A conventional water sport shoe, as made of covering (1) as shown in
However, after a time period of service, the seam (13) may be leaked or broken due to the following reasons:
1. The chemical, such as the chlorine ion in sea water with pressure (P), may cause the degradation of the adhesive in the seam, thereby resulting in joint failure or leakage (L) of the shoe.
2. As being compressed by the water pressure (P), especially when immersed in a deep sea, the shoe covering made of rubber foam may be thinned under the high water pressure. However, the hard impurities, as formed during the foaming process of foam, may not be thinned. A water leakage (L) may then be formed through such impurities in the foam, thereby causing water penetration into the wearer's foot.
3. Even not subjected to high water pressure, the seam at two joined foam panels or sheets may still be leaked after repeated use, such as due to mechanical stress and strain.
The present inventor has found the drawbacks of a conventional water sport shoe, and invented the present double-layer footwear for precluding water penetration through the footwear.
The object of the present invention is to provide a double-layer footwear, especially a water sport footwear, comprising: an outer rubber foam panel defining a first joint member in an outer seam in the outer rubber foam panel, and an inner rubber foam panel defining a second joint member in an inner seam in the inner rubber foam panel and adhered with the outer rubber foam panel with an adhesive, with the second joint member being projectively separated from the first joint member with a barrier distance, to thereby securely preclude water penetration through the outer and inner seams into a wearer's foot.
As shown in
Two fabric layer 4 (
As shown in
As shown in
As shown in
The outer rubber foam panel 1 and the inner rubber foam panel 2 are adhered and joined by an interface adhesive 3, which may also be a rubber adhesive, to form the covering 10 of the footwear.
The second joint member 23 is projectively deviated or separated from the first joint member 13 with a barrier distance D for securely precluding any unexpected water penetration through the outer seam with the first joint member 13. The word “projectively” used herewith is intended to define the two joint members 23, 13 are separated from a projective view of the covering of the two rubber foam panels 2, 1.
The “barrier” distance D may also be referred as a safety distance between the first joint member 13 (at outer seam) and the second joint member 23 (at inner seam), whereby even unexpected incoming water penetrates through the outer seam of the first panel 1, the interface adhesive 3 bonded between the first and second panels 1, 2 may still preclude the inward penetration of the incoming water, thereby ensuring an excellent water-proof effect for the footwear of the present invention.
Such a barrier distance D is not limited in the present invention, and may be at least 6 mm, or may be a quarter of the periphery of a footwear boot (
For absolutely precluding any water penetration, a sealing tape (not shown) may be further provided to fasten a bottom of the second joint member 23 (or inner seam). Such a sealing tape may include a heat tape made of hot melt PU adhesive or a glue tape made of Neoprene and rubber adhesive. but not limited in the present invention.
The rubber foam or rubber sponge of the present invention may include Neoprene, Styrene-Butadiene Rubber (SBR), etc.
The outer panel 1 may have a thickness of 1.5˜5 mm, while the inner panel 2 may have a thickness of 1.5˜6 mm but not limited in this invention.
Thanks to the barrier distance D between the outer joint member 13 at the outer seam and the inner joint member 23 at the inner seam. The incoming water even penetrates inwardly through the first joint member 13 (outer seam), if unfortunately failed or not bonded, the incoming water will be precluded beyond the barrier distance D of the interface adhesive 3 as adhered between the outer and inner panels 1, 2, and will not attack the second joint member 23 at the inner seam as projectively separated from the first joint member 13.
Otherwise, if there is no barrier distance exists, the second (or inner) joint member 23 will be aligned with the first (or outer) joint member 13. The water, after attacking the first joint member 13 (outer seam), if failed or deboned, will directly penetrate inwardly to attack the second joint member 23 (inner seam), thereby possibly causing leakage through the seams of the two panels 1, 2 and causing water penetration into the wearer's foot to make him or her uncomfortable wearing.
The joint member 13, 23 may include: adhesive and stitching (sewing threads) for joining the opposite end portions of the rubber foam panel or sheets. For clear illustration, the stitching is not shown in
The present invention may be further modified without departing from the spirit and scope of the present invention.
A single sheet of rubber foam panel may be rolled up and has its opposite end portions joined by a joint member to form cylindrical-shape structure, like a boot.
The present invention may produce any kind of footwear, including water sport footwears, shoes, or boots.