Abstract:
A knitted casting glove that, when wetted, imparts a detackifying property to a sticky work surface. The glove comprises a knitted yarn of a base material and water-soluble material having a low dissolving point or a base material and a water-swellable material. The knitted casting glove may be worn over a standard examination glove.

Description:
RELATED APPLICATIONS  
       [0001]    This application claims priority of U.S. provisional patent application Serial No. 60/332,157 entitled, KNITTED CASTING GLOVES, filed Nov. 21, 2001 by Gerber et al., herein incorporated by reference in its entirety. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to knitted casting gloves used for any molding or modeling application where a slippery, non-stick glove is beneficial to the user. More specifically, it relates to gloves used as casting gloves by physicians and technicians in setting broken limbs.  
         BACKGROUND OF THE INVENTION  
         [0003]    Casts used by physicians to set broken limbs typically are bandages made of plaster, polyester or fiberglass applied on the fabric of the bandage or orthopedic casting tape. The cast must be applied to the broken limb by hand and generally requires dipping the bandage in water or some other curing agent prior to wrapping the cast in place on the limb. As the bandages are being set on the limb, the curing or drying process is underway and the bandage materials may become tacky. The physician&#39;s hands may begin to adhere to the cast before the cast is completely finished.  
           [0004]    To prevent the physician&#39;s hands from adhering to the tape or bandage material a lubricant is applied to the physician&#39;s hands or gloves to allow the gloves to slip over the curing tape or bandage material until the physician is prepared to terminate the cast. Methods for delivering the lubricant to the gloves have included providing a dry coating to the gloves that will become lubricious when brought into contact with water. Gloves having lubricant impregnated substrates have also been used. The gloves are typically latex with a lubricating polyvinyl alcohol (PVA) external coating. The PVA may be thickened with rhamsan gum, for example. The external coating is applied to the glove by dipping the glove in a solution of the lubricant, followed by drying the lubricant. The drawback to these types of gloves is that they may be difficult to manufacture reproducibly. The gloves also may be stiff, subject to cracking, or flaking off of particles. Also, the user is left with little manual control should the user need to manipulate small items such as a pen or scissors while using the gloves.  
           [0005]    Additional methods of delivering the lubricant to gloves include the application of a casting cream consisting of water, mineral oil, sorbitol and silicon to the gloves after wrapping the cast but before molding the cast. However, incorporating oil-containing lubricants into curable compositions may result in a longer setting time for the cast.  
           [0006]    Another method for controlling the amount and location of the lubricant involves swabbing a lubricant onto the glove with a porous, flexible substrate as an applicator. The lubricant-impregnated porous substrate may be used to deliver the lubricant as needed to gloves or other surfaces that contact a tacky substance. One or both of the lubricated substrate or gloves may be wetted with water or immersed in water before swabbing the lubricant onto the glove. The substrate may be a knitted or woven textile or fabric including cotton. The drawbacks to using the substrate as an applicator of the lubricant is that multiple applications of the lubricant to the glove may be required during casting and added steps are required for lubricant delivery as compared to the gloves having a lubricating layer. The multiple applications and added steps are undesirable as they increase the time required to complete the casting procedure.  
           [0007]    Accordingly, there is a need for a glove that imparts a detackifying effect on the sticky surface of casting materials that does not increase the application time or cure time of the casting process. There is also a need for a casting glove that allows some tactile manipulation of small items such as pens and scissors.  
         SUMMARY OF THE INVENTION  
         [0008]    The present invention is a knitted glove for use in setting casts on broken limbs or for use in handling any tacky molding or modeling activities such as ceramic molding or where a slippery non-stick glove is beneficial. When wetted, the glove imparts a detackifying effect on the sticky material. This glove eliminates stiffness, cracking, and flaking off of particles, and increases longevity of the gloves during use. The glove is designed to, optionally, be worn over a standard exam-type glove and is made from a water soluble, water-swellable polymer or fiber. The glove will swell, soften or at least partially dissolve into a slippery lubricious surface when wetted. The knitted glove may be made of polyvinyl alcohol (“PVA”), Co-Nylon, or low dissolving point polymer, or a blend of any of these materials, for example. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0009]    The invention provides gloves of various knitted materials that impart a detackifying effect on a sticky work surface. These gloves include gloves made from materials further identified in Table 1 below.  
                             TABLE 1                           Summary of Materials Use in Casting Gloves.            Material   Details   Characteristics               Cotton-PVA 30   51:49 Cotton: PVA 30/1   Water soluble PVA/Cotton Blend       Cotton-PVA 40   51:49 Cotton: PVA 40/1 260 dn   Water soluble PVA/Cotton Blend       PVA #1   500 dn   Dissolving point approx. 180° F.       PVA #12   500 dn   Dissolving point approx. 85° F.       Co-nylon   700 dn   Water soluble nylon       Isolyser   380 dn   Water soluble PVA yarn       Nylon   2/70 Nylon 150 dn   Base material       Polyester/Cotton   22/1 Polyester/Cotton   Base material                  
 
