                       Designation   Yarn size   Yarn composition   Spun type   Blend                   A   20/1   60% cot-40% poly   open-end   intimate       B   18/1   60% cot-40% poly   open-end   Intimate       C   40/1   60% cot-40% poly   ring   intimate       D   22/1   60% cot-40% poly   ring   intimate       E   ┌ 30/1        100% cot   ring ┐   separate           └ 30/1        100% poly   airjet ┘   knitted feeds       F   2/70/68/72   50% ny-50% poly       Continuous                       textured                       Commingle                       filament                                          
 
         [0013]    Once the material is formed, it is then cross-dyed so that it obtains predetermined color characteristics. That is, various dyes are applied to the material either sequentially or simultaneously so that the first fibers become a first color and the second fibers become a second color. The first and second colors are similar but necessarily identical to the standard and fluorescent colors as illustrated below. Techniques of cross-dyeing are well known in the art.  
         [0014]    After the dyeing of the material is completed, the material may be used to form various articles, such as garments or other articles of apparel, including sportswear, outwear, intimate apparel, active wear, swimwear, workwear(uniforms), children&#39;s wear, sleepwear, loungewear, footwear, scarves, kerchiefs, neckties, buttons, ribbons, belts, stockings, etc. Other articles include household articles such as furnishings, upholstery, rugs, carpets, etc.  
         [0015]    In an alternate embodiment, the material is woven or knit into a fabric composed of two types of fibers as discussed above, the fabric sewn or otherwise shaped into an article, and the article is then cross-dyed, as described above.  
         [0016]    The following are some examples of implementing the subject invention. In all these examples, yarn component 1 is made of cotton and yarn component 2 is made of polyester intimately mixed at a ratio of 60/40.  
                                                   Yarn 1   Yarn 2   Standard   Fluorescent       Example #   Color   Color   Color   Color                   1   Purple   Green   Brown   Green       2   Royal blue   Green/yellow   Blue   Green       3   Red   Pink   Red   Salmon       4   Gray   Pink   Pastel pink   Bright salmon       5   Green   Yellow   Seaweed   Bright yellow       6   Orange   Yellow   Tangerine   Bright orange                  
 
         [0017]    As can be seen from these examples, the color of the first yarn is similar but not necessarily the same as the standard color and the color of the second yarn is similar but not necessarily the same as the fluorescent color. That is because in some cases the material colors result from the color of both yarns. More specifically, in example 1 the standard color-brown is the result of the first yarn being purple and the second yarn being green. On the other hand, in some instances the standard color may be substantially identical to the color of the first yarn, while the fluorescent color may be identical to the second yarn. More particularly in example 3 the second yarn-pink was virtually invisible and this did not substantially affect the standard color. Thus, in general, the first color primarily determines the standard color and the second color or primarily determines the fluorescent color.  
         [0018]    In the embodiments described so far, the material is described as having a fluorescent color under a UV light and a standard color otherwise. However, the second yarn component (or second yarn) may be made of fibers that remain fluorescent for a relatively long time period even after the material is removed from the UV light.  
         [0019]    While the invention has been described with reference to several particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles of the invention. Accordingly, the embodiments described in particular should be considered as exemplary, not limiting, with respect to the following claims.