Patent Application
20140033389
Surfers, jet skiers, wake boarders, windsurfers, kayakers, whitewater rafters, scuba divers, and snorkelers use wetsuits for comfort and protection during water recreation. Essentially, wetsuits are a form of thermal covering that traps a thin layer of water against the wearers skin to form under an insulating material to be warmed by body heat. The insulating material commonly used for wetsuits is polychloroprene, also known as neoprene, a product of synthetic rubber. Unfortunately, polychloroprene has several major disadvantages. These include rubber allergy and high toxicity among others. With regard to rubber allergy, 15% of the world's population is allergic to polychloroprene. The American Contact Dermatitis Society labeled neoprene rubber as a common source of mixed dialkyl thioureas, which happens to have been labeled the Allergen of the Year in 2009. As for polychloroprene's toxicity, the material contains formaldehyde, phthalates, lead, and chlorine, which are all known to be harmful to humans.
Thus, there exists a clear need for a wetsuit material that is not based on polychloroprene, and does not have the allergen potential or the levels of toxicity.
It is thus an object of the present invention to provide a wetsuit and a wetsuit material that is polychloroprene-free. It is another object of the present invention to provide a wetsuit and a wetsuit material that contains polychloroprene-free material such as hypoallergenic thermoplastic elastomer foam. It is a further object of the present invention to provide a wetsuit and a wetsuit material that is polychloroprene-free and insulates as well or better than polychloroprene. It is yet another object of the present invention to provide a wetsuit and a wetsuit material that is polychloroprene-free and withstands tearing, rough handling and severe conditions. It is yet another object of the present invention to provide a wetsuit and a wetsuit material that is polychloroprene-free and is inherently flexible. It is yet another object of the present invention to provide a wetsuit and a wetsuit material that is polychloroprene-free and is inert to most chemical agents. It is still another object of the present invention to provide a wetsuit and a wetsuit material that is polychloroprene-free and is free of formaldehyde, phthalates, lead, and chlorine.
In accordance with the present invention, there is provided a polychloroprene-free wetsuit and material comprising closed cell thermoplastic elastomer foam.
The foregoing paragraph has been provided by way of introduction, and is not intended to limit the scope of the invention as described in this specification, drawings and claims.
The preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.
The present invention will be described in connection with a preferred embodiment, however, it will be understood that there is no intent to limit the invention to the embodiment described. On the contrary, the intent is to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by this specification, drawings and claims.
Wetsuit construction is performed through the use of automated machine cutting and seam bonding or hand cutting, tailoring and seam bonding. The present invention and the various embodiments depicted herein rely on the use of thermoplastic elastomer foam (TPE foam), which can be fabricated into wetsuits using either automated or hand methods, or a combination thereof.
Thermoplastic elastomer foam (TPE foam) is made up of a class of copolymers or a physical mix of polymers consisting of materials with both thermoplastic and elastomeric properties. Generally, thermoplastic elastomer foam consists of a thermoplastic elastomer (thermoplastic resin), blowing agent, additives, and fillers. Thermoplastic elastomer foam is considered a generally low modulus, flexible material that can be stretched repeatedly which is an ideal characteristic for the production of the present invention.
The first step in the production of thermoplastic elastomer foam involves the selection of a foamable thermoplastic elastomer having a suitable hardness value to permit production of soft, low-density foam. In practice the resulting foam must exhibit compressibility (i.e. load bearing) characteristics that allow the foam to deform easily and still resist permanent deformation (compression set) when the load is removed.
According to conventional technique, a thermoplastic elastomer foam may be produced by feeding a thermoplastic resin into an extruder and, through the shearing action of one or more screws, melting the resin continuously in the barrel of the extruder. In an intermediate or a mixing section, a blowing agent, usually in a liquid or gaseous state, is continuously injected into the molten resin. In some instances, a chemical blowing agent may be dispersed throughout the particulate resin in a powder form before the resin is fed to the extruder as discussed in U.S. Pat. No. 4,107,260. The entire disclosure of which is incorporated herein by reference only. In either case, the extruder screw is designed to mix and dissolve the blowing agent as uniformly as possible in the molten resin. Thorough, uniform mixing is essential to the production of high quality foam. The resultant mixture must be maintained under carefully controlled temperatures and pressures within the extruder in order to prevent the volatilization of the blowing agent.
When the molten mixture is forced through a die, the material undergoes decompression to atmospheric pressure so that the blowing agent separates within the body of material as bubbles. If the temperature is too high, there is overexpansion and the cells rupture. If the temperature is too low, there is incomplete expansion, resulting in low quality foam. In many instances, the temperature window between overexpansion and underexpansion is only a few degrees Fahrenheit.
The thermoplastic elastomer foam may contain additives, if necessary for a certain purpose of the polychloroprene-free wetsuit of the present invention, each in an amount by which the mechanical strength and the flexibility are not affected adversely, such as antistatic agent, weatherability-imparting agent, UV absorber, glidant, antibacterial agent, antifungal agent, tackifier, softener, plasticizer, filler such as titanium oxide, carbon black, dry silica, wet silica, aramid fiber, mica, calcium carbonate, potassium titanate whisker, talc, barium sulfate, and the like.
Various densities of thermoplastic elastomer foam (TPE foam) that has been expanded into a closed cell structure may be used to make the polychloroprene-free wetsuit of the present invention. Low densities, for example, less than about 0.25 grams/cubic centimeter, and preferably 0.10 to 0.20 grams/cubic centimeter, are well suited for making the polychloroprene-free wetsuit of the present invention. Other densities may also be used to make the polychloroprene-free wetsuit of the present invention.
For a general understanding of the present invention, reference is made to the drawings.
In some embodiments of the present invention, other materials may be placed on either side of the TPE foam 51 to enhance performance or to achieve desirable characteristics of the polychloroprene-free wetsuit.
To make a polychloroprene-free wetsuit of the present invention, techniques such as those known to those skilled in the art in the field of neoprene wetsuit fabrication and tailoring, are employed. For example, the thermoplastic elastomer foam material is cut to various patterned pieces, the pieces are joined together using a technique such as gluing or double gluing (glue is applied to both sides of each piece of material to be joined together), the joined and glued together pieces may optionally be nipped (a technique where pressure is applied to the joined seams), a piece of material such as heat welded tape made from a material such as stretch nylon is then placed on the inside of the seam and glued in place, the pieces are then blind stitched from one or both sides, and optionally the seams are covered with a material such as heat welded tape or the like. To complete the polychloroprene-free wetsuit, a zipper or zippers are added along with logos, and the like. As known to those skilled in the art, the steps heretofore described may be modified or adapted to various situations, materials, and wetsuit designs.
It is therefore apparent that there has been provided, in accordance with the various objects of the present invention a polychloroprene-free wetsuit and material. While the various objects of this invention have been described in conjunction with preferred embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of this specification, drawings, and claims.