         [0010]    In Table 1, the abbreviation “dn” refers to the denier of the corresponding fiber. Cotton-PVA 30 refers to the size yarn, i.e. size 30 and, similarly, Cotton-PVA 40 refers to size 40 yarn. PVA 30/1 refers to size 30 single ply yarn. In a similar fashion, PVA 40/1 refers to size 40 single ply yarn. The Cotton-PVA 30 and Cotton-PVA 40 materials were obtained from Itochu in Osaka, Japan. Isolyser materials are available from Orex Technologies of Norcross, Ga. The PVA #1, PVA #12 and Co-nylon materials were obtained from Fiber Science, Inc. in Palm Bay, Fla.  
         [0011]    The dissolving points of the PVA #1 and PVA #12 materials is determined by the manufacturer by measuring a length of yarn and tying a washer weighing between 5 and 10 grams to one end of the length of yarn. The yarn and washer are then submersed in a vessel of water such that the washer does not rest on the bottom of the vessel of water. The water is then slowly heated until the yarn breaks and the washer falls to the bottom of the vessel. The dissolving point is reported to be the temperature at which the yarn breaks and the washer falls to the bottom of the vessel.  
         [0012]    Base material refers to the material being blended with a PVA material such that a spool of the material is knitted together with a spool of PVA material. Another method of combining materials is known as upwinding. During upwinding, strands of different materials are wound together to produce a single yarn of more than one material.  
         [0013]    Test gloves were knitted on one of two different knitting machines. One machine was a 15-gauge knitting machine and the other was a 13-gauge 83 needle machine. Twelve types of gloves were produced for use in a sample casting procedure. The gloves are identified as samples A-L. Table 2 summarizes the test materials of each sample glove A-L.  
                                                           TABLE 2                           Materials of Sample Gloves A-L.                Polyester/                Material   Cotton-PVA 30   Cotton-PVA 40   PVA #1   Nylon   Cotton   Isolyser               Cotton/PVA 30   B           J       G, I       Cotton-PVA 40       A               C       PVA #1   H       L       Nylon                       D       Polyester/                   F   E       Cotton       ISOLYSER                       K                  
 
         [0014]    In Table 2 above, the data means the particular gloves are a blend of materials as indicated by the glove&#39;s position in the table. For example, Glove J is a blend of nylon and Cotton-PVA 30 from two spools knitted together.  
         [0015]    The gloves were subjectively analyzed for donning, wearability/comfort and casting durability properties. The gloves were placed over standard examination gloves when determining testing. Powder-free nitrile and polyvinyl chloride examination gloves were used as representative examination gloves. The results of this analysis are summarized in Table 3.  
                             TABLE 3                           Summary of Donning and Durability Properties of Sample Gloves A-L.            Glove   Specifications   Dry Glove Properties               A   15-gauge, 2-end, size 9   Soft, flexible, easy to don       B   15-gauge, 1-end (open weave), size 9   Soft, flexible, easy to don       C   15-gauge, size 9   Heavier than A and B, fairly soft       D   15-gauge, size 9   Heavy, boardy, less stretch       E   15-gauge, size 9   Very stiff and heavy       F   15-gauge, size 9   Somewhat stiff, tight feeling       G   15-gauge, 7 courses of elastic in cuff, size 9,   Same as C, comfortable           weight is 14.2 grams       H   15-gauge, size 9   Satiny, soft, fairly heavy       I   13-gauge, 14 courses of elastic in cuff,   Similar to G, stretchier, easier to don           size 9, weight is 13.3 grams       J   13-gauge, 1-end, Cotton-PVA, 2-end nylon,   Soft, flexible, stretchy           size 9       K   13-gauge, 1-end, size 9   Very soft, flexible, stretchy       L   13-gauge, 1-end, size 9   Silky soft, has acetic odor                  
 
