CA2431734A1 - Friction enhanced coldwater elastic bands - Google Patents

Description

FRICTION ENHANCED COLDWATER Et~,STIC BANDS
The present invention relates generally to a lobster cla~uv retainer, and, in a particular embodiment, to an elastic band suitable for placement on lobster claws.
The following patents are considered to be of general relevance to the subject matter of the present invention and are not believed to anticipate sir render the present invention obvious, whether taken alone or in any combination.
United States Patent No. 2,009,546 and Canadian Patent No. 345,895 {P.L.
Fannen et al.) entitled Lobster Claw Retaining Device describe a band adapted to be placed around the claw of a lobster to allow a small amount of movement of the claw, which eliminates paralysis. The band consists of a central heavy resilient rr~aterial, such as rubber, and an elastic band which is stretched in order to apply the band to a claw.
United States Patents. Nos. 2,138,651 {and Canadian Patent No. 365,731 ) ;

2,136,484 (and Canadian Patent No. 360,289) ; and 2,108,327 all to Barwood and all entitled Lobster-Claw Lock describe various forms of a metal claw loch. One feature of these patents is an internal surface which serves to provide a ceirtain amount of friction between the lock and the lobster claw. The '651 patent teaches depressions preferably bent out of the sheet material to produce torus-shaped curves adapted to bite against the lower and outer edge of the claw to prevent slipping. The '4841 patent discloses a roughened inner wall preferably achieved by transversely disposed corrugations adapted to engage against the edge of the claw to resist movement. The '327 patent describes toothed inner surfaces to prevent the lock from slipping off the claw.
United States Patent No. 5,147,705 and Canadian Patens, No. 2,031,701 (Ta-Shun et al.) entitled Elastic Band describes an elastic band comprising longitudinal serrated projections, designed for improved securing of articles. The band is intended to provide an elastic band that can secure articles in a manner that prevents slipping, without using a large tightening force. This elastic is described as useful for clothing, such as stockings, trousers and hats, but may be applied to a variety of othE:r areas.
United States Patent No. 5,397,832 {Ellul) entitled Thermoplastic elastomer having improved low temperature properties discloses a method for preparing thermoplastic elastomers having improved low temperature properties. lin particular, these improved low temperature properties are provided by incorporating certain types of low molecularweight ester plasticizers into a blend of crystalline polyolefin homopolymer or copolymer and olefinic rubber. The patent also discloses certain fillers, including silica and titanium dioxide, which may be used in the elastomer composition.
United States Patent No. 0,403,722 (Severe et al.) entitled Dynamically Vulcanized Elastomeric Blends Including Hydrogenated Acrylonitriie-Butadiene Copolymers describes a dynamically vulcanized elastomeric blend comprising hydrogenated acrylonitrile-butadiene copolymers (HNBR) for use as a substitute for substantially homogeneous blends of HNBR. In this patent, HNBR may be cured using sulfur, peroxides, or derivatives thereof, such as sulfur donorslaccelerators, which include TMTM and MBTS.
Additionally, the elastomeric blend may be compounded with various conventional additives, including stearic acid, plasticizers, cure accelerators, and zinc oxide, and fillers, including hydrated silica and titanium dioxide.
United States Patent No. 5,407,174 (Ouhadi) entitled Propylene/Ethylenelcx-Olefin Terpolymer Thermoplastic Elastomer Vulcanizates discloses a thermoplastic elastomer vulcanizate which is obtained using a thermoplastic propylene/ethylene/a-olefin terpolymer, a rubber component and options! additives. The thermoplastic elastomer is prepared by dynamic vulcanization of the rubber component with a non-peroxide curing system. One of the olefinic rubbers described as being suitable for the invention is natural rubber, such as crepe. Additionally, antioxidants such as styrenated phenol may be utilised in the composition as chemical protectors.
The bands disclosed in U.S. Patent No. 2,009,546, and Canadian Patent No.
345,895 patents are made of elastic material and are stretched around the claws of a lobster, and bear a central portion made of a heavy resilient material aidapted for placement between the claws, allowing a small amount of claw movement. However, these patents fail to disclose a roughened inner surface of the band to prevent slippage.
Furthermore, these patents do not teach or suggest the use of an elastic material that does not deteriorate or harden in cold water.

The lobster-claw locks disclosed by Barwood in U.S. Patents Nos. 2,138,651, 2,136,484, and 2,108,327 and the counterpart Canadian patents disclose means far increasing the friction between the claw lock and the claw, which prevent the devices from slipping off the lobster claw, however these locks are made of metal, and are of somewhat complex design.
United States Patent No. 5,147,705 teaches an elastic band having longitudinal serrated projections on the interior surface of the band. These serrations are designed to increase the friction between the band and the item that it grips., however this particular band appears to be designed for articles of clothing and the patent does not disclose the use of rubber having high resistance to cold temperatures.
U.S. Patent No. 5,397,832 discloses a thermoplastic elastomer that has improved low temperature properties. According to the disclosure of this patent, the improvement in IS performance of the thermoplastic elastomer at low temperatures is provided by incorporating a suitable low molecular weight ester plasticizer into the polymer blend.
U.S. Patent No. 6,403,722 discloses curing agents such as sulfur, TMTM and MBTS, as well as additives, such as stearic acid, and zinc oxide, and fillers, such as hydrated silica and titanium dioxide. U.S. Patent No. 6,407,174 discloses the use of crepe rubber in an elastomer composition, as well as antioxidants such as styrenated phenol.
According to an aspect of the present invention there is provided a lobster claw retainer comprising an elastic band suitable for use in cold water by being formed of an elastomeric material which retains elasticity at cold vaster temperatures, the band comprising a flat loop of elastomeric material having a friction-enhancing inner surface.
According to another aspect of the present invention there is provided an elastic band being suitable for placement on a lobster claw to restrict movement of the claw. The band being made of a material which will function at least adequately in cold water and which has a profiled inner periphery which serves to grip the lobster claw.
Embodiments of the invention will now be described, by vvay of example, with reference to the accompanying drawing, in which:
_3_ Figure 1 is a perspective view of an elastic band according to an embodiment of the present invention.
The present invention comprises a rubber band 1 for placing over the claw of a live lobster for restricting the movement of the claw. The rubber band is slipped around a claw of the lobster to inhibit or substantially prevent opening of the claw. The rubber band may have two important features. The first is the provision on the inner surface of the rubber band of a roughened or profiled surface 2 such as a series of ribs 3 in parallel relationship around at least a portion of the inner surface of the band. The purpose of this is to increase the coefficient of friction as between the band and the lobster claw to mitigate or prevent accidental or unwanted slippage of the band from the claw. The previous use of a band with a smooth inner periphery which contacted the lobster claw was found to be inefficient and lacked the facility for ensuring a relatively firm and permanent grip on the restrictive movement of the lobster claw. The ribs 3 are advantageously mutually parallel and normal to the circumference of the band. In one embodiment, the ribs 3 may be spaced at intervals of about 0.5 to 1.5 mm, advantageously about 1 mm.
Ideally, the ribs

3 have a height of from about 0.1 to 0.5 mm. Other forms of roughened inner surface may be envisaged such as a gnarled surface or one which has formed thereon a series of arrowhead shaped peripheral protrusions. Many other forms of roughened or profiled inner surface may be envisaged which could perform the function of inhibiting slippage.
In one embodiment the width of the band is between 1/~d and 1 inch; the thickness is between 0.038 and 0.075 inches; and the lay flat length is between 3/4 and 5 inches.
Another feature of the rubber band resides in the actual chemical composition of the rubber. Rubbers which have been used in the past have tended to degrade or harden under the influence of the very cold water to which they tire subjected when attached to the lobster claws and the cold water also substantially reduces or eliminates the elasticity of the band which is important for good function. The proposed rubber will successfully withstand extensive submersion in very cold water while being used to restrict the movement of the lobster claws. The rubber has been fcaund not to readily degrade or harden and thus can be used repetitively without loss of function, such as the gripping or elastic facility.
A preferred composition of the rubber for use in these elastic bands is shown in Table 1.
_4_ Table 1. Preferred Composition of Elastic Band Material ~osage ~P~W~

High Quality Crepe Rubber 100.000 S

ZnCO - Active (inorganic activator}1.000 Stearic Acid {surfactant) 1.000 Mediaplast NS 20.000 Hydrated Silica (Hisil 255 3.000 S) (mainly Si02, rubber stregthening agent) MBTS - dibenzolthiazyldisulfide1.000 {widely used organic accelerator) TMTM (secondary accelerator) 0.02 Styrenated Phenol 1.000 Insoluble Sulphur 2.0'00 Ti OZ {White pigment) 2.000 Total 127.020 The information in parentheses provides further description of the component generally and does not necessarily indicate the function of the component in the above composition.
Furthermore, a variety of different formulations of this rubber composition may be envisioned, by using alternative curing agents, additives and fillers, or by modification of the concentrations of these agents, providing that the resulting composition retains the desired functionality.
_5_ Mediaplast NS is a preferred plasticizer, but either Mediaplast NS or Thiokol TP 95 may be used to produce this band. Mediaplast NS is a non-staining plasticizerforgeneral use, consisting of synthetic hydrocarbons with excellent love temperature properties. The compatibility with most elastomers is very good and the use is recommended for NR, SBR, CR, EPDM and BR. With strong polar polymers like NBF; it is only limited compatible.
Testing has shown that the preferred amount of rubber to used is be in the range of 75%
to 100%. The Rubber Quality is preferably TCP IX.
The above compounds represent a preferred embodiment of the present invention.
Certain of these compounds could be substituted by a suitable replacement as would be evident to one skilled in the art since a wealth of knowlE:dge exists in the art of elastic bands, rubber and related areas of technology. Additionally, the amount of each component could be varied.
In order to achieve a friction-enhanced inner surface, the surface may be provided with ribs or other embossments or grooves as discussed above. In addition, a rough surface may be achieved by incorporating other particles onto the surface.
Uses other than for restricting the movement lobster claws are envisaged. For instance, these bands could be used for restricting movement of other living creatures such a crabs or for uses currently known and as of yet unimagined for elastic bands.

Claims