         [0016]    The glove materials imparted various properties to the gloves when the gloves were wetted. Table 4 summarized the particular properties imparted to the gloves from the various materials evaluated.  
                             TABLE 4                           Summary of Properties Imparted to Wetted Gloves.            Material   Characteristics   Properties Imparted to Glove               Cotton-PVA 30   Water soluble PVA/Cotton   Rapid and near complete dissolution,           Blend   minor shrinkage, moderate slip.       Cotton-PVA 40   Water soluble PVA/Cotton   Rapid and near complete dissolution,           Blend   minor shrinkage, moderate slip.       PVA #1   Dissolving point approx.   Gloves exhibit slight dissolution (matrix           180° F.   remains intact), severe shrinkage,               excellent slip.       PVA #12   *Dissolving point approx.   Gloves exhibit slight dissolution (matrix           85° F.   remains intact), severe shrinkage,               excellent slip.       Co-nylon   Water soluble nylon   Rapid dissolution resulting in a slippery,               slimy gel.       Isolyser   Water soluble yarn   Minimal dissolution at room temperature,               glove matrix does not stick to the cast,               minor shrinkage.                          
 
         [0017]    To test the performance of each glove, the gloves were used in a simulated casting procedure. The simulated casting procedure consisted of the following steps:  
         [0018]    1. Optionally donning an examination glove prior to donning a casting glove.  
         [0019]    2. Donning the casting glove.  
         [0020]    3. Immersing the gloved hands and a roll of casting material in room-temperature water.  
         [0021]    4. Wrapping the casting material around a mandrel to form a cast of at least 12 inches.  
         [0022]    5. Smoothing the edges of the cast by stroking 30 times in a back and forth motion.  
         [0023]    6. Repeat steps 3-5 with additional rolls of casting tape. finished.  
         [0024]    The casting procedures were conducted using Delta-Cast Polyester Tapes from DePuy Orthopedics of Raynham, Mass. The goal of the procedure was to cast two rolls of casting tape using a single pair of knitted casting gloves. The casting performance of each glove is summarized in Table 5.  
                         TABLE 5                           Summary of Casting Performance of Gloves A-L.            ID   Casting Performance               A   Dissolves fairly quickly, leaves slime around the cuff. Cast 1 + tapes. Performed           better on nitrile gloves than on PVC gloves.       B   Dissolves fairly quickly, split apart, left slime on the cuff. Imparts minimum           lubricity, messy.       C   Slight shrinkage, not extremely slippery, but does slide on the cast.       D   Lots of shrinkage, very slippery. Excellent casting performance, completed 2 tapes           and could have done more.       E   Glove stretches a great deal when wet, very slippery / too slimy. Cast feels slimy           when done.       F   Stretches a lot when wet. Casting is slippery but excess fabric from stretching balls           up and catches.       G   Similar to C, a little slipperier and more shrinkage. Excellent longevity-120 strokes,           at least 4 casts. Does not allow edges to be smoothed efficiently. Cuff shrank to           heel of hand and occasionally grabbed.       H   Excellent casting, good at smoothing edges. Severe shrinkage resulting in restrictive           fit during use. Casts 2 tapes maximum. Strong odor, leaves cast slimy.       I   Casting equivalent to that of G with better wet shrinkage. Longer cuff may have           helped minimize shrinkage.       J   Not slippery enough, picked up cast color.       K   Baggy when wet, doesn&#39;t shrink. Can cast, but has some friction.       L   Severe shrinkage, very slippery. Casting is great. Could oversize gloves to offset           shrinkage.       100%   Glove dissolves rapidly leaving a slippery gel. Casts 2 rolls.       Co-nylon                  
 
         [0025]    Based on the described analysis and results, the best performing gloves were gloves that were partially soluble, but maintained integrity during casting. The casting process was less messy if the gloves were partially as opposed to completely soluble. Glove sample “I” gave the best overall performance. Glove I imparted enough slip during the casting process, yet retained a degree of friction required to grip and handle other objects such as pen and scissors. The glove had the benefit of added durability as they survived the casting of a number of tapes.  
         [0026]    It should be understood that various changes and modifications to the embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without demising the attendant advantages. It is, therefore, intended that such changes and modifications be covered by the appended claims